Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!wuarchive!cs.utexas.edu!uwm.edu!bionet!ames!skipper!shafer From: shafer@elxsi.dfrf.nasa.gov (Mary Shafer) Newsgroups: sci.space.shuttle Subject: Re: Why 3 SSME's? Message-ID: Date: 11 Oct 89 15:18:32 GMT References: <538.252A3A3B@mamab.FIDONET.ORG> Sender: news@skipper.dfrf.nasa.gov Organization: NASA Dryden, Edwards, Cal. Lines: 62 In-reply-to: Mike.Pompura@f49.n363.z1.FIDONET.ORG's message of 4 Oct 89 12:12:00 GMT In article <538.252A3A3B@mamab.FIDONET.ORG> Mike.Pompura@f49.n363.z1.FIDONET.ORG (Mike Pompura) writes: >I submitted a proposal to NASA and Rockwell that involved the escape >sequence for a shuttle PES system. >Basically what it was is a method of escape for the astronauts in the >event of a Challenger-type mishap. It was dismissed as not being cost >effective. [Describes a cockpit jettison system with parachutes] > I would be interested in hearing your commentsa on my PES design >proposal. BTW: PES= Parachute Emergency System. As Gene Miya says, if you have a great idea to make the Shuttle better, someone probably already thought of it. The cockpit jettison, with parachutes, was proposed _long_ before the ALT (Approach and Landing Tests) in 1978. I remember Fred Haise and Gordon Fullerton sitting down in the pilots' office here, talking about it. They were picking on Fitz Fulton, because he had an escape hatch in the 747 Shuttle Carrier Aircraft (SCA). Of course, the SCA crew had run back behind the cockpit, fire the shaped charges, climb through a little tunnel, and drop out the bottom of the SCA, but it was an escape hatch. As I recall, much of the difficulty in putting an escape capsule system in the Shuttle is that the Shuttle doesn't have a cockpit "capsule" that is separable from the rest of the vehicle. The F-111, which is the best example of this type of escape system, was designed and built with just such a capsule, making it feasible. (Even it isn't perfect, BTW, but it's probably better than using a regular ejection seat supersonically.) Since the entire Shuttle would have to be rebuilt to do this, it's not practical. Or cost-effective. It's very interesting to me that the public is _so_ much more concerned about things like crew escape systems than are the astronauts. The astronauts know how dangerous the Shuttle is. They know that they'll probably die if there is an accident. Yet they still fight and politick and maneuver for crew assignments and flights, and don't want to wait around for the Shuttle to be perfectly safe. The same is true for test pilots, BTW, and military pilots. And others, as well. On the rare occasions that I've been allowed to fly in a fighter, I do think about what can go wrong, whether I'll be able to eject or not, how reliable ejection seats really are, etc, but I still go fly, because I'm willing to accept the risk. It's worth it to me. But there's risk in everything that we do. How do you deal with risk? What do you think about being an astronaut, knowing the safety record? I'd be at the Cape tomorrow, if they'd let me. Am I the only one? -- Mary Shafer shafer@elxsi.dfrf.nasa.gov ames!elxsi.dfrf.nasa.gov!shafer NASA Ames-Dryden Flight Research Facility, Edwards, CA Of course I don't speak for NASA