Path: utzoo!censor!geac!torsqnt!news-server.csri.toronto.edu!bonnie.concordia.ca!ccu.umanitoba.ca!herald.usask.ca!alberta!ubc-cs!uw-beaver!cornell!llenroc!batcomputer!rpi!zaphod.mps.ohio-state.edu!pacific.mps.ohio-state.edu!linac!att!cbnews!cbnews!military From: eachus@aries.mitre.org (Robert I. Eachus) Newsgroups: sci.military Subject: Re: Where was the B-1 ????? Message-ID: <1991Mar14.042151.29594@cbnews.att.com> Date: 14 Mar 91 04:21:51 GMT References: <1991Mar7.012839.29519@cbnews.att.com> Sender: military@cbnews.att.com (william.b.thacker) Organization: The Mitre Corp., Bedford, MA. Lines: 32 Approved: military@att.att.com Full-Name: News Service From: eachus@aries.mitre.org (Robert I. Eachus) In article <1991Mar13.001146.4618@cbnews.att.com> newave!john@uunet.UU.NET (John A. Weeks III) writes: P-38 - First prototype lost while trying to set a speed record. The Lightning also suffered from a problem called "compressability", which never was fixed. The P-38 was required for the war and could not sit out waiting for a relatively minor problem to be sorted out. Not quite... The compressability problem was "simply" air around the control surfaces reaching transonic speeds during a dive. To pull the control surfaces into an "incompressable" airflow was (and even with modern controls is) impossible. The flow is incompressable because it would have to go supersonic to get out of the way. The "right" design correction is to make sure that the air always has someplace to go, but it wasn't until relatively recently that airframe designs could be verified not to need dive brakes. There were two solutions: 1) do an outside loop--the pilot couldn't pull up, but he could go through the vertical and out the other side. 2) Add "dive brakes" to slow the plane out of the transonic regime. These were, I think, added in the P38-J model, but they may have come earlier. As far as I know the only problem never fixed in the P-38 was that the cockpit was unheated and unpressurized. -- Robert I. Eachus