OHM HARP
- Thread starter OrbitHangar
- Start date
(I had to try it....)
MaverickSawyer
Acolyte of the Probe
Works Great! however, I found that the first stage can tumble pretty badly upon launch, though nothing else seems to do that...
boogabooga
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I'm a fan of HARP because I think it has one of the fastest times from launch to orbit of anything.
The tumbling is probably because of HUGE dynamic pressures at launch, since it leaves the barrel at Mach 3. Launching with about 47 degrees elevation helps because the dynamic pressure isn't so high for so long.
This gets me to at 1200km circular orbit easily without any modification to the firing velocity and without tumbling:
1) Launch a Martlet due east with 47 degrees elevation
2) Apogee should be about 54km. Coast all the way up to 48k. By this time, you should automatically have a pitch of about 30 degrees to the horizon.
3) Fire first stage. Let it burn out. Apogee should now be well over 100km, but not super high
4)Within seconds of first stage burn out, it should be safe to jettison the first stage, the nosecone, and both fairings.
5) Set the second stage to prograde autopilot. Fire the second stage when time to apogee is about 30 seconds.
6) Drop the second stage as soon as it burns out. Then, within a few seconds, fire the third stage.
7) After burn out, you should have about a 600-700ish km x 150ish km orbit. The default "payload" has high drag, so wait till you get to about 180km before you release it from the third stage.
8) After that, you have the payload rocket with which to tweak your orbit. I can get to about 1200km fairly easily.
The tumbling is probably because of HUGE dynamic pressures at launch, since it leaves the barrel at Mach 3. Launching with about 47 degrees elevation helps because the dynamic pressure isn't so high for so long.
This gets me to at 1200km circular orbit easily without any modification to the firing velocity and without tumbling:
1) Launch a Martlet due east with 47 degrees elevation
2) Apogee should be about 54km. Coast all the way up to 48k. By this time, you should automatically have a pitch of about 30 degrees to the horizon.
3) Fire first stage. Let it burn out. Apogee should now be well over 100km, but not super high
4)Within seconds of first stage burn out, it should be safe to jettison the first stage, the nosecone, and both fairings.
5) Set the second stage to prograde autopilot. Fire the second stage when time to apogee is about 30 seconds.
6) Drop the second stage as soon as it burns out. Then, within a few seconds, fire the third stage.
7) After burn out, you should have about a 600-700ish km x 150ish km orbit. The default "payload" has high drag, so wait till you get to about 180km before you release it from the third stage.
8) After that, you have the payload rocket with which to tweak your orbit. I can get to about 1200km fairly easily.
MaverickSawyer
Acolyte of the Probe
Running at .1X time helps as well. I encounter this quite a bit with high speeds in atmospheres.
AnakinSkyobiliviator
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I hope this works for 2010-P1, I want to launch some 1 megaton nukes by Atlav...
boogabooga
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It does
MaverickSawyer
Acolyte of the Probe
It works REALLY well.
