Flight Question Changing Orbits after launch

[nubula2]

Hi all,

Last night i did the Launch at sunrise scenario with the Shuttle, for practice etc. Got to orbit, SRBs went off, ok no problem, but MECO didnt happen. At the time i thought i was way out of the atmosphere, but i plummeted big time. I assume i wasnt high enough? what is the height and angle to be at for MECO to fire? At one point i was upside down over US and my ME was still attached? :facepalm:

 

[orb]

You couldn't be in a stable orbit at the time SRBs went off. Periapsis must have been still in the Earth's core at that time.

The altitude and pitch angle at the time you perform engine cutoff don't matter that much if your periapsis is still well below the planet's surface. Switch one of the MFDs to orbit mode and watch the PeA (periapsis altitude) or Ecc (eccentricity). You should do MECO when periapsis is above the surface or when eccentricity is close to 0. Also, don't burn straight up.

 

[nubula2]

thanks orb

 

[Donamy]

Remember, you will also have to use the OMS engines, to circularize your orbit at apoapsis, to remain in orbit.

 

[statickid]

Hi all,

Last night i did the Launch at sunrise scenario with the Shuttle, for practice etc. Got to orbit, SRBs went off, ok no problem, but MECO didnt happen. At the time i thought i was way out of the atmosphere, but i plummeted big time. I assume i wasnt high enough? what is the height and angle to be at for MECO to fire? At one point i was upside down over US and my ME was still attached? :facepalm:

Couple quick questions:

1. "SRBs went off...but MECO didnt happen."
2. "what is the height and angle to be at for MECO to fire?"
3."At one point i was upside down over US and my ME was still attached?"

1. Unless you are using a launch program MECO happens when you either press * (or hold zero) or run out of fuel in the External Tank (ET)
2. "MECO to fire" MECO: Main Engine Cut Off
3. ME: Main Engine, I don't think you can detach the main engines from the space shuttle without something really bad happening. Are you referring to the external tank? If so, with models that I have used, you usually have to release the tank with some action key.

also, if you are upside down over the US did you complete a whole orbit or did you launch towards the west? If you completed a whole orbit, then it's possible that you DID achieve orbit, but forgot to raise your Pe above the atmosphere.

 

[nubula2]

Couple quick questions:

1. "SRBs went off...but MECO didnt happen."
2. "what is the height and angle to be at for MECO to fire?"
3."At one point i was upside down over US and my ME was still attached?"

1. Unless you are using a launch program MECO happens when you either press * (or hold zero) or run out of fuel in the External Tank (ET)
2. "MECO to fire" MECO: Main Engine Cut Off
3. ME: Main Engine, I don't think you can detach the main engines from the space shuttle without something really bad happening. Are you referring to the external tank? If so, with models that I have used, you usually have to release the tank with some action key.

also, if you are upside down over the US did you complete a whole orbit or did you launch towards the west? If you completed a whole orbit, then it's possible that you DID achieve orbit, but forgot to raise your Pe above the atmosphere.

Thanks, yeah i finally can get into a stable orbit now.