Kerbin - Mun fuel station mission. Establishing K.G.01 and K.G.02

[DeadJohn]

On 8/16/2023 at 7:28 AM, BechMeister said:

I played a lot around with wing angle and size. I really like the look of the Dream Chaser with its upsweep wings - which apparently should give more lift? I really liked the look of my glider with upswept wings too and imagined it makes sense for when you re-enter the atmosphere? that the bits dont stick too much out from the center of the craft that will be burned off

Dream Chaser is a special case because it's a lifting body with small wings, and the wings are almost more like rudders than wings, but in general upswept wings (aka "dihedral") provide roll stability. If a dihedral plane starts to rolls to its left, the left wing will begin generating more lift than the right wing, causing it roll right to a neutral level.

34 minutes ago, BechMeister said:

This is when I added the canards again.. and gentlemen this difference: This tiny difference - is 400 more Δv, 1t less methane to get to the mesosphere. It's reaching 1000 m/s at the end of the troposphere instead of at the beginning of the mesospheres - and it has gentle landings. (the the air brake was redundant in the end) It is odd that two tiny "wings" should have such an effect - I suspect there is something more to it that is hidden in the physics model.

Canards are a miracle in KSP. They can compensate for some of the game's physics simplifications and for less-than-perfect plane designs. Canards simultaneously make a KSP plane more stable and more agile. That stability+agility helps the nose of the plane face prograde, and you get more drag savings along the fuselage than you lose to the extra canard wing surface. At least that's what I think is happening.

The only way to go wrong with KSP canards is if you make them excessively large where they create so much drag near the nose that the plane flips.

[BechMeister]

7 hours ago, DeadJohn said:

Dream Chaser is a special case because it's a lifting body with small wings, and the wings are almost more like rudders than wings, but in general upswept wings (aka "dihedral") provide roll stability. If a dihedral plane starts to rolls to its left, the left wing will begin generating more lift than the right wing, causing it roll right to a neutral level.

That's interesting! because the problem - when I had the wings in a dihedral configuration  - was that the plane would start rolling the point were it got into an uncontrollable roll - so that must mean the game does not moddel that part of the physics that well?

7 hours ago, DeadJohn said:

Canards are a miracle in KSP. They can compensate for some of the game's physics simplifications and for less-than-perfect plane designs. Canards simultaneously make a KSP plane more stable and more agile. That stability+agility helps the nose of the plane face prograde, and you get more drag savings along the fuselage than you lose to the extra canard wing surface. At least that's what I think is happening.

Yeah!  - The interesting thing is that in the VAB I cannot see anything happening with the drag arrow or mass when I add the canards  - but ingame i feel the effect and I was surprised how drastic it was. That I could carry 1t less methane was big! It was a 1/3rd of the total methane it had for atmospheric flight. As of now I have canards on everything. Something in me just really wanted to design something without canards. 

I think I was careful with center of mass and drag. The grey colour on the center of the fuselage is the inline docking port - and that's center of mass. Center of lift is just behind that. - but yeah. I was also considering that maybe the plane without the canards only fly straight by using control surfaces or engine gimbling? - which means more drag and less efficient thrust right?

Any way, it does the job now, as efficient as possible. thats whats most important x)  

8 hours ago, Sylvi Fisthaug said:

This looks like the A 12 and the Blackbird lined up against eachother! 

they both fly really well too - the old one just have a lot of excess  Δv - the white one would be a lot quicker to orbit if I added 4 engines though. But - I like the 3 engine look

[DeadJohn]

21 minutes ago, BechMeister said:

That's interesting! because the problem - when I had the wings in a dihedral configuration  - was that the plane would start rolling the point were it got into an uncontrollable roll - so that must mean the game does not moddel that part of the physics that well?

Real wings have airfoil shapes that generate lift even if facing prograde at 0 degree angle of attack. KSP1 and I think KSP2 don't have airfoils; the wings are essentially flat boards that mostly lift via their angle of attack. Dihedral in KSP wings might still help but it's different than with a real plane. KSP has never been intended to replicate the atmospheric physics of a flight simulator.

31 minutes ago, BechMeister said:

The interesting thing is that in the VAB I cannot see anything happening with the drag arrow or mass when I add the canards  - but ingame i feel the effect and I was surprised how drastic it was.

You are using the canards as moving control surfaces, correct? It's their control rather than lift that's probably making the difference. Imagine a well-balanced plane with zero elevator surfaces, which might fly straight  but would be very difficult to change pitch to climb/dive. Then add a small elevator and you'll have some control. Make the elevator bigger or add a canard near the nose and you'll have even more control. Take it too far, though, and too much control can cause the plane to flip when you try turning.

 

 

[BechMeister]

1 hour ago, DeadJohn said:

KSP has never been intended to replicate the atmospheric physics of a flight simulator.

Touché!

 

1 hour ago, DeadJohn said:

Real wings have airfoil shapes that generate lift even if facing prograde at 0 degree angle of attack. KSP1 and I think KSP2 don't have airfoils; the wings are essentially flat boards that mostly lift via their angle of attack

Okay! So making the wings thick only adds drag and not lift?

1 hour ago, DeadJohn said:

You are using the canards as moving control surfaces, correct?

Correct. The plane has moving control surfaces on the tip of the wing too - the outer wing bit beyond the two wing engines. 

Right now they are limited to 15° and i have them deployed at 10° at low speed and they can only roll and pitch. I guess i kind of use them like "flaps" except the are "flapping" the wrong way for them to be flaps x) - Sorry the lingo gets very basic xD

The front canards i have not tinkedred - they have all control features.

The only actual "wing" on the plane is between the fuselage and the engines.

1 hour ago, DeadJohn said:

Imagine a well-balanced plane with zero elevator surfaces, which might fly straight  but would be very difficult to change pitch to climb/dive. Then add a small elevator and you'll have some control.

That makes sense

Edited August 19, 2023 by BechMeister

[BechMeister]

////////////////////MISSION UPDATE\\\\\\\\\\\\\\\\\\\\
- Finishing K.G.02 - Last Instillation of Methalox -

Heavy Tug Drone leaving K.G.01 enroute to the Mun with 32t of Methalox.

Foreword:

The mission can finally continue as planned. This is the first chapter in the end of this mission. 

After fixing K.G.01, burning it into a 0° inclination and refueling it. I have finally gotten to the point were I could make a mission to refuel the heavy tug drone that didn't quite make it back to K.G.01, after its first mission to K.G.02. I can now finally fly it back to install the missing fuel tanks.

All that is left is to instal the Methalox tanks, Burning K.G.02 into a 0° inclination, and dock escape vehicles and crew to the station. Once these small steps has been complete. The Kerbin - Mun fuel station mission will finally be over.

Without further ado - let's get the last methalox load enroute to the Mun.

 

 

Mission Tasks:

A. Launch Methalox glider to K.G.01 and return 1st stage to KSC - Success

B. Refuel glider at K.G.01 and rendezvous heavy tug drone - refuel and land at KSC. Success

C. Rendezvous Heavy Tug drone with K.G.01 and load cargo - launch mission towards the mun - Success

 

Lessons Learned; Lessons Identified:

A.

Glider right before stage separation and the return of Stage 1.

I have been rather successful in founding a good formula for launching my methalox glider into space, without the rocket flipping and or expending to much fuel getting up into the mesosphere for the first stage to make it back to the ground again. Refueling K.G.01 - which took 3 missions - I tried to find a easy way to land the rocket in the vicinity of KSC. 

So far my approach is to burn back towards KSC - without getting a AP above 70km (as it can take quite a while to be able to maneuver again once you leave the exosphere). Once the rocket is enroute back towards KSC I keep it horizontal facing prograde. I will periodically burn, while in the thermosphere (~30km to 70km) gauging the rotation of Kerbin. I have found that aiming roughly here yields good results:

As soon as the rocket hits the Mesospheres I follow the prograde down, and land sufficiently within KSC - I am calling it a success as long as i am landing on the flat terrain within the mountain range surrounding KSC. Now I had a bit of trouble finding out were on the map the landing pads actually are.. and so far the only fix I could think of was placing a tiny rover on one of the landing pads - I picked the middle one in the hopes that in the future, if i cant land on the middle one, maybe i can land on either ones that are adjacent to it.

Speaking of rovers - can we have a talk about how janky rovers feel? My wheel base is pretty wide.. and even though it was I was still struggling keeping the vehicle on 4 wheels... and when it was time to stop at the landing pad.. the result was as follows:

 

I thought it was kind of funny that the rover crashed into a tree, even if they are not collidable.  Any way it works, Now I know were on the peninsula the landing pad actually is, which has made it a lot easier to "line" up KSC. Some times the pixelated icons dont help the game - I know it's the style they are going for.. but I think it hurts the UI more than it benefits it.

Any way - the mission to K.G.01 was successful and the landing of the first stage - very succesful. See a detailed walkthrough in the spoiler section bellow:

Spoiler

A small picture series of the M.R.G.V. enroute to the Mesospheres for stage separation - I really think the clouds in the base game looks really good already, and the deep blue gradient against the orange of the glider and the red of the warm engine nozzles gives a beautiful contrast. Also nice to see the Mun peak over the Horizon, reminding me where we are heading.

After controlling the decent point in the Thermosphere it is time to just allow the rocket to "glide" down to KSC.

When going down I have only 3 out of 7 engines working - the rocket is so light at this point that its to difficult to control the decent when all the engines are on - I also think it looks aesthetically cool with 3 engines burning. I can keep the craft at 700-800 m/s with 10-20% thrust.

Here the rocket slows down, while deploying the legs. Having 700+ Δv coming down gives you a lot of room to control the decent without risking running out of Δv before touching down.

And touch down - while not on the landing pad - Still very good for me!

Just had to get the angle a bit better. I think if i continue to improve my skill at this, it will become a lot easier for when the grid finds make an entry to the game and fine steering becomes possible.

B.

M.F.R.G. docked at K.G.01 and being topped op to bring as much fuel to the Heavy Tug Drone, as well as making sure it can make the journey there and back again.

The journey to the heavy tug drone and back to KSC was pretty straight forward. For some reason the  Δv bug - where it shows 0Δv when its a fuel line connecting the fuel to the engine plate - wasn't there after the undock from K.G.01. It meant that I could actually do maneuver nodes which immensely helped the rendezvous.

The correction burn of almost 7° inclination was a bit tough for the terrier to perform - I would drift away from the intersection point before the inclination had been corrected, but the rest of the tour went easy enough.

The drone was successfully refueled and the glider made it back to KSC - I even had to do a night landing. It's interesting when you only have the map, your speed and your distance to the ground to go from. I learned though that the glider can maintain speed at ÷10° - which means you can extend the glide a lot.

For detailed walkthrough see spoiler section:

Spoiler

Refueled glider leaving K.G.01 enroute to the Heavy Tug Drone.

Here the docking port of the glider is being lined up to the docking port of the Medium Tug Drone placed the nose of the Heavy Tug Drone.

And refuel mission being completed.

Glider performing the burn that puts it to a suborbital path - I still really dig how the decouplers shroud the terrier engines.. I hope they will do that forever.

Here the glider is performing breaking turns in the upper atmosphere

And the last bit of sunlight before flying instruments only.

Its a bit hard to see, but here the glider is overshooting KSC, to perform a turn and landing.

Lining up the runway and bleeding altitude.

touching down nice and easy.

careful not to scrape the paint.

And there parked outside the VAB - Now I dont have to fear landing at night # night missions unlocked.

 

C.

Heavy Tug Drone - rendezvous with K.G.01 and being refueled before being loaded with cargo.

Bugs, bugs and bugs:

This part of the mission went relatively smooth too - I Identified further issues with the inline/shielded parts. Apparently they work fine as long as you don't load or quickload while docked to them. I had loaded half the methalox tanks to the heavy tug drone when i went to sleep, and the day after I found that all my saves were a Clamp-O-Tron was connected to a Clamp-O-Tron shielded they would be registered as docked, but not acting like they were docked, moving independently of each other. 

How ever I found a fix! The shielded/inline parts will not show the option to undock - the normal clamp-o-tron will. However I have experienced inline/shielded parts stop working if you undock with the functioning clamp-o-tron. This time I tried to make a costume undock action for the shielded port and it worked.

I even tried to do the same with the clamp-o-tron shielded  on top the Cockatoo on the K.G.01 habitation module, where i made an action group that forced it to undock, even if nothing was docked to it, and afterwards I was able to dock my probe to it.  It made me happy to know that K.G.01 is not broken anymore! (relevant bug report has been updated)

Synergy Issues:

I found out that the station has another synergy issue. While the Heavy Tug Drone grew in size to be able to go to the Mun and back again, the fuel tanks did not. Right now K.G.01 has 64t methalox - How ever the heavy tug drone has 33t fuel in it. Right now K.G.01 Hydrogen capacity is 80t distributed in 4 tanks. It will take the Heavy Tug Drone 4 tours to move the 80t fuel to K.G.02 (which is half the K.G.02 capacity of 160t fuel) - and right now K.G.01 only has methalox for 2 tours. before needing to be refueled - 16 M.F.G.V launches.

A part of me wants K.G.01 to have enough fuel to perform all 4 Hydrogen Launches without having to refuel - which means I have to double the Methalox capacity of K.G.01 - there are two solutions to this:

Image of double docking port - and extended methalox tank.

Solution A:

Make double docking port adaptor for K.G.01 - This will double the fuel capacity without changing the fuel tank design. It will probably also look dope AF. But! Every adaptor is 10 parts - and every extra fuel tank is 7 parts. Which means I would be adding. 96 parts to K.G.01 - and it already has a pretty poor performance.

Solution B:

I make a new fuel tank with 16t instead of 8t - It will mean that K.G.01 and K.G.02 will not have the same tanks. - This could be resolved over time though.

What do you guys think? Go crazy and hope for performance improvements - or be sensible and put on less parts/bigger tanks?

 

Any way - detailed walkthrough of the mission in spoiler section bellow:

Spoiler

Medium tug drone performing loading of Methalox to the Heavy Tug Drone.

Loading went far into the dark side of Kerbin. No issues as K.G.01v2 is a well lit environment now.

The heavy tug drone fully loaded and just waiting for an optimal Mun transfer window before undocking. - Notice that the medium tug drone from the heavy tug drone has been stored on the K.G.01 docking arm. This is the last piece of the original station, since it was not present it couldn't break.

And the Heavy Tug Drone leaving K.G.01 now only fitted with 4 empty fuel tanks.

Moving Forward:

Now I will return to K.G.02 for the first time in a while. I hope my experience navigating the buggy waters of KSP2 will spare K.G.02 for any breaking. I will at least do my best for it not to happen.

Next up will be the instillation of what ever solution I find to K.G.01 - as well as escape vehicles for K.G.02, a correction of inclination on K.G.02 and last but not least, crew.

Stay tuned for more.

 

[BechMeister]

////////////////////MISSION UPDATE\\\\\\\\\\\\\\\\\\\\

K.G.02 fully assembled and crewed in orbit around the Mun, overlooking Kerbin.

Mission Tasks:

A. Install the last 4 methalox tanks to K.G.02 - Success

B. Burn K.G.02 into a 0° inclination. - Semi-Success

C. Develop Escape Vehicle for K.G.02 and a new Heavy Tug Drone. - Success

D. Install Escape Vehicles and crew the station. - Success

 

Lessons Learned; Lessons Identified:

A.

All 8 methalox tanks installed at K.G.02

It was quite the journey to get the last 4 tanks installed. I found out that the inline ports are particularly troubled - I installed 2/4 tanks no problem and logged for the evening. When i opened the game next day the "docked but not docked" issue showed its ugly face. I found out that if you load a save where the inline/shielded ports were docked to the drone, it would register the port not as docked, but the two crafts as one. It was quite a mess... 

I also had an issue where the Kraken would strike when ever the drone connected the fuel tank to the methalox tank port. I solved that by aiming the tank at the port and then undock from it while coasting. making sure the drone was not docked to the troubled shielded port when the tank docked to the station. It was a bit harrowing as the fuel tanks are "dumb" so orientation, direction and speed was set once disconnected.

Any way I got the 4 tanks installed. I don't know if I will be using the shielded part on vehicles anytime soon. The Issues does not seem to have been resolved in v.0.1.4 as per the blog. How ever Anth12 has asked me to check if the issue is still there. So I'll test it when I install the now missing 4 tanks to K.G.01 - and I will do some bug hunting trying to put the Escape Gliders and M.L.K.O.s on K.G.01

All bug reports has ofcourse been updated with my findings..

See detailed walkthrough of the process in spoiler section:

Spoiler

The Heavy Tug drone arriving at K.G.02 doing its break burn to match orbit.

When I arrived at K.G.02 Kerbol was eclipsed by The Mun. You can't make these vistas up. Kerbin with the entire atmosphere illuminated and The Mun in total dark made for an awesome backdrop.

The Heavy Tug Drone parked under K.G.02 ready for hand over; take over of the fuel tanks with the small drones. Notice the 4 empty docking ports on the methalox assembly

Small Tug Drone pushing the first new methalox port into position. 

Kerbol peaking from between the mun and kerbin. While the Small Tug Drone picks up tank no. 3

The Small Tug Drone moving tank no. 4 away from the Heavy Tug Drone.

K.G.02 with all the tanks installed.

B.

Heavy Tug Drone pushing K.G.02 into a ~0° inclination to ease future rendezvous from K.G.01

This step turned out to be somewhat more difficult than first anticipated. With K.G.01 I could just set The Mun as target and it would show me where the Ascending and Descending nodes were. How ever I could not get K.G.02 to show me the ascending/descending node when targeting Kerbin.

My solution was to fly the prototype of the new heavy tug drone to The Mun - together with the prototype for the Escape Vehicle to The Mun and be very careful not to stray away from the 0° inclination. This would allow me to test both See section C.

while not perfect - it proved close enough. Subsequent launches with the fully developed escape vehicles show that its still some 0.2° off - but thats so little so I call it a success.

K.G.02 being boosted into a 0° inclination.

The station was easy to boost - the center structure stayed on point and having 8 empty hydrogen tanks rather than full meant that the structure did not experience a lot of stress. I was a bit worried that it would veer off course, as the super structure had "warped/bend" because of uncareful saves. I really wish we did not have to be so careful with saving while a craft/structure is under tension/compression!! 

Later i managed to somewhat straighten out the structure by making strategic quicksaves while the station was orientating towards the sun again and thus flexing... But it is a thing that creates considerable stress to me.. That I need to worry about that when ever I save.

Also K.G.02 has some serious resonance issues. I dont know what happens.. but the station will start to resonate and vibrate so violently that it falls a part. So far the only way to fix this is to constantly swap between cargo and station as soon as its loaded onto the grid and use time warp to stop it vibrate out of control. 

C.

Escape Vehicle on approach to the Mun being tested.

Escape Vehicle for K.G.02:

When developing the escape vehicle I initially tried to make it with 4 engines at the top - like all the cool kids. First try proved that the engines were very inefficient in that position - The craft had 1700 Δv in total, but would spend all of the Δv breaking, and landing because the engines would lose a lot of effect from thrusting into the structure of the vehicle. I think it's very cool the game punish you for not thinking about that... but it would nice if the Δv count and T/W ratio would reflect this.

2nd version I angled the engines out - It would still spend most of the Δv getting down to the surface of The Mun - now because of the inefficient thrust vectors. In the end I decided to scrap the idea of placing the thrusters on top. and put them on the bottom as shown in the image. 

The craft has enough Δv to break itself to a suborbital path with The Mun from 1790 km above the surface and land. It has enough Δv to get itself back into orbit. But not back to 1790 km orbit. That being said - if a rescue mission has to recover the escape vehicle - I suspect it will be a lot easier to do so in orbit. So there is that.

Escape Vehicle Prototype 3 on touch down on The Mun and fully deployed.

The escape vehicle has 2 big solar panels to keep it running while on the surface - waiting for rescue. It can hold 3 crew members. I have made it so that the landing legs will be stiff upon landing. but as soon as the craft has landed it can hydraulic lower itself to rest on the ground. Allowing Kerbals to go for a walk without needing latter's. The craft has a big antenna pointing up for transmitting and receiving big data packages - and a smaller VHF antenna for faster communication with LOS to possible rescue missions. 

Last but not least - it has 4 big spotlights for illuminating the landing zone and is painted red to be easily visible from space.

I may have made one error though - the battery power could be an issue if you are forced to land on the dark side of the mun. - I dont think the battery capacity will last you 6 days  So I guess you can also spend some of the Δv getting to the north or south pole... otherwise there is room for a future scandal when kerbins suffocated because the escape craft ran out of juice before the rescue... to dark?

New Heavy Tug Drone (H.T.D.):

New H.T.D. front and back together with M.K.L.O and Medium Tug Drone.

I tried to make a full version of K.G.01 inside the VAB with the converter that allowed for 16 methalox tanks being installed. It looked pretty cool but lagged insanely much. The bigger fuel tanks did not look good. But it got me thinking that I could make a new H.T.D. with the new vacuum optimized methalox engines and see if I could lower the fuel amount to something sensible.

The new drone carries 18t Methalox - meaning that it will require 2 fuel tanks to refuel instead of 4. With 8 fuel tanks it means it should be able to move the 4 hydrogen tanks without having to refuel K.G.01 in the meantime. Thus synergy has been restored.

I liked the 4 engine look of the labradoodle engine and decided to go for 4 LV-1000 "Cornet"s - it turned out that the mass reduction from using 4 engines also meant I had more Δv - if the game can be trusted. I did a bunch of rocket equations to get the most Δv as possible - but I can't remember what engine config gave the best result (LV-1000 vs LV-3000)

I tried to make the "4 finger" methalox mount to make sense on the H.T.D. But it was just impossible to get the right amount of Δv squished into the design if it had to move 36t fuel rather than the 20t fuel with the hydrogen tanks, and making a "3 finger" 27t fuel tank configuration was impossible to make "pretty". So I have decided to reduce it to a "2 finger" setup - meaning 18t fuel, which is only 2t shy of the 20t hydrogen tank. 

Looking like this:

H.T.D. with "2 finger" fuel mount and next to a standard 20t hydrogen tank

The most important is that the craft is compatible with the M.L.K.O.s and the fuel tanks, and it has synergy with K.G.01 and 02.

D.

H.T.D.v2 enroute to K.G.02 with an Escape Vehicle.

The last step for K.G.02 was to install the newly developed Escape Vehicles and crew it. The journey went without incidents. 

K.G.02 fully operational and crewed. Here with the 4 escape vehicles installed.

I installed the 4 escape vehicles on the lower docking ring as I imagine them only being used in emergency - So you dont want to walk passed them all the time on the "comercial flights" - the upper docking ring will be for M.K.L.O.s and future crew crafts.

Since the M.K.L.O.s are only capable of surviving re-entry on Kerbin, and not a landing on The Mun. I decided to install 4 Escape Vehicles - as the M.K.L.O. can't double as a escape craft for interplanetary ship crews, as it can on K.G.01

Moving Forward:

I suspect my next post to be the last post on this epic journey. K.G.01 needs to have the 4 new methalox tanks launched to it, to replace the 4 tanks I just installed on K.G.02. Then all tanks that need to be in circulation are in orbit. I will also be installing the Escape Gliders and M.K.L.O.s on K.G.01 to see if the inline/shielded clamp-o-tron bugs persist after v.0.1.4

Stay tuned for more!

K.G.02 fully assembled with The Mun as a backdrop

[BechMeister]

////////////////////MISSION_UPDATE\\\\\\\\\\\\\\\\\\\\
- Grid Fins -

The refuel glider, parked next to its first stage after returning from a refueling mission at K.G.01

Foreword:

So.. After 235 hours, blazing from star to star in the year 2330. Uncovering the meaning of Unity and battling the Starborn - I have completed Starfield, and are ready to return to finishing K.G.01 and 02 with renewed vigor. 

First pleasant surprise was the addition of grid fins! And boy do they make the aiming easier. Still have a lot to improve - I especially have a tendency to have a lot of sideways movement on the last few m/s before touch down. But more on that bellow

Without further ado.

Mission Tasks:

A. Test new grid fins and their drag efficiency.

B. Rebalance the 2nd stage glider.

C. Refuel K.G.01 with Methalox

Lessons Learned; Lessons Identified.

A.  I experimented with a few setup of fins. In the beginning I made a setup with 4 at the bottom and 4 at the top. Mimicking the version of the rocket with the airbrakes - the button ones would be open all the way through the thick part of the atmosphere to ensure the drag was behind the center of mass, and then retract them once the rocket - with my rather unconventional design.. wouldnt flip on it self. I would deploy the top pair when  going down.

I Found that the control was still a bit frail. I remembered that SpaceXs superheavy flies with the grid fins deployed to compensate for the draggy starship. Figured if its fins could control the rocket placed center mass - then maybe I could to. 

I tried to fly the rocket with the top pair deployed and I had more control - although its still like balancing a stick on your hand. If the rocket moves much beyond the circle of the prograde marker it will flip. 

On the way down I flew it with the top pair. At one time on the way down I found I had trouble steering it towards the pad. I remembered seeing youtube movie with Matt Lowne where he talked about them functioning as wings. I deployed all 8 grid fins and it almost flew as a plane.

After a few refuel runs were I experimented more with the gliders wings (See section B) I got rid of the buttom half of the fins as I didnt feel I needed them. But missing the pad made me add 2 to the bottom part. Working as front wings to steer it into the pad:

Refuel rocket deploying the 2nd stage, revised glider, showing the 4 top grid finds deployed for stability and the buttom two folded up.

When I get more skilled with the grid fins I may remove the bottom two again.  - I dont know if its just me. but I feel like the grid fins fight the SAS. In the upper atmosphere I feel like inverting the controls on the way down in the thin atmosphere, and then reverse it in the bottom 3rd part. I'm still playing around with it. 

Aiming is the hard part. I wish the game somehow could help us take the planets rotation into account. As of now I aim around here.

1st stage on its way down towards the pads.

As you can see, I placed a little craft on the center landing pad (which I have set as target) to help get the general direction correct - I find extending or shortening the glide is easier than moving left or right.

1st stage safely back on the pad.

The best landing I made during the several refuel runs. I find now that I can land on one of the 4 pads. But its always going to be the most convenient pad on the way down - and I land beside it most of the time x)

See spoiler section bellow for the full walkthrough:

Spoiler

1st and 2nd stage wishing each others goodbye.

1st stage aiming for the pads. Its quite tricky - right now it looks like it will hit the water... or the complex.. but the planet rotate quite fast.

And here we go - the best of the landings right before touch down. I find that I can easier control the decent with 3/7 engines on - how ever.. in a pinch 7/7 can save the rocket from turning into a fireball.

   

B.

Revised Glider making the final approach to K.G.01.

With the gridfins now in game - and the ability to test them. I could revise the gliders wings to help with the drag. I reduced the wings over several flights - until the point where I had two gliders that could not be controlled on the way down - They would do the classic flip once they hit the atmosphere.

The latest iteration sits at a sweet spot: The smallest wings that can give controlled decent - As long as you maneuver within 45° AoA it will not flip. 

Even with the wing reduction It is capable of flying at a ÷20° at around 150 m/s - meaning you have plenty of room to extend the glide if needed. I also found it has plenty enough fuel on to start the seperation at 1800 Δv - insted of 1600 - giving that much more Δv for the 1st stage to land. 

For full walkthrough - see spoiler section:

Spoiler

In the end the final coasting towards the station took a while. I have a weird bug where some times the different RCS thrusters do not work - in this case only 1 of 2 thrusters pushing the craft right was working - meaning I had to be careful on the relative speed. As any corrections right would also yaw the craft.

Even with the issues I succeded in getting it docked in a nice clean way. Not off angle either. I think the Target maneuvering has improved in this patch. I still think it was better in patch 1.2.

Refuel complete - time to release and burn back to KSC

Here is a side view on the way down - It may be hard to see, but the wings are significantly smaller than previous crafts. From 06 to 04 in with.

lining up the run way.

Final approach

Flare before landing.

And touch down.

 

C.  

During the 5 or 6 refueling missions I successfully iron out the kinks and got the vehicle ready for this patch quirks. K.G.01 is now opperational again after moving Methalox to K.G.02 and fixing all the things that broke - I gotta give the developers credits. My frame rate at the station is a lot better now than before my Starfield break.

Moving forward:

Now it is time to get the revised Heavy Drone up and proceed with fueling K.G.02's hydrogen tanks.

I am also going to check if the Shielded/Inline clamp-o-tron is still bugged and make that propper bug report I promised Anth.

Stay Tuned for More!

 

Edited November 21, 2023 by BechMeister

[Bej Kerman]

3 hours ago, BechMeister said:

////////////////////MISSION_UPDATE\\\\\\\\\\\\\\\\\\\\
- Grid Fins -

The refuel glider, parked next to its first stage after returning from a refueling mission at K.G.01

Foreword:

So.. After 235 hours, blazing from star to star in the year 2330. Uncovering the meaning of Unity and battling the Starborn - I have completed Starfield, and are ready to return to finishing K.G.01 and 02 with renewed vigor. 

First pleasant surprise was the addition of grid fins! And boy do they make the aiming easier. Still have a lot to improve - I especially have a tendency to have a lot of sideways movement on the last few m/s before touch down. But more on that bellow

Without further ado.

Mission Tasks:

A. Test new grid fins and their drag efficiency.

B. Rebalance the 2nd stage glider.

C. Refuel K.G.01 with Methalox

Lessons Learned; Lessons Identified.

A.  I experimented with a few setup of fins. In the beginning I made a setup with 4 at the bottom and 4 at the top. Mimicking the version of the rocket with the airbrakes - the button ones would be open all the way through the atmosphere to ensure the drag was behind the center of mass - with my rather unconventional design.. I would deploy the top pair when  going down.

I Found that the control was still a bit frail. I remembered that SpaceXs superheavy flies with the grid fins deployed to compensate for the draggy starship. Figured if its fins could control the rocket placed center mass - then maybe I could to. 

I tried to fly the rocket with the top pair deployed and I had more control - although its still like balancing a stick on your hand. If the rocket moves much beyond the circle of the prograde marker it will flip. 

On the way down I flew it with the top pair. At one time on the way down I found I had trouble steering it towards the pad. I remembered seeing youtube movie with Matt Lowne where he talked about them functioning as wings. I deployed all 8 grid fins and it almost flew as a plane.

After a few refuel runs were I experimented more with the gliders wings (See section B) I got rid of the buttom half of the fins as I didnt feel I needed them. But missing the pad made me add 2 to the bottom part. Working as front wings to steer it into the pad:

Refuel rocket deploying the 2nd stage, revised glider, showing the 4 top grid finds deployed for stability and the buttom two folded up.

When I get more skilled with the grid fins I may remove the bottom two again.  - I dont know if its just me. but I feel like the grid fins fight the SAS. In the upper atmosphere I feel like inverting the controls on the way down in the thin atmosphere, and then reverse it in the bottom 3rd part. I'm still playing around with it. 

Aiming is the hard part. I wish the game somehow could help us take the planets rotation into account. As of now I aim around here.

1st stage on its way down towards the pads.

As you can see, I placed a little craft on the center landing pad (which I have set as target) to help get the general direction correct - I find extending or shortening the glide is easier than moving left or right.

1st stage safely back on the pad.

The best landing I made during the several refuel runs. I find now that I can land on one of the 4 pads. But it is the most convenient pad on the way down - and I land beside it most of the time x)

See spoiler section bellow for the full walkthrough:

  Reveal hidden contents

1st and 2nd stage wishing each others goodbye.

1st stage aiming for the pads. Its quite tricky - right now it looks like it will hit the water... or the complex.. but the planet rotate quite fast.

And here we go - the best of the landings right before touch down. I find that I can easier control the decent with 3/7 engines on - how ever.. in a pinch 7/7 can save the rocket from turning into a fireball.

   

B.

Revised Glider making the final approach to K.G.01.

With the gridfins now in game - and the ability to test them. I could revise the gliders wings to help with the drag. I reduced the wings over several flights - until the point where I had two gliders that could not be controlled on the way down. The glider sits at a sweet spot right now - As long as you maneuver within 45° AoA it will not flip. 

Even with the wing reduction It is capable of flying at a ÷20° at around 150 m/s - meaning you have plenty of room to extend the glide. I also found it has plenty enough fuel on to start the seperation at 1800 Δv - insted of 1600 - giving that much more Δv for the 1st stage to land. 

For full walkthrough - see spoiler section:

  Reveal hidden contents

In the end the final coasting towards the station took a while. I have a weird bug where some times the different RCS thrusters do not work - in this case only 1 of 2 thrusters pushing the craft right was working - meaning I had to be careful on the relative speed. As any corrections right would also yaw the craft.

Even with the issues I succeded in getting it docked in a nice clean way. Not off angle either. I think the Target maneuvering has improved in this patch. I still think it was better in patch 1.2.

Refuel complete - time to release and burn back to KSC

Here is a side view on the way down - It may be hard to see, but the wings are significantly smaller than previous crafts. From 06 to 04 in with.

lining up the run way.

Final approach

Flare before landing.

And touch down.

 

C.  

During the 5 or 6 refueling missions I successfully iron out the kinks and got the vehicle ready for this patch quirks. K.G.01 is now opperational again after moving Methalox to K.G.02 and fixing all the things that broke - I gotta give the developers credits. My frame rate at the station is a lot better now than before my Starfield break.

Moving forward:

Now it is time to get the revised Heavy Drone up and proceed with fueling K.G.02's hydrogen tanks.

I am also going to check if the Shielded/Inline clamp-o-tron is still bugged and make that propper bug report I promised Anth.

Stay Tuned for More!

 

Very nice!

Grid fins cause a lot of drag so for ascent stability you'll probably get more mileage adding control surfaces to the booster. To avoid instability on the way down, you can place the control surfaces so that they're below the CoM on the way up and above the CoM when the payload separates.

[BechMeister]

That is not a bad idea! 

 

although i dont know if i dont mind that extra drag though - the 2 fins near the engines steer it quite well as of now, and reduce its speed to around 250 m/s. Which in turn makes lt very easy to land.

How ever. If i added two control surfaces at the bottom. They can help with stability on the way up, and have the same function as wings on the way down.

 

I guess there is something to experiment further with when the hydrogen tanks, eventually has to be refueled. 

[BechMeister]

////////////////////MISSION_UPDATE\\\\\\\\\\\\\\\\\\\\
- Fueling K.G.02 with Hydrogen -

M.T.D loading the H.T.D. with a hydrogen tank - inbound for K.G.02

Foreword:

So I finally got around to experimented with the shielded/inline clamp-o-tron bug, and produce a report with my findings:

I may have found a way to avoid the bug - I'll test it by installing the M.L.K.O's to K.G.01 and the escape shuttles. We'll see if it works or not.. if so It will perhaps give me a chance to finish both stations to the state I had planned. And maybe even before For SCIENCE! arrives.

That being said, I need to tweak my fueling procedure of K.G.02 - more on that bellow:

Mission Tasks:

A. Fly the 20t hydrogen tank to K.G.02 - Success

B. Swap the full 20t hydrogen tank with a empty tank from K.G.02 - Success

C. Rendezvous with K.G.01 - Failure

D. Install empty fuel tank, refuel and repeat step A to D. - Failure

Lessons Learned; Lessons Identified:

A.

M.T.D. loading the H.T.D. - steady as she goes.

Task A went smooth - The four lv-1000 engines may be efficient - but it takes a good 5min to do the intercept burn from Kerbin to The Mun. I dont trust thrusting in time warp... So there were plenty of time to drink my coffee.

I was rather interesting though - The red line, that indicates for how long the burn will take, was on point. But the burn duration was off. So still I dont fully trust the maneuver planner.. its more of a guide line.

Image shows the different  Δv states of the mission to The Mun, as well as how much the burn timer miscalculated.

The Burn Timer said it would require 918 Δv burn to transfer to The Mun. In reality it required 894 Δv - but it burned longer than the timer calculated. I dont fully trust the numbers and I wonder if I should try make the rocket equation to see how much Δv the H.T.D. actually has when it tugs a load of 20t.

See spoiler section bellow for a detailed walkthrough of the Mission:
 

Spoiler

Image showcasing the H.T.D. about to take the 20t fuel tank. Here the back plate design with the 4 lv-1000  engines is in full display.

Transfer has been completed and the M.T.D. have returned to K.G.01 - The H.T.D. now just have to wait for the optimal window to perform the transfer burn.

The 4 Lv-1000 engines doing the 5min burn to transfer the cargo to The Mun SOI.

B.

H.T.D. has performed hand-over;Take-over of the 20t hydrogen tank with the Small Tug Drone that is about to dock the fuel tank to K.G.02 while another Small Tug Drone is preparing to connect the empty 20t fuel tank to the H.T.D. so it can transfer it back to K.G.01 for refueling.

The rendezvous with K.G.02 had a lot of issues.. For some reasons the SAS just wanted to send the station spinning. I tried to disable all reaction wheels besides the center ones in the main structure tower... No luck, I tried to set a "control from here" to the top and make it aim at the sun.. no luck. The only thing that worked was to disable SAS and then use timewarp to kill its momentum and hope it was stable going out of time warp. 

It's something that I've tried with K.G.01 too - as i recall it, it was the first time I loaded the station in again after new patch. This was also the firs time I loaded K.G.02 in as well, so maybe it's just a bug where it does not know whats up and down first time you load the vehicle/station in after the patch? - I dont know... and I dont have enough that I feel like it warrent's a bug report.

Any way - the hand over take over went smooth - fortunately the Small Tug Drones had no issues moving the full tank into place... and even with K.G.02 shaking a bit I successfully swapped the full tank for an empty and redocked the S.T.D.s (Damn... thats a bad acronym now that I see it..) 

Once the H.T.D. was no longer carrying the load of the fuel its Δv counter landed on these figures:

 

I was hoping it would have been enough to bring it back to K.G.01 - but I would find out that it was not soo. More on that in Section C.

Detailed walkthrough of the process in spoiler section bellow:

Spoiler

The H.T.D taking this stunning photo of The Mun and Kerbin on its final approach to K.G.02

The S.T.D. (I really need to find a better name... problem is that M for Mini wont go.. as it will take the space for Medium... Tiny? T.T.D? Maybe...) preparing to do Hand-Over; Take-Over with the H.T.D. - The moment of truth. If this small drone has enough ompfh to move the fuel tank around. I know the fuel tank has its own RCS thrusters to steer it - but the lack of big reaction wheels, center on mass, still made me worry.

A good picture of the mess and potential disasters that could happen with an station that suddenly had a life of its own.. and multiple fuel tanks drifting about.

the full hydrogen tank aligned and slowly drifting into its socket, while the H.T.D. re-aligns itself to take the empty tank. 

S.T.D. back on K.G.02 and the H.T.D. ready to burn back to L.K.O.

C.

The H.T.D. final resting place, all depleted of main engine Δv and almost all monopropellant - still about 30m/s too fast.

It only took 9 Δv to get out of the Muns SOI - and another 171 Δv to get an intercept path to K.G.01. Which left me with too little Δv to actually complete the rendezvous. I dont know what the most efficient way to return to L.K.O is from The Mun. But maybe I can save Δv by having the correct approach.

I will be able to save Δv on the path to The Mun. Normally I have had a path that just takes me into The Muns sphere of influence - but this time I flew a path that went through it instead of gracing it before falling back to L.K.O. I can possible save enough Δv to perform a fuel transfer without spending too much Δv If I do that.

The reason I did it in a less efficient way this time was that it lined perfect up with a rendezvous with K.G.02 - where If I had opted for a more economical path. It would have taken a few days and orbits around The Mun before an optimal window would arrive.

The Path and fuel stats of the H.T.D. had after the 9 Δv burn to leave The Muns SOI - and the correction burn of 171 Δv to put it on a rendezvous path with K.G.01

I am showing the end state of the Path back to K.G.01 to ask if there is a more optimal way to return that saves fuel? 

D.

H.T.D. flying past K.G.01 with only a 30 m/s difference - all depleted of fuel.

Since the H.T.D. failed to rendezvous with K.G.01 I will now have to send up a Methalox Glider to refuel the drone so it can attempt the mission a second time - this time with all the fuel saving mission changes needed to succeed. 

It is interesting how this was the exact same outcome with the old heavy tug drone - I am planning my vehicles for a level of efficiency I can't provide with my current skills and understanding of the game it seems.

 

 

Moving Forward:

Step 1 will be to save the H.T.D. - I will also attempt to redock the M.L.K.O.s and Emergency gliders with my new understanding of the bug that plagues inline and shielded docking ports. Then Step 2 will be to attempt mission tasks A to D again.

I guess its the perfect time to test the suggestion from @Bej Kerman to swap my bottom grid fins to wings for better performance - Now that I will launch a Methalox glider before I had planned.

Stay Tuned for More!

Edited December 2, 2023 by BechMeister

[BechMeister]

////////////////////MISSION_UPDATE\\\\\\\\\\\\\\\\\\\\\

H.T.D. back at K.G.01 after a succesful refueling mission:

Mission Tasks:

A. Test the updated 1st stage for the Methalox Glider. - Success

B. Refuel the stranded H.T.D. - Success

C. Complete a refuel run with Hydrogen (See Mission Tasks A to D last update) - Success

 

Lessons Learned; Lessons Identified:

A.

 

Video showing the launch of the methalox glider, and return of the first stage.

Experimenting with video editing: 

I wanted to experiment with making movies of my missions in KSP2. - I to see what it would look like if I made the hud smaller and cropped it out of the shot to make it look more cinematic. I then wanted to find a way to introduce HUD elements in a more organic way.

The only issue as I see it is this: You need to film on very high quality to do this and not have it be pixilated. I am experimenting with this as I contemplate celebrating the finished project by making a cinematic showcase of the two stations as well as all the systems that support them... maybe on my more powerful school pc for enhanced graphics.

But I digress.

Comment on the design changes of the 1st stage:

Swapping the lower two grid fins with wings was a good solution. Thx Bej Kerman for the suggestion.

The rocket is more stable on the way out, and I have enough control to aim at the pad. You can actually correct really big errors as it can almost fly horizontally if needed (at least something like ÷ 30-40 °.

Right now I have a lot more Δv than I really need.. But I suspect I can reduce the Δv the better I get at landing.

B.

The H.T.D. returned safely to K.G.01 - After the drone had been refueled and loaded up with another 20t Hydrogen. It was ready to attempt the mission task again, this time with a more conservative Δv consumption in every aspect of the mission.

C.

Note: This section has a lot of spoiler sections with a detailed walkthrough - as a step-by-step guide for myself to be able to repeat the process. Sorry if the section seems a bit bloated.

The refueling went smooth this time - and the H.T.D. returned to K.G.01 with 94 Δv left - a pretty tight margin, Just how I like it.

I was originally a bit afraid that the LV-1000 engines were "too" fuel efficient, in the sense that the fact it took them 5 min to do the transfer burn to The Mun - ment that they were burning the craft 30° off the prograde.

Here is a reference photo of the 30° difference between being on course and prograde.

Maybe it's just because my understanding is flawed? But I imagine that it is not very efficient to burn 30° off prograde to stay on course - a lot of that fuel is spend staying on track rather than pushing the Apoapsis right? 

For a detailed walkthrough of  C(a): See Spoiler section:

Spoiler

I recalled that I had spend a lot more Δv getting to the mun last attempt. In reality there is only 3 Δv difference between first attempt and this succesful attempt

I was very fortunate that a prograde burn put the craft on a perfect intercept path to K.G.02 - Only a slight inclination correction had to be done with RCS thrusters before arriving at K.G.02 and matching orbit - spending 207  Δv when the maneuver was done. 

The craft made it to K.G.02. and the main take away is it arrived at K.G.02, with a meager 78Δv In difference - which translate to a difference of 318 Δv once unloaded with the full tank and loaded with the empty fuel tank.

That then means that the Δv budget to get to K.G.02 and complete the rendezvous maneuver. Is only ~1.094 - 1.100 Δv or so. Otherwise the vehicle will be short of the target. Or that if the vehicle has less than 1.200 Δv when leaving K.G.02 - It needs to top off the tanks first.

H.T.D. doing hand-over; take-over with the T.T.Ds (yes i settled on that name) 

The hand over - take over of the fuel tanks went smooth - and I did not have the same issues I had the first time I came back to K.G.02. That being said, I never turned on K.G.02s SAS - as I was afraid to summon the Krakken.

See detailed walkthrough of  C(b) - see spoiler section bellow:

Spoiler

H.T.D. arrived at K.G.02 

T.T.D01 ferrying the full fuel tank towards K.G.02 - ready to align it to its propper place. While T.T.D02 is attaching another empty Hydrogen Tank to H.T.D. Inbound to K.G.01

After the final adjustments T.T.D.01 is slowly pushing the fuel tank into place. T.T.D02 already docked back at the station.

As stated earlier the mission succeeded with 94Δv to spare. The future will tell if a ~100 Δv margin is enough wriggle room for variations in mission parameters.

I will know once done transporting all of the 6 missing tanks.

To see the detailed walkthrough of  C(c): See spoiler section bellow:
 

Spoiler

Like in the first attempt it took about 10 Δv to escape The Muns SOI.

Another 152 Δv was spend getting the periapsis to intersect K.G.01s path 

Another 4Δv was spend to correct inclination error.

I unfortunately took the screenshot of the maneuver midway through it - I will still be able to reproduce it though. Even though the maneuver planner says it would take 681Δv to finish the burn, It only took 635Δv In reality. - So the Δv counter still not be fully trusted.

The last step was to do a correction burn, so the H.T.D. would rendezvous with K.G.01 - leaving me with 328Δv to kill the relative speed between H.T.D. and K.G.01

the H.T.D. post final burn to match the K.G.01 orbit. The only thing left to do was to RCS thrust the final stretch, and dock to refuel, and repeat the mission. 

 

Final Thoughts:

It was nice to see that the theory was possible in practice. 

I think this will be the last update until K.G.02 has been fully fueled - unless something significant happens.

The end of the journey is near.

Stay Tuned for More!

Edited December 6, 2023 by BechMeister

[Mikki]

This is a very nice and detailed missionreport, the yellow glider is specially well designed. Thank you for the good read and insights! Cheerz!

[BechMeister]

Thx a lot @Mikki! I some times "fear" I go too much into detail. But I have had times were, for instance when I was building K.G.02 and had to go back to use the gliders - I forgot how to get them into orbit most efficient. Then it was nice that I could go back and read how I did haha. 

But yeah.. I did not anticipate It would take this many hours to get the two stations operational. Although A lot of extra time was caused by bugs introduced by v0.1.3. - But i'm glad to hear its not too detailed x)

[BechMeister]

////////////////////MISSION_UPDATE\\\\\\\\\\\\\\\\\\\\\

- Replacing All INLINE/SHIELDED Clamp-O-Tron on K.G.01 -

K.G.01 is having its two crew docking arrays changed for the updated version.

Foreword:

So - I dared to ask Anth if he thought the Clamp-O-Tron Inline/shielded bug would be fixed soon™.  Or if I would be better served by replacing the modules using the ports. The latter was the reply. So I set out to redesign the crew docking port for the M.K.L.O and Emergency Escape Giders.

Because there were no good docking spot for the H.T.Ds I decided to including docking space for them too.

Any way... Without Further Ado:

Mission Tasks:

A. design new docking port without Inline/shielded clamp-o-trons - that can dock the M.K.L.Os,  E.E.Gs and the H.T.D.

B. Design a E.E.G. (Emergency Escape Glider) that does not use the Inline/Shielded clamp-o-trons.

C. Install E.E.Gs and M.K.L.Os 

Lessons Learned; Lessons Identified:

A.

The new docking  array for crewed flight - ready for instalment.

Recipe for the rebuild part:

- 2x TVR-300L small to large tri-adapter
- 6x SP-S12 (small structural panel) 
- 1x TVR-200L small to large  bi-adapter
- 3x SF-125 (the plane cylinder) 
- 1x BZ-52 - radial attachment point.
- 1x Clamp-o-Tron Sr.
- 2x Clamp-o-Tron

Comments on the build:

So - I really wish we had some triangle shapes. I often think that the docking ports look "ugly" when they stick out of parts that are round and I didnt wanna use the box adapter, since I would need to have a small docking port on one side and a medium on the other - I figured a triangle shape would look the best. 

I made it by attaching two small plates in the gaps between the 3 cylinders. I then attacked the medium port to the bi-adapter and that to one side of the 2 plates - pushed it in. On the other side the small docking port was fit to the radial attachement point et voilà! - I now had a new docking module - but with 10 parts more than the original part. 

B:

The  new escape glider with out the Mk2 clamp-o-tron.

Previous I had trouble finding an elegant way to fit a Clamp-o-Tron to the small MK2 cargo bay. Since you could not attach it to a cylinder without it sticking out when closed... and the transition from the Phoenix cockpit to a small plate looked ugly, I had not attempted to make it work before. But as we say in my native language "Distress teaches the naked women to spin" - I dont know if it translates well...

I decided that the cone from small to Micro would make a good transition into the small square plate. with the Clamp-o-Tron on. I then fitted 2 Stratus-V Cylindrified monopropellant tanks - as I really like the look they give on the MK2 clamp-o-tron. I put 4 small spot lights. They give a lot less light than the projectors... which is bit of a bummer. But I no longer need to see the docking port to dock. so its fine. Last was a few batteries and the thing was ready... 12 parts more than before.

C.

K.G.01 back to its former glory. 

As suspected - My PC did not like the added parts count. Its really gone down to a slug.. I think K.G.01 is in the 1-digits FPS. It seems when ever the devs improve performance I upgrade and reach the limit of my pc again.

I have refueled 1/4 hydrogen tanks. Thats 8 launches with the Hydrogen Glider. there are 3 hydrogen tanks to go. meaning 24 launches to go... With this frame rate I may "cheat" and fly up a big load of fuel so I can launch the second half of the Hydrogen tanks. 

The station is also all but dry of Methalox. So that needs to be refueled too.  Besides that there was no big issues to the build and installment of the parts.
See spoiler section for in-depth build montage:

Spoiler

 

 

The first docking adaptor being shipped to K.G.01 - I think the triangular shape looks great in the hard light from Kerbol.

Both adaptors installed - ready for vehicles to dock to them.

The button view - with 1 out of 2 H.T.D. docked.

The arrival of the first emergency glider. I decided to mount them with the engine facing the same way as the H.T.D. - As it then could assist in station maneuvers.

Second glider, gliding into position (badum-tsh) 

The M.K.L.O.s together with the second H.T.D. arriving at K.G.01 (the same config that will move crew to and from interplanetary missions in the future)

Notice the dim lighting - the station and vehicle was in a partial solar eclipse.

And all the vehicles installed.

With 2 HTDs and 2 EEGs installed I figured it was as good as time as any to test them in a station re-alignment role. 

With the relative lightness of the station (now that there was only fuel in 1/4 hydrogen tanks  and the internal fuel tanks of the vehicles) - it had ~1200 Δv between the 10 engines. I disabled the 8 small engines on the struts for fuel canisters - figured they will work in a pinch if the H.T.D.s are not present.

I could fly with all engines 100% and the station would not snatch - flex a bit. But nothing dangerous.

K.G.01 correcting its orbit at - 50% thrust.

I dont know what it is - but the 5 concentrated jets of the Aerospikes looks really pleasing.

 Moving Forward:

K.G.01 is still in the process of being refueled. I dont mind doing the 8 launches / fuel tank it takes to fill a single Hydrogen tank. But docking the glider to K.G.01 with 5 FPS makes even the simplest of maneuver a slug. 

So I may cheat and fly a giant hydrogen and methalox tank to K.G.01 - so its not the refueling part that will kill the program... and then In my head cannon it will just be refueled sustainable with the 1st stages and gliders returning to finish the job.

Stay tuned for more!

Edited December 12, 2023 by BechMeister

[Mikki]

On the topic of framerate, i am running a similar station as you know, and my Kerbals do have issues with connecting to their brains properly... ...my crafts (Severe cases of Morbus Magalomania) are actually bigger in size but the partcount is not that high in fact and its all around well playable with two digit framerates in orbit at the station. I have also observed that having lots of methalox engines nibbles on the frames, and maybe parts like the trussed hydrogen tanks aswell, not to mention dockingports, which you have alot on your station(s).

You are well experienced in maneuvering and rendezvous, which is still quite a feat in this buggy state of the software, i can tell too from disastrous "back to VAB"s or launchpad, it just tend to ignore all the apocalyptic events...

Maybe try some of the new parts and declutter your stations, and keep the partcount low as possible? Your designs are awesome btw, nothing against your choice of yeeting Kerbals to space!

You mentioned somewhere my monoprop station tug, i use this craft since KSP1 many years ago and it is truely a truck, works even with half of the thrusters operating . Cheerz!  

AAAAH.... 2k likes!  OMK (Oh my Kod) 

Edited December 13, 2023 by Mikki
Typos:) the likes:D, rendezvous, sorry french peeps

[BechMeister]

13 hours ago, Mikki said:

I have also observed that having lots of methalox engines nibbles on the frames, and maybe parts like the trussed hydrogen tanks aswell, not to mention dockingports, which you have alot on your station(s).

This was good intel - I decided to send the two H.T.Ds into a parking orbit that intersects K.G.01 - Framerate already got a lot better! 

That docking ports etc. kills framerate is not something I think I will be going to address... Part of what I enjoy is figuring out how to build things piecemeal. Not to throw any shade.. but I've always disliked the huge impossible rockets people use to get impossible crafts into space xD - Hopefully with the colony feature, which I recall will have a space station builder too. We can build crafts in space so we dont need to make crazy impossible rockets to get complex things into space.. like the giant spherical hydrogen tanks.

13 hours ago, Mikki said:

You are well experienced in maneuvering and rendezvouz, which is still quite a feat in this buggy state of the software, i can tell too from disastrous "back to VAB"s or launchpad, it just tend to ignore all the apocalyptic events...

Well You do have ample of time to consider your options with 15 fps though xD - There has been a few times were I approached a station too fast.. and had enough time to figure what way to deflect to avoid hitting the station xD

But yeah! I've come far since I started.. I still wish we had the same docking information as in Flight of Nova:

or at the very least I wish that when we go to "target" mode on the HUD - that it would show distance to target, not the ground... there is a lot of quality of life changes I would like..

Like a HUD for flying over the planet at night that could show the outline of shorelines etc.. or at leas the runways. The ability to double click on the navball and have the SAS turn towards that area... maybe I should pile my suggestions into a new post.  

[Mikki]

9 hours ago, BechMeister said:

Snip... but I've always disliked the huge impossible rockets people use to get impossible crafts into space xD - snip

I totally agree with this, i am growing a deep, undisputable, relentless discomfort with the  Kerbals who run my space program. They force me to launch all their stupid stuff without my consent, but what else can i do? I cannnot handle all those random brainless vegetables alone, therefore i seek help in threads like yours! 

Let`s hope for more content and reason in the next update, i need hinges, robotics and snacks at some point.... and the ability to fire the most stupid Kerbals on the spot if they won`t conform to more reasonable actions. Yes.   

[BechMeister]

////////////////////MISSION_UPDATE\\\\\\\\\\\\\\\\\\\\\

- Designing Heavy Tanker Vehicle -

The certification launch of the new Heavy Tanker Vehicle.

Foreword:

Boy do I have an update for you guys. So I wanted to get both K.G.01 and K.G02 fully fueled before For Science landed. 

How ever - I was too late. Finding a more efficient vehicle for refueling took a lot of development time and resulted in many dead ends. Until I figured super sizing it all was going to be the way forward! 

Bellow you can read about how my first XL rocket came to be.

Mission Tasks:

A. Refuel K.G.01

B. Develop new Heavy refueling vehicle.

Lessons Learned; Lessons Identified.

A.

The still glowing engines of the Hydrogen glider - as it slides into the pitch black shadow of Kerbin.

I was well underway to refuel K.G.01 - It took 8 launches to fill 1 tank with Hydrogen. Which would mean 32 launches in total. I do like flying my little gliders - I suspect the Hydrogen glider is lighter than the Methalox glider - or the center of mass is better distributed. It usually has 100-200 more  Δv than the Methalox glider upon mission end. Which means  a more steep re-entry. It is a lot easier to line up the runway when you dont need to guestimate its position 1/3 of an orbit back - but you can do it 1/4 or less.

How ever - Lets address the elephant in the room: 32 launches for Hydrogen. On top of that.. the Methalox come.. to enable refueling K.G.02. And with 1 digit frames pr. second around K.G.01 - It meant each launch took for ever to complete... Not because it was complex. But because the final maneuvering with RCS thrusters easily could take 30 min because everything was going in slowmotion - and the stations/sas had been wobbly ever since 0.1.4.

Something else had to be made. The tours had to be reduced. Which is the perfect segway into the B section of this blog. But first!

Detailed Mission Walkthrough In spoiler section:

Spoiler

 

The Hydrogen M.R.G.V. being fueled - ready for launch.

 

The vehicle majestically moving up. God I love that vehicle now.. One of my best designs.

The glider correcting orbit to match K.G.01

Refueling done.

Final approach to K.S.C.

It is funny how the Methalox glider keeps the stack separators - and the hydrogen dont. I dont know which look i like the most.

In the end I refueled 1 hydrogen tank - before deciding "I was going to need a bigger boat".

 

B.

This endeavour would end up taking the entire week to get right. I was going down 2 paths - The first ended up being a development dead end.

Prototype Heavy Tanker Vehicle A:

Test run of Prototype H.T.Va

I started by trying to design around the 8t hydrogen tank (size L) - it would fit with the launch rocket - I also discovered that I can land the rocket with 1400 Δv now that I have gotten better, rather than the 1800Δv I needed when I started. 

I tried multiple engine configs - 1 vacuum optimized engine and 3 atmospheric for landing. Or 3 vacuum optimized engines of different kinds and 1 atmospheric for landing. But No matter what I did it would never have enough Δv to get to orbit, refuel, de-orbit and land. It would always fall short of having enough Δv to land..

I therefore decided to try turn it into a glider:

I really dont like the esthetic of the transition from L to M parts. Not only did I find this iteration extremely ugly - but no matter what engine config I gave it. It was to heavy for the 1st stage to get it enough speed before seperation to even get to orbit. It was a development dead end.

It also glided like a brick. You would need to approach KSC at ÷45° - which would give you 160 m/s - just enough to flare up and land without exploding.. but a maneuver that demanded perfect timing.

For a time I was contemplating giving up and just going ahead with the 24 missing hydrogen launches... But - reading that Starship will have a payload capacity of 100-150t! (which is insane!) and Arianne Groups S.U.S.I.E. will have a payload capacity of 7t (easier to emulate) - I decided I had to be able to do better than 2.5t Hydrogen 4t Methalox. There was nothing else to do than go XL! Which also allowed me to use the much more esthetic pleasing XL cone.

Prototype Heavy Tanker Vehicle B:

Proof of concept launch of Prototype H.T.Vb.

I did a proof of concept run with the first heavy iteration of the Heavy Tanker vehicle. I decided to use 2x 48-7S "Spark" engines to flip the 1st stage, rather than reaction wheels and RCS - since there are no XL reaction wheels?! - Any way - besides the action group shenanigans I had to do to be able to turn off the main engines and the flip engines on - and reverse. It works great! 

The 1st stage has 3x medium RE-M3 "Mainsail" - providing the main thrust, and 4x S4 KS-25 "Vector" giving the vehicle gimble. An action group has been made that turns off all engines but 3x KS-25 for landing. The first vehicle had 2.200 Δv when stack separation occurred - which meant that I reduced it from 2x S4-51200 fuel tanks - to 1x S4-51200 and 1x S4-12800 tank. 

I tried to fly the prototype to 1800 Δv and could not get it back to KSC. I then discovered that what's important is "not" the Δv left. But it seems the angle and speed is what decides if you can get back or not. If I engine cut at 1000 m/s ~30km altitude  and 45° (same spot stage separation occurs with the M.R.G.Vs) - you will have enough Δv to get back. 

It is very interesting. When the M.R.G.V.s stack separate and returns. Their Δv value is on 1800 - when the H.T.Vb separates - its on 2.300 vΔ 

Second stage Prototype H.T.Vb en-route to K.G.01 with 10t Hydrogen.

The second stage consist of a payload of 10t Hydrogen and is fueled by a single S4-12800 methalox tank totaling at 64t Methalox. Powered by 3x S4 KS-25 "Vector" engines it gives it a total of 2728 Δv - more than enough to get into orbit, rendezvous with K.G.01, de-orbit and land at KSC.

When the decision came to place the docking port I was figuring out how much fuel the rocket would have at the point of contact with K.G.01 - So I could place the port center of mass. One of the more annoying things with the M.R.G.Vs is that the port is not placed center of mass. Which makes docking a bit more annoying... I realised that I did not need to place the port on the side of the rocket. With the XL engine plate. there was both room for the docking port and the engines - and now no matter the fuel level.. the docking port will always be on the center of mass on that axis.

Protype H.T.Vb docked at K.G.01 transferring its fuel load.

The docking was pretty tough - the RCS thrusters was not placed optimally.. also In patch 0.1.4 I often had RCS thrusters that wouldn't work - control surfaces that wouldn't work.. and some times even landing gears that refused to extend.

After shedding 10t the vehicle ended up with 1373 Δv.  When doing the de-orbit burn I made sure to give myself ~400 Δv for a soft landing back at KCS.

Protype H.T.Vb landing some odd 10km from KSC

I landed the vehicle successful - there were some control issues on the way down - but without re-entry heat I didn't know if it would be an issue. I would find out soon!

Now I just have to figure out where to aim to get to the right spot above KSC so I can re-enter nose first and then flip to land.

 

With the proof of concept complete - It was time to make the final adjustments, give it a sleek paint over:

The final version, and fully certified H.T.V. - 2nd stage and 1st stage.

I would still have one single design blunder to correct. Because I did not think about re-entry characteristics I placed the Methalox tank at the bottom of the stack, and the Hydrogen tank on top. Which was all well and good until I had to re-enter. Even with all the control surfaces deployed - there was not enough drag to have it not flip its unprotected rear to the friction of re-entry.

In the end the docking port would be the achilles heel:

Notice the heat level of the exposed docking port.

Even if the vehicle made it through the fiery part - the heat still build up to the point were the port would cause total vehicle failure.

It was an easy fix though - flip the tanks around and it could re-enter nose first even with the control surfaces retracted. - Mission was completed!

Now instead of 32 launches to refuel the 4 Hydrogen tanks - 8 is enough... and with the now improved performance I should get that done in no time!

For detailed mission walkthrough See spoiler section bellow:

Spoiler

All engines go on the way up - It is very pleasant to fly a stable vehicle for once. Not having to fear getting more than 10° out of the AoA is a welcome change.

right before engine cut - I really like the look of the engine plumes within the big main engine plumes.

engine cut - the blue of the atmosphere together with the glowing red engines - i really like that colour contrast.

 

Both flip engines and 2nd stage main engine firering up.

1st stage returning to KSC.

Lining up a landing pad. After the update - the grid fins has really become easy to use!

gentle touch down.

et voilà!

2nd stage continuing into orbit.

matching orbit with K.G.01

approaching the docking tower - the heavy vehicle is still very cumbersome to control. But I have for once matched the amounts of Monopropellant you need perfect. It has just enough to finish the maneuvering.

and docked!

vehicle ready for the final test - re-entry - now with consequences!

I really dig the new effects.

at this part - the vehicle starts to have stability issues and is very difficult to keep on track.

as mentioned - the vehicle flipped and would result in total vehicle loss over KSC.

an updated version with the order of fuel tanks flipped was subsequently launched.

I must really applaud the team. docking has not felt so good since 0.1.2! And look at the Monopropellant levels - perfect.

Refueling complete!

second try! - The fact that It now didn't need to re-enter with the control surfaces deployed - meant that aiming it at KSC was a lot easier. Since the added drag did not shorten the approach.

That being said...

I still missed KSC by a long shot. I think the approach I'm going to try now is to bleed the speed off above KSC - because as soon as you get through the fiery parts of the atmosphere - the vehicle drops speed fast! 

Landed on the wrong side of the ridge Aaand... Those big landing legs - they really dont like the tiniest inclination. I wish they were better at keeping the vehicle level - just bend the joints more? - I fear what this will mean for landing on other bodies - were it isn't 100 leveled.

 

Moving Forward:

With the new vehicle designed - and the number of tours reduced. I suspect fueling up K.G.02 will take no time now.

Giving me just enough time to get used to heat mechanics before going on to duna and beyond!

 

[Sylvi Fisthaug]

7 hours ago, BechMeister said:

Second stage Prototype H.T.Vb en-route to K.G.01 with 10t Hydrogen.

I am astounded that you haven't tried to launch like 150 tonnes to orbit in one single go yet, and just 10 tonnes a launch!  I think the first thing I tried to launch was 50 tonnes, then I tried 100 tonnes, I am to impatient. 

Have you tried the science mode yet? I am finally back in the KSP2 loop, and it is all I wanna play right now! 

[BechMeister]

1 hour ago, Sylvi Fisthaug said:

I am astounded that you haven't tried to launch like 150 tonnes to orbit in one single go yet, and just 10 tonnes a launch!  I think the first thing I tried to launch was 50 tonnes, then I tried 100 tonnes, I am to impatient. 

Have you tried the science mode yet? I am finally back in the KSP2 loop, and it is all I wanna play right now! 

I mean the second stage uses 64t methalox to get the 10t hydrogen into orbit and land the 2nd stage again xD So it is heavier than 10t - I think its hard to make vehicles that can launch big loads of hydrogen as its density is so low.

I have launched heavier payloads - but never with a reusable craft  - also I am more drawn to making "realistic" vehicles rather than crazy big ones. I enjoy figuring out in how many packages I need to ship something.

I have not tried science yet. I am still finishing up this station (SO CLOSE!!) - and then Ill start visit other bodies in KSP2 with the stations I just made. Any way welcome back to KSP2!

[BechMeister]

////////////////////MISSION_UPDATE\\\\\\\\\\\\\\\\\\\\

- K.G.02 Fueled up and Ready -

K.G.02 - fully operational and with its new heat shield installed.

Foreword:

So I wanted this to have been the last mission update on this blog. But to much, I had to document, had happened.

With the introduction of re-entry heat a few more lessons learned; lessons Identified presented themselves. The Kraken also reared its ugly face.. or its been doing it for a while, I just got fed up with putting up with its shenanigans. Which meant K.G.02 had to get a facelift.. and I had to make my most KSP'ed rocket to date.

More on that bellow.

 

Mission Tasks:

A. Iterating the H.T.V. and refueling K.G.01

C. Refueling K.G.02

D. Refitting K.G.02 with a new heat shield.

Lessons Learned; Lessons Identified:

A.

The H.T.V. v1.1 successfully landed at KSC - notice the 3 big grid fins has been replaced with 3 wings

Problem 1: Hitting the mark:

I had a lot of trouble figuring out where to aim my decent point to successfully land the H.T.V. on the pad. Taking Kerbins rotation into account, the time it takes to get to the ground, as well as the bleed of speed going through the atmosphere.. made it really hard to nail the very precise point I had to be to be able to line up the pad.

Right now the H.T.V. will be through the hot re-entry at ~15.000 km altitude. Which means that there is not a lot of time to do the final maneuver that aims it to the pad... and as if that is not bad enough, the fact that it steers like a brick, means that you need to be close to right above the pad to be able to hit it. All in all it means it's practically impossible to hit the right spot. Of the 8 launches it took to refuel K.G.01 with Hydrogen - only 1 landed at the pad. And I feel that was more luck than skill.

I had to find a way to quickly bleed the horizontal speed once it was through the dangerous part of re-entry. - the answer became fitting the vehicle with aerobrakes. I found out that if I aim about here:

 

I will bleed out of the hot part of re-entry right above KSC - by reserving some Δv to extend or shorten the prograde I can aim for the back end of the big island east of KSC once I hit the 70km mark. making sure I consistently have the right path etc. The H.T.V. only needs 300Δv to land - 400Δv to land comfortably with my skills.

Once through the dangerous part of Re-Entry the aerobreaks can engage:

Methalox H.T.V. v.1.2 breaking to line up the run way. 

The image above roughly shows the break out point. From here its all about breaking the vehicle down to 200-300 m/s and then flip the ass - I've found that If i flip it too soon, it will tumble and you spend a lot of altitude getting it back under control you could have spent aiming.

The final iteration of tht H.T.V. also had the stabilizer wings replaced with control surfaces - to enable it easier to "glide" towards the pad.

Problem 2: "Huston we have a problem - My engines are gone"

Picture of the 1st stage of the refuel gliders - and all its engines dropping to the ground.

The second problem I ran into was that the engine plate on the 1st stage of the refueling gliders could only handle re-entry speeds at sub ~700 m/s. I was very worried that this would mean a total redevelopment of the 1st stage. Fortunately I have become so good at getting it back to KSC that I found I could afford to burn the engines and keep the vehicle at around 700 m/s the Result was this much heat:

1st stage of the glider succesfully getting through the thinner atmosphere.

As you can see, I have still plenty of Δv to land the vehicle - and the engines to do it  

Se detailed slide show of Mission Task in Spoiler below:

Spoiler

This was the only version of the original H.T.V. v1.0 that stuck the landing. Notice that the vehicles has been fit with stabilizers to help the 2nd stage control its decent after the 3 big grid fins were removed - also the silver band between the 1st and the second stage, this was a depleted heatshield to make sure the engines of the 2nd stage did not burn the drone section away from the 1st stage - making it dumb, on stage seperation.

Successfully docked and refueling K.G.01 

Hot re-entry.

Looking good - at this point there is no control of the vehicle - if it flips at this point the vehicle will disintegrate and it only just have enough fuel to stick the landing.

performing the flip maneuver.

aiming for the pad

landing. - this would be the only succesful pad landing of the H.T.V. v.1.1

To complete the refueling mission a single launch with the Hydrogen Glider was necessary to top up the last tank. I was really looking forward to see the glider go through the atmosphere.

Unfortunately the  glider had such a gentle re-entry that it never got hot - bleeding off all the energy bouncing off the atmosphere and then re-enter at 400-500 m/s. - so no pretty pictures of re-entry flames on the glider. But I can offer this instead:

The 1st stage back at K.G.01 - lit by the sun setting. The graphics has really become pretty after this update. I really love that you can see the shadow of the planet in the horizon.

1st of 6 Methalox H.T.V. 1.2 enroute to K.G.01 refueling the Methalox tanks. Notice that I have done away with the heat shield between stages here. Also to help the 2nd stage glide a bit, I replaced the dumb wings (stabilizers) with actual control surfaces - It gives it some "glideability" when aiming for the pad.

Here it is docked and unloading its cargo. I decided to extend the docking port - so it sticks out the bottom with 2 reaction control wheels. It makes the vehicle less cumbersome to move - and the engines dont hit the docking tower at off angles. The vehicle also had a total re-design of the RCS thrusters.

Hot re-entry

Breaking the vehicle down so it gets a steep path down instead of a flat path.

lining up the pad. - this is the best glide angle the vehicle can get. Not good but good enough.

gentle gentle does it.

B.

Two H.T.D.s each pushing 20t hydrogen into a lunar insertion orbit.

The next part was pretty "simple" Continue the fueling up of K.G.02. Since I had 2 H.T.D.s this time I decided to try launch them simultaneously. It demanded an unnecessarily load of work to do this. Even if a vehicle as 0 m/s relative motion to each other - they can still drift several kilometers away over the wait time.

The first time I did not realize I could connect the two vehicles while they were coasting. (significantly reducing the workload) Second and final load I connected the two vehicles every time they had done their burns. Although I know it makes sense - It has hard for my brain to wrap around why the  Δv is almost halved when the two vehicles are connected - compared to them being separate  The rocket equation is wild.

Any way - I cannot figure out if it was worth the extra hassle. On one side its nice that they arrive at K.G.02 at the same time - I remember building the station that It could be really situational how quick things could arrive at the station. Since if you have a bad insertion window you need to orbit the moon a few times before you get a good rendezvous... but that takes month around the mun. SO I avoid that hassle... but I have to time the maneuvers - kill relative speed after each and connect the vehicles again to avoid drift - also took time to do. 

That being said - man it looks good.. but it puts a lot of Sci-Fi epics in contrast. It must be hella lot of work for fleet ships to stay in formation in real life. xD

Se detailed slide show of Mission Task in Spoiler below:

Spoiler

Images of the Insertion Burn to the Mun - I dont know why but it looks so appealing to me to have multiple vehicles fly in formation.

The two tanks arriving at K.G.02

The Tanks are being swapped - you may notice the Kraken problem . I found out that the solar panel arrays was prone to Kraken Attacks. I decided to replace them with something else (See Section C for that) - trying to manage wobbling via the time warp tool and juggling multiple vehicles became too much in the end.. so I just allowed the panels to break off.

I swapped the tanks one at the time - only 2 T.T.Ds to do the work - although that being said.. Doing 4 T.T.Ds moving tanks to and from the station to 2 H.T.Ds is not an act I would like to attempt. 

H.T.Ds enroute back to Kerbin. Looks so good!

fine tuning the rendezvous with K.G.01

H.T.Ds returned to K.G.01 - It was perfect! One of the H.T.Ds returned with 10 Δv in the tanks. I was worried that me fiddling with the tandem flying would spend more fuel - it did.. but not to much.

The H.T.Ds refueled and being loaded with another 20t tank by the M.T.D.

H.T.D. returned to the Mun SOI.

I love seeing the two vehicles break - It reminds me of the scene from Avatar 2 where the ISVs do their break burn arriving at Pandora. Also here we can see the new "heat shield" on K.G.02.

Here a view of the two vehicles breaking - showing the heat shield from above and with The mun as a back drop.

The T.T.Ds starting to do work.

K.G.02 fully fueled, crewed and opperational.

C.

The problem that had to be solved.

So - K.G.02s solar panel array was prone to Kraken attacks. It would start to vibrate until the point where it would break itself a part. I could manage it by hitting Timewarp for a second.. but It happened so often that I would have to reload a previous save multiple times because the station had broke apart while I looked away:

I decided that I would have no more of it and looked at alternatives - The only item that was able to build the shape I needed without having a bazilian parts were wings. So.. this is also my first alternatives use of wings as well as my first ridicules rocket.

Behold this monstrosity:

The stand-up guy of a rocket needed to get the new heatshield into orbit - I so look forward to be able to build stuff like this in space.

Since the heatshield had the structural integrity of a wet tissue paper, and the drag of a drag coefficient of a pavillion at a Childs' birthday party, It meant that I would have to drag it into space instead of pushing it (Tensile strength vs compression) - I also had to launch it at 45° E as soon as it cleared the tower - because once it had gained speed, you could not do maneuvers without it breaking apart...

The heatshield fighting its way through the atmosphere - powered by 4 massive solid rocket boosters.

As you can see this maneuver made for a quite hot tour over the karman line. While in the atmosphere the rocket was powered by the 4 biggest solid rocket boosters I could find. The biggest challenge was completed - getting it into space.

After it was just gently installing it on K.G.02 - Since it was quite big the T.T.Ds had a lot of "trouble" rotating it to the right angle. It was easier to rotate K.G.02 to fit the correct orientation. 

The result was this:


K.G.02 with the new heat shield installed.

K.G.02s Hydrogen tanks are now shielded from Kerbols rays propper - so propper that I actually wish I had installed a few flod lights to it. It's very dark in the shadow now. But maybe that can be remedied in the future once we need to install radiators to our vehicles and stations.

Se detailed slide show of Mission Task in Spoiler below:

Spoiler

The heat shield right before engine shutdown on the solid rocket boosters.

Stage separation.

Now that the rocket was out of the atmosphere I could drop the tail and engage the atomic engines. Although I really dont like ridicules rockets like this.. and wish I could build stuff like this in space. But I must say i like the look of the 6 small atomic engines in this config.

The tug crashing itself into The Mun while T.T.D is gently pushing the heatshild into place. As you can see it is dwarfed by the heatshield. SO its single small reaction control wheel had a lot of trouble turning this big thing around x)

The  new heat shield being carefully mounted to the station.

 

Moving Forward:

Last thing to do now is just refueling K.G.01 again and it is finally over. Then I will upload the craft files to all the vehicles, station parts etc. Its weird to think that it's soon over. But I feel like I have also build more like 3½-4 stations rather than 2 stations at this point... as well as developing each service vehicle 3 or 4 times before getting it right. I have learned a lot with this journey.. and I am looking forward to break free of Kerbin.. Maybe i'll take a tour to Minimus first just to square off Kerbin SOI.

Any way!

See you next time, hopefully for the last time x)

 

[Icegrx]

Okay, I had to make an account on the forums just so I could post on this thread. 

“See you next time, hopefully for the last time x)”

Man, you better continue this mission or hopefully start a new thread! I started reading your posts a few days back and just now finally caught up to the current post. I’ve been tuning in here as I play KSP2 for the first time after many hours of KSP1. These posts offer a ton of inspiration, guidance and just great amusement. I cant really stomach watching “let’s play” videos anymore however the style of these posts have been fantastic! 
 

I haven’t really copied any of your vehicle or station builds, as I like to build things from the ground up and test on my own, quite like you are doing! I have copied many of your philosophies though. In KSP1 I would build these single vehicles that had many uses. They would end up large, and a lot of the times plain ugly or inefficient at certain tasks. I have taken to your “many vehicles with specific tasks” approach now. Color coding everything and trying to make launchers and stages as modular as I can. Trying to be as much like a “real space program” as I can be.
 

I’m having a fantastic time learning KSP2 and following along with your journey as I do it. 

keep it coming! 

 

[BechMeister]

12 hours ago, Icegrx said:

I started reading your posts a few days back and just now finally caught up to the current post. I’ve been tuning in here as I play KSP2 for the first time after many hours of KSP1. These posts offer a ton of inspiration, guidance and just great amusement. I cant really stomach watching “let’s play” videos anymore however the style of these posts have been fantastic! 

It is words like these is whats keep me going with this project - Its the motivation that allows me to "waste" an entire evening on a development dead end, and then write a lengthy post about it! So thank you for the kind words. 

"Blogging" like this often feels like you are sending up smoke signals without knowing if any one is watching x) Of course I wouldn't do it if I didn't like it... But it is very nice to hear that the level of details I go into is appreciated (especially as I've often feared that I am overstaying my welcome) So thank you for taking the time to read my blog 

12 hours ago, Icegrx said:

Man, you better continue this mission or hopefully start a new thread!

Dont worry! This form is going to be a main stay for my projects I think - I will update this thread when its relevant. I foresee an update when radiators are implemented to the game. But the overall goal of this Mission was establishing K.G.01 and 02 - making them operational and design the needed infrastructure to run them. And the only thing that's left is fueling K.G.01 up again.

I was suggested by @GalileOh-No to do the Duna Mastery challenge, which I will be doing after a small trip to Minimus so I can square of all bodies in the Kerbin SOI.

That being said my small minimus mission vehicle has grow to a ridicules size - I've had a lot of fun in the VAB making truly huge vehicles, not taking my PCs performance into account... More akin to a Interplanetary vehicle - probably capable of a Jool's Moons Mission. So I will probably make a new scaled down version for the Minimus Mission (More on that in its own relevant thread).

I can see The Duna Mastery have its own thread in the style of this one.

But again, thank you for the kind words! It fuels me with motivation to continue crunching problems, creating synergy etc.  

Edited January 13 by BechMeister

[BechMeister]

////////////////////MISSION_UPDATE\\\\\\\\\\\\\\\\\\\\

H.T.D.01 and H.T.D.02 enroute to K.G.01

Foreword:

So. I have been taking it a bit slow refueling K.G.01 - The two H.T.D. were 6 days from their maneuver node, and rather than timewarp I spend the days developing the vehicles for a Minimus Mission - which I will do as my first mission after this. Maybe a permanent Mun settlement too? Who knows.

Any way - I was well under way with refueling K.G.01 When I ran into another Issue... a reoccurring issue. The glider is off balance again. I decided to upload the current process on the refueling, before going into re-re-re-redevelopment of the glider.

Mission Tasks:

A. Return the two Hydrogen Tanks from K.G.02 to K.G.01

B. Refuel K.G.01 with Methalox

C. Refuel K.G.02 with Hydrogen

Lessons Learned; Lessons Identified:

A.

H.T.D.01 and H.T.D.02  arriving at K.G.01

This step went without issues - I found that its really "easy" to send two at a time by using the "connect the two drones" after each maneuver and "disconnect the two drones" before the next.

The added time it takes to connect/disconnect and co-ordinate prograde and burn timer + timing the actual burn  and kill relative speed afterwards is worth it. Not only for the aesthetic of seeing the two vehicles flying together. But also making sure that the rendezvous goes smooth. Especially around The Mun it can take weeks to rendezvous with K.G.02 because of the slow orbit... and you can easily end up juggling multiple vehicles rendezvous - as seen when building K.G.02, were some of the first parts to arrive were the last to be connected due to a bad transfer window.

It has also, technically, reduces the amount of tours from 4 to 2. The only negative is it uses a lot more monopropellant than if you send them individually. 

For detailed walkthrough see spoiler section bellow:

Spoiler

H.T.D.01 and H.T.D.02 performing a breaking burn to insert themselves to a LKO

M.T.D. performing hand-over; take-over with the H.T.D.

M.T.D. docking the 1st empty Hydrogen tank to K.G.01

H.T.D.01 and H.T.D.02 docking to K.G.01 - H.T.D.02 in black silhouette against the Kerbin Atmosphere. 

H.T.D.01 and H.T.D.02 docked at K.G.01 just in time to be graced by the orange rays of the sun piercing the atmosphere.

K.G.01 ready to be refueled.

B.

Methalox H.T.V. enroute to K.G.01 to refuel the station. 

The time had come to the last step before both stations would be fully operational - fueling up K.G.01

How ever when I was going to load the vehicle file of the Heavy Tank Vehicle... It had disappeared? I dont understand how.. I must have accidently deleted it when I cleaned up my work files for vehicles. Luckily this blog aided me immensely in reverse engineering the vehicle quick. All the way from what parts to spacing etc.   

By looking at the images I had the rocket down again in a 20 min time - and by 2nd refueling mission the wings, grid fins and aerobreaks had been "balanced" on the 2nd stage, so the vehicle would fly nose first through the atmosphere again.

While I was doing the refueling missions (I did 1-2 launches pr/afternoon) ESA successfully launched the Axiom 3 mission to ISS. 

On their Facebook profile they showed this simplified explainer on how dragon reaches ISS:

I thought it was very interesting that they would take a 7.5km lower orbit than the target and then burn to intercept it when they were right "beneath it".

I have always done an approach were my Apogee is + ~60-80km of the target Apogee and the perigee is +/÷0km to the target perigee - and then I just waited for them to intercept-ish and then correct the last by either burning  Radial In or out. 

It can be very situational how many orbits it takes for this to happen - and depending on how lazy you are, it's a vastly different amount of  Δv used for the last correction burn.

With the ESA Dragon approach, it is very easy to make sure you spend the same amount of Δv pr. Mission as you remove the last step with fine tuning the rendezvous burning radial In//out.

The most interesting things to find out would be this: How much Δv is saved by doing this? and how long time does it take to catch up to/wait for the target to catch up, doing this?

As you can see I adopted a ~10km lower orbit than K.G.01 which is currently orbiting at a 98 -102km orbit or so. It resulted in me being 12.5km away from the target when I was directly below it.

It actually goes surprisingly fast with catching up to the target. The furthest I was away from K.G.01 this time, was a time were I was on the uppersit side of Kerbin than K.G.01 after I reached my target orbit. It took 1  Kerbin day to catch up to K.G.01 - which means that It will never take more than 2 days to catch up to the station.. presuming that you reach orbit at the worst possible moment.

As you can see the vehicle had Δv 1460 Δv left (the number is actually lower, as the craft is counting the cargo of 12t methalox into its Δv amount) The Prograde burn to catch up with K.G.01 is only 10 Δv and some fine tuning with the RCS thrusters as seen here:

I dont have exact numbers - but this maneuver, on average, definitely goes faster time warp wise (it is slower to perform as you need to be more precise with managing your PE/AP) and I think I save somewhere close to 200-300 Δv compared to my old method.

The refueling went fine with H.T.V. and the last load of methalox would have to be supplied by the Methalox glider.

For a detailed mission walkthrough for the H.T.V. See spoiler section bellow:
 

Spoiler

H.T.V. docked to K.G.01 over the deserts of Kerbin - Soon the vehicle reaches the maneuver node for its deorbit burn and will detach from K.G.01

H.T.V.  re-entering the atmosphere over K.G.01

I have found the most effective way to line up K.G.01 is to make a 300Δv deorbit burn - where I aim for a spot in the ocean that is double the distance from KSC to the islands east of the coast. Once the vehicle hits the 70km mark - I will spend the last 200 Δv to aim for a spot just north of the island eastern coast. Most of the time it means the vehicle goes sub 1000 m/s over KSC. Which is important as it can only fly 10° of a free fall and 20° the last 8km or so... SO you have to be pretty much above to hit the mark.

H.T.V. applying break's to bleed off horizontal speed.

H.T.V. lining up the landing pad

Slowing the vehicle down for a gentle landing.

the 3 leg configuration is very "fragile".. and prone to falling... I really dont like the LT-3 Wallaby legs.. but unfortunately it's the only thing we have that can extend beyond the engines.

H.T.V. safely on the ground

I would like to say that 9/10 landings land on the pad.. It feels more like 4/10 - the rest land within 10km of KSC. I wish we had better tools to gauge when we hit the atmosphere, and how much Kerbin had rotated when we get there. The most important space for the H.T.V. to judge how well the landing will stick is when I hit the "3rd band" of the atmosphere.. if my memory serves me well, around 35km - as it is there the speed is drastically reduced. 

I dont know.. If you could toggle the atmosphere bands to be shown on your maneuver node... that would be awesome. Or if the path projection actually accurately took the aerobraking into account.

The last bit of the mission required me to use the Methalox gliders of old. I decided to tweek the 1st stage by adding a "Spark" engine to help flip it - as it really speeds up the process on the H.T.V. 1st stage. 

I also decided to try do stage separation at 1800 Δv and ~1200 m/s rather than 1600Δv of old. It means that the 1st stage has around 350 Δv to land once it's gotten safe back through the atmosphere (burning at ~15% thrust with 3/7 engines to not lose the engine plate) The new design looks like this:

Methalox Glider coasting away from the 1st stage performing burn and flip maneuver.

This means that the Methalox glider has an extra 200 m/s for free - and saves methalox. that together with the revised docking method gives the glider a total of 300-400 more Δv for the re-entry burn. I had a lot of "trouble" that stemmed from the vehicle only having on average 300Δv to do the de-orbit burn. Only reducing the speed so much that it would bounce off the atmosphere and thus bleed of its speed slowly. This "sucked" as I also wanted to see a hot re-entry...

Unfortunately the vehicle still dont produce flames on re-entry.. I think the dev team can turn up the heat a bit - It's "too hard" to get vehicles to burn on re-entry x)

Any way with 300 more Δv it is now possible to break the glider enough to the atmosphere clean. How ever! this has revealed that the glider is off balance yet again. 

The first attempt I re-entered with a AoA at 40° - and it flipped to fly engine first. Then I tried an AoA 30° and then 10°... It kept flipping.. And I dont understand Why!

The VAB clearly shows that the Center of mass and Center of Drag is far apart.. and mass is infront of drag!:

The vehicle is in perfect balance when flying sub 1000m/s - It can even maintain a ÷20° prograde pointing ÷10° to the horizon and going 51 m/s at 4km altitude without stalling. SO... I have No idea why it's so unstable going through the hot re-entry.

Now.. Any sane person would just let it coast from 2000 m/s to 700 m/s by bouncing on the atmosphere.. and then glide easy down to KSC sub 1000 m/s avoiding flips - but not me.. So We are back at it again... Redeveloping the glider.

See detailed walkthrough in the spoiler section bellow:

Spoiler

We left off were the 1st stage was on its way back to KSC.

1st stage on its way back to KSC.

The 1st burning its engines to keep it from burning up on re-entry

There seems to be a bug in the game were as soon as you go from Orbit speed to Ground Speed it adds 100 m/s to your velocity. I lost 1 or 2 rockets to this error.. because I thought I was at the "allowed" 700-800 m/s. But as soon as I got into ground speed, it was 800+ and I did not have enough fuel to break it down to 700 m/s and land at the same time... so the choice was either it losing its engines or smashing into the ground. I solve this by making sure my velocity is set to ground from the start.

1st stage lining up the pad

unlike the H.T.V. and its 1st stage this can really glide - it can do ÷45° glide the last 10km off the ground.

1st stage landed.

The 300 Δv margin is a bit low - I may do stage separation at 1700 Δv instead of 1800Δv - just to have something for the last hovering part. 

The Methalox glider continuing the journey

Here you can see the 10km lower orbit to K.G.01 and the intercept point. Notice how little fuel difference there is between the two (since the  Δv counter is broken on this vehicle)

The Methalox Glider ready to break and match K.G.01s speed - passing by it only by a few meters. 

The Methalox Glider perfectly lining up the docking tower.

I really love the aesthetic of this little craft.. and it pains me that I have to go through its design again to stabilize it. Fearing it will turn ugly in the process.

Here seen from another angle

The Methalox Glider docked to K.G.01, and performing refueling.

The Methalox Glider lining up the runway.

After tumbling through the atmosphere - some how not burning up - I managed to line up the runway and glider there safely.

The Methalox Glider flaring before touch down.

Safe on the ground.

 

Moving Forward:

Only the refueling of Hydrogen on K.G.01 is left - and an investigation on why the glider has become unstable on re-entry again. I feel, with how every patch seem to drastically alter how winged vehicles perform, that tweeking and rebuilding the glider will be a continuing reoccurrence. 

Next post will be on the re-re-re-redevelopment of the glider and the refueling of Hydrogen.

Stay tuned for more - on this never ending story.

[BechMeister]

////////////////////MISSION_UPDATE\\\\\\\\\\\\\\\\\\\\

- Re-Re-Re-Designing Multi-fuel Glider -

The new and rebalanced Multi-Fuel Glider as well as its 5 prototype predecessors.

Foreword:

So, it took a little bit of fiddling around, crying and cursing before the glider was rebalanced. The new cheat tool is surprisingly helpful to quickly test re-entry etc. If you dont know how to "Summon" it, its Alt + F8.

Any way - After applying my brain and logic, I figured out how to fix the design. Since there are only one mission tasks in this update - Fixing the Multifuel glider - I decided to skip the Mission Task + lessons learned; lessons identified section and just go directly to the challenge.

The Challenge:

Image showing the center point of  the old glider.

So, what is the issue you may ask. I was dumbfound  by this strange conundrum. The center of Mass is clearly in front of the center of drag. So by all accounts there should not be any issues? The first few attempts at fixing the issue was centered around the idea of pushing the center of drag further back, by moving the front canards to the middle of the vehicle.

Not only did it not resolve the issue about flipping upon re-entry. it also made the vehicle fly like a rock. It struggled getting a pitch angle higher than ÷45° Which means a one in a life chance to flare up, bleed up all speed and slam into the runway pavement. 

Any way - It made me ponder a great deal. And I came to the conclusion. That the issue is not the center of drag. but the center of mass. The glider flips in the space between 30km and 40km, where the density of the atmosphere is between 0.001 and 0.006 kg/m³ - and the drag..

Looking at the glider as having no wings, the only logical explanation was that since the center of mass was beyond the center point of the craft. It would always fly with the most "massious" (is that a word..? it is now...) part in the front. Like how the capsule works. 

The problem I had to solve was this: Make sure the center of Mass is in front of the center of the vehicle. 

Easy right..? no.. not really.

Finding the solution:

There were two factors that made this a tough challenge:

1. While in vacuum - the center of mass had to be on or in front of center of the ship

2. While in atmosphere - The center of drag had to be closely behind the center of mass to make the vehicle steerable.

Solution to issue 1: with the new science update we finally got some decent "weights" you can add to the ship.

I added 3xGSCM -01 "Science JR"( 1t each) inside the nose cone. I swapped the MK2 Clamp-O-Tron out with the docking array I designed for the revamped escape shuttle (added another ~1t) . Lastly I added 2xsmall reaction wheels (under the clamp-o-tron) doubled the reaction wheel torque and pushed the Center of Mass in front of the center of the vehicle. 

This new nose solved  problem 1. But not Problem 2. It would re-enter perfect, but  was un-flyable once it got to the thicker parts of the atmosphere... due to the Center of mass and Center of Drag being too far a part. So the craft would nose dive into the ground. 

The wings are really heavy and I had to shift them forward as well. I managed to get center of mass in front of the center of the craft while keeping the center of drag close enough to the center of mass, how ever... The vehicle had become too heavy for the small wings. 

I was in a evil spiral - As the wings get bigger to give lift - they added mass - this added mass meant I had to add more mass to the nose to balance the craft - meaning I had to make the wings bigger. Not to mention that I had to be able to fly it into space on my 1st stage...

I reduced the 3x GSCM-01 to 2x. and the front assembly ended up looking like this:

note: MK2 clamp-o-tron for mass reference

This left me with a flyable craft. How ever I could not push the Center of Mass further front without the Center of Drag overtaking it. Something else had to be done.

Other Tweeks:

Spoiler

While struggling, I tweaked the rest of the craft - I got rid of the  two decouplers to separate the Methalox from the methalox pool (now the craft uses the cargo fuel, but I am good enough now that I dont accidently use it).

A lot of flight test was made keeping the Center of Mass on the Center of the Craft and keep the Center of Drag at the right ratio. I actually ended up balancing the craft so well I could remove the Canards and the final craft ended up consisting of these internals:

The wings are now Diamond shaped to get bigger control surfaces. (Big enough to steer the craft without the Canards - which i dont like the look off). I had to fiddle a bit with the rear landing gear to get the right placement, which in the end meant that they had to be increased in size to Medium, and moved away from the wings.

I really wish we had landing gear like the F16 or maybe rather the MIG-23 flogger, which as a girthy center mounted landing gear See spoiler (spoilerception):
 

Spoiler

 

 

All though the glider flew well now ("well enough" - being a lot heavier meant it flew more like the real shuttle than the glider it was before). It would not re-enter in a controlled fashion.

I was ready to give up on the craft... Until i noticed something, looking at real life examples for inspiration.

The Salvation:

I had to add more control surfaces to the ass that could press the nose down when it wanted to flip around. I looked at existing space planes and noticed that the X37b has it, The Space Shuttle had it.. The Venture Star would have had it (had US congress not killed the program) ESA Sky Rider and S.U.S.I.E. will have it... The body flap.

 

I decided to try add two Aerobreaks to the hind of the glider. set them deploy and then I tweaked the deployment rate from 0° to, what would be needed, while on the way down. When I could see that the SAS was fighting to keep the nose down, I increased the deployment rate of the breaks. Until the point were the SAS was stable. It turned out to be 25° as seen here:

Multi-fuel glider version 3 on re-entry.

I did not really like the look of the two Aerobreakes.. I wish you could change their shape like the wings. Or the game actually added a dedicated body flap. I tried to build a body flap using a wing like this:

An attempt at using a tiny wing as a body flap.

How ever. The problem is that when you add wings behind another wing, it changes what way it pitches up and down. I tried to reverse the middle wing... but the problem is that then Roll is fighting the SAS.. I tried to put the drone upside down, and then just fly with the ground up. But it did not fix the issue. So Aerobreakes it is.. As long as we dont have dedicated body flaps and or can separate pitch and roll on the invert option, Aero breaks it will be.

Conclusion and Certification:

From left to right: 1. Certified Multi-fuel glider v.III 2. Prototype III with wing body flap. 3. protype III with canards and without body flap. 4. prototype II with docking array from escape glider 5. Prototype I with weight in nose 6. Old Multi-Fuel glider v.II

Last thing on the list was to take the new Multi-fuel glider and complete a refuel mission at KSC. Since this post is already long enough I've added that part to the spoiler sections bellow:

Certification of Methalox Glider:

 

Spoiler

The Methalox glider enroute to LKO - notice the extra long connectors from the 1st stage to 2nd stage - The long aerobreakes meant that the 1st stage had to be extended for it to fit the glider.

The extra weight of the 2nd stage is not an issue, since the 1st stage had almost 200 Δv more than it needed for the old lighter glider. 

Long story short. I did not have to redesign the 1st stage to get the 2nd stage into orbit.

Stage separation.

1st stage has done its return burn and have KSC in sight.

Performing a break burn not to exceed 800 m/s

Slowing the decent to sub 5 m/s 

et voilà! Perfect landing back at KSC. 

With this very nimble stage I have gotten really good at returning to pad.

Back to the glider. Notice it flies with the "body flap" deployed - It is to make sure that the aerobreaks does not negate any thrust. 

I remember building the mun emergency lander, were I wanted to design it with the thrusters on top of the lander. Kind of like how Blue Origin has gone about it. But I found that the rockets lost a lot of thrust to the fuselage of the rocket - and It was impossible to balance the thrust to weight ratio - and get the right Δv readings and TWR readings in the VAB - So i Abandoned that idea.

Long story short - I did not want to test if the aerobreakes would have a negative effect on thrust.. so I deployed them. Flying upside down, they also help the vehicle to pitch nose up. So its not significantly altering the flight characteristics.

Here from another angle, were you can see the exhaust plumes does not get interfered by the "body flaps" 

performing the new improved rendezvous maneuver.

Break burn at K.G.01

getting into docking position. 

Lining up the docking docking port.

Approaching it at .2 m/s - Notice how the clamp-o-tron has been "pushed" into the docking tower. I wonder how long until I have to replace the docking tower. The ports seems to travel tiny bits at every docking maneuver.

Docked and transferring its load of Methalox and Monopropellant. I was contemplating reducing the monopropellant count on the vehicle, now that it got rebalanced. But the excess monopropellant allows me to refuel the monopropellant tanks as well. - maybe I won't need to make a MonoPropellant version.

Undocked from K.G.01 and ready to perform its deorbit burn. From this angle I actually think the Aerobreaks looks alright.

Re-entry - unfortunately the vehicle does not produce any reentry flames.. apparently it's too gentle on its re-entry. 

I think the dev teams can adjust the flames a bit.. it's actually "really hard" to get a vehicle to generate them I think x)

The new design has very good control and can re-enter at 40° AoA with the body flap deployed. I found out that if I dont deploy the flaps - I can re-enter at 90° and not flip. It's quite weird..

for a second it seemed like they were not necessary. I tried to remove them and the vehicle flipped.. by just being there, they make the craft stable... and if it's starting to flip around you can deploy them to their 25° position and regain control.

I do not understanding why it's like this... and it makes me think its something that will come back to bite me later. It could be a bug.

Side note: I added this marker drone to the front of the runway - it allows me to aim for the runway, so I can aim the prograde and go drink coffee while it glides the ~40km to KSC it usually has to travel - I find that if you timewarp the plane glides bad.

Here is an example of How I use it to aim the prograde at the run way. 

A cup of coffee later and I arrive here.

As you can see - the vehicle has to flare quite a lot under the extra weight. But it can "soft land" - as soft as a KSP vehicle lands on average.

The only weird thing is that the 2 rear landing gears tend to oscillate a lot - I think the springs may be too strong for the weight of the craft? I have tried to reduce spring strength to 0, while lining up the 6 versions for a screenshot, and it stoped. How ever I am not sure how it will land with no spring power. Future testing will tell.

And that was the Methalox glider certified and approved.

 

Certification of Hydrogen Glider: 

Spoiler

After that It was just certifying the Hydrogen Glider. - Its 1.5t lighter in fuel alone - So i was fairly sure it would make it. *spoiler* it made it with flying colors.

A session of stage separation and final travel through the atmosphere.

The 1st stage has a tendency to overtake the 2nd stage on stage separation. Something to be mindful off to avoid collisions when they start traveling each their way... and has to cross path again.

Glider waiting for the next maneuver, while keeping its solar panels pointing to the sun.

Arrival at K.G.01 - here the deployed body flaps are clearly visible.

Hydrogen Glider performing deorbit burn.

I was overshooting the KSC by a lot and had to do aggressive banking maneuvers to bleed off speed - still not a single flame was produced.

It meant that I had to approach the run way from the other side - were the old glider could fly at a ÷ 10° Pitch - this one does more of a ÷ 30° - meaning that its less forgiving of errors. How ever.. that is better than it burning up on the way down.

I thought it looked kind of cool with the blue reflection in the bodyflaps. making them practically invisible.

Final approach

Landed, Certified and Approved for operation.

 

Moving Forward:

Now that the gliders has been fixed again, again, again.. I can go back to refueling K.G.01 with Hydrogen.

We will see if any more setbacks present themselves before the end is here.

Stay Tuned for more!

 

Edited January 28 by BechMeister
Fixed poorly written section