Excellent video. It appeared as though I was going to get a straight shot at the Body Flap of Columbia during SRB ignition during STS-1, but it was blocked by "smoke". The views given for SRB ignition for STS-2,3,4 clearly show the body flap.I have yet to see a SRB ignition video showing the 1-1/2' displacement of the body flap during STS-1 SRB ignition. To remedy the damage/potential body flap damage, improved acoustical energy management was used. I am under the impression that this may be where the "water bags" on the MLP were used?
Quote from: Hog on 07/22/2017 04:44 pmExcellent video. It appeared as though I was going to get a straight shot at the Body Flap of Columbia during SRB ignition during STS-1, but it was blocked by "smoke". The views given for SRB ignition for STS-2,3,4 clearly show the body flap.I have yet to see a SRB ignition video showing the 1-1/2' displacement of the body flap during STS-1 SRB ignition. To remedy the damage/potential body flap damage, improved acoustical energy management was used. I am under the impression that this may be where the "water bags" on the MLP were used?That and the large pipes around the SRB exhaust holes on the MLP. These were known as the Ignition Overpressure (IOP) suppression system. The smoke trails are from the yaw jets. The yaw jets aren't shut down until until below Mach 1.
From what I've read, the rcs is phased out during descent in the order that the aerodynamic control become effective. Pitch and roll become effective through the flaperons and body flap at some mach, but until the aoa comes down to near 0 the rudder is blanketed and ineffective. So the yaw rcs is used until below mach 1.