Path: utzoo!attcan!uunet!ginosko!uakari.primate.wisc.edu!dogie.macc.wisc.edu!gatech!amdcad!military From: cognos!sunray!roberts@uunet.uu.net Newsgroups: sci.military Subject: Re: XB-70 Message-ID: <27533@amdcad.AMD.COM> Date: 28 Sep 89 07:13:08 GMT References: <27497@amdcad.AMD.COM> Sender: cdr@amdcad.AMD.COM Lines: 46 Approved: military@amdcad.amd.com From: cognos!sunray!roberts@uunet.uu.net Sorry, still more on the crash of the XB-70 prototype at Edwards. [But providing some additional details , so I'm posting it. --CDR] Following up to several postings on the cause of the crash: I am fairly certain that the determined reason for the crash was pilot error on the part of the pilot of the F-104. His aircraft was caught in the huge vortices generated in the area above and behind the six side-by-side jet exhausts and slammed into one of the vertical stabs. (Pilot error is a somewhat brutal assessment, because no aircraft before or since the XB-70 has had the capability of generating such enormous forces in such a restricted volume of air). Most of the vertical stab was sheared off, and the XB-70 went into a flat spin from which it was unable to recover. There is a fair amount of film footage of the accident available which shows all of this. When the crew tried to eject, the ejection sequencing failed. Crew seats deployed forward from the individual ejection pods, on little rails. The planned ejection sequence moved the seats back into the pods, closed the pod doors, blew the aircraft skin hatches, and ejected the pods (hopefully clear of the enormous vertical and horizontal surfaces). The XB-70's flat spin resulted in a very large centripetal force acting towards the nose of the aircraft, based on the considerable distance of the cockpit forward of the centre of rotation. This force was apparently larger than the force supplied for stage one of the ejection sequence, moving the seats back into the pods. (Only two crew were on board, in the left and right front seats.) The crew member who did eject apparently managed to horse his seat into the pod manually, by brute strength, and suffered severe injury in the process. As I recall, the other crew member rode the aircraft into the ground, because I think the ejection sequence was locked by the failure of stage one. The point is moot, ejecting with the seat deployed forward of the ejection pod would not be survivable; in fact, it is unlikely that the pod would clear the airframe, and the forces involved in a Mach-3 capable system are extremely destructive. Robert_S -- | _ \ / _ \ / __| Robert Stanley UUCP: uunet!mitel!sce!cognos!roberts | |_> || |_| |\__ \ INET: roberts%cognos.uucp@uunet.uu.net |_| |_\|_| |_||___/ Voice: (613)738-1338 x6115 Cognos Inc., 3755 Riverside Drive, PO Box 9707, Ottawa, Ont K1G 3Z4, Canada