Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sdd.hp.com!ucsd!pacbell.com!att!cbnews!cbnews!military Newsgroups: sci.military Subject: Re: Ejection seats Message-ID: <1991Feb15.065658.9396@cbnews.att.com> Date: 15 Feb 91 06:56:58 GMT References: <1991Feb4.052511.15316@cbnews.att.com> Sender: military@cbnews.att.com (William B. Thacker) Organization: Me, Myself, and I Lines: 56 Approved: military@att.att.com From: uunet!mcgp1!flak (Dan Flak) In article <1991Feb4.052511.15316@cbnews.att.com> voder!nsc!dtg.nsc.com!alan@decwrl.dec.com (Alan Hepburn) writes: >It seems to me that a canopy designed to withstand >air pressures of supersonic flight would be extremely difficult to >punch through with a slow-moving seat, or head. Does anyone out there >have any real data on this? Can a pilot survive a punch out through >a canopy? In a word -- yes. I've known one pilot who has. To get to the ejection triggers in some type seats, you have to raise the handles protecting the triggers. This is supposed to blow the canopy. When you squeeze the trigger, the seat is supposed to go a quarter of a second later. Hopefully the canopy is gone then. The following is a partial description of my tour in T-33's (high sub-sonic). ----- Sitting in the seat, I noticed several things at once. For starters, my knees were under the instrument panel. I wondered if I would leave them behind in an ejection. We were told that the seat tilted back before ejection, but I wasn't so sure. Secondly, with the seat full down, there was about a half inch between the top of my helmet and the canopy. I had to get used to bending over forward before turning my head around. However, that wasn't the worst of it. The ejection sequence was to raise the handles, and squeeze the triggers. When you raise the handles, the canopy blows. When you squeeze the triggers, the seat goes one quarter of a second later. If the canopy doesn't blow, squeeze the triggers anyway, and a quarter of a second later, the seat will go. For this eventuality, the manufacturer mounted a canopy breaker tool on the back of the seat to knock a hole for the seat to go through. Unfortunately, the tool was located about an inch lower than the top of my head. Nonetheless, people bigger than me have gotten out of the T-33. ----- If you eject under controlled conditions (that is, you have some control over the aircraft -- e.g. you can point the top of the aircraft up), your chances for survival are great. If you have to take what you can get, your chances are diminished. Generally, you want to pull back on the stick to get extra altitude, and lose excess airspeed. Then you want to sit up straight, pull your elbows in, tuck your feet in, and draw your feet and knees together. Then eject. Or, as they used to teach us. "Zoom, Assume, and Boom" -- Would any *sane* person express opinions like this?