Starlionblue

Most impressive.

Looking in Task Manager, the first option (non-32 bit) is called "KSP_x64" so...

Only noticed it was a necrothread after I responded to it. Oops!

Indeed, but this only really works with very maneuverable aircraft. Since you can't hold altitude (without rudder application) it's not very practical for larger aircraft with a slower roll rate.

In heavy jets we don't touch the rudder pedals at all except on the ground, while decrabbing on touchdown and in an engine-out situation. We only use pitch and roll inputs to steer the aircraft. You roll into a turn and apply backpressure on the stick/yoke to maintain the nose level. Backpressure is needed because load factor on the wings increases in a turn. Importantly, this doesn't mean the rudder doesn't move. We just don't make the inputs ourselves. The yaw damper system moves the rudder to ensures turns are coordinated, in other words we're not "skidding" in a turn but the longitudinal axis of the aircraft follows the turn neatly. Same as you (should) do in a lighter aircraft with your feet on the rudder pedals. Why the yaw damper? Swept wing planes typically have a tendency to enter a coupled roll-yaw motion known as Dutch Roll, which is uncomfortable and potentially dangerous. Apart from turn coordination, the yaw damper counters Dutch Roll tendencies. You can easily see Dutch Roll in KSP planes if you don't have enough stability in yaw (not enough vertical fin area basically). The plane will rock side to side while rolling with the nose drawing a figure of eight. I'd love to see a yaw damper mod for KSP, because frankly any plane with that kind of geometry performance should have one.

I get the impression that MechJeb struggles with orbital transfers with large vehicles, especially if they're not very stiff. If the vehicle starts to wobble even a bit during a Kerbin departure burn, this can lead to major errors in the transfer orbit over interplanetary distances. Another problem is long departure burns which takes up a large slice of the orbit. The "perfect" burn would be instantaneous at the node, and the longer the burn the more thrust is applied at suboptimal times away from the node. In most cases given the timescales and distances involved it is no big deal, but if a burn take, say 10 minutes of a 70 minute orbit, MechJeb calculations can be off by quite a bit. The solution is to split the departure burn up into shorter burns over multiple orbits, gradually making the orbit more elliptical until the final departure with what are sometimes called "periapsis kicks".. Incidentally, this also saves fuel.

Yay! Thanks! For comparison then , here's the 0.9 Eve mission and below it the 1.05 Eve mission. You can see how much more massive the Eve lander needed to be. More than twice the weight, so even without the heat shielding needed in 1.05, it was a nightmare. The new aerodynamics model also means that "wide and flat" vehicles with little streamlining aren't a good idea in atmospheres, especially a very thick atmosphere like Eve's. My 0.9 lander would have burned up on ascent from Eve's surface if I tried it in 1.05. And I think it would also have been unstable at higher speeds, leading to tumbling. There's a reason the 1.05 middle stage has rudders/fins. In hindsight, my 1.05 vehicle could have been quite a bit smaller, as it ended up back in Eve orbit with almost 4000 delta-V left. Eve mission 0.9 Eve mission 1.05

The nightmares I had in 0.9 with the Eve thing. Took me over a month to build mine in 0.9. 5600 tons on the pad at the KSP and 650 tons on landing on Eve. https://imgur.com/a/5vIFe#0 (How do I embed IMGUR albums?)

It is both easier and harder than in 0.9. On the one hand it has become easier because the delta-V requirement to get to Eve orbit is far lower than before. Something like 8500 from sea level as opposed to the 13000 in 0.9. The lander can be made with half the parts, if that. On the other hand it has become harder because of heating, both on entry and on ascent. All in all I found it much easier once I'd figured out re-entry sans incineration. For ascent, the MechJeb Q limit feature is a godsend.

Extremely Vexing Exoexplorer? I may have been frustrated with this challenge at some point. My starting point save is called "Prelude to Frustration".

The "problem" I have now is that since I had all that delta-V left I'm tempted to try a sea-level landing. I'm just worried wife will leave me and stuff if I spend any more time obsessing over KSP. And then there's the whole "holding down a job" thing...

Oops...

Whoooo! I did it. Finally did it! My lander had around 10500 delta-V. After much finicking with re-entry I managed to set her down at 3500 altitude. Eve return mission 1.05 (How do I embed Imgur albums?) Stable Eve orbit was achieved with.... over 3800 delta-v left?!? I may have overbuilt. I do get the feeling that while 13000 delta-V from Eve sealevel is a good ballpark, you can make huge efficiency gains with aerodynamic and ascent profile optimization. For one thing using the Mk1 command module and a nose cone is way better than using the Mk1 lander can and a nose cone despite the increase in weight. Also, the can makes control difficult as it tends to drag the nose to one side. This easily leads to tumbling. Some notes: Yes, I know my Kerbin booster is sheer brute force and could have been done much more elegantly. However it did keep the parts count and complication down. Heat shields are tricky, and so is keeping the lander behind the heat shield. I had to add a bunch or RCS and also fins at the top for a weathervane effect. I managed entry into the Evemosphere with my main engine heated to 92% of its max. When entering the Evemosphere a shallow entry angle is critical to limit heat buildup. While asparagus is more efficient, for the lander I chose a rather traditional three stage design with only a little asparagus for the first stage. The added complication of asparagus was making things way overcomplex in the first 10 iterations. One Mammoth engine and the biggest Kerbodyne tank go a long way. Unexpected complication: Eve ascent. I managed to blow up dozens of times. Two factors to consider: When to start the "gravity turn". Too early and you will eventually heat up the command pod and nose cone to destruction as you try to accelerate in the thickest part of the Evemosphere. Too late and you're wasting fuel. Around 25000 meters seemed like a reasonable number. Dynamic pressure. Too high and you're wasting fuel. Too low and you're not climbing fast enough. After some experimenting I went with 40000pa. I get the feeling you want it high in the beginning to "punch through" the thicker parts of the atmosphere as fast as possible at the expense of some higher drag. By starting my "gravity turn" around 25km, when I really started to increase the horizontal component to orbital speed I was (just) above the altitude where heating became a showstopper. (On return, I missed the KSC by about 50km but I'll take it.)

Now that I finally figured out how to stitch heatshields together, I've finally been making some progress... Thank goodness for HyperEdit so I can test stuff easily. Sure!

I am pretty sure (ha!) I can do it in two. One monstrous vehicle for the Eve transit+lander+ascent vehicle. Another launch for a vehicle to pick up the Kerbonaut in Low Eve Orbit. I've pretty much figured out the "delta-V bits". The problem I have is that the vehicle keep burning up on Eve atmospheric entry. Need to do some more testing on radially mounting heatshields. How do you do that anyway?

This challenge is driving me nuts... I keep overbuilding. The parts count and weight skyrocket and then I burn up on Eve entry. If I was a less obsessive individual I'd give up...

Sorry abou the necrothread. I'm having a similar weird issue with uneven tank drainage. Shown in the pic is my as yet unfinished Eve lander. It's a "layer cake" style asparagus with engines in all three layers firing at the same time (except center engines of course). Basically the asparagus starts by draining the large tanks at the bottom in pairs, then goes into the bottom ring and drains pairs, then joins in the bottom inner tank, then splits in two again to go up one level to the outer middle boosters, goes around the ring, joins in the middle, then does the same for the top level. Here's the weird bit. One of the "first" pair of tanks in the middle layer (first tanks to be used up and jettisoned in middle layer) strats draining at launch. Even more weird is that it doesn't drain quickly as if it's not getting any fuel from upstream. It drains quite slowly but still noticeably, so there is fuel from going "through" it. I have checked and double checked the fuel lines. I have rebuilt the entire stack from scratch (three times). I have tried different configurations. I have painstakingly placed the fuel lines in the exact same positions. I have tried doubling up fuel lines. I have tried a quadsparagus instead of a twinsparagus. I have yelled at the PC and invoked dark deities. I have drunk beer and I have made diagrams. None of that has worked. "Solution": Remove the top layer from the asparagus, making it a "traditional" self-contained upper stage that only fires when the final middle booster separates. The tanks in the middle layer now drain evenly. To be honest I don't lose a huge amount of delta-V from implementing the "solution", and the booster is already ridiculously efficient (I'm on track to make an Eve ascent vehicle weighing around 260 tons). It does bug me though, and I am pretty convinced that this actually is a bug. Any ideas appreciated.

Perfect. I guess we can leave the question of whether Outside Air Temperature measurement is compensated for ram rise at high speeds out of it.

I'm going to be the nitpicky pilot in this thread. Can't help myself. For the record though, I haven't even gotten close to these speeds close to the surface. The speed of sound is not an absolute. It is dependent on temperature. The formula on Earth for the local speed of sound in knots is 38.94 times the square root of the absolute temperature (temperature in degrees Kelvin). Thus in a standard atmosphere on Earth (15 degrees C at sea level), the speed of sound is 661 knots at sea level (340 m/s). In a standard atmosphere, temperature decreases by 1.98C/1000ft, and it follows that local speed of sound thus decreases with altitude. Of course in a real atmosphere the lapse rate (change of temperature with increasing altitude) is not constant, so the local speed of sound varies not only due to altitude. Then again Kerbin does not have weather so we can consider it an actual standard atmosphere. Using the standard lapse rate, at 500m the temperature is 11.75C (284.75K) so the local speed of sound is 657 knots (338 m/s). Nitpicking again, straight flight is on the same heading. Level flight is at the same altitude.

The speed of sound is not an absolute. In Earth atmosphere, it is dependent on temperature. The formula is 38.94 times the square root of the absolute temperature (temperature in degrees Kelvin). Thus in a standard atmosphere (15 degrees C at sea level), the speed of sound is 661 knots at sea level, or 340m/s. In a standard atmosphere, temperature decreases by 1.98C/1000ft, and the local speed of sound thus decreases with altitude. However in a real atmosphere the lapse rate (change of temperature with increasing altitude) is not constant, so the local speed of sound varies not only due to altitude.

Ok I think I did it now. 3 Kerbals from the KSP to Eve and back to Kerbin. One launch. No refueling or docking. Vehicle fits within the circle in the VAB. No command chairs used. And hey, I had all of 42 delta-v left over on return to Kerbin. Personally, I'd have been sweating bullets! Pics here. (I'm not allowed to post attachments yet.) Craft file available on request. Data as per OP: weight and part count of the vessel on the launchpad. 956 parts in 31 stages. 5507.1 tons. weight and part count awaiting liftoff on Eve. Around 496 parts in 16 stages, weighing around 640 tons. Numbers approximate because it depends on how much fuel is used for braking maneuver in the last few dozen meters of Eve descent. the approximate price tag of your entire mission, if at all possible. 2,718,391 game version. 0.90 mods used. MechJeb. Enhanced NavBall. Kerbal Alarm Clock. tell me how you found your landing site. "I tried until I got lucky" is perfectly alright, but inquiring minds want to know. Got lucky the first time. Highlands. At night but still fine. On earlier attempts I made small adjustment burns to change my Eve periapsis. if there's anything that your are especially proud of, be sure to point it out (provide a direct link to a picture if applicable). a) I like how I got the lower lander engines are firing all the way from the KSC by making a big hole in the middle of the Kerbin launcher. That way I'm not carrying nearly as much dead weight. I got the idea for the jettisonable parachute towers from a design I saw online, but I shaved weight off by using Sepratrons for jettison instead of the LES. c) I have an action group to shut off all but nukes for the midcourse correction towards Eve. This saves quite some fuel. please also mention the things that didn't work out so well / required a lot of saveloading / you would do different next time. This was about my 20th design, so by now I've worked out most of the kinks. Still, with closely spaced heavy separating stacks like this Sepratrons positioning always requires some fiddling. There's also a bug where they detach from some parts on firing , which means they have no effect and you have to add other Sepratrons to an adjacent part. Very annoying.

Oops darnit. Ok I'll rethink in a bit. Need to take a break from this after four weeks. I do think I am close. Just need a bit more fuel for the early Eve departure stages I think. I seem to have plenty of thrust.

I rearranged the lower stages and they now fit inside the ring. Some of the early stagings are gnarly, with bits bumping, but the vehicle consistently makes it fine to Low Kerbin Orbit. Once there, has pretty much the same delta-v left as the earlier version. The upper bits are identical. I'll go to Eve now but I think that means I made it. VAB pic of new version here.

I'm looking at it and the redesign seems relatively simple. I can squeeze in the last two rings of boosters next to the one that fits in the circle. I'll get exactly the same delta-v. Just need to fiddle with decouplers, Sepratrons and fuel lines a bit... I love this game.

AGH! Forgot to read that requirement. It is quite a bit wider unfortunately. I guess I don't qualify then. Oops. Pretty sure I can redesign. I'll get back to you. Yeah those Kerbal adult diapers are super absorbent.