Dave Kerbin

Mod Virgin - Career playing with "Better Than Starting Manned"

Recommended Posts

I've logged my career play here on the forums, playing .22 and discovering the tech tree and how science works for the first time, then playing .23 and trying to roleplay a budget (and finding it was a bit too easy once you knew the tech tree) and finally playing with only probes. I wanted a new engineering challenge, one that encouraged doing reasonable missions but on limited resources (like going to the Duna in under 22 tons), rather then massive goals like returning from Eve. I had a couple of ideas and I've already played out the first of them, the probe only career. My other options including doing another stock career but with special roleplay restrictions as I outlined here, doing an IVA only career, or doing some kind of mod career using TAC life support, deadly reentry and maybe some other realism mods.

While asking about stock restrictions the user Death Engineering, who sometimes frequents my career file, suggested the mod Better Than Starting Manned. This mod looks really neat - a complete redo of the tech tree, some of the science mechanics and as I found out the parts are basically brand new too so all my old spreadsheet designs and assumptions have to be started over from scratch. It also has a form of life support and is designed to work with Deadly Reentry Continued.

So this is what I'm going to be doing, I'll be playing a fresh career with the mod Better Than Starting Manned along with the prerequisite Deadly Reentry Continued (everything else is pure stock). This will be my first time playing with the mod. I have no foreknowledge of the tech tree, parts or mechanics beyond what is in the first post of the mods thread and deadly reentry's. This will be an entirely 'new player experience' (granted from a player well versed with stock KSP) complete with all the mistakes.

There will be dead kerbals.

I won't be playing with any imaginary restrictions (other then avoiding any exploits like infinite gliders or silly tricks like stacking solid boosters to create decouplers) so ships can be big if they need to be. My one goal which everything else will support is to reach Eeloo, plant a flag and return to Kerbin safely.

Ask any questions you want, I'd be happy to answer or clarify anything.

Comment or click the star if you like this thread.

Update, second playthrough

I've completed the original goal and have started a playthrough with the new version of BTSM, rebalanced and with new parts for KSP .23.5. You can skip straight to this new playthrough by clicking here, or just read through the original playthrough first and you'll continue into the second.

Update, third playthrough

With the second playthrough's goal completed there is now a third playthrough, utilizing the newest version of BTSM which introduces launchpad weight limits. My goal is to make a manned mission to the Mun using the absolute minimum of BTSM tech and the smallest launchpad weight limit.

Edited by Dave Kerbin
  • Like 7

Share this post

Link to post
Share on other sites

Alpha 1 - 4

BTSM starts off with a unique tech tree. As you can see there is no capsule, not even a liquid fuel rocket. Just a solid booster, probe, antenna and 2Hot. The first thing I noticed in the VAB was that the weights are different - a lot of things are heavier so you no longer have science instruments weighing a negligible amount. The Stayputnick is heavier but it now actually has 10 minutes of battery life like the description says. I also found out that you can't tweak the thrust on solid boosters, so after calculating that I wanted 25% thrust for optimum altitude I couldn't do it. There is only one speed and that will be fast. On the launchpad I found out that you no longer get science on the ground - in BTSM the kerbals seem to have already explored that far.


My first launch gets off the pad and begins turning north, slowly tipping over. It becomes clear it will not last long and as it passes 90 degrees, now tilting down, I start transmitting some temperature data about the lower atmosphere. The transmission ends just 1.08 seconds before the probe hits the water 50m from the shore and is destroyed.


4 science isn't enough to unlock anything, so I try flying again but with SAS turned on. It turns out the probe doesn't have SAS or a reaction wheel and it crashes, without the ability to perform any new science. So for a third launch I try to get the antenna and 2Hot placed to balance each other. This doesn't work either. Then I remember that the weights are different - I need 2 antennas and 2 2Hots to balance. This time it works and the 4th Alpha launch manages to reach the upper atmosphere and get 4 more science.


After it comes down I can unlock the next item in the tech tree, Basic Rocketry. This gives me the bigger solid booster rocket, a barometer and finally what looks like the Double-C but is actually a small (50em) battery.


Share this post

Link to post
Share on other sites

Beta 1

With the knowledge I gained from the Alpha series I have some idea what I'm doing with Beta. I load up on batteries and add new new barometer to my ship which is now on top of the bigger solid booster. The need to balance weight differently (the science components not sharing the same weight) leads to some more interesting visual designs.


The flight goes easy, reaching 30km. The barometer takes much longer to transmit then the 2Hot, though it also provides double the science (8). I unlock Survivability which gives me an unpressurized cockpit and the small parachute.

Edited by Dave Kerbin

Share this post

Link to post
Share on other sites

Charlie 1 - 2

Being the first manned mission I should take a moment here to explain that for my career files I make a modification before I start playing - I edit the save to turn off respawning (dead kerbals stay dead) and I remove the 3 orange suits (Bill, Bob and Jeb). This way all my kerbals are fresh and new, instead of having kerbals from my other careers mysteriously show up.

My first kerbonaut is Gusmin Kerman. You can see he is very brave, and just dumb enough to get into a ship that's nothing more then a cockpit on top of a solid booster rocket. The launch goes well and he starts transmitting a crew report. The transmission is going really slow - even with 8 batteries there just won't be enough charge to send even half of it. At 10km up the ship is just about to run out of charge when another problem appears. Gusmin needs air to breath.


5 science is received for the data Gusmin transmitted before he passed out. The ship falls back and lands in the parking lot.



Another brave pilot is found to take the ship up again. Since the problem started a little past 10km and the ship started falling back soon after it's just a matter of not going that high.


On the way up it becomes apparent that there is no way to actually steer the spaceship. The crew report is stored, knowing that there isn't enough charge to transmit it. At the last minute the parachute is deployed in an attempt to slow down the ship but it's too late. Billy-Bob Dan is tragically killed though his ship is the first to land safely back on Kerbin carrying his last written words. The +15 science (with +5 from Gusmin) is enough to unlock General Rocketry. We get a different version of the GravMax (from the description it only works in low orbit), the T800 fuel tank and a unique LV-T15 series rocket, not to be confused with the T30.


Share this post

Link to post
Share on other sites

Very entertaining! I've been curious about Better Than Starting Manned myself, but always been too scared to install it! :P

Share this post

Link to post
Share on other sites

Delta 1 - 2

I'm honestly not 100% sure what my goal with Delta was. BTSM is a very interesting change to science in KSP. If you've ever browsed the question and answer forum you'll find someone new to KSP asking where they can get science. To anyone experienced it's easy because there is plenty of it at the beginning, Kerbin is covered in small bits of science. BTSM puts experienced players in that same position. I have used the 2Hot and barometer in the upper and lower atmosphere, I can't fly a kerbal into the upper atmosphere without killing him and the GravMax can only be used in orbit. If I could figure out how to land safely I might be able to try a terrifying low atmosphere EVA. In short it doesn't seem like I have any experiments left, I actually thought a few times I might be running into a tech tree dead end. BTSM seems to do a nice job making you really work for the next bit of science - you have to be original.

So anyway I think my 'goal' with Delta was to figure out what I could do with liquid rockets. Maybe I could get into orbit or something so I attached all my current instruments to a probe. Or maybe I just didn't want to kill another kerbal without advancing a bit so they would at least die in a new way.

So I launch off and there are two problems. The first is that I don't get a perfectly straight up launch - the nozzile of the liquid booster just isn't as stable a launchpad as the solid booster - and that means I slowly tilt over. The second problem is that extra bit of smoke you see coming off a bit of an angle from my main exhaust. That's bits of the nozzle assembly melting. The T15 exploded a few seconds after that smoke started appearing. Without the engine the rocket did not fly.


The second Delta added 2 large and 2 small boosters, with the large ones forming the launch platform. The hope was that I could stage them and maybe it would stay stable and have enough to reach orbit. Unfortunately it did not fly straight which told me my main problem now was making my rockets stable. I needed science so I could unlock useful parts and Delta wasn't going to provide it.


Share this post

Link to post
Share on other sites

Echo 1 - 3

With science for stability a priority I turned back to manned flight. Maybe if I could safely land a pilot there would be a science reward. Wilrod steps up to pilot Echo 1 which will attempt a flight using liquid fuel engines.


The first problem of the flight is stability again. The rocket tips as it flies and I'm forced to cut engines as it turns beyond 90 degrees pointing down instead of up. The parachute is deployed but when it fully opens the forces applied rip the ship apart. I'd expected the fuel tank and engine might be taken off but it falls apart completely, leaving the pod to crash.


Huddo Kerman is up next. He tries to burn as much fuel as possible, taking the engine right up to the red line but stopping on a complete overheat. It isn't enough. The explosion you see is the parachute, which has ripped off the pod on deployment, smashing into the rocket and leaving a fireball behind it as it falls.



Hanemone Kerman is up for Echo 3. Piloting isn't going to fix things, so I go for more parachutes by adding 3 radial tanks, each with an engine and a parachute.


The flight starts out really slow - with all those engines I run them at really low throttle, lifting off the pad slowly but stable in the hopes of using as much fuel as possible. The ship does start to turn as I climb. When it gets close to horizontal I turn the engines up to maximum, deliberately running them hot enough to blow up in the hopes of burning even more fuel and 'removing' the weight of the engines.



The ship is actually flipped around a bit by the uneven loss of the engines (2 radials explode first, then the remaining one, then the center engine)


The chutes open and the ship finally rights itself. When they fully deploy it holds together.


Hanemone is the first kerbal to survive a flight, though the hatch is blocked and he can't get out. Unfortunately it's not worth very much, just 0.8 science.


Share this post

Link to post
Share on other sites

Foxtrot 1

Since I didn't get any substantial amount of science I tried out a varient of the last Echo ship (it could have been an echo series itself). It added solid boosters at an angle, on the idea that they would add some spin stabilization. Johngan Kerman is the pilot. It barely passes 200m.


And then they go really not well when the mass of the fuel tank brings the capsule down at 16 m/s, killing Johngan. The Foxtrot series is abandoned.

  • Like 1

Share this post

Link to post
Share on other sites

Golf 1 - 2

After failure I went back to an unmanned ship. Seeing some opportunity in Delta 3 I decided to try and copy the parachute design - until now I couldn't return a probe because there was nowhere obvious to place a parachute. But if I mounted extra radial engines I could put parachutes there. I decided to see if I could get some science from return a probefrom the upper atmosphere or maybe even space.

The idea was for the 2 radial boosters to fire first, then the center one would take over when there was less solid fuel to lift. However I had my first encounter with deadly reentry when the parachutes decided to explode from overheating. It wasn't a complete loss though - the ship had enough inertia to reach over 90km before it came back down and crashed. An interesting observation is that as the solid boosters heated up from reentry the nozzles glowed rather then the whole booster.


Echo 2 wouldn't try to fix the parachute problem, instead I fitted it with science instruments to take orbital readings and transmit them. I wasn't sure how much power the GravMax would need so I packed extra batteries. With the extra weight Echo 2 didn't fly as high - in fact it just barely touched the edge of space where I quickly stored all the readings and then began transmitting them as the ship fell back down.


This lets me unlock Basic Flight Control and the control fins. I have 24 science left but everything now costs 45 science. With the technology I have I can probably put a short term satellite into orbit and take more gravity readings.


Share this post

Link to post
Share on other sites

Hotel 1-3

Expanding on the last Golf design is Hotel. After making that report I realized that getting into orbit would be a lot harder then I thought - not only would I lack decouplers to efficiently stage (not too big of a problem for basic orbit) but even with the fins I wouldn't be able to change orientation once I'd gotten too far above the lower atmosphere because there wouldn't be enough air to use the control surfaces.

I thought I'd try to get something resembling an orbit by making a sharp gravity turn. I'd try to maximum my potential science by flying toward the north pole and would carry enough battery power for 4 gravity transmissions (my records from Golf 3 give me a good idea how much charge I need and showed that the Gravmax is the only instrument so far that can take biome specific readings) and about 40 minutes of flight. That turned out to be a bit too ambitious, the fins where unable to counteract the other forces and when I started the gravity turn it just kept turning until I was pointed down.


So instead I built a modified version of Golf 2 designed for basic suborbital flights with enough battery power to transmit gravity readings from over 2 biomes. The additional batteries would add weight. So would the fins and the fact that I'd be flying at an angle instead of straight up. Just barely touching space for 10 seconds wouldn't be enough to get readings on 2 biomes so I added an additional pair of solid boosters, with staging to run each pair seperately.

The first flight of the revised design, Hotel 2, was turned west but only slightly. Since I wasn't even trying to get into orbit I just needed to add some horizontal velocity so that I'd pass over the highlands and mountains near the KSP. Without SAS it required a lot of hands on flying but things worked out well - I was able to scan and transmit readings on both the highlands and the mountain range west of KSP before coming down on the west coast.


As it entered the atmosphere the battery expired which apparently damaged the probe, though the explosive damage came later as it picked up heat on reentry. A massive chain of explosions started which according to the log where all of the batteries breaking from the g-force.


Hotel 3 was an identical craft but sent south east in the hopes of skimming along the coast so I could get a shore and water reading. It was successful at that and during reentry it also suffered g-force related destruction of batteries but not all of them this time (well at least until it smacked into the water).


These two flights provide enough science to unlock 2 more items. I choose to unlock Flight Control, which gives me a small RCS tank and RCS thrusters which I'll need to make proper orbit, and Science Tech which gives me another experiment (Goo Container) a better battery (which looks just like the radial xenon container) and a cockpit that can operate in the upper atmosphere. It's stats show it has 100 units of some kind of life support. I'll need to make a flight to figure out just what that means. I can also see looking at the techs now available to be unlocked that the Double-C is there - so unless it has been scaled in size it will look exactly like the battery I have.


Share this post

Link to post
Share on other sites

India 1 - 3

I have goo containers and I have a new capsule that said it is partially pressurized but won't work in a vacuum. I wanted to get goo results from the upper and lower atmosphere, get a crew report from the upper atmosphere and get some data on how life support worked. The ship is deliberately similar to Echo 3 since that ship was able to land and I don't see any other way of mounting parachutes since the new pod doesn't have a nose mounting point. I launch and slowly climb up to 17km where the engines are cut. The crew and goo reports are stored and the ship keeps drifting up reaching a maximum altitude of 31km. Unfortunately at 30km there is an explosive decompression - I had not expected it to encounter problems until I reached orbit. The decompression leaves me without a command pod or a kerbal. Unfortunately it took the life of Luke Kerman who I had been trying to save for a later mission but got in this pod because I wasn't paying attention.


I tried another flight with Fredson Kerman but lost control after 2km. Attempting a safe landing ripped apart the ship.


I scaled down my mission goals and went back to unmanned flight. India 3 used a variant of a proven probe design to lift 2 goo containers up to 30km. This was the first time I tried to soft land this probe and while it was left in pieces the goo containers where both recoverable.


It is getting dark out so I'll be waiting until the sunrise before launching another mission.

Share this post

Link to post
Share on other sites

Juliet 1

With the goo objective completed I turned back to trying a high atmosphere manned flight. The small solid boosters seem to be the only reliable rockets I have, liquid fuel engines (at least the T15) are very finicky in BTSM and the fact that you can only use a large tank only makes it harder. I think this is a very interesting change; in stock KSP I rarely use solid boosters because they have no control but in real life they are simplier and more reliable then liquid rockets. In BTSM that is true too and it really adds something to the early gameplay.

Lemgur Kerman will take up the next attempt. The staging is the same as the probe design however after the 2 outer boosters fire I wait until my vertical speed is almost back to 0 m/s before engaging the center engine. This turns out to cut it very close - the ship halts the ascent and begins to turn over at 29.1km, less then 1km from the decompression point.


I was aiming for a water landing (using the fins to provide some guidance during the ascent) and succeeded. The parachutes worked and the capsule was going slow enough that it survived, bringing Lemgur and his crew report back safely.


I have a total of 99 science now, so I could unlock up to 2 of the current tier of items or 1 of the next. There is a mercury style space capsule within reach but BTSM, at least at this stage, really encourages you to unlock the lower stuff first. Unlike stock where the first 4 techs are enough for a complete rocket and lander here I don't even have decouplers yet. I decide to unlock General Construction to get those decouplers but don't spend the remainder on Advanced Rocketry (which would get me a smaller fuel tank and an LV-909 like engine). For now I think I'll try to save for the capsule.


Edited by Dave Kerbin
  • Like 1

Share this post

Link to post
Share on other sites

Another fine addition to your series of career mode threads. I'll be watching out for more of this one.

Share this post

Link to post
Share on other sites

I want to take a sidenote here to talk about my impressions of Better Than Starting Manned so far.

Overall I like this mod. It adds a lot of challenge, not in the form of extra busy work or in building huge ships but in basic design. If you play stock and miss a lot of the early challenge/discovery that came with playing and discovering things by trial and error then this is a good one. The nerfing of reaction wheels (I haven't even unlocked the first one which is available for 90 science but looks like it provides just 0.3 torque!) makes designing ships for flight much more interesting. The tech tree as a whole really extends the early flight stage - every early tech is valuable and gets you one step closer to a ship that actually gets into orbit. Science is much more restrictive - you get more of the science instruments up front (I can see the Double-C on the 90pt tier) but the surface of Kerbin is already explored and the GravMax is more balanced (it returns 25% more science but can only be used in low orbit - Kilo which I just flew confirmed that).

Another thing that makes designing more interesting is the way parts fit together. For my RCS I only have one type of tank right now, a tiny stack tank. That creates issues on where it can be placed without comprimising the structure of the ship. And then there are no radial parachutes near the start (the next parachute I can see is on the 90pt tier and its the XL parachute), which Juliet showed present other challenges. In Kilo I also ran into issues with the placement of solid boosters since I had nothing to space them out and prevent overheating. Overheating itself is interesting - I actually designed Kilo with my traditional spreadsheet method and only after flying it did I realize my thrust calculations for the liquid engines couldn't work because at 100% throttle they would explode!

Visually there are some cool things too. Because reaction wheels don't exist until later my first orbital probe (Kilo, report coming soon) would slowly spin as it drifted in orbit. Unfortunately time warping removes any rotational velocity but until then the effect really gives the environment a better 'feel'. The slow uncontrolled spin gives my probe the proper 'feel' of weightless that is missing when it is just sitting there motionless with the camera locked firmly on.

The only real negative I have so far is that I'm not a fan of reusing some of the games models for completely different types of equipment. The T15 engine, which is a scaled version of the T30 (the flavor text even mentions the name on the side being in error), is fine. It's the batteries that are a bit off. Maybe it's because the mod author doesn't like the look of the stock batteries which I can sort of agree on (they are a bit too cartoony) but to maintain some of the feel of stock it shouldn't use those art assets for something completely different, especially when it looks like they will then be used for their original purpose too (so I have a battery and a double-c that look the same). The mod itself is very small (less then 1MB) and all code. Maybe someone with art skills could partner up to create some original assets for batteries and anything else that needs a unique model.

Share this post

Link to post
Share on other sites

Kilo 1-3

I intended Kilo to be a pair of missions using the same spacecraft which would use my new decouplers to make a reasonable journey into orbit. One would orbit the equater and take a gravity scan of the desert and if it could find it the badlands (I've never been able to get an orbital scan of the badlands). The second would take a polar orbit and scan the tundra and ice caps. I calculated out the batteries I would need (the new XL batteries have a better charge:mass ratio) for the two transmissions and enough operations time to make at least one complete orbit after launch.

This was the first mission in the new mode that I planned out by spreadsheet. I've started to make my own reference list of the unique mass and other attributes (like heat tolerance) of the parts in BTSM. One thing that stands out is just how heavy things get. This is an extremely basic probe with a single instrument (GravMax) and enough power for one orbit. Without fuel or engines it weighs 2.45 tons. My calculations where conservative on the ISP I'd be getting for each stage but for the launch I did have one specific concern. The bottom of the rocket consists of 4 solid boosters around a center booster, not unlike my probes. I've calculated the thrust and even with the radial boosters empty the center can't lift the rocket on its own. That means I'll need to run 2 radial and the center at the same time to keep enough thrust and I was worried about them overheating each other. Without any item like girders to space them out I would just have to try. Unfortunately overheat is exactly what they did, and they where almost done burning too. The explosion was uneven (only one blew up) and that flipped the rocket far off course into an unrecoverable spin.


Kilo 2 was modified to use a larger BACC solid booster in the center which also added additional control surfaces. The staging was altered to fire all 4 of the smaller SBs followed by the center booster. Take off on the 4 SBs seemed ok but once I switched to the center engine I was far short on thrust. I dropped from 210 m/s down to 120 m/s before the load was light enough to start gaining speed. By the time I started picking up speed again I had burned more then half the solid fuel and I only made to it 180 m/s at 11 km when I staged and engaged the liquid engine. Here I encountered another oversight, my thrust calculations normally assume 100% from liquid engines, but the T15 can't run at 100% without exploding so I had to throttle down.


I pushed on but things didn't really seem to be going well until I staged to the second liquid engine. With less mass and at 29 km in altitude when it started up there was little to stop it from putting on a lot of speed. Clear of the bulk of the atmosphere the control surfaces aren't useful anymore so they where put on the lower stage. It requires a lot of piloting input to keep steady but it makes it into orbit with fuel to spare. From here I began an orbit of the planet, searching mainly for the badlands. I was unable to find it, though I found two places where it briefly registered as tundra (too short to grab a reading). I took readings over the desert and with the extra battery power to allow another couple of orbits (no power used for badlands transmission) I used some of the left over fuel to boost my AP into high orbit so I could see for myself if the GravMax worked there. The result was negative but it was a useful piece of information.


Finally I lowered my PE into the atmosphere which would both dispose of the probe and let me observe a reentry from orbit. Kilo 2 came apart at roughly 31 km, it's systems burning up in rapid succession until there was nothing left.

For Kilo 2 I wanted to make a slight adjustment. Knowing that I'd be able to reach high orbit briefly I packed a pair of weight balanced 2Hots to see if I could take a temperature reading. This doesn't work in stock (2Hot only works in low orbit or lower), but then the GravMax works different here so I should test to be sure. I launched and turned toward a polar orbit. I didn't get the gravity turn as well as I did the first time - that was mostly luck - and the extra weight cut down on my delta-v too. However since I knew I'd have limited power to make 3 readings (2 GravMax and 1 2Hot) I had planned from the start to raise my initial AP all the way into high orbit so I could get all the readings in less time then it took to make a complete orbit. I ran out of fuel just before the orbital burn was complete but some RCS was enough to push my AP up another 10km, for a final orbit of 74 km x 255 km with the PE above and a bit north of KSC. I was able to take readings of the ice caps and tundra as I passed over the north pole.


In high orbit I was pleasantly surprised to find that the 2Hot worked, giving me another 8 science. That information should be useful in the future. With half a tank of RCS I lowered my PE to dispose of the probe. I use the science to unlock Advanced Rocketry to give me the LV-909 like engine and smaller fuel tank and Space Exploration to give me the mercury style pod. From here I can see that Fuel Systems is interesting - you get the big orange tank along with all of the large to small adapters. It would seem the intent is that rather then have a lot of radial attachment at the start the tech tree is forcing vertical designs. The jumbo and the adapters means you can build a rocket with that big tank and 4 engines under it.


Share this post

Link to post
Share on other sites

Lima 1-3

I now have the parts that I should, in theory, be able to put a kerbal in orbit. My orbital capsule consists of the reentry portion (the Mk1 capsule and a parachute) along with a service module composed of the smaller fuel tank I now have, the smaller LV405 engine (which is basically a slightly heavier, slightly less efficient LV909) 3 batteries and RCS thrusters. I calculated the battery life for a minimum of 60 minutes of operation, though actual life support would be less then that I wanted a safety margin. The pod itself has 10 units of monopropellent just like it does in stock .23. However the pod is a lot heavier then stock - 2.99 tons with the monopropellent. I'm guessing part of that is the built in heatshield and the life support stuff. Either way it should make an interesting balance against the lander can which I assume will be much lighter but obviously be totally inappropriate for atmospheric reentry.

I need the limited monopropellent in the pod for when it is in orbit so I've disabled it in the VAB and will reenable it when it stages (too bad you can't drop action group items into the staging list). For ascent once the control surfaces are dropped there are additional tanks of monopropellent on the 2nd booster stage. I've also disabled the pods batteries - those will be saved until just before seperation so that the batteries on the service module are used and the pod battery stays full for the descent.

Lima 1 uses 3-way symmetry and has 2 booster stages. I'm back to trying liquid rockets but Lima 1 doesn't really perform - it just doesn't have enough thrust once the center engine cuts out and ends up bleeding too much delta-v on the way up. The AP only gets up to about 65 km and despite an effort in the orbital module to boost into a sub-orbital (but actually in space) flight it doesn't work. Fortunately the reentry system does work correctly and Nedvan Kerman returns safely, breaking my streak of dead kerbals.


Lima 2 uses the same orbital module but switches to larger engines - 3x T15's on the upper stage, 5x on the lower using all T800 tanks. Merdun Kerman takes the ship up this time. There is spin on the ascent but Lima 3 showed that it was down to piloting rather then a flaw in the craft. There is enough thrust to run the engines at 80% - this seems to be the sweet spot for the TN15 so I'll use it in my thrust calculations. I'm not quite sure how long I need to burn for the circulization, I end up starting the burn too late and my PE needs to be corrected to 70 km.




After orbiting a burn is made to bring Merdun back. As the ship leaves orbit the command pods battery is activated and the service module is ejected. The service module is pushed into a slightly faster descent ahead of the command pod. This provides a valuable reference point since I can observe when it begins to break up and compare that to how the heat shield is protecting the command pod and parachute. You can see in the animation how parts begin to smoke and then explode in sequence, eventually the main structure breaks up leaving multiple chunks which burn up until there is nothing left of the service module.


Lima 3 wasn't originally scheduled. If all had gone well Lima would have been a conservative single mission to put a kerbal in low orbit (I have future plans about testing goo container reentry but I wanted to get this done safely first). The failure of Lima 1 to fully meet its goals (in particular no crew report from low orbit) required Lima 2. However with the success of Lima 2, which still had fuel left, I prepared and launched Lema 3 which was an identical ship to be flown into high orbit. This would get a high orbit crew report and provide another test of reentry - I need to make sure I have it working like clockwork if I want to make manned missions beyond LKO.

Jorster Kerman is flying this one and it turns into a rather routine flight thanks to the incremental improvements in flight control and design I've made. After making a high orbit pass he comes back in for a landing, setting a PE of 20 km to enter the atmosphere. Life support is more then half depleted by the journey after barely completing an enlarged orbit. More life support will be needed to go beyond Kerbin. And the Mk1 doesn't float very well, it would be best if kerbals don't open the hatch until they are recovered.




Share this post

Link to post
Share on other sites

Mike 1

Mike was planned as two missions. I want to return goo containers from orbit (they are worth some good science). However to do this I need to protect them from reentry. My idea was if I attached them to the side of the Mk1 pod (the way most of us did when they first appeared in .22) they might be protected the way the parachute is. I had even considered this as a part of Lima but with all the kerbal deaths I decided to focus on just one goal at a time. For this mission I still didn't want to risk a kerbal in the event that the goo containers might compromise the pod and I didn't want to design a whole ship. So I planned two missions both of which would be flown with a modified version of the Lima 2/3 space craft.

The first mission would fly with 2 goo containers attached to the pod. This would add weight but that wouldn't be too important because we wouldn't try to get into proper orbit, just ascend to 250 km and then fall back down. In order to avoid risking a kerbal this dry run would be setup to 'fail' from the start - the parachute would be a replaced by a Stayputnick so that the whole flight could be made remotely. The final 3000m would be a predetermined failure, but everything before that would prove if the concept worked.

Things go well at first. The spacecraft has enough thrust and delta-v to insert the modified capsule into a 251 km suborbital path.


Coming back down poses a problem though. With the service module nearby (the nearly straight up path means they don't seperate very much) we can see the moment that the reentry forces hit a critical point. At which point both goo containers are also destroyed. The rest of the pod comes through, but obviously the goo containers are too far out to be protected by the heat shield. There is no point in running a Mike 2 manned mission.



Since I still need more science I'm going to start planning a Mun flyby. With the weight of batteries it won't be light, which makes it feel a lot more like the early space program where everything wasn't just microchips and you needed big tubes and powercells to run a probe.

Share this post

Link to post
Share on other sites

Question: Have you tried grabbing the science from any of your instruments? If you can do that then you can run a manned Mike Mission and grab the science from the Goo before you reenter.

Share this post

Link to post
Share on other sites
Question: Have you tried grabbing the science from any of your instruments? If you can do that then you can run a manned Mike Mission and grab the science from the Goo before you reenter.

BTSM modifies how science is done. Every experiment transmits at either 100% or 0%. So for the 2Hot and GravMax I can either return the instrument or transmit for 100% of the science on the first run (there is no additional science to be gained by repeats). For the Goo Containers (and I assume the Science Jr) you must return it to get the science. I don't know whether you can use a kerbal to bring the experiment back into the pod the way you can in stock .23. At the moment I don't have the technology for EVAs (no space suits) and I have a feeling BTSM doesn't allow that feature though once I can do an EVA I'll be trying (it doesn't look like EVAs are coming soon though, they must be at least in the 160pt tier). To bring the Goo Containers back to the ground I'll need a bigger heatshield. I can see one available on the 90pt tier, though I haven't figured out which item I will unlock first at that stage. Honestly without radial decouplers (or much of any structural part to help) I think I might need to tech tier that gives me the orange tank and the mounts so that I can get a descent payload into orbit. Until I have better power technology (solar panels are also too far off to see yet) even my probes are really heavy if I want to get anywhere.

Here is the goo container from Mike 1. As you can see returning it is the only option.


Share this post

Link to post
Share on other sites

Well then, I play with DRE but not BTSM, but rotating the pod as it reenters helps. You could also try setting your periapsis higher (About 36k) and see if that helps at all.

Share this post

Link to post
Share on other sites

The pod itself is fine, it's the bits sticking out from the side and beyond the diameter of the shield (goo containers) that got fried on reentry. Because of the entry profile the heatshield didn't even wear down as much as the previous runs (Lima burned off about 65% of the shield, Mike lost less then 40%).

One other thing I could try is changing the position of the goo containers - maybe if I stack them horizontally I can squeeze them close enough that they don't peek out over the shield and get melted by the super hot plasma stream.


Share this post

Link to post
Share on other sites
The pod itself is fine, it's the bits sticking out from the side and beyond the diameter of the shield (goo containers) that got fried on reentry. Because of the entry profile the heatshield didn't even wear down as much as the previous runs (Lima burned off about 65% of the shield, Mike lost less then 40%).

One other thing I could try is changing the position of the goo containers - maybe if I stack them horizontally I can squeeze them close enough that they don't peek out over the shield and get melted by the super hot plasma stream.


That might work.

Share this post

Link to post
Share on other sites

Mike 2-4

I've gone back to see if the Mike concept can be made to work.

Mike 2 was another unmanned run but with the containers placed horizontally and as tightly as possible. It still doesn't look like they are completely covered by the shield. Preparing for reentry I titled the pod sideways a bit so the service module wouldn't have any chance to collide if it experienced more drag and slowed down faster. This resulted in the command pod stuck in a tilted position which may have provided some additional protection, I'm not sure. Either way the goo containers survived so it is go for a manned attempt.


Hanemone Kerman is back to fly this attempt. He takes Mike 3 up to 252 km and then comes back down. However without the weight of the Stayputnick the pod can't maintain attitude and orients back to center. Both goo containers are destroyed but the capsule is fine and Hanemone lands safely.


Since no one was killed I decide to try one more time. Merdun pilots Mike 4 which only goes up to 72 km, I don't even use all the fuel in the 2nd stage booster. The lower velocity seems to help. Despite the pod still correcting its orientation the goo containers don't explode. I can confirm that the lower velocity was the reason because the service module also survived reentry.


With only samples from low orbit (I exposed both in case one was destroyed) I gain 50 science, enough to unlock one more item. If I could get high orbit samples I would have enough science for another item. Out of the available technologies some don't seem useful yet - I see technology for landings and faster transmissions which at this point are secondary to actually getting somewhere. I see a slightly better engine (the normal T30) but I don't think that would be enough. I see heat shield technology but that would have limited use right now, I need a lot more then just returning goo from high orbit. Then there is docking which could be useful - I might be able to assemble something in orbit. But what I think I really need now are Fuel Systems, which give me that orange tank and the adapters for attaching multiple engines to it, and Advanced Flight Control. This has some useful parts - a dedicated reaction wheel, SAS system and small RCS tank but the real reason I'm taking this first before fuel systems is the new QBE probe core. This probe core weighs less (.25 tons) and much more importantly it uses half the power. Because batteries are such a big part of reaching the Mun and because they weigh so much in BTSM reducing the power requirements is the single best way of reducing payload weight and thus extending delta-v. I think with this probe core I can reach the Mun.


Share this post

Link to post
Share on other sites

November 1-2

The goal of November is to reach the Mun and transmit some basic readings. This won't be an attempt to orbit the Mun, there just isn't enough battery power for that. Remembering older missions I think I can get to the Mun in 6 hours though that will still be tight given how many batteries I can carry without exceeding my payload capacity.

November 1 uses the same launch platform I've been using, only it replaces the 3 ton pod with a much lighter probe core. It then doubles the number of batteries and finally the 1st booster stage needs to expand from 4 to 6 radial engines. I've fitted a 2Hot to take readings. There is a lot of spin during launch, I haven't put aside any weight for an SAS control system so its manual stabilization the whole way. With more delta-v in the 1st stage the 2nd stage can be used for part of the circulization burn. After that the orbital module plots a course to the Mun. This is a collision course but that's fine, we'll only have the power and opportunity for 2 temperature readings anyway and this should neatly dispose of the probe when it is done.

Reaching the Mun there is a minor letdown. In stock .23 the Mun's orbit has a multiplier of 3x compared to 1x in Kerbin orbit. So the same reading will return 3 times the science. In BTSM that doesn't seem to be the case. The Mun is worth 1x so I only get 8 science for the high orbit reading and 8 science the low orbit reading before it crashes. Power wise I still had over 700 em when I 'landed' so I may be able to get more science (I really need it so I can unlock something else) if I send a GravMax instrument.


November 2 does just that, fitting a GravMax instead of a 2Hot. Due to weight balancing I am able to slightly reduce the overall mass of the ship. This time I won't collide with the Mun, I need to be in low orbit to take a reading and the GravMax takes a while to transmit so I want to be sure it won't crash. Reaching the Mun a course correction is used to bring the probe in close. Readings are taken of the Mun's Midlands and with enough power left a second reading is taken of the Highlands. The two readings provide 50 science in total, the same 25 science/reading as I got in LKO.


With the probe having done it's work and with 50 minutes of life is left to drift (there is not enough fuel to make a large enough correction to send it into the Mun). It will be recieve an assist from the Mun's gravity that will fling it out into orbit around the Sun. I'll see about marking it as debris.


That leaves a question of what to do with my science. I have enough to unlock one thing. It's obvious that I at least need to be able to get into orbit around the Mun with some good battery power to take GravMax readings if I want to proceed further in the tech tree. It's also becoming obvious that I'm not going to find a ton of science on the Mun, at least not with a single landing like I'm used to. I'm going to need to explore the whole surface just to advance. Of the items I can unlock the heatshield and antenna are still nice to haves but won't really change things much. The landing equipment, which includes the Double-C, could be interesting but I have no idea how much science the instrument itself provides and what my other instruments (2Hot) would provide if I made a landing. I also don't know how much power it uses to transmit. I've rerun the numbers and the orange tank doesn't open things up as much as I need them to, it really wouldn't be better then my current launch vehicle. The T30 engine could be useful but that would depend a lot on how hard it can be run. If it still has the same overheating threshhold as the T15 then I won't have gained enough.

That leaves me with structural technology which includes docking ports, size adapters and struts. I have an idea of using the docking port to let me place a support module into orbit - a partially used fuel tank with lots of batteries. A Munar probe would then launch and link up with the support module before making it's way to the Mun. In the worst case I'll need those struts if I'm force to make even bigger launchers, since without any radial decoupling mechanism I need ever bigger stages to provide enough thrust.

Share this post

Link to post
Share on other sites

Oscar 2

First you might be asking where is Oscar 1. Oscar 1 never reached the pad but progressed far enough that I already had a craft file for it (2 actually as will be explained). With the name already used I went to the next available number rather then overwrite it. Oscar 1 used a design almost identical to November to enter orbit around the Mun with enough battery power for multiple GravMax transmissions (that's a lot of power). To do that the November capsule was stripped down to just 2 batteries and a docking port was added on top to be used with a support module. The support module was basically a light frame rig with a docking port and a lot of batteries, over 4 tons worth (which sounds like a lot but is barely enough to support a few Mun orbits and some GravMax transmissoin).

The mission plan would have the first probe launch carrying the support module (all the batteries on the support module would be turned off). The fuel normally used to reach the Mun would instead be used just to get the module into orbit. The second probe, much lighter then the first, would launch on the first orbit to quickly catch up and dock with the support module as it entered its second (it the first probe ran out of power it wasn't fatal but would mean docking with a dead mass). The second probe would take possession of the support module and steal any fuel and monopropellent it could from the first probe. With a hopefully full tank it would then fly to the Mun and enter orbit with enough power to transmit multiple readings from the GravMax.


There where two issues with this plan. Docking itself wasn't an issue but quickly setting up a renderous and just doing two launches for one throw away probe seemed like extra work. The bigger issue was that I had still hadn't fully worked out the exact delta-v and thrust values with all the swapping of parts and fuel going on. It was very possible that the first probe could fail to get into orbit, or the second probe wouldn't have as much left over fuel as I thought, or it might not be able to get into orbit around the Mun even with a full tank once the rig was attached.

My backup plan for choosing the node I did on the tech tree was that if docking ports didn't work out I could instead use the struts to build a monster launcher and get something bigger into space. And that's exactly what I did. I designed a capsule to go from LKO to LMO on a full tank, with enough power that it could send 8 GravMax transmissions and do about 4 orbits, and then built a launcher to get it into orbit as a payload. Struts allowed me to build the first stage outward (a requirement since I needed more thrust and needed more attachment points then just a single decoupler, all without the ship flexing and bending).

Oscar 2 fully utilized thrust tweaking calculations (while SBs and fuel tanks can't be tweaked in BTSM the liquid rockets can) so that I could run the ship at 100% throttle and not have to micromanage drag or heat. I also installed an SAS system in the launcher (for weight savings the Mun probe itself still relies on manual stabilization) to further reduce the workload. Ideally I can reuse the launcher for several missions before I need a bigger one or have enough technology to redesign it. I was surprised to find out that the small RCS tank actually carries a lot, 250 units compared to the 50 carried by the tiny one (in stock the small tank carries 100 units). This meant that I had more then enough monopropellent for the launch and could leave it on the entire time to aid the SAS system.

The first stage consists of 12 engines, 4 clusters of 3 engines each which are attached by individual decoupler to one of the 4 radial engines of the 2nd stage. The center of the first stage is empty space with the structure supported by struts. The second stage is far more familiar, 4 engines around a 5th center engine. When it is activated the first stage splits into pieces and falls away. The gravity turn is timed to start immediately afterward.


The 3rd booster stage consists of a final T15 engine and T800 fuel tank along with the SAS and RCS systems used by the entire launcher. This stage has a little more then 1000 m/s and is used for the circulization burn. Any left over fuel can be used to assist with the Mun injection burn (the SAS system also cancels out any rotation before that burn starts, reducing the need for any corrections).


My course for the Mun isn't as fast as before. I'm trading some battery life for fuel to reduce the cost of my capture burn. Capturing uses up almost all of the remaining fuel but leaves me in low orbit.


Oscar 2 begins scanning with the GravMax. The previous trip in November 2 identified the Midlands and Highlands which make up most of the Mun's surface. I quickly pass over Highland craters but these areas are incredibly tiny, the scanner is over them for less then a second. Midland craters are easier to get a fix on. As the probe passes to the night side it finds the Northwest Crater and the Farside Crater before coming on a larger set of Highland Craters that can be scanned. The Twin Craters are scanned next after which all remaining fuel and RCS is used in an attempt to change the orbital inclination (there is only about 60 m/s to work with) for the next pass around the Mun. Power is running out and while there was power planned for 8 scans it did not take into account the longer trip to the Mun or the number of orbits needed. Ultimately it's not important, with the small plane change only two new features can be found, the Northern Basin on the dark side and some Canyons near the Twin Craters. With 7 scans complete the power levels are too low for another complete scan even if something could be found. There is no fuel or RCS so the probe can only float as debris for another 62 minutes (around 2 more orbits) before it dies.


With 7 scans I gain 175 science. Combined with some banked science I have enough to unlock 2 more 90pt nodes though I haven't decided which yet. I'm tempted to unlock landing and find out how much power is required for the Double-C and what science can be returned from the Mun's surface. By cutting down on batteries I could free up enough weight to add fuel for a landing. Mounting 2 batteries and the instruments directly to the probe core (30 m/s impact rating) I wouldn't even need a smooth landing. Another mission would be to stretch Oscar's fuel enough to make a low orbit flyby of Minmus (maybe take off 2 batteries). There would only be time and power for 1 or 2 transmissions (like the November 2 flyby) but it would give me data on what scientific value Minmus has. Ultimately I will also need to send one or two more Oscar missions to make GravMax scans of the Mun's other regions, there should be something like 400 science left to be harvested there.

Share this post

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now