jer@peora.UUCP (J. Eric Roskos) (03/09/86)
> This may be a stupid question, but what if you blow the SRB loose and > let it continue on it's merry way alone? The only problem I see would > be the danger of the exhaust from the launching SRB igniting the main > tank. We all know how nasty *that* can be. I guess I answered my own > question. I don't know very much about this sort of thing, but I think the SRB also might not fly straight on its own; it might turn around and head inland, for example... in order to fly straight a rocket has to obey various aerodynamic properties, including the famous "the center of gravity has to be ahead of the center of pressure" one. (Back in the old days when I used to build little rockets [which actually wasn't so long ago since I also did it briefly to maintain my sanity while completing my thesis in grad. school] an informal way to test this was to tie a string around the rocket and adjust it so that the rocket just balanced; then you'd spin the string around in a circle, and if the rocket flew straight, the above principle held for that design and you could be fairly sure it would be stable in flight.) The point being that just because it's long and cylindrical and the exhaust comes out the back with the thrust along the axis of the rocket isn't sufficient to insure it will fly straight... try the above test on a pencil, for example. (Other bad things can also happen; e.g., the rocket can go into a "gravity roll" in which the rocket rotates such that the force of gravity slowly pulls the forward end of the rocket around toward the ground, so it heads downward, which was apparently what was happening to the SRBs after they came loose from the vehicle. I think that these are used during normal rocket launches to put them into a proper trajectory.) Note I said "might not" above; I don't profess to know anything at all about aerodynamics or SRBs, and just offer the above more as a question for some knowledgeable person to answer... -- UUCP: Ofc: jer@peora.UUCP Home: jer@jerpc.CCUR.UUCP CCUR DNS: peora, pesnta US Mail: MS 795; CONCURRENT Computer Corp. SDC; (A Perkin-Elmer Company) 2486 Sand Lake Road, Orlando, FL 32809-7642 LOTD(6)=B ---------------------- Amusing error message explaining reason for some returned mail recently: > 554 xxxxxx.xxxxxx.ATT.UUCP!xxx... Unknown domain address: Not a typewriter (The above message is true... only the names have been changed...)