Challenge: Only thrust at apoapsis

[thereaverofdarkness]

The challenge is to see how far you can get by only lighting your engines at apoapsis, and always burning at maximum power until the fuel runs out. You can rotate your craft to waste fuel. For initial stages, you just watch your altitude and wait till the numbers stop going up, and then pop the next stage. Solid fuel rockets may be very useful for this challenge, since you aren't allowed to turn them off anyway. You may throttle back an engine slightly if you have to to prevent it from overheating. I won't say you have to use stock parts, but I'd rather not see people using anything that makes this challenge too easy. No RCS thrusting allowed, RCS may only be used to turn the vessel. You can use QWEASD for RCS, but you may not use IJKLHN. Same goes for Kerbal EVA backpack, although the default controls are reversed. Finally, parachutes are not allowed at all, and wings are not allowed for landing. I'd advise against using wings at all, but you may use ejectable wings if you like. Wings must be detatched above 5000m when landing.

All of the following point listings are additive, so every mark you complete, you get the points for it. Also, landing by my definition only means that at least one Kerbal survived.

30km - 1 point

50km - 2 points

70km - 5 points

achieve Kerbin orbit - 10 points

land on Kerbin after reaching 30km - 40 points

land on Kerbin after reaching 50km - 60 points

land on Kerbin after reaching 70km - 100 points

achieve Münar orbit - 10 points

land on Mün - 250 points

achieve Minmus orbit - 10 points

land on Minmus - 150 points

escape Kerbin - 15 points

enter orbit with Eve or Duna - 25 points

land on Eve - 100 points

land on Duna - 250 points

achieve Ike orbit - 10 points

land on Ike - 400 points

achieve Gilly orbit - 20 points

land on Gilly - 800 points

enter orbit with Moho or Jool - 40 points

enter orbit with Dres or Eeloo - 60 points

land on Moho, Dres, or Eeloo - 600 points

achieve orbit with any Joolian satellite - 25 points

land on any Joolian satellite - 500 points

descend through Joolian atmosphere and take beautiful screenshot - 25 points

Edited July 24, 2013 by thereaverofdarkness
updated points for difficulty of landing without atmosphere

[reilem]

And what is "At apoapsis" since your craft is always moving, the moment where you are exactly on your apoapsis is only a fraction of a second. How much before and after the apoapsis is still considered apoapsis? This seems a little flawed if you ask me.

Unless you mean: at apoapsis (0s to Ap) you start burning and then you let it burn until it runs out which can then be several minutes later?

[Kosmo-not]

How can you gain any altitude if you can only burn at apoapsis? I don't think you understand how orbital mechanics work.

[stupid_chris]

At first I thought he might mean thrusting at the prograde vector, but then again, I don't see how that makes sense either :l

[Pursuedtank]

Perhaps we are supposed to start to burn at apoapsis and then see how far we can go without reducing the thrust. That's the best I can think of that still makes sense.

[allmappedout]

I...I..I think I know what he means guys! I think he means for every SOI change you may only burn at Ap? Otherwise none of the rest of the challenges make any sense? Like how could you even land on the Mun if you had to be at full thrust from Ap burn at Kerbin through to Landing? Presumably, you have to set up a stage carefully so that your dV exactly matches your requirement. Which is kinda brutal really, and doesn't reward landing on an atmospheric body as much as it is.

Also, it's courtesy to post your own attempt at a challenge when posting one...

[thereaverofdarkness]

only lighting your engines at apoapsis

I never said you have to stay at apoapsis during the burn. You just have to be at apoapsis when you ignite the engines. So when doing a landing, you want to make sure that your engine burn finishes with you in an orbit until you're ready to make an entry. In thick atmosphere, you can spend long portions of the descent at apoapsis, so this gives you a nice window to ignite engines. Other tricks may involve using slow-burning engines to land right as you finally slow down. Well now that I think about it, I realize it would be pretty difficult to time your burns for a landing on an atmosphere-free body if you can only ignite at apoapsis. It might be doable if you start with an extremely tight orbit.

I played around with this challenge for a while and came up with a craft that could leave Kerbin orbit and very nearly escape the Kerbol system, but I'm too lazy to bother easing into orbit with another planet or even posting screenshots. I really just posted this to give you guys something to do if you're bored, but I like to set limits for scoring as high as possible, in case people achieve it. I'll update the points to account for the increased difficulty.

[stupid_chris]

I'm sorry, but I still really don't understand the target of your challenge. Really, I don't think anyone will do this challenge until you post your own attempt and show us how it's done.

[Rainbowtrout]

Neither do I. Please take a look at the challenge guidelines next time.

In before the mods!