post things that make you shake your head

[r4pt0r]

i got a probe up to LKO and fine tuned the orbit, managed 70.3km almost perfectly circular. my engine stage had sepratrons to deorbit and leave the probe nicely in place. decoupled/fired sepratrons. whoops, forgot about decoupler force, ended up with 70.3 x 94km orbit

back to the drawing board....

what mistakes have you made?

Edited January 22, 2014 by r4pt0r

[Madrias]

Had a safety system on one of my planes, a simple glider designed to get one back to Kerbin at just about any cost by the power of two Ant engines. Ejected the Flying Ant Safety Glider from the rest of the plane when I had a problem (unrecoverable spin caused by engine flameout, fuel tank separated from decoupler and removed half of the left hand wing) and proceeded to burn the engines to descend with a great rate of speed. Pulled out of the screaming dive at roughly 460m/s and carried myself a long way back toward KSC. As I'm hurtling toward the KSC and I've run out of fuel, my safety glider showed its true colors, proceeding to infiniglide at roughly 2000m at a speed of 60m/s. From flight trials, I knew about the infinigliding quirk, and had a plan in mind to land safely: I designed it to eject its wings and parachute in, much like a rocket does.

I leveled myself toward the runway, the control tower on my right, craft placed strategically at the four corners of the runway so I knew where to aim. At 2km the loading lag hit as I reached physics range, my Flying Ant screaming for the runway at 60 meters per second, still holding 2km altitude and travelling smoothly. Timing it just right, I deployed debris chutes, then decoupled the wings so they would fall back to Kerbin instead of hanging around and crashing my next flight. I hit space again to deploy my primary chutes.

Thunk.

A moment passed. Brief panic, though mild. Maybe it didn't register. My keyboard's a little old, sometimes space doesn't register right away if I hit the wrong side of the spacebar.

Thunk. Thunk.

Panic sets in. I'm realizing it's one of two things: my space bar is broken, or I forgot chutes.

1500 meters altitude.

Thunk thunk thunk thunk thunk.

1200 meters altitude.

My spacebar sounds like a machine gun as I'm desperately hoping that I'm just finding the wrong spots.

700 meters altitude.

I'm working the flight cluster, hoping to point the MK1 Cockpit in such a manner that I slam the tail and structural beams into the runway first, instead of the nose.

400 meters altitude.

The battery has run dry with the craft facing the runway side on. I know this is it, Jeb can't possibly survive this. I have one critical escape plan left.

200 meters altitude.

Time's up. I EVA Jeb and have him cling to the falling cockpit, planning to jump at the last second.

Roughly 100 meters altitude (I could see shadows)

I hold W with all my might, and Jeb crawls off the end of his doomed plane. There's a terrifying fireball and debris goes everywhere. I hope for the best.

Bounce.

Jeb's helmet hits the runway with full force, and he lazily ragdolls off of it and back into the air for a split moment.

Poof.

Jeb's bounce carried him, still grinning like a madman, straight into the control tower where he turned into a cloud of dust.

I went back to the drawing board and the first thing I did to the Flying Ant MKII was to rename it the Flying Ant MKIII and immediately throw two parachutes onto the design. One on the structural beam holding the tail together, the other directly behind the cockpit.

I'm up to MKIX now. Slowly working out all the bugs. Jeb's come back 4 times and I finally just retired him and his 2 brothers to my orbiting space station.

Then I accidentally put a Flying Ant through it. I really need to add some power generation to the bloody things...

[AlamoVampire]

I once was setting up a mission to either Minmus or the Mun, frankly I cannot remember, this was back in the days of .21 when I was new around here. Anyway <sadly I have done this even recently lol> I was on ascent from Kerbin, everything was fine, and I went to stage a spent lower stage. pressed space bar, and the next thing I see is my entire rocket going one way and my command pod lazily drifting along on a sub orbital path. Each time I do this <because of ignorance at first, and well, stupidity on my part now> I just gasp then shake my head as the command pod drifts for home lol.

[federicoaa]

After a lot of orbital assembly, long burn to Duna, capture, orbiting and releasing a satellite, I forgot to extend the solar panels and now it's a floating debris

[CalculusWarrior]

That lovely moment when you come back to your ship on a carefully plotted direct Laythe aerobrake (because I'm hardcore like that), think that it's actually coming in on a retrograde orbit rather than prograde, spend a couple m/s of delta v to fix it, timewarp to Laythe encounter, quicksave, try again and again to properly perform an aerobrake, succeed on the 20th try.

Phew.

Then realize you were initially correct, your orbit is now a retrograde orbit, as opposed to the prograde orbit the ship you were trying to rendezvous with is in.

Quickload, burn radially to shift your periapsis from one side of the planet to the other before hitting it, realize the distance is shrinking way to quickly because you're travelling at ~8 km/s, enter atmosphere, crash, pollute the ocean right next to your Laythe base with nuclear engines.

[SkyRender]

I've mentioned it before, but it just has to be said again: don't ever retract a ladder that you have a Kerbal currently climbing, especially not in orbit. Unless your goal is to kill all of his lateral velocity (and likely kill him shortly after), it won't end well.

[Deadpangod3]

I've mentioned it before, but it just has to be said again: don't ever retract a ladder that you have a Kerbal currently climbing, especially not in orbit. Unless your goal is to kill all of his lateral velocity (and likely kill him shortly after), it won't end well.

I might just have to test this, for science!

[nine_iron]

First launch all stages are perfect, decide to go back to VAB to tweak something on return or lander craft...

Every launch after the staging takes off my orbital insertion engine or the craft blows up. How did it work perfect the first time but not every time after that?

[Armchair Rocket Scientist]

After a lot of orbital assembly, long burn to Duna, capture, orbiting and releasing a satellite, I forgot to extend the solar panels and now it's a floating debris

I had this happen on a Huygens-type Eve probe when I accidentally pointed its (fixed) solar panels away from the sun while waiting for my landing site to come into position. Fortunately, the orbiter mothership was still close by, so I was able to bump the probe, causing it to rotate.

[Corw]

Alzheimer's

[Flixxbeatz]

Thinking that fuel lines are all attached correctly. And suddenly this happens during the climb:

[LameLefty]

I built a big, heavy nuclear transfer stage once, with a fully-crewed lander docked up front, and sent the stack off to Moho. My transfer stage had a big supply of monopropellant and a giant set of lovely solar wings. It also had a set of four large drop tanks mounted on radial separators so I could carry more propellant yet dump excess mass along the way. Towards the end of my burn, I realized the drop tanks were empty and hit the key I'd set to jettison them with - while I was still under acceleration. So of course they didn't just shoot away radially as expected - they went away and back relative to the stack, taking out both of my solar panels on the transfer stage. Fortunately my lander had smaller solar panels so I deployed them to provide power en route.

Of course after separating and landing, I realized that while I had mounted a good arrangement of RCS quads on the lander, all of the actual monoprop supply was on the transfer stage in that big tank. So after returning from the surface, I had to dock with a powerless transfer stage using a lander with no RCS. That was an exercise in patience.

And once that was done I still didn't have enough dV to get home and had to send a rescue tanker.