I can't really see where Vne came into it all, perhaps we're considering different kinds of acceleration? Interesting anyway so I'm in. I seem to spend lots of time waiting these last few days - check my posting history and you'll se. *grin*
Of course you will have some kind of design safety margin above Vne where the wings will not instantly decide that they like the slipstream better than the rest of the airframe - but I for one wouldn't count on it. As they indicated in the AVWeb article, metallurgy is a weird and wonderful world and certainly not one to be trusted. Even at 1g above Vne and all bets are off - you might or you might not start to notice parts falling off.
Frantic pullups above Va, not above Vne,is what you need to be careful about (Va is the speed at which the structural damage load factor intersects the accelerated stall curve). What lacks in the depicted flight envelope diagram (it often does) is the fact that loads generated by the airspeed and loads generated by manouevering add up. I e, the structural damage load factor limit will in fact be lower at Vne than it is at Va - you can be safely within the structural limits pulling n g's at Va (actually by definition you can't go above the load factor limit at Va since you should stall first(*)) while pulling n g's at Vne might leave you sans a wing or two. Graphically, the real maximum load factor line slopes down towards Vne.
Unless I'm completely mistaken this is taken into account when certifying gliders, I wonder why it is frequently left out of these diagrams... probably the depicted load limit is for Vne, adding some extra margin. Does anyone know the details? Is this considered for powered A/C certification?
Cheers,
/ft
(*) I think this is for a smooth pull though, momentarily it probably is possible to exceed the load limit even at Va if you yank back on the yoke/stick.
(Proofreading before posting probably would avoid having to edit every post...
)
[ 17 August 2001: Message edited by: ft ]