Satellofter: precision satellite launcher

[frenchie16]

So, this being my first post, I'll start with something pretty basic, but elegant and cool, in my opinion anyway. It's a satellite lofter. What I like about it is that it can be flown pretty much by a checklist, as each stage of the rocket corresponds to a stage of what you need to do to make it orbit. To use the .craft you'll need Wobbly Rockets 1.09 and SIDR&SD 1.0 updated .craft now requires 1.1 (and obviously, thanks to the people who made those excellent parts packs!)

Now then, flight profile/checklist/instructions, with photos below. I've also attached the .craft. I don't know why some photos are bigger than others, sorry about that.

Pre-launch: toggle SAS on, toggle 'precision' control mode (I recommend leaving them in those states the entire time, except disabling SAS as noted below).

Launch: leave throttle at 50%. Rocket should stay straight, use manual correction as needed to stay vertical.

SRB burnout: stage to eject SRBs. Throttle up to 100%. Continue vertically, rolling 90 degrees to starboard such that north is to the right on the gimbals.

First stage burnout: stage to eject first stage. You should now be out, or almost out, of the atmosphere. The second stage will insert you into your orbit. Before activating the second stage, pitch down to 45 degrees (deactivate SAS before pitching, reactivate after.)

Activate stage 2. (You should be out of the atmosphere at this point.)

Second stage ~50% fuel: pitch down to 20 degrees.

Second stage burnout: Eject second stage. The shrouds will fall away, revealing your command module and satellite.

Pitch down to the horizon and activate the third stage.

accelerate to around 2km/s, then throttle down to 0%. Decide at what altitude you wish to orbit (It will do 100km very nicely, as I demonstrate in the pictures) and calculate the velocity you will need. Maintain your velocity as necessary for your orbit, and, as needed, pitch to straight up or straight down and burn to adjust vertical velocity until you have a stable orbit. During this time you should be able to leave roll and yaw alone (or make very minor adjustments) and use pitch and throttle to settle into an orbit.

Orbit achieved: separate satellite.

Deorbitting strategy is up to you, I recommend retroburning to enter a hohmann transfer orbit to at or just under 35km. If you do this when the launch facility is directly below you, but on the far side of the planet, you should have enough fuel left to maneuver into a landing back at the pad, though I have yet to get closer than having it on the horizon. (I recently added a second fuel tank to the final stage, this should make it much easier to land accurately; I kept running out of fuel whilst trying to maneuver closer.)

[sirmonkey]

very nice clean design. way better then my unrealistic satellite launchers.

[Tim_Barrett]

Nice, but too bad everyone uese pretty much the same design since those parts came out on sunday punch's part pack.

[frenchie16]

Nice, but too bad everyone uese pretty much the same design since those parts came out on sunday punch's part pack.

What design do you mean? Though I am sure they are out there, I personally haven't seen another design that uses the 2m payload fairings before going down to 1m and then back up to 2m, nor one with a powered command module attached nose-first to the satellite for orbital maneuvering. Still, it is a pretty generic design I suppose.

[sirmonkey]

What design do you mean? Though I am sure they are out there, I personally haven't seen another design that uses the 2m payload fairings before going down to 1m and then back up to 2m, nor one with a powered command module attached nose-first to the satellite for orbital maneuvering. Still, it is a pretty generic design I suppose.

because no one has until now.. ignore him.. hes a useless thread crapper..

[Tim_Barrett]

What design do you mean? Though I am sure they are out there, I personally haven't seen another design that uses the 2m payload fairings before going down to 1m and then back up to 2m, nor one with a powered command module attached nose-first to the satellite for orbital maneuvering. Still, it is a pretty generic design I suppose.

It was pretty much designed for the 2-1-2 meter design. So yes it is generic, but now everyone can/will do it.

However kudos to a rocket that works! ;D

[Bigred2989]

This thing works great! I love how after you jettison the boosters on the first stage it naturally starts to tip over into an orbiting angle. I was actually able to orbit Kerth all the way back to the launch pad. I screwed up my reentry though and ended up gaining escape velocity.

[frenchie16]

On the topic of the 2-1-2 meter design, I thought it would be far too wobbly given the weaker strength of the connection nodes on 1m parts; I was right, which is why it needs the set of struts between the first and second stages. Stability-wise, it works better to have a 2m stage below the fairings followed by a 2 or 3m stage, as in Sunday Punch's example videos. But it looks so much nicer with 2-1-2. Reminds me of the Ariane-4, for instance.

In any case, I'm aware it's a pretty typical design, I just rather like the way it flies: it feels very 'realistic' in that each stage has a job to do and it has just enough, but not too much, power to reach orbit.

[frenchie16]

Updated OP with new .craft, which is compatible with SIDR&SD version 1.1.

[Aladran]

Nice one, i got a similar one, very fonctional!

I also like the new payload cove!

[Bigred2989]

Now I doesn't perform anywhere near how well the first version did. It goes horizontal at around 10,000 and starts falling. Even if I start with full throttle and SAS on I still get nowhere near orbital altitude. Any advice?

[frenchie16]

Now I doesn't perform anywhere near how well the first version did. It goes horizontal at around 10,000 and starts falling. Even if I start with full throttle and SAS on I still get nowhere near orbital altitude. Any advice?

I didn't test the new version fully. I'll check it out and update as needed.

EDIT: Unless I posted the wrong/an earlier .craft file, you have one of two problems:

first, the satellofter II file is meant for people with SIDR&SD version 1.1, so make sure you've upgraded?

Second, perhaps you forgot to throttle up after ejecting the SRBs. I did three test launches; in the second I had very similar problems to you, I think it was because I forgot to throttle up.

Also, it is possible you are just not manually correcting enough. The new version needs a bit more manual correction than the old one. Until you are about to ignite the second stage (the K2-X on the 1m fuel tank), you should keep it as close to vertical as you can. Once your velocity vector drifts more than about 10 degrees or so from vertical, there's not much you can do to salvage it.

[Bigred2989]

I'm pretty sure I updated the parts, otherwise it would have never loaded the ship. I think the problem may lie in the payload. You used to have the mini decoupler on it but now you have the nano one. Perhaps the weight distribution was just the right balance in the last version.

[frenchie16]

I'm pretty sure I updated the parts, otherwise it would have never loaded the ship. I think the problem may lie in the payload. You used to have the mini decoupler on it but now you have the nano one. Perhaps the weight distribution was just the right balance in the last version.

I dunno, maybe. I can still get it into orbit fine with the nano-decoupler version. Just leave the SAS on and keep it vertical, and don't forget to throttle up to 100% after ejecting the SRBs, it should work fine.