JEM : Jool 5 - The Hard Way - Mission Complete!

[Starhawk]

Click on the image below to take a look at JEM - the core craft of the Jool Exploration Mission.

What we have is an empty and locked off size 3 tank surrounded by 12 Nervas. Above that is a size 2 probe core with a standard docking port on top of that.

Attached to the node of the docking port is the central engine of the lander, which is strutted to the size 3 tank. At the bottom of the size 3 tank is a Clamp-o-tron Sr.

The concept of this mission is to try out orbital construction and attempt to design a modular system which would allow for orbital construction of various sizes of craft from a few standard pieces, most of which can be carried to orbit inside the cargo bays of spaceplanes. One of the mission parameters is to have as few vertical launches as possible, at least for the initial craft.

The modules in question are orange tanks with a Clamp-o-tron Sr. at either end and a few other bits in between. The core JEM craft consisting of the lander and the IP tug will have as many modules attached as we can handle and, along with the Laythe lander, form the main ship of the mission. The Nervas will draw from the farthest tank first and each module can be detached when empty saving some mass.

This ship is the first launch and the only vertical launch used in initial JEM craft.

The staging is somewhat unusual. When the lower stage is empty, the fairing is jettisoned, and then the docking port node holding the Sr. to the lifter is decoupled. The partially fuelled lander tanks provide fuel for the Nervas which act as the upper stage. After achieving orbit, the JEM will rendezvous with Kerbin Station and fuel up the lander completely.

Here's a shot of JEM coming in to dock at Kerbin Station.

And here's one of JEM docked. Adjacent to JEM are an escape pod module still strutted to the tug which delivered it. This tug will be used to assemble the JEM ship. Also docked at the station is a Minmus tanker.

Much, much more to come...

Happy landings!

Edited November 5, 2015 by Starhawk
Nobody clicking album- added images in spoiler.

[SpaceplaneAddict]

Good luck! My Jool-5 ran into a snag with ladders, make sure to check em!

[Starhawk]

Significant ladder testing was done on the pad. I once had a ladder problem at Eve.

Happy landings!

[Starhawk]

The next step was the crucial one of designing a spaceplane capable of carrying a full orange tank to orbit.

Some of you may have noticed that aesthetic considerations are not the top priority of my engineering team. This observation is borne out when looking at the resulting craft.

Design and testing were pursued feverishly under the pressure of already having the kerbonauts in their craft in orbit and waiting for the rest of the ship. The engineering staff's creativity also extends to the naming schemes for most of the craft. We finally created something that looks like it will do the job - the 'Cargo Mk3'.

And here she is just after releasing her cargo. As ugly as promised. The astute reader may notice a fundamental flaw in the spaceplane at this point. I was much too busy thinking about the various docking maneuvers coming up. The spaceplane barely made orbit, and so left the module in a very low orbit.

There was just enough fuel to deorbit and everything was going well at this point. Reentry was nominal until I was close to KSC and below shock-heating speed and altitude. I tried to steer to line up the runway, and the obvious and debilitating lack of a vertical stabilizer became immediately apparent. I saved the crew, but the craft was pretty much completely disassembled. It was a prototype, anyway.

The engineering staff statement to the review board: "We were told to change out the tailplane. We detached the old one and took it into the back. When we came back into the hangar with the new one, the ship was already rolling down the runway."

Knowing that the crew was safe, I proceeded to send my tug from Kerbin station down to lower orbit to grab the newly delivered module and return it to the station where JEM was docked and waiting. JEM undocked and the tug brought the module in for the docking of the very first module added to JEM. The first module is an orange tank, size 2 reaction wheel, and a size 2 battery. This module contains LFO that will be used for refueling the lander.

The tug worked beautifully, despite the mass of the somewhat unwieldy module. I comforted myself with the thought that the others would be much lighter.

The remaining modules will provide liquid fuel for the Nervas, and support equipment. The second module will have solar panels and radiators placed at one end to avoid exhaust impingement. The spaceplane was redesigned now that it only needed to carry half the cargo to orbit.

Here's a long sequence of images from the delivery and attachment process.

At this point I decided the modules were still too unwieldy and all the rest should be equipped with RCS thruster blocks for ease of maneuvering, and for assistance with turning such a long and massive ship as the JEM would eventually be.

Much, much more to come.

Happy landings!

Edited October 29, 2015 by Starhawk

[Mister Dilsby]

Excellent report, and what a ship that is! The explanation of the tailplane deletion made perfect Kerbal sense to me. And I have always wanted to say this--"You must spread some Reputation around before giving it to Starhawk again."

[Starhawk]

Excellent report, and what a ship that is! The explanation of the tailplane deletion made perfect Kerbal sense to me. And I have always wanted to say this--"You must spread some Reputation around before giving it to Starhawk again."

Thank you kindly, Kuzzter. That's mighty nice of you.

Some details about the mission plan. There will be no ISRU on this mission, in case that wasn't obvious from the 'Hard Way' part of the name. All three kerbonauts will set foot on every moon. This is mostly just a flags, footprints, and photos mission. The only science gear we'll bring is Bob. He can generate Crew Reports, EVA Reports, and grab Surface Samples. More than enough to satisfy Linus, Wernher, and the contracts.

The main lander will be used to land on Tylo, and staged during ascent from the surface. The core stage will be the lander for Vall, Bop, and Pol, as well as the return and reentry craft. The Laythe lander has yet to make an appearance.

There will be a refueling/resupply mission as well. The exact specs of that mission have yet to be determined at this point.

Anyway, the construction continued apace with the 'Cargo Mk3' spaceplane series design being refined with each iteration. There was one more tiny mishap upon landing (I dislike night landings!) before the design was refined sufficiently. Mort was... somewhat displeased. This time I got a pic of the aftermath of the 'Good Landing' .

The spaceplane series was refined further and soon named 'Unicorn' for reasons that become obvious in the pics below. The name 'Narwhaal' was briefly considered. I think the aesthetics of the cargo planes improved significantly over time. Others may disagree.

Here is a huge Imgur album containing many pics of the orbital construction process.

And here is a series of shots giving a summary of the process.

Now, JEM begins to take her final shape. A sort of 'Wagon Train to the Moons', if you will.

After flying each of the seven missions which delivered a module and returning more or less safely to Kerbin, Jeb and his faithful crew of whitesuits have completed their portion of the mission. It's been decided that any further missions to deliver modules can be done by Wernher's newly designed remote control cargo spaceplane, saving funds. And, hopefully, reducing the prevalance of Mort moping around the KSC facilities, and checking the coin returns of the snack machines for loose change.

The next update will introduce the Laythe lander and complete the construction process.

Happy landings!

- Trademark owned by Kerbfleet.

Edited October 24, 2015 by Starhawk

[Starhawk]

Here's a teaser shot of the Layther lander during testing on Kerbin.

Happy landings!

[SpaceplaneAddict]

Than main ship looks ludicrously big. My laptop cried when it thought of that AND all the landers.

-SPAddict.

PS: Good luck!

[Starhawk]

Felix Kerman was assigned the task of test piloting the Laythe lander since Jeb was busy flying the missions bringing the modules up to JEM. The craft was named the Tri-Flyer for the three kerbals it would carry down to the Laythe's surface and return to LLO.

After the design checked out, Felix was assigned to fly the Tri-Flyer up to Kerbin Station where it docked and was refueled for the mission.

The tanks and battery of the Try-Flyer were locked off and Felix transferred to the station. Meanwhile the tug rendezvoused with the station and awaited the release of the Tri-Flyer from the station. The Tri-Flyer was released as dead weight and grabbed by the tug. The tug proceeded to rendezvous with JEM once again.

I then proceeded to pull off the coolest docking I've ever done. I carefully lined up on the axis of JEM carrying the Tri-Flyer as dead weight. The dockings had grown a bit routine for me, and I wasn't even using Docking Port Alignment Indicator most of the time, but it was invaluable for this. I changed attitude so that the tug was directly between JEM and the Tri-Flyer. I began to gently thrust back toward JEM, pulling the Tri-Flyer along. I minutely adjusted the alignment and then proceeded to undock the Tri-Flyer. I added a bit of additional thrust toward the JEM and then quickly off to the side to get out of the way. I switched the focus to JEM and watched as the Tri-Flyer glided in to dock with JEM.

I got it on the second try.

A conference was called with the engineering staff and the consensus was 'More Fuel', so another mission was scheduled to deliver a final module to JEM. This time the new cargo drone was used for the delivery.

Here she is - complete. I pushed it as far as I thought I could go. TWR was 0.24, and dv with all lander tanks full and locked off was 3131 m/s. The huge uncertainty in the cost to capture and the viability of aerobraking at Laythe have left Bob and I with 'concerns' .

At this point I got a bit distracted with learning how to get Hummlebee to orbit atop the Orange Knight while the crew waited for the transfer window.

Next time - we burn for Jool!

Happy landings!

- - - Updated - - -

Than main ship looks ludicrously big. My laptop cried when it thought of that AND all the landers.

She's 306 tonnes and 199 parts. There are really only the two landers. The main lander and the Tri-Flyer.

Happy landings!

Trademark owned by Kerbfleet.

Edited October 25, 2015 by Starhawk
sp

[Thegamer211]

Happy larndings!

Larndings?

Does JEM stand for Jool Excursion Module?

Nice ships, and woah that transfer stage.

[Starhawk]

Larndings?

The downside of posting under the influence of 'hydrazine'. I'll correct that straightaway.

Does JEM stand for Jool Excursion Module?

It stands for Jool Exploration Mission.

Nice ships, and woah that transfer stage.

Thanks. The proof is in the pudding. I'll post the next update later today.

Happy landings!

[SpaceplaneAddict]

Can't wait to see the next update! P.S: Is your Laythe lander a spaceplane? 'Cause I did one too!

- - - Updated - - -

Felix Kerman was assigned the task of test piloting the Laythe lander since Jeb was busy flying the missions bringing the modules up to JEM. The craft was named the Tri-Flyer for the three kerbals it would carry down to the Laythe's surface and return to LLO.

http://i.imgur.com/scT3VZm.png

After the design checked out, Felix was assigned to fly the Tri-Flyer up to Kerbin Station where it docked and was refueled for the mission.

http://i.imgur.com/2ey9fOz.png

The tanks and battery of the Try-Flyer were locked off and Felix transferred to the station. Meanwhile the tug rendezvoused with the station and awaited the release of the Tri-Flyer from the station. The Tri-Flyer was released as dead weight and grabbed by the tug. The tug proceeded to rendezvous with JEM once again.

http://i.imgur.com/Q85hEEc.png

I then proceeded to pull off the coolest docking I've ever done. I carefully lined up on the axis of JEM carrying the Tri-Flyer as dead weight. The dockings had grown a bit routine for me, and I wasn't even using Docking Port Alignment Indicator most of the time, but it was invaluable for this. I changed attitude so that the tug was directly between JEM and the Tri-Flyer. I began to gently thrust back toward JEM, pulling the Tri-Flyer along. I minutely adjusted the alignment and then proceeded to undock the Tri-Flyer. I added a bit of additional thrust toward the JEM and then quickly off to the side to get out of the way. I switched the focus to JEM and watched as the Tri-Flyer glided in to dock with JEM.

I got it on the second try.

http://i.imgur.com/YuVncoI.pnghttp://i.imgur.com/QxB7cv1.png

A conference was called with the engineering staff and the consensus was 'More Fuel', so another mission was scheduled to deliver a final module to JEM. This time the new cargo drone was used for the delivery.

http://i.imgur.com/1FXcD1S.pnghttp://i.imgur.com/xp2Y30F.pnghttp://i.imgur.com/uA8S3Vw.png

Here she is - complete. I pushed it as far as I thought I could go. TWR was 0.24, and dv with all lander tanks full and locked off was 3131 m/s. The huge uncertainty in the cost to capture and the viability of aerobraking at Laythe have left Bob and I with 'concerns' .

http://i.imgur.com/XTqvEjp.png

At this point I got a bit distracted with learning how to get Hummlebee to orbit atop the Orange Knight while the crew waited for the transfer window.

Next time - we burn for Jool!

Happy landings!

- - - Updated - - -

She's 306 tonnes and 199 parts. There are really only the two landers. The main lander and the Tri-Flyer.

Happy landings!

Trademark owned by Kerbfleet.

How about trying a Reverse Tylo GravSlin^TM*?

*​Trademark owned by AddictionAeroworks

[Starhawk]

SpaceplaneAddict said:

Can't wait to see the next update! P.S: Is your Laythe lander a spaceplane? 'Cause I did one too!

I should hope yours is a spaceplane, given your username and stated predilection. Actually, I've seen it, and it's very nice.

Quote

How about trying a Reverse Tylo GravSlin^TM*?

*​Trademark owned by AddictionAeroworks

Tylo gravity capture FTW.

There won't be a huge amount of delta-v left after the burn for Jool, even with dropping empty tanks as we burn. This is among the biggest concerns that Bob and I have.

Others include:

-The RCS thrusters were neglected on module 8

-Module 3 has the thruster blocks rotated 90 into the body of the tank (the engineers down at KSC said "We think they may still work like that. Why not give it a try?")

-The RCS thruster blocks that are there aren't all aligned nicely

-There's no telling how wobbly this thing will be under acceleration, but in the simulations it turns okay... Sorta.. for a really big, heavy, floppy craft.

So yeah. On to the burn shortly.

I forgot to mention in the OP, the mods used for the mission are as follows:

• EVE
• Chatterer
• KER
• KAC
• Enhanced NavBall
• Precise Node
• RCS Build Aid
• Editor Extensions
• Intake Build Aid
• DPAI
• Asteroid Day
• Stock Bug Fix Modules

Happy landings!

Edited November 30, 2015 by Starhawk

[SpaceplaneAddict]

A little late for a ship suggestion, but with Stock Fuel Switch, you could've gotten a LOT more LF per tank

[Thegamer211]

The downside of posting under the influence of 'hydrazine'. I'll correct that straightaway.

I feel like hydrazine will become an inside joke of the forum.

[Starhawk]

I feel like hydrazine will become an inside joke of the forum.

I should have said "Under the influence of 'hydrazine'."

Happy landings!

tm- Trademark wholly owned by Kerbfleet.

[Starhawk]

With the transfer window about a day away it was time to plan the burn.

With this low TWR we had to split the burn. It was decided that two burns would work well.

Transfer Planner said we'd need about 1900 m/s for our burn to Jool. The maneuver node was set up for the whole 1900 and the ejection angle checked. Then the maneuver node was reduced to about 800 m/s giving us an apo of 8000 km. Well inside the Mun's orbit and with a period of about 1 day and 3 hours. I set up another maneuver node and slid it exactly over the original one, but set it for one orbit later. That node was given the remaining 1100 m/s. This allows the burn to be split without having to worry too much about figuring out the timing for the first burn.

Ready to start the burn.

We carefully monitored the fuel level and undocked each orange tank as it emptied.

The SAS 'Hold Maneuver' function was having a very hard time staying on course.

The first tank was undocked and dropped away. This is NOT a tidy space program.

Running a bit warm after the first burn, and that was the shorter one!

So with the first burn complete, here's how things looked.

We rode around the orbit for 1 day and 3 hours allowing plenty of time for the radiators to cool everything back down.

Time for the second burn. This time I got the maneuver lined up and then set SAS to 'Stability Assist'. That worked much better - there were definitely fewer steering losses this time.

I had some fears about the heat from the Nervas on the burn, but they proved to be unfounded - the two radiators managed the heat and nothing exploded.

Finally, here's JEM headed for Jool. She was now four orange tanks shorter and, hopefully, a bit more maneuverable from here on out.

Happy landings!

- - - Updated - - -

A little late for a ship suggestion, but with Stock Fuel Switch, you could've gotten a LOT more LF per tank

Yeah, she's definitely not the peak of efficiency. Our veteran crew are confident that they can manage her anyway.

[Mister Dilsby]

Very nice sequence of the ejection burn et al; I really like the concept of the forward mounted LV-N ring and the long long train of orange tanks. You could get anything to anywhere with that setup! One thing I'd really like to see is the collection of orbital arcs all those empty tanks are making:).

Laythe ship design is also pretty sweet. I might have looked for a more "battlestar" way to carry it, but of course there's no real need for that kind of foolishness. Impressed you were able to balance torque well enough with it mounted crosswise like that.

Finally I support your stockliness very much--yes it's stupid there's no good LF tank option for a rocket this size, but I personally find working within the constraints of stock parts to be very rewarding.

On to Jool! And BTW Admiral Shirley called, she says you can use any Kerbfleet references you see fit to include, or no

[Starhawk]

Very nice sequence of the ejection burn et al; I really like the concept of the forward mounted LV-N ring and the long long train of orange tanks. You could get anything to anywhere with that setup! One thing I'd really like to see is the collection of orbital arcs all those empty tanks are making:).

And so you shall.

Laythe ship design is also pretty sweet. I might have looked for a more "battlestar" way to carry it, but of course there's no real need for that kind of foolishness. Impressed you were able to balance torque well enough with it mounted crosswise like that.

Thanks. I spent considerable time balancing the craft, and I knew that the docking port was set right under CoM. Nonetheless, I was quite surprised when my docking trick worked as well as it did.

Finally I support your stockliness very much--yes it's stupid there's no good LF tank option for a rocket this size, but I personally find working within the constraints of stock parts to be very rewarding.

I appreciate that a lot. It definitely is rewarding when you can meet the design challenges you set for yourself.

On to Jool! And BTW Admiral Shirley called, she says you can use any Kerbfleet references you see fit to include, or no

Please thank the Admiral for me the next time you speak to her.

Didn't have time to get the capture pics up tonight. Tomorrow we'll get a look at JEM in the Jool system.

Happy landings!

[Starhawk]

There was a plane change to do out near Dres orbit, and I tweaked it a bit to get a Tylo encounter. Not quite what I want, but at least the trajectory doesn't go through Tylo's surface.

I spent some time trying to improve it, but it didn't want to be accurate that far out. I figured Val, Bob, and Bill would be able to tweak the trajectory once we were close.

In the meantime...

This is the first career where I've ever run concurrent missions. It makes it interesting. At this point I had a Gilly Rescue SOI change coming up, an Ike Rescue ship to launch, an asteroid to grab, and a course correction for my Eeloo probe coming up. So I got busy and finished all of those and could look to my arrival at the Jool system.

We'll finally see the gravity capture in the next mission update which will be a bit later today.

Happy landings!

[Starhawk]

Gravity assists are hard.

Yes, they are. But I stand by what I said before:

Tylo Laythe Gravity Capture FTW!

Well, we found ourselves safely across the SOI boundary and entering a strange and wondrous place far, far from home.

Val, Bob, Bill, and I spent an inordinate amount of time working on refining the Tylo gravity assist. Innumerable courses were plotted. Many were even 'simulated'. None I could find would provide the appropriate trajectory. The required burn at the very high apoapsis after the Tylo encounter was too high. All the best post-encounter trajectories required the ship to travel directly through the surface of Tylo. D:

Finally one of us decided to start thinking outside the narrow parameters which were being considered. It may have been Bob's idea, I can't remember. But, finally, a trajectory for a Laythe gravity capture was attempted. And, lo and behold, there it was.

It would only take a tiny radial adjustment to set it up and a burn of about 275 m/s at apo to get the peri out of Jool's surface and atmo. Because we were so far out toward the edge of the SOI, every tiny movement of the craft affected the trajectory enormously. With the floppiness of the craft, it was quite difficult to get it pointed at the ever-jittering maneuver node.

Since we had tonnes of mono aboard, it was decided that this would be used for the course change. The use of RCS thrust-balancing (AKA Fine Control Mode) was necessary, but we were able to adjust course in multiple dimensions in small increments without having to turn the craft. Used up most of a full size 2 mono tank!

Once we made the burns we had our apo outside Tylo's orbit and our peri outside Jool's surface. A bit of experimenting at this point yielded one of Jool's beautiful trajectory solutions.

A little more adjustment and we had something that the crew were starting to get excited about.

When we focused on Laythe and saw this I shouted with joy.

KSC, the crew, and I all knew this was a capture we could do!

All right, a couple of operational notes. With the exact shape of the resupply mission still undecided the choice was made to keep all four orange tank modules attached, even though one was empty. The planners felt that it was best to keep as many options open as possible at this point.

The mission plan calls for low orbit at Laythe (hopefully we can find a safe aerobraking solution) once Laythe capture has been achieved. The Tri-Flyer will take the crew to the surface and back and rendezvous with the JEM mother ship. After docking and crew transfer the Tri-Flyer will be detached and left in LLO for the use of future crews. This lightens the JEM mother ship's load a bit. Just a bit though - that lander with the Tylo descent stage on is a heavy beast.

All right - finally, here's the Laythe insertion.

And here's a shot of the maneuver set up to burn for aerobraking. The burn is 117 m/s and we still have over 700 with the Tri-Flyer attached.

Next time - will she burn up?

Happy landings! (maybe... eventually...)

Edited October 27, 2015 by Starhawk

[Mister Dilsby]

Wow, great shots and a VERY nice intercept. If you don't mind me saying so, I think you're a strutty-eyed booster kerb!

Since we had tonnes of mono aboard, it was decided that this would be used for the course change. The use of RCS thrust-balancing (AKA Fine Control Mode) was necessary, but we were able to adjust course in multiple dimensions in small increments without having to turn the craft. Used up most of a full size 2 mono tank!

Yeah, this is how I do it, unless I'm bingo on mono. I'm not above giving it a few puffs in every direction just to see how it affects the periapsis. And that way even if I don't have enough mono to get it where I want, I can always turn in that direction and fire the main engine ONE time instead of hacking and starting over again and again.

Jool system is somewhere I've never been, though i have Big Plans for a mission in 1.1. (or maybe 1.0.5) Really looking forward to seeing your plane over Laythe!

[Starhawk]

WOOOO! The head of Kerbfleet called me 'a strutty-eyed booster kerb!'

I'm so honoured. That means much more than any light-green bar!

Thanks Kuzzter.

Happy landings!

Edited October 28, 2015 by Starhawk
sp

[Starhawk]

Having successfully cleared the first two major hurdles we faced (capture at Jool and capture at Laythe) we were on to the next one.

Aerobraking. Given that KER was underreporting the mother ship's delta-v by about 30% it was considered vital to save delta-v and aerobrake into our parking orbit. A couple of 'simulations' were run and in we went.

The heat wasn't too bad at this velocity and, despite the small wings, the aerobraking was effective. If somewhat slow. Time, we had.

We made several passes and slowly made progress.

Then we took a moment to be all touristy.

And then, back into the fire.

Our orbit was deemed low enough. The crew transferred to the Tri-Flyer, powered it all up, and undocked.

Despite a couple of nagging 'concerns', atmospheric entry was nominal. Not to mention quite beautiful.

The Tri-Flyer performed even better than we'd hoped. She glided right in to a beautiful landing next to the shore under Val's cool hand. Bob was moaning "It looks like you're going to hit the ocean!" the entire time. As always, his demeanor improved as soon as we rolled to a stop.

After a brief moment of leg-stretching, flag-planting, and surface-sampling, it was time to get back into the ship. I was really hoping for one of those wonderful views of Jool during the ascent, but it was not to be.

In this crucial phase the Tri-Flyer also performed beautifully. This was part of the mission in which we had complete confidence. We knew the capabilities of the spaceplane and believed that Laythe ascent would be very forgiving. We had enough fuel on board to make a Kerbin ascent (just barely) so we knew it would be overkill for Laythe. But by how much? We would see after the rendezvous.

Turns out there was loads left.

Next time - examining our options.

Happy landings!

[lajoswinkler]

Pinballing around Jool is so much fun if you're careful.