Wanted: Idiot proof SSTO

[Fail-o-matic]

In search of a SSTO that is NEAR usable. I suuuuuck at flying ssto but would like to haul a probe(or probe with a kick motor, I like having a purpose of a flight) KAA is about to revoke my license due to the debris fields I have created and just can't get the hang of it even with flight profiles people provide. I either slog to low and slow or don't get enough speed before trying to go rocket mode and run out.

Edited September 19, 2014 by Fail-o-matic

[MarvinKitFox]

Consider a rocket-based SSTO?

[Alshain]

Why don't you post some of your designs as pictures and we can help you improve them. I could give you some planes, but no plane is idiot proof, you have to know how to fly.

[Fail-o-matic]

I usually grab other peoples designs to fly and try to follow their instructions but usually doesn't work out. Usual flight profile is fly to 20k, gain as much speed and punch out with rockets. I understand the concept, but putting into practice is maddening, just looking for a proven plane that isn't finicky...just so I can taste success.

Thanks

[Alshain]

Well, with NEAR that's not so true. You want to fly till your intake air is low but not gone, level out to gain speed (don't be afraid to go back down to get more air), and depending on the engines your using, pitch up just before your speed is too fast for the engine (TurboJets apparently die around 1800m/s, Rapiers 1700m/s) If you start seeing reentry heat, try to climb a little higher, unless that takes you out of the air in which case your done with the air breathers, pitch up and go till the die (or for dual engines, shut them off just before they die). Just be careful not to pitch too hard at those speeds, however in that high an atmosphere you shouldn't have too big a problem. I can get my apoapsis to around 40k before switching, with NEAR installed.

Once you switch, your basically doing the same as a rocket, no punching out, that's not good. Level off just above the artificial horizon and adjust your throttle to maintain 1 minute to apoapsis until your apoapsis is at 70-75k. You should be burning very low throttle for most of the time.

I'll post a craft for you later tonight.

Edited September 17, 2014 by Alshain

[Franklin]

I used to be awful at getting spaceplanes to orbit until I started maximizing horizontal speed. Now I can get a turd with a RAPIER strapped to it into orbit under FAR/NEAR.

Climb (straight up, who cares) to about 20-30K, then level out and just keep goin. Go until you break 1200-2000m/s horizontally. As long as your apoapsis stays ahead of you you're fine. Then begin to climb again slowly, and as your intake drops to 0, switch to your rockets (or as your RAPIERs kick over), and begin the final climb. You should be able to enter orbit easily.

Learning it's fast and horizontal with spaceplanes, not strong and vertical like rockets made a world of difference.

[Alshain]

I used to be awful at getting spaceplanes to orbit until I started maximizing horizontal speed. Now I can get a turd with a RAPIER strapped to it into orbit under FAR/NEAR.

Climb (straight up, who cares) to about 20-30K, then level out and just keep goin. Go until you break 1200-2000m/s horizontally. As long as your apoapsis stays ahead of you you're fine. Then begin to climb again slowly, and as your intake drops to 0, switch to your rockets (or as your RAPIERs kick over), and begin the final climb. You should be able to enter orbit easily.

Learning it's fast and horizontal with spaceplanes, not strong and vertical like rockets made a world of difference.

Same here, the real trick is learning to flirt with the edge of your intake air limits, only at that altitude can you gain maximum speed without tearing your plane apart (even in NEAR that can happen, just not as bad).

However, I disagree with the strong and vertical rockets. Rockets are better horizontal too.

[Franklin]

However, I disagree with the strong and vertical rockets. Rockets are better horizontal too.

No, for sure. I just mean learning how to get a spaceplane into orbit took some re-education over everything we're told about getting a rocket into orbit under stock (straight up to 20K, bank left, full throttle until 70K).

I understood the boilerplate ascent recipe changes under FAR/NEAR, but in the back of my mind it was still strong & upward for success that stock drilled into me.

[Alshain]

OK, this is a simple SSTO designed for rescue contracts. It does take a little skill to land as the gear is a bit close together, but it flies pretty easily, actually it's a little sensitive on the controls so be careful there.

1. Take off and go at a comfortable AoA to get yourself to 24km, by the time you hit 24km your prograde needs to be on the artificial horizon as seen in the first image. Note the intake air, I'm flirting real close the edge here.

2. When you hit 1200 m/s your going to start losing your engines (you will hear it), pitch up gently to use that speed for a last bit of climb. Hit the 4 key to shut off the engines before they die or you will flat spin. I almost went too far (Fourth image)

3. Fire the rocket stage and pitch back down to 5-10 degrees, raise and lower the throttle to maintain 1 minute to apoapsis as closely as possible. (Fifth Image) When your apoapsis hits 70-75km, your periapsis should also be positive, in fact your periapsis might just exceed the apoapsis and they will flip, if that occurs you won't be able to maintain 1 min to apoapsis anymore, it will jump way up, but that's a good thing. (Eighth image)

4. DO NOT CHANGE THE SHAPE OF YOUR AIRCRAFT TILL YOU REACH 70K. That means do not turn to point toward a maneuver node, you can plan, just don't change your heading.

5. Circularize as usual, the burn should be only a few seconds. Always circularize just out of the atmosphere, if your target is a 300km orbit, circularize at ~70k and then extend it after. The last image shows a 1 second circularizing burn, about as perfect as you can get.

EDIT: The 3rd image was a different flight where my engine action group (4) got messed up do to my incessant tweaking. Not sure how the picture got in there, but I'm not removing it because it would mess up the numbering above.

EDIT2: For the return I manually shut off the aerospike and pump fuel back to the jets before I leave space. Gives you the option of a powered landing if you miss the runway.

Craft File

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Edited September 17, 2014 by Alshain

[Taki117]

Check out this thread.

[Pecan]

LV-10-1 is still the simplest SSTO I know for a decent payload (in its case 10t, hence the name)

LV-10-1 + Cartographer Heavy Launch

Chapter 5 of the tutorial in my signature.

[Wanderfound]

See http://forum.kerbalspaceprogram.com/threads/90747-Kerbodyne-SSTO-Division-Omnibus-Thread?p=1402927&viewfull=1#post1402927 for a good basic spaceplane and http://forum.kerbalspaceprogram.com/threads/90747-Kerbodyne-SSTO-Division-Omnibus-Thread?p=1402927&viewfull=1#post1402927 for an atmospheric trainer.

And http://forum.kerbalspaceprogram.com/entries/1646-How-to-fly-a-spaceplane-to-orbit?bt=6775 for a piloting guide.

Edited September 18, 2014 by Wanderfound

[Alshain]

OK, so I tried to de-orbit with the plane I posted earlier and remembered why I stopped using it. It's too unstable with DCOM. Try this one, it's much better both going up and down. Same ascent I outlined before, just different plane and this one has only one jet so you don't have to turn it off, just let it flame out.

https://dl.dropboxusercontent.com/u/9097777/Falcon%20R2.craft

[Fail-o-matic]

Just a thanks to those that posted with info and suggestions. I actually made it into orbit, took a try or 2 but finally made it. Re-entry was an adventure, totally overshot the runway and had to turn around and crashed(definitely not a flight simulator, but no joystick either)

[Alshain]

Just a thanks to those that posted with info and suggestions. I actually made it into orbit, took a try or 2 but finally made it. Re-entry was an adventure, totally overshot the runway and had to turn around and crashed(definitely not a flight simulator, but no joystick either)

Practice makes perfect on the landings. It might be easier to practice with an atmospheric plane rather than an SSTO, unless you've already done that an just had trouble this time.

Be sure to mark the thread as answered.

[Sirrobert]

Well techniqually, this is an SSTO, 30 tons payload

[SRV Ron]

Last Night's experiment using KW Rocketry and Nova Punch mods to find the ideal combo of fuel cans and booster engine. Payload is a second stage with a one Kerbal pod.

[KerikBalm]

2. When you hit 1200 m/s your going to start losing your engines (you will hear it), pitch up gently to use that speed for a last bit of climb. Hit the 4 key to shut off the engines before they die or you will flat spin. I almost went too far (Fourth image)

I direct you to this post: http://forum.kerbalspaceprogram.com/threads/84217-Explaining-burnout-asymetry?p=1234436&viewfull=1#post1234436

Which I found to be very helpful, and as a result, I've rebuilding my SSTOs... no more asymetrical flameouts for me....

I used to find it so much easier to milk a single turbo or rapier for all it was worth, but couldn't do the same for pairs, not any more