Simulating two-stage Rockets in RASAero II?

[AlexaSpace]

I am trying to simulate my college's high powered rocket, in the past we have used Open Rocket which is very straightforward about adding separation events and separate recovery systems per stage. We heard that RasAero II has a better estimation of supersonic effects like Wave Drag, and a better system for specifying fin cross-sections. So we are attempting to make the switch to RasAero. I am having trouble scheduling recovery events (and stage seperation) within the flight simulation itself, and adding our drogue/main chutes for each stage, there is no option to specify within recovery. I know that RASaero doesnt directly sim two stage rockets, but is there any way to specify these events? Thanks!

 

[user 30299]

Try sending a PM to "Chuck Rogers" on TRF. It's his program.

 

[Chuck Rogers]

I am trying to simulate my college's high powered rocket, in the past we have used Open Rocket which is very straightforward about adding separation events and separate recovery systems per stage. We heard that RasAero II has a better estimation of supersonic effects like Wave Drag, and a better system for specifying fin cross-sections. So we are attempting to make the switch to RasAero. I am having trouble scheduling recovery events (and stage seperation) within the flight simulation itself, and adding our drogue/main chutes for each stage, there is no option to specify within recovery. I know that RASaero doesnt directly sim two stage rockets, but is there any way to specify these events? Thanks!

Alexa:

For Booster (Stage-1) stage separation and delaying the ignition of the Sustainer (Stage-2) stage see Running the RASAero II Flight Simulation in the RASAero II Users Manual starting on Page 98, in particular see Page 103. RASAero II assumes that if you make the Booster Separation Delay equal to zero seconds, then the Booster will separate at the end of the Booster motor thrust curve. Theoretically the Booster could drag separate before that (during tail-off of the motor burn), but RASAero II assumes that the Booster will separate at the end of the Booster motor thrust curve plus the Booster Separation Delay. You can also set the Booster Separation Delay to something different from zero seconds, if you are delaying the Booster separation and then controlling the point where the Booster is separated.

For Recovery RASAero II assumes that the parachute is deployed at apogee. A drogue parachute can be deployed at apogee, and then a main parachute can be deployed at an altitude above ground level entered by the user. See the Recovery Inputs section in the RASAero II Users Manual on Pages 81-82.

As others have noted, if you'd like you can Private Message (PM) me here, or you can e-mail me at the e-mail address on the User Support page on the RASAero web site ( www.rasaero.com ).


Charles E. (Chuck) Rogers
Rogers Aeroscience