On Thu, 2004-12-16 at 21:40, Terry Neumann wrote: > Many years ago, there was quite a bit of conjecture about the effects > of some control inputs in spin situations which might nullify the > desired effects of others. That is to say, is it possible in some > aircraft for full opposite rudder to be only marginally effective, or > even ineffective if the stick is already full forward at the same > time? There was a lot of talk at the time for the necessity of > correct sequence of control inputs as opposed to the "everything > forward at once" reaction which some had been using - obviously with > good effect in some aircraft, and somewhat less than this in others.
It is now many years since I studied aircraft performance stability and control as part of my aeronautics degree and much water has passed under the bridge (or should that be air over the wings?). However, one thing that was stressed to us was the impossibility of accounting for everything in an aircraft design: there were far to many variables to fully explore the entire performance envelope of any aircraft. Our lecturer (Frank Irving, a glider pilot who did much work in the analysis of gliding btw) related quite a number of anecdotes about 'unusual' performance incidents of aircraft which had previously behaved quite predictably in similar circumstances. The spin accidents reported here have definitely involved some pilot error in some cases, but there does seem to be a suggestion from some of the experts here that it may be prone to some unpredictability in the spin. However, one has to bear in mind that there are questions about the Boeing 737 (several unexplained and inexplicable crashes that suggest something strange is happening in yaw stability in some rare circumstances) and yet we all clamber on board these aircraft quite regularly to fly around Australia (and many other parts of the world). Aviation is not safe, but then, neither is sitting on a chair at home: people will kill and injure themselves while engaged in both pursuits. It is our purpose as glider pilots to minimise the risks and I am firmly of the belief that knowing how to recognise the onset of a spin and recover at both the incipient and fully developed stage is useful risk minimisation. And I will continue to do this in Puchacz - but never (intentionally) at low altitude, in any aircraft! -- Robert Hart [EMAIL PROTECTED] +61 (0)438 385 533 Brisbane, Australia http://www.hart.wattle.id.au _______________________________________________ Aus-soaring mailing list [EMAIL PROTECTED] To check or change subscription details, visit: http://lists.internode.on.net/mailman/listinfo/aus-soaring
