Newsgroups: sci.aeronautics.airliners Path: news From: weiss@ada.SEAS.UCLA.EDU (Michael Weiss) Subject: Re: hydraulic problems with DC-10's?? X-Submission-Date: 8 Dec 92 05:27:28 GMT References: Message-ID: Approved: kls@ohare.Chicago.COM Organization: SEASnet, University of California, Los Angeles X-Submission-Message-Id: <8852@lee.SEAS.UCLA.EDU> Sender: kls@ohare.Chicago.COM Date: 08 Dec 92 15:51:09 PST In article drinkard@bcstec.ca.boeing.com (Terrell D. Drinkard) writes: >In article weiss@turing.SEAS.UCLA.EDU (Michael Weiss) writes: >>I am referring to the unbalance of WEIGHT, not THRUST. >It doesn't matter, the loss of weight on that wing was actually a >short-term plus in that incident (effectively generated a right-hand >(positive) roll moment to help counter the loss of lift on the left wing). I'll reply to this below. >>Which doesn't disprove my theory. As it is, though, the loss of the slats >>(which, according to all my aero classes, only lowers the stall speed but does >>NOT increase the coefficient of lift!) was enough to stall the wing >It isn't possible to lower the stall >speed without improving the coefficient of lift (assuming constant weight, >air density, and wing area). Actually, assuming constant wing GEOMETRY, which includes, besides area, shape as well. Slats change the geometry. Their benefit is a reduction of the stall speed, through delay of separation. I believe the way that it does this is by directing a stream of air along the upper surface of the wing. In any case, my point is that there would have been a severe weight unbalance between the wings, and I have doubts that it could have been countered by the ailerons. The whole reason that there was a negative roll moment was that the left wing STALLED, not that it lost lift directly from the retracting slats. I'm still not convinced that even WITH the slats extended it could have been prevented. -- \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | / - Michael weiss@seas.ucla.edu | School of Engineering & Applied Science - - Weiss izzydp5@oac.ucla.edu | University of California, Los Angeles - / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | \