I didn't go back and look, but iirc, psas flight data has the same pressure glitch at motor burn-out. Previously we have attributed the glitch to changes in the pressure field over the vehicle surface due to the presence or absence of motor plume.
This explanation may be wrong. In particular at supersonic velocities motor plume cannot effect the pressure field on the forward part of the vehicle. Perhaps motor exhaust is somehow leaking into the interior of the airframe and pressurizing the entire structure? If that were the case then running a hunk of tubing from the pressure sensor directly to the outside would eliminate the effect. --- The (calibrated) pressure sensor is probably more accurate in determining altitude at apogee than the accelerometer. You could rescale the filtered accelerometer data to match the pressure determined apogee. That should provide a better calibrated view of the burn-out pressure glitch. --- I'm a little confused as to why all the accelerations are positive. Even accepting that the acceleration on the pad reads as +1 gee it really seems like the initial post-burn-out acceleration should be negative. (2009.04.22) kei...@keithp.com: > [..] > Taking a look at the results, you'll see that the speed computed from > both pressure sensor and altimeter track very closely, except where the > pressure sensor saw some noise during motor burn-out. The cause of this > is as yet unknown. _______________________________________________ psas-avionics mailing list psas-avionics@lists.psas.pdx.edu http://lists.psas.pdx.edu/mailman/listinfo/psas-avionics
