Orbit, land, orbit, land

[The_Duck]

Build a rocket that:

1. Launches into orbit (any orbit).

2. Then deorbits and lands safely.

3. Then launches again from its landing site into orbit (any orbit).

4. Then Deorbits and lands safely again.

This is something like what a manned mission to a moon or planet would be like, except we don't have any other bodies to land on except the one planet.

I've been trying to do this for quite a while and only just now succeeded. This challenge requires a really huge rocket (at least with stock parts) since you have to put into orbit a rocket that is itself capable of orbit. 0.9x1's struts and icon grouping make building a rocket of the necessary size much less painful.

Doing a safe landing was also pretty difficult for me. If you're going to try this I suggest you check out the lander leg part at kerbalspacerepository.com.

[DoctorEvo]

I was JUST THINKING that that'd make a pretty cool challenge.

Let me see what I can cook up...

[Cannon_Fodder]

The question is have you pulled this stunt off?

[robotroadkill]

I've done this using add-ons. The lunar lander has an insane amount of fuel, and can pull off the 'land, orbit, land' portion on its own, if I remember correctly. Of course, stock parts is usually a requirement for these quests, but it's not clear from the post if that is part of the challenge.

[Aladran]

Build a rocket that:

1. Launches into orbit (any orbit).

2. Then deorbits and lands safely.

3. Then launches again from its landing site into orbit (any orbit).

4. Then Deorbits and lands safely again.

This is something like what a manned mission to a moon or planet would be like, except we don't have any other bodies to land on except the one planet.

I've been trying to do this for quite a while and only just now succeeded. This challenge requires a really huge rocket (at least with stock parts) since you have to put into orbit a rocket that is itself capable of orbit. 0.9x1's struts and icon grouping make building a rocket of the necessary size much less painful.

Doing a safe landing was also pretty difficult for me. If you're going to try this I suggest you check out the lander leg part at kerbalspacerepository.com.

Can we see your beast?

[zarakon]

I kind of doubt this is possible to do with stock parts

I've built some huge rockets for top speed (over 8km/s with the new struts) which I think would be great for this challenge with their large quantities of fuel, except for one glaring problem: huge rockets are virtually impossible to steer.

[The_Duck]

Here's a rocket that can do this. It uses three non-vanilla parts: the radial-mount parachute, the lander leg, and the radial stack decoupler found at kerbalspacerepository.com. These are all really nice mods. The fuel tanks and engines are all vanilla.

On the launchpad:

After the first landing (you can land on water, which is solid and nicely flat!):

.

The lander uses three radial-mount parachutes to slow the rocket down and align it vertically, but you still need to use carefully applied engine thrust to bring the vertical speed down to something survivable.

[The_Duck]

Here's a rocket that can pull this off with only vanilla parts! I used depleted SRBs as lander legs, which worked moderately well. Powered landings are pretty tricky to get right, I usually mess it up.

On the launchpad:

The lander:

[Rocketeer]

You need to basically transport a 3 tank rocket into orbit and back down. From the ground, 3 tanks are enough to achieve orbit and return under a powered landing.

[DoctorEvo]

You need to basically transport a 3 tank rocket into orbit and back down. From the ground, 3 tanks are enough to achieve orbit and return under a powered landing.

That was my plan exactly. My 'Barracuda,' as I named my design, was just barely not up to the task, even after I wrapped it in three stages of SRBs. Back to the drawing board, I suppose.

[mixinghoney]

Now that will be difficult .. not for me 8)

[sirscott]

Bump with a potential soloution. Ive been working on a lander with some mod parts (Sunday punch , silskos etc) and ive managed to produce a craft that can succesfully land and then attain orbit. Now I just have to put together a mega-booster that wont detonate trying to put the child-craft into orbit.

[foamyesque]

I have a lifted at the two and three-quarters tank to orbit, so that at least shouldn't be an issue. The question is having it survive the first landing.

[sirscott]

I promised more information , so here I am with screenies of tonights practice runs.

Now , first off I should tell you about the craft at the core of this design , the Proton. It utilises a number of mods from Sunday Punches wobbly rockets and Novasiliskos doughnut R&SD , but none that I think are unrealistic. When first pondering this challenge I came to the conclusion that the best way to approach it would be in a number of stages , working backward:

1. The development of a super-lightweight orbiter and Launcher combo

2. Production of Additional stages to configure the Launcher-Orbiter into a lander

3. Construction of a primary booster to launch the completed lander into its initial orbit

The result of stages 1 & 2 was the Proton lander

As you can see , its a mess of struts and legs , but it goes together like a dream. The main stack is simply a double length tank from Nova's pack that powers a moderate engine. Attached to the top is the orbiter , a lightweight tank and small engine with some bolt on verniers for stability (And which are in fact the only SAS equipment on the entire craft). Completing the Launcher are the two small SRBs fitted to radial mounts. For landing there are four of novas long Radial decouplers , each of which bears two parachutes and a landing leg. At the base of the lander is a small tank of fuel and a second engine , used for deceleration during landing

In the Practice sequences ive been conduction , the lander has been boosted to Approx ~ 5000m by a selection of large SRBs latched onto the bottom. Once loosed from this chariot , the chutes on the lander immediately deploy and slow the fall to about 70 m/s. At this speed the chutes would be ripped from their mountings so the Liquid engine at the bottom of the stack is throttled up to the hilt at about 1250m. After full chute deployment , speed drops to around 8 m/s and falls to 7.8 by the time the lander touches the ground. So far I have had most success with water landings , as uneven land surfaces tend to put the full pressure of landing onto only one leg , shearing it off.

The vehicle is too heavy for the landing motor to lift on its own , so the lander comes to rest pretty quickly once the chutes have been released. The Landing motor is then throttled back and discarded by releasing the decoupler that connects it to the bottom of the stack. The legs have been precisely positioned to allow this to occur. The next stage contains the Proton Launcher , and the decouplers containing the legs and defunct chute stanchions are triggered at the same time as the main engine and SRBs.

The SRBs give out at about 3500m , but the ship is very light , allowing the double tank to carry the orbiter up to LEO altitude , if not speed. The Orbiter then boosts to the correct velocity , leaving enougth gas for a re-entry burn.

So far I have made three successful landings and re-ignitions out of 5 attempts. I am now working on stage three of the plan to produce a launcher capable of carrying the Proton lander into orbit.

[andydouble07]