Dave's Voyage (.23 career log, PIC HEAVY, ANI GIFs)

[Dave Kerbin]

I have a previous .22 career documented here and this will be my .23 career.

This career will be done a little differently. I will be playing with some new restrictions and removing some old ones. To nail down some of the difficulty this new save file will have several of the hidden options enabled: Kerbals won't respawn, the revert menu will be disabled, quick save won't work and it won't be possible to delete ships in flight or access the stock craft files. At the same time I'll be relaxing a few rules: With the .23 improvements I won't have any special rules for transmissions. I will also allow nuclear engines with Kerbals since it caused a lot of extra busy work, this time I will be using a mission structure to make it challenging by having interplanetary missions before nuclear engines are even available. I will also be dropping the rules about habitat. As long as there is a pod and not just a chair it is ok. Kerbals must return home, no one gets left behind. I'll also be removing Jeb, Bill and Bob from the save file before starting, it will be all kerbals you haven't met before.

Because I'll be playing with all the save/revert options removed it means I will be at the mercy of glitches and bugs. These will be treated as 'equipment failures' to be worked around, Apollo 13 style.

While last time I tried to challenge myself with special rules for interplanetary travel this time I want to try to challenge myself by forcing myself to get out there sooner instead of sending half a dozen missions to the Mun. So the kongressional kommittee in charge of the space program's budget has forwarded a list of specific projects it wants to see completed. While some testing of equipment is allowed the kommittee will not support the funding of missions that don't pursue the stated goals. Once a project's goals are completed the kommittee will expect the KSC to move on to the next project. Ships will be named after their project and numbered - for example the first launch would be Reach I and if that failed to complete Project Reach's goals then Reach II would be launched and so on. In some cases a project may need to be put on hold until the required technology is developed. In that case it can be skipped until the required parts become available.

Here is the project list. I'll be adding links for each mission report as it is flown.

Phase 1 - Looking Up

Project Reach

Escape the atmosphere (fly above 70km)

Reach 1 62 Science

Project Leap

Orbit the planet more then once.

Leap 1 115 Science

Project Gander

Take a look at the dark side of the Mun.

Gander 1 594 Science

Phase 2 - Small Steps

Project Cheese

Plant a flag in one of the Mun’s craters

Cheese 1 947 Science

Project Mint

Obtain a sample of that yummy looking green stuff on Minmus…for testing.

Mint 1 2378 Science

Project Berry

Send a probe below the thick clouds of Eve and report what is there.

Berry 1 665 Science

Phase 3 - Great Journeys

Project Martian

Search for life on Duna.

Martian 1 4495 Science

Project Icarus

Measure the temperature on the surface of Moho during the day.

Icarus 1 160 Science

Icarus 2 210 Science

Project Tyson

Send a kerbal to determine if Dres is a planet or not.

Tyson 1 1446 Science

Phase 4 - Inquisitive Minds

Project Ice

Determine if earthquakes caused the cracks seen on Eeloo by taking seismic readings.

Ice 1 555 Science

Project Dust

Study the formation of the solar system by collecting rock samples from captured asteroids – Gilly, Bop and Pol.

Dust 1 1889 Science

Dust 2 4154 Science

Project Stone

Measure the gravity around all of Jool’s moons.

Stone 1 560 Science

Phase 5 - The Future

Project Sunshine

View the sunrise with a friend on Moho.

Project Garden

Determine the habitability of Laythe. Take barometer, temperature and atmospheric readings and collect some liquid from the ocean. Setup a laboratory within Laythe's sphere of influence to study the environment's effect on biological samples brought from Kerbin.

Project Bloom

Visit Kerbin's sister planet. Return a sample of dirt and liquid from Eve.

Questions Or Comments Are Welcome!

Edited January 27, 2014 by Dave Kerbin

[Dave Kerbin]

Reach 1

Our goal is escape Kerbin's atmosphere with the limited technology at our disposal. Based on the work of Ksiolkovsky Kerman 3 fuel tanks would just enough to pass into space, but we want some margin of safety and an opportunity to look around so we will use 4. More then 4 brings into questions whether our parachute system will be enough.

The rocket is assembled and our first pilot Rayfrod Kerman is loaded in and wheeled out to the launchpad. He opens up the hatch to make an inspection of his rocket before takeoff - he is not really sure this will work but he will try. Rayfrod contacts mission control and tells them he is ready to go.

After the engine is lit Rayfrod slowly eases up the throttle, lifting off at about 25% and holding steady at 30%. At 20km he reports the the flight is stable and he is gaining speed and altitude, now traveling 560m/s. At 36km the engine stops with velocity at 1175m/s.

Rayfrod steps outside to see if he can determine what has caused the engine to stop. After determining the fuel tanks are empty he gets back into the cabin and performs some navigational checks. In a few moments he is in space and quickly reports these findings to mission control. Mission control says he should run out of momentum at around 125km. With some time to spare Rayfrod decides to spend some time checking it out.

After boarding the ship eventually starts to fall back to Kerbin. Rayfrod observes something burning outside the window, followed by a loud whipping sound before he opened his parachutes.

Just before landing there is a loud bang followed by some cabin movement and another bang. Rayfrod gets out to investigate and finds the engine and one fuel tank missing. Maybe the engineers should look into that. He takes a souvenir and declares the mission over.

Including the data from the reports sent to mission control Reach 1 has produced 62 science. All but 4 of that is invested into new technology for the next mission.

• Project Reach completed.
  
• Flew into space.
  
• Collected 62 science.
  
• Unlocked Basic Rocketry, General Rocketry, Stability and Survivability.
  
• 4 science saved.
  

[Dave Kerbin]

Leap 1

Our mission is to orbit Kerbin. We have new tools including decouplers and better engines, we also have our first experiment the goo canister.

With staging the rocket can be bigger and I've stacked goo containers all around just to be sure I have enough. One thing that is new with this career is that with revert disabled entirely I can't just put a rocket on the pad to check weight or spacing or anything like that. I had to be really careful and hope that I wasn't blocking the hatch and that I'd gotten all my calculations right, because when I put the rocket on the pad that's the launch for real. Leap 1 is also going to use some tweakables - I've calculated my burn rates so that I can put the throttle at 100% the whole way and not worry about terminal velocity or TWR. I did mess up with my center engine, setting it to 94% when my calculations said 95% but this results in less then 3 seconds where my acceleration stalled before fuel use leveled things out. I also removed the monopropellent from the command pod. Without RCS thrusters available yet it doesn't make sense to carry the extra weight.

Leap 1 is a basic 3 stage design. It burns 4 outer engines first, then those drop away and the center engine takes over before finally it is dropped and the smaller orbital engine completes the burn. After the deorbit burn the command pod detaches from the rest of the rocket for reentry.

On the launch pad things appear stable, I've tried to keep the rocket as short as possible to reduce the risk of tip over and ensure it is balanced on the 4 rocket nozzles. Rayfrod is our pilot again and he takes a reference reading for the goo so we have something to compare the other samples to.

The moment of truth comes and we activate the engines. The calculations appear to be correct and we smoothly lift off the pad. As the rocket ascends more goo data is collected and at around 12km we begin a gravity turn and eject the first stage, lighting up the next. We are aiming for a heavily inclined orbit so that we can cover a large amount of Kerbin's surface area. Goo containers continue to be exposed as we ascend.

With a strong suborbital trajectory the depleted second stage is released and the orbital vehicle begins to coast toward AP. Along the way more goo observations are made. For our AP burn we are going to alter our course a little more, in order to bring the ice caps under our orbital path.

From here it seems we've exhausted the applications for our goo modules, perhaps we brought too many. Rayfrod looks up at the tiny window in his pod and decides that it is too small, if he is going to travel over Kerbin he wants a view.

After 2 orbits Rayfrod collects the samples from the goo containers and returns them to the command pod.

A plan to return is made and the orbital section burns for reentry and then detaches. The pod returns for a safe landing.

With the data from crew reports Leap 1 has returned 115 science. Most of the science came from EVA reports observing the various biomes of Kerbin from space. Science Tech is unlocked giving us the Science Jr materials bay and batteries. The rest is being saved to pursue Electrics later.

• Project Leap completed.
  
• Orbited Kerbin twice
  
• Collected 115 science.
  
• Unlocked Science Tech.
  
• 74 science saved.
  

[Dave Kerbin]

As a side note the first time played through career in .22 I did so without any spoilers - I was discovering the tech tree as I went along so when it came to parts I could only see one step ahead. For .23 the tech tree is (as far as I know) the same with the exception of the new lab being added. With knowledge of the tech tree my scientists have been working with a roadmap this time. Items marked in red are consider high importance, orange are medium and white is low. The green is what I've already unlocked.

My most immediate goals solar panels and fuel ducts which will let me engineer much more efficient spaceships instead of using a lot of redundent components. After I'll be focusing on more advanced science instruments, but I'll need the Stayputnick for Project Berry (that's not for a while so I'm not worried) and I'd probably like to have the Mk1 Lander Can and docking ports by the time I get to Project Martian.

[Dave Kerbin]

Gander 1

Orbiting the Mun is our next objective, a mission profile very similar to the one flown by Apollo 8 almost 45 years ago to the day. We also have one new instrument to test, the materials labs (Science Jr) and we have batteries now. Part of the planning that goes into these missions is determining what experiments will be run during the mission. In Leap the goo experiment was a bit of a stab in the dark and I ended up with a lot more canisters then I needed. On this mission my failed estimate was crew reports, I thought I might be able to file crew reports about various possible landing sites on the Mun. Without solar panels that meant I would need a power reserve to send them all. I initially determined that 4 batteries would be enough, and then because they where so light I doubled that to 8. The actual number of crew reports from the Mun was 2 - one from high orbit and one from low orbit.

The size of the lifter is getting bigger, I'll want to start using fuel lines soon to keep it under control. Bigger fuel tanks like the T800 would also help since right now I've got engines dangling off a stack of 4x T400s attached by a single radial decoupler. The staging is a bit strange for this one starting with the first 'stage' which consists of a materials bay which is exposed on the launchpad as our control sample. Since there is no point in bringing it into space it is dropped onto the launchpad for later recovery before we even ignite the engines. I used landing gear to cushion the short fall.

The second stage consists mainly of the four T45 engines, but since I was a bit concerned about overall delta-v and some too-close to call TWR figures I added a small center LV909 engine with a single T400 tank to provide extra thrust. I calculated the fuel consumption based on thrust and set it so that the center engine would run out with a little time to spare before the outer 4 engines where exhausted. The reason for this was that the center engine wouldn't be able to support the mass of the ship at all, and without being able to predict the exact fuel consumption ascending through the atmosphere I didn't want to try matching their burn times exactly. My launch checklist indicates that if the center engine cuts out before the gravity turn I can drop it immediately. Since I had to start my gravity turn before it ran out I kept it on. The radial stacks did sway a bit but the thrust vectoring kept everything flying straight.

Ultimately the center engine had a tiny bit of fuel left so I just cut the throttle and ejected it with the stage key, then throttled up and ejected the radial keys by tapping the stage key again. This resulted in an explosion as the exhaust plume seemed to ignite the discarded center fuel tank and the debris ripped apart most of the radial tanks. I thought something would be damaged on the main rocket but a full check showed the upper stage had cleared the explosion and an abort wasn't required. The center engine has two T400 tanks to burn before it gives way to the orbital stage.

As we've been ascending I've also been taking observations with the material bays. The lower part of the main spacecraft contains 3 material bays which have been used to observe the upper and lower atmosphere and low orbit conditions. We've got a tiny amount of fuel in the booster stage so we'll be burning that before the main orbit stage comes online to complete our orbit. In orbit an EVA is performed to collect the data from all 3 bays, since the orbit stage they are attached to will be discarded shortly.

The orbit stage still has about 30% fuel left - this was planned since we didn't want to run out of fuel and eject that stage before reaching stable orbit (losing our material bays before we could collect the results). The injection burn to the Mun is planned out and the orbit stage is burned off before being discarded for the final Mun engine.

However that stage won't be the last thing we discard. As we reach high orbit around Kerbin on the way to the Mun we use one of the radially attached material bays and the other one is used once we've entered the Mun's SOI in high orbit. An EVA collects the results and then both of these bays are discarded to reduce weight before our capture burn. In hindsight I should have also attached the two lower goo containers to the material bays as well, since they are used in the same manner.

We capture into a deliberately inclined Mun orbit. In low orbit the last material bay is used and one of the goo containers. Here we discover that you can't see much from inside the pod making crew reports from Mun orbit rather limited. However much more detailed reporting can be done from outside the cockpit, so a number of EVAs are done to collect information about the Mun's craters and terrain for a future landing. Apart from my mistake with the power requirement for crew reports I also overlooked the way the Mun is tidally locked to Kerbin, which if my observations and understanding of orbits are correct meant that my inclined orbit didn't seem to help me at all in covering more of the Mun's surface.

Return to Kerbin was straight forward, I successfully aimed for a water landing so the last goo container could be exposed there.

Recovery of everything yielded 594 science in total. I seemed to do ok without fuel lines so I put them off for one more mission, instead going for more sensors by unlocking Electrics (solar panel), Advanced Electrics (solar arrays) and Electronics (Double-C Seismic Accelerometer) along with Space Exploration (2HOT Thermometer). I also discovered that with the save file edited to turn off the ability to delete items from the observatory it also seems you can't recover directly from there either, I had to 'fly' the debris I left on the launchpad in order to recover the materials bay.

• Project Gander completed.
  
• Orbited Mun.
  
• Collected 594 science.
  
• Unlocked Electrics, Advanced Electrics, Electronics and Space Exploration.
  
• 28 science saved.
  

[Dave Kerbin]

And here is your Gander side note. While I don't use mechjeb or any other mods to help fly, I did use Excel to plan and old fashion pen and paper to track things. With all the staging on this flight and the danger of losing an experiment before it was recovered I went so far as to make a quick checklist for the mission. The bit scrawled at the bottom is telling me I need to keep at least 15L of liquid fuel so that I can break Munar orbit and return home safely (it can be done for less but I wanted a good margin of safety since I've got a live Kerbal and there is no quicksaving to bring him back).

[Sesni]

Hmmm. I shall be reading.

[KeithStone]

You've got my interest....

[Rhyunix]

A very well planned, detailed program- I shall follow this with great interest

[Dave Kerbin]

Cheese 1

The first mission in phase 2 is to land on the Mun. Since Rayfrod flew all the phase 1 missions new recruit Gregfield is going to handle the manned missions in phase 2. In phase 3 I think there might be good reason to need them both to fly.

The ship doesn't have as much complex staging as Gander 1. One area I was concerned about was using solid boosters, I have this idea in my head of the little reaction wheel in the Mk1 pod being too little to keep the ship from tipping over in flight. To get around that I reused the center LV909 engine that worked on Gander 1, only this time it won't be carrying much fuel because I will be using it for stabilization instead of added thrust. So instead of figuring out the delta-v I just added its wet weight as payload for the solid booster portion of the flight and its dry weight as payload on the main liquid booster. The stablizer carries a T200 fuel tank (90L) for operation and I can throttle it as needed to maintain control during the solid boost phase before the throttle is turned up to 100% for the liquid booster stage (which should quickly use up its fuel and leave it as dead weight until the orbital stage takes over).

While this is his first mission Gregfield does have a mission checklist to follow so he should be ok. Unlike previous flights Gregfield will be an active pilot during the first part of the launch since he will need to figure out how much throttle is needed to get the stabilizer engine running strong enough to counter any imbalance from the solid boosters, and if needed adjust his pitch and yaw to bring it back to center. He also has two brand new instruments that he will be testing on this mission, the 2HOT Thermometer and Double-C Seismic Accelerometer. Both of these instruments are calibrated before launch.

Lift off goes smoothly, meaning there where no explosions, but the solid boosters do flex the body work a bit, causing the top of the liquid stacks to angle inward and the bottom to stick out. The more pressing concern is that there is quite a bit of spin. Gregfield is getting dizzy and the ship is starting to list to the side. Incrementing the throttle slowing doesn't seem to be correcting so while Gregfield can still see straight he jams the throttle to 100% which regains control of the ships attitude. 32 seconds into the flight at an altitude of 2km the solid boosters are ejected and the liquid boosters take over. This greatly increases the level of control leaving only a little spin and lining up the navball correctly.

Learning from the explosion that almost destroyed Gander 1 the checklist is very careful with how the booster stages are discarded. The center stabilizer tank is kept on and will only be released after the radial tanks. The 6 engines running at full throttle put out a huge cone of fire that must be visible for a hundred kilometers.

As Gregfield passes 50km on his gravity turn the booster stage fuel is almost exhausted and he is getting ready to cut it loose and coast toward his final burn. There is still some spin but since attitude is functioning correctly no correction attempt is made. This time there is no third stage center booster, only an orbital engine that we don't need to figure up for a few minutes. The radial stacks are ejected first, then when it is confirmed they are clear the stabilizer is kicked off to clear the orbital engine. This time the problem with Gander's seperation is more apparent, as the radial tanks flip end over end, coming dangerously close to hitting the center section. These observations by Gregfield will be important in designing future missions. The orbital burn and the munar insertion are done using the orbital engine and are pretty straight forward by this point. The orbital engine has one last official use, which is to perform the capture burn at the Mun.

Gregfield arrives and establishes a 30km orbit above the Mun with about 90L of fuel left in the orbital stage. He begins searching the surface for a good landing site for this mission which will involve two landings - one landing in a crater and one landing outside for a sample comparison. On the side of the Mun facing the sun there is one rather prominent crater and he begins descending into it. Gregfield is trying to land close to that dark gash thing in the center right. From this angle it seems he will miss it but from a different perspective it is clear his descent path is a fraction north of the gash rather then a big miss south.

The orbital section has done most of the work in slowing down the lander, it is nearly a straight drop from here. With all the fuel Gregfield can be very careful with his landing and stay slow during the descent. Touchdown is at 3.6m/s.

The lander actually has two sets of landing gear. The regular landing gear provide some cushioning, but the goo containers provide a secondary set of landing gear to protect the engine. In the event that the science modules couldn't easily be accessed there was a procedure for folding up the landing legs to bring the ship closer to the ground.

Gregfield gets out to explore the crater. His EVA includes the classic flag planting and taking of surface samples. It also involves using one of the access ladders to collect samples from the science bays. Something that is learned is that the small science instruments can be reset for free (Gregfield can take the data and the instrument can be used again), so we didn't need to carry as many as we did.

The next phase of the mission involves a suborbital hop to the outside of the crater. I've never done this before (except for on Gilly where the gravity makes any thrust nearly orbital) but I have a good idea of what forces will be involved and what Gregfield should watch for. It begins with a regular lift off and a turn 45 degrees east, but once the AP hits 5km Gregfield follows his instructions to turns all the way horizontal and puts on speed until his suborbital trajectory puts him outside of the crater. As we coast along we get a good look at what that gash was - a narrow mountain about 3.5-4km high. Fortunately Gregfield is flying parallel to it so he doesn't need to gain altitude to avoid the cliff face.

The next step is the landing. Gregfield is already aware that most of his velocity is horizontal and he needs to kill that before touching down. However he also needs to avoid losing too much altitude while he does it. Passing the final lip of the crater (after the main cliff face there are 2 smaller depressions to avoid) thrust is put on. We are traveling 200m/s and above 500m from the surface, the crater was almost 2km deep so we are coming up on the ground much faster then we left it. Gregfield is following the procedure and trying to angle his braking maneuver to keep his vertical speed dial at zero. Gregfield manages to zero out his velocity a short distance from the next crater (the cliff edge is a little difficult to see but it is a steep drop off).

It is another smooth landing but with one small problem. On landing Gregfield discovers he has just 10L of liquid fuel left in the tank (the hop burned 42L). He's not in danger of being unable to get home, but that landing was very risky with that much fuel, if the orbiter hadn't done so much of the work during the first landing he would have run out of fuel while traveling 720 km/h just a short distance over the Munar surface. The problem was the checklist which accidently omitted a crucial step after the first landing, transfering the 90L of fuel stored in the side tanks to the center tank (the engineers haven't invented fuel lines yet).

The fuel is transfered and similar science and EVA operations are done as the first landing. Gregfield uses his jetpack to return to the command pod. In his frustration over the checklist he makes a spelling mistake on his field report.

The lander lifts off and immediately discards most of the science equipment and the empty reserve tanks. Gregfield is following the mission plan to enter a polar orbit around the Mun, with the intention of coming back into polar orbit around Kerbin and landing on the ice. You can see Gregfield coasting to AP with a good view of the two landing zones, giving a better sense of the geography.

However once Gregfield is in orbit I realized this plan wasn't going to work and what it is that I had overlooked when thinking it up. I made the mistake of only thinking in terms of the Mun's frame of reference. In that frame I was moving north to south which I assumed I could use to get into the same orbit around Kerbin. But the Mun is also moving in relation to Kerbin, east to west, and moving much faster then my little Mun orbit. As a result the only way I could manage a polar Kerbin orbit would be with an enormous amount of delta-v (almost the entire velocity needed to maintain such an orbit).

So a straight forward return to Kerbin is made resulting in a landing in some boring grassland (object in the upper right is the discard service module) east of some mountains and west of the big crater gulf. A seismic and temperature scan are done but there is no point in a surface sample or EVA.

It was a good science haul, with 947 science earned in total. All of the remaining science instruments where unlocked and the tech leading up to and including fuel lines where unlocked.

• Project Cheese completed.
  
• Landed on the Mun in two places.
  
• Collected 947 science.
  
• Unlocked Advanced Science Tech, Advanced Rocketry, Fuel Systems, General Construction, Flight Control and Advanced Exploration.
  
• 40 science saved.
  

[Dave Kerbin]

Cheese Sidenote

I'm getting a lot of science and blowing through the tech tree much faster then I expected. I created this mission list so that I'd be forced to use limited parts for missions (but without just making an arbitrary list of allowed items) specifically after seeing a forum post asking if you could land on Duna without LV-N's or Mainsails. But even with me spending on just about everything else it's going to get real tough to find an excuse not to unlock the LV-N before Project Martian. Project Mint is practically ready to launch, since Cheese 1 only needs minor alterations to the science loadout to become Mint 1 (and will have even more spare delta-v), and promises to bring in even more science (probably close to 1500). I can spend a lot of that on probe parts, maybe ion drives, but then I'll have the science from Project Berry.

I'm not going to abandon this career but maybe I should forget about trying to do a low tech Duna run on this file and play it as normal (with LV-Ns if they get unlocked). I can then start a seperate career, perhaps run in parallel, with a tigher mission structure where each mission is a manned mission to orbit and land on a different body and safely return to Kerbin: First is orbit and land back on Kerbin, then go to Mun, then go to Minmus, and for mission 4 go to Duna without nukes or other advanced stuff.

[Andersenman]

In his frustration over the checklist he makes a spelling mistake on his field report.

Hahaha, and that's not the first misspelling in his reports:

(should be 'heavier than', not 'heavier then'.)

Anyhow, great reports again. One question: You always mention you plan your crafts, but could you perhaps describe your planning process a bit more, perhaps in a separate post? I'd like to know what you consider and how that transfers into your designs.

Thanks!

[Commander Zoom]

Great thread so far.

[Cashen]

Nice thread. This is the first display of science and career mode that's made me consider playing it at all, though I think I'm too committed to my sandbox game to start another.

I especially like the animated GIFs. I may need to incorporate that in my own work.

[Dave Kerbin]

Mint 1

The design for Mint 1 isn't new, it is a copy of Cheese 1 which already matched all the delta-v requirements, the only changes are some science instrument upgrades. The inert nose cones on the 2 science pods have been replaced with Sensor Array Computing Nose Cones and the thermometers on the side have been replaced with brand new instruments, the PresMat Barometer and the Negative Gravioli Detector. The command pod now has one of each of the small instruments. The last change is the lander now has a ladder.

After some barometer and gravity calibration on the launchpad it is time for lift off. Having used this ship before things go easily, the only change to the mission checklist at this point is that the nose cones take readings in the lower and upper atmosphere instead of the thermometers used on Cheese 1. Once in orbit an EVA is performed to collect all the data and return it to the pod. At this point the first real change in the mission plan is performed where instead of immediately plotting the required burn to the Mun/Minmus Gregfield instead begins performing a survey of the planet with the negative gravioli detector. It is immediately apparent that the easiest way to do this is to measure using the instrument on the command pod so that Gregfield can simply open the hatch, grab the results and hop right back in. The survey only covers the equatorial portion of Kerbin, so no readings are taken of the Tundra or Ice Caps but 6 other areas are scanned.

After an orbit to perform the scan a trajectory out to Minmus is plotted. There was actually an opportunity to do a Mun flyby on the way to Minmus, which would have provided a chance for a few grav readings at no cost. However it wasn't in the mission plan and I didn't want to take any risks with Gregfield. With the default conic prediction I couldn't see details about the projected Minmus encounter. It still might have been interesting to risk it though not for the science (this was not the only opportunity for science that was passed over on this mission)

The navigation was still done a little seat of the pants - no inclination change is made so the encounter with Minmus is going to be off center. The orbital stage has all the delta-v needed (Minmus requires more for an encounter but less for capture). If we don't capture at Minmus we will have an encounter with the Mun instead.

On the way out from Kerbin a few more gravity readings are taken as the planet rotates under us, giving us a few high orbit values.

Capture at Minmus uses up about half of the orbital stages remaining reserve, putting the ship into a 1400x19km orbit for surveying. Not much is really seen from high orbit - lowlands, midlands and flatlands - so Gregfield doesn't go around for another pass, instead bringing it down to a circular orbit. After some more observations the orbit in inclined a bit more to bring the ship over one of the low mint green areas where we want to land.

The orbital stage has enough fuel left to completely brake the orbit. This is useful since unlike the Mun the surface does rotate under our inclined orbit, putting the landing zone near the edge of the area we wanted. The orbital stage is ejected 8km from the surface so we can begin slowing our descent for a smooth landing. It provides one more useful function by providing a visual indicator of how close the surface is.

This is the third time this design has landed and it's on an incredibly flat site so there where no surprises. The ladder does make it a bit easier to get in and out.

After a brief stay it's time to check out the higher ground. This time the checklist includes a fuel check, but the center tanks have plenty so there isn't even room to transfer from the side tanks yet. We might have upgraded the design by adding fuel lines to automatically transfer fuel but we didn't. Our destination is that flat plateau in the top center of the picture. Midway there a little thrust is used to gain altitude to make it over the cliff edge.

Landing is fine but the legs don't seem to get a good grip on this soil of the plateau, the lander wants to wobble like an uneven table. Toggling SAS on and off gets the legs closer to the ground but it's still wobbling. To solve the issue the primary legs are retracted letting the lander rest on the secondary landing gear (goo canisters), then once the lander is settled the legs can be extended again and hopefully take an even grip. The procedure seems to work.

Now it's safe to get out and do science. After the EVA the fuel tanks still don't have space to transfer the sideboard fuel without creating an imbalance.

The earlier survey indicated several biomes and so far we've landed in the lower flats and the lowlands. Even though the goo and material bay are unavailable for use we could get several hundred points of science by exploring elsewhere. Gregfield takes off and heads toward an area that looks promising with some small hills inbetween the various higher plateaus. Unfortunately this turns out to be more of the lowlands. Gregfield could have gotten and out and at least planeted a flag but by this time he had already been up for almost 2 days perform a pair of orbital surveys and now 3 landings. With lots of fuel he took off again this time flying further north.

Still in the lowlands. There is enough space to transfer fuel now, almost entirely refilling the center tanks. If Gregfield wasn't so tired he could probably do another 4 landings with all this fuel.

With Gregfield exhausted mission control gives the ok for him to come home. Lift off is into a polar orbit from where gravity scans reveal he was just short of the polar biome. In theory there is enough fuel that he could continue around and land on the next orbit but the decision to come home has already been made and Gregfield is going to stick with it. After breaking orbit the fuel is put to use accelerating Gregfield's return. He takes a snooze until mission control wakes him up for reentry.

The mission returns 2378 science. How I decide to spend all that will have to wait for a side note.

• Project Mint completed.
  
• Landed on Minmus in four places.
  
• Collected 2378 science.
  
• Science investment coming soon
  

[Andersenman]

Midway there a little thrust is used to gain altitude to make it over the cliff edge.

[Dave Kerbin]

Ok, I got some bad news.

The budget kommittee just got finished looking at the mission report for Mint 1. They are pleased to see the goals they set out where completed and that so much science was returned. But they are very not-so-pleased that the mission, which already had a stretch goal of a second landing (which was not a part of the kommittee's requirements) took on 2 additional landings and still had over 1000kg of fuel left in the tanks. With the cost to launch just 1kg of cargo into low Kerbal orbit they see this as a massive waste on the part of the kerbal space program. In their words this space program was designed to send Kerbals into space, not money. If the program is to be saved they want to see some serious cost cutting.

For starters the kommittee has decided that the budget for phase 2 (small steps) is basically spent at this point. Project Berry will need to be completed using whatever parts are leftover in the VAB from the previous rockets and any remaining parts will need to be bought using the office supply budget. Furthermore the kommittee has caught word of the 'nuclear engines' now in development. These sound very expensive, especially with the rising cost of refined kranium and klutonium. They have decreed that a limited number of nuclear engines will be purchased for the program and will be dependent on the successful completion of each phase. For the next phase of the program, Great Journeys, they will provide the budget to purchase exactly one nuclear engine. For the phase after that (Inquisitive Minds) they will provide the budget for 2, and for the last phase they will provide the money for up to 3 more nuclear engines.

Not wanting to stir things up any more the design office only invests in 2 new science ventures, Precision Engineering and Unmanned Tech. Unlocking anything else would be useless since there isn't the budget to buy anything much larger then a photokopier on project Berry.

There is now 1958 science saved for later.

[Dave Kerbin]

Berry 1 is outside Kerbin's SOI, but the mission is on a bit of standby until I figure out how I'm going to deal with this bug. Unfortunately it has a big effect on one of my instruments and could mean a choice between landing safely and collecting data.

Edit: I think I have a method to deal with it, basically it's transmission spam only with more work and I won't be able to get 100% of the science that transmission is normally supposed to give. I'm not yet sure of how big a loss I'll be taking on the main instrument but it looks like the factors involved will mean a lot.

Edited January 1, 2014 by Dave Kerbin

[Dave Kerbin]

Berry 1

The goal of Berry is to investigate the surface of Eve with an unmanned probe, however the project has been subjected to harsh budget cuts after the fallout of Mint 1. The actual mission itself has experienced some out of game issues - I discovered that trickle charge transmissions don't seem to want to work one way or another in .23 (either a bug or an intended feature that doesn't quite work as intended). I also had an issue with recording. While the recording animation was playing through the whole mission and I stopped it correctly before exiting I found out that afterburner had frozen about 40 minutes in. Killing the process let me access the video file which stops a little while after the first aerobraking, leaving me with a lot of lost footage that I have no way to recover (I can't even replay the mission since I'm playing a single save file).

With the budget for Berry being essentially nothing the space center has to make do with what is sitting around and what they can put together with the office budget. They can't even afford to pay the gantry crew or operate the crawler, so instead it falls to Rayfrod and Gregfield to get Berry 1 on the launchpad. The setup starts at 5am before the sun has come up. Rayfrod and Gregfield manage to unlock a side door and begin gathering up used engines from the R&D office. At just over a ton each they need to be rolled one by one up to the launch pad and stood up. Work carries on to about 10 and then its over to pickup the probe. The parachute seems to be new, but the instruments look like they've been taken from the simulator and the unique fuel tanks, which neither Gregfield or Rayfrod have seen before, look suspiciously like metal waste baskets welded together and a life preserver from the zero gravity pool wrapped in plastic.

Did we really need space suits for this?

As noon approaches Berry 1 is completed on the launchpad. Time for lift off!

Ok, zoom in a bit. Now time for lift off.

No fancy fuel lines or anything here, after the powerful first stage exhausts its fuel supply it is released and the 2nd stage fires up to take Berry 1 to orbit.

With a 71x73km orbit established and 12.9L of fuel left in the booster tanks it's time to plot a course to Eve.

The boosters give me just over 5 seconds of burn before they are discarded for the main engines. This is a 4 minute burn for Eve and due to the angle and length of the burn I actually cut through the very top of Kerbin's atmosphere on the way. From the look of the exhaust and the sound I'm not sure if those are real rocket engines or just office fire extinguishers taped to the side.

Once outside of Kerbin's SOI a small adjustment is used to refine the Eve encounter to 70km. That will be further adjusted once we reach Eve's SOI. One small issue is transmitting science - if we don't have enough power then the transmission speed slows down while it waits to recharge between each packet. However after the first one we stop getting science. If we check the missing science seems to be available to be transmitted on a second try, but it will transmit 0 science instead. The only way around this seems to be by time warping, which slows down the transmission rate relative to the actual in game clock (transmissions still take the same amount of real world time, but the in game clock is moving faster) while the solar panels recharge using the game clock (so more power is recharged between packets, preventing the battery from reaching zero and causing the bug/'feature'). It's far from an ideal solution and I will be unable to fully transmit some of my major findings (I won't be able to use time warp for the sensor nose cone in the atmosphere, which means despite planning on plenty of time I'll get about 10% science instead of 35%).

Once we reach Eve the PE is lowered to 59km for aerobraking. I want to get into orbit so I can choose my landing site, it needs to be on the daylight side and over land (the probe can land in the water but this disables 2 major instruments).

It takes drops of fuel (7m/s) to adjust our orbit. At this point it seems that afterburner had silently frozen up and wasn't actually writing video any more, just showing the spinning record icon in the corner of the screen. So the only pictures I have from this point on are those I went back to the planet and snapped and the only numbers I have are those that I remember or scratched out to help adjust my orbit. The descent/parachute phase is lost.

After first aerobrake took my AP to 11500km I adjusted the PE to 74km for another aerobraking pass. This lowered AP to 4800km. PE was raised to 85km and two more passes where done to lower the AP to 3800km with an orbital period of an hour or two. From there PE was raised to 120km to allow for 100x time warp so that the larger continent could rotate around to the day side.

At that point much more delta-v (about 150m/s from a potential 350m/s left in the tanks) was used to setup a somewhat straight line for the big continent so that no matter how drag affected the path I would stay in the sun and hit solid ground.

My plan was to run the thermometer and barometer in the upper atmosphere and transmit their data, then recharge while still falling before transmitting as much as possible with the nose cone from the upper atmosphere. However with the changes in procedure I missed storing all the readings at once, and because of the steep angle I fell right down to Eve’s lower atmosphere before I got around to taking a nose cone reading. So instead I stored a reading from the lower atmosphere before taking and transmitting readings for the thermometer and barometer and again.

As I came in for a landing with the chute opened I followed the planned landing procedure which was to enable SAS and then use the W key to tilt the probe slightly again the parachute cord. This way when I lightly touched down on the nose cone (about 4m/s I think) the probe tipped over in the correct direction. The ROUND-8 fuel tank (orange tube) was placed to protect the probes sensitive equipment from contact with the ground. With the probe tipped over correct I had the antenna facing upwards, 2 of the main and 1 of the backup solar panels exposed and all the instruments accessible.

Now the nose cone reading could be transmitted, followed by a full suite of ground readings after a recharge. Total science was less then expected, with 665 collected in total.

• Project Berry completed.
  
• Landed probe on Eve
  
• Collected 665 science.
  
• Science investment coming soon
  

[Andersenman]

Aside from Tony Probe, this is easily the smallest interplanetary craft I have ever seen!

[team.leit]

Aside from Tony Probe, this is easily the smallest interplanetary craft I have ever seen!

Same here!

[Dave Kerbin]

I considered using ion power but it was just too heavy - the mass of an ion engine, tank of xenon and a single XL solar array weighed more then my entire liquid fueled probe including all the instruments.

Specifically here is that prototype version which once in LKO weighs less then the lightest manned pod (0.57t I think). The final Berry 1 probe weighed 0.83t fully loaded I believe.

This prototype version is lighter because it removes the heaviest component besides the fuel, the parachute. Instead it had ultralight landing legs and with the higher ISP engine and lower weight it had an extra 220m/s of delta-v which was to be used to land it after hitting terminal velocity on Eve.

The lighter design also had a simplier launch system thanks in part to the probe's engine having much more thrust. This meant it was practical to tie in the launch boosters fuel supply and use the probe engine to assist in lift off. The essentially SSTO design required a little more fuel (the Round-8 tanks) but saved a lot of weight because it didn't need decouplers or the higher thrust but much heavier LV909 engines.

Ultimately I scrapped this version because I knew that I had little hope of doing a powered landing on a high gravity planet, especially with a probe that weighs almost nothing and an engine with a huge amount of thrust making it very difficult to finely control my descent speed. With 220m/s of fuel vs about 85m/s terminal velocity I'd really only get one chance to get it right. I did look into using the barometer as a makeshift radar altitude meter - if it was accurate enough I could have made a stab at doing the landing mathmatically like I did here.

[Andersenman]

[...] I could have made a stab at doing the landing mathmatically like I did here.

Would you mind explaining such a calculation here?

Thanks!

[Dave Kerbin]

Would you mind explaining such a calculation here?

Thanks!

The challenge was to land the largest mass using the 'fewest' engines (no parachutes). Scoring was based on a value for the planet, engines used and final mass of the ship. The way the scoring system worked the Mainsail was the obvious choice - in order to land you need a TWR > 1 so you can easily determine the maximum starting mass of a lander. Dividing by score the Mainsail was had a better ratio then the other engines by a large margin (large enough to ignore any differences in ISP). Planet wise Kerbin had an atmosphere and that meant you really didn't to burn as much fuel to land, since drag would remove everything but terminal velocity. Score wise Eve was better (scores seemed to be based on gravity) but Kerbin was obviously much closer.

The basic strategy I assumed is that you want to burn as little fuel as possible (to keep the weight up) which meant you wanted to counter the minimal amount of velocity. Every second that you are falling gravity is adding to your velocity, so you want to burn for the shortest period possible. If you 'hover' you are just providing gravity with more time to add velocity that you'll need to kill later. So my calculation was determining when I should turn on the engine so that under a continous burn I would be at landing velocity (<12m/s) just before I touched the ground.

First I got some numbers. My ship would be just under 153 tons (1500 kN / 9.8m/s) in order to have the minimum TWR. From the wiki it would consume fuel at a rate of 109.11 l/s at sea level. Since I would be near that I decided to just take that as a constant value (I figured that the human factor would add a much larger margin of error then the fuel consumption difference). Finally I needed my terminal velocity, which I figured by tossing my ship up 5km and letting it fall down.

This is a rough recreation of my spreadsheet, some of the initial values are approximate but the final values seem to be close enough to match. My method won't make the higher math folks happy, I've forgotten most of my calculus which could have probably boiled this down to one nice equation without all the errors I've introduced.

In the first column A you have how much time has passed. The second column is how big of a time step I'm going to use which is where the calculus folks will cringe. The smaller a value I use here the more accurate the results. KSP experiences the same thing, since it calculates everything in descrete steps. When you use physical timewarp (2x-4x) you are increasing the size of those steps so that fewer have to be done to cover the same amount of time at the cost of accuracy.

Column C has my initial mass and every row following is carrying over the value from the New Mass column (L). D, E, F and G are constants for the engines thrust, fuel use, gravity and a calculation of how many tons of fuel are burned for each time step. Column H is my current velocity, which is initially terminal velocity and then carries over from the last rows New Velocity value (K). Column I has my calculation for the ships current thrust, which is just engine thrust divided by current mass. The acceleration (J) is the difference between thrust and gravity and new velocity (K) is the old velocity plus acceleration. New Mass (L) is the difference between the old mass and the fuel burned and finally distance is a running total based on the velocity multiplied by the time passed - this is how much vertical distance the ship has fallen since the burn at terminal velocity started.

Using range copy and paste I can duplicate this to hundreds of rows in a single step which is the brute force math part.

Scrolling down I find that in just over 15 seconds I should reach landing velocity. The important figures are that by that time my mass will be around 130 tons and most importantly I will have fallen 1400m. Armed with that figure I now have a close approximation of what distance above the ground I should start burning if I want to be at the right velocity when I reach it. Conveniently the radar altimeter has a notch for 1500m which provides enough breathing room to account for human reflex time and the margin of error inherent in my calculations (time steps, fuel usage assumptions, terminal velocity assumption, perfect pitch, etc).

In my low altitude tests these numbers worked correctly. I started a burn at 1500m and I typically stopped just before I hit the ground, letting me adjust the thrust a bit and land with 120 tons of mass. For my real orbital drop I was a fraction late which put me even closer to the ideal numbers, hitting the ground at practically the exact speed (I had no chance to lower thrust, just cut it when the landing gear hit) and landing with 125 tons of mass.

[Dave Kerbin]

With phase 2 complete I'll be starting on phase 3 soon. Phase 3 will work a little bit different - I'll be planning out all 3 missions at once since they will launch in sequence and with varying travel times they will overlap as to when they land and return. I'll also be trying to keep the budget down in a somewhat realistic fashion. Expect the manned Duna and Dres missions to share a lot of common parts in the name of cost savings.

I've expanded the tech tree with what I think I might use (or what is required to get it). There is 423 science left to spend.

Unlocked techs are:

Heavy Rocketry -> Heavier Rocketry, Specialized Control -> Nuclear Propulsion

Advanced Construction -> Specialized Construction -> Advanced Metal Works

Landing, Ion Propulsion, Advanced Unmanned Tech

Edited January 6, 2014 by Dave Kerbin