Vne, Va and lift?

On Fri, 11 Sep 2009 01:50:08 -0700 (PDT), "Flaps_50!"
wrote:

On Sep 7, 4:10*am, a wrote:
On Sep 5, 10:20*pm, "Flaps_50!" wrote:



Ever watch that video of the Air Tanker C-130 snap it's wings after
dropping retardant on a fire? Imagine pulling out of a dive (while
banking) in a valley and then within a second losing 10,000 lbs of
cargo... when the weight is reduced, load factor goes up for a given
value of lift. In the case of the C-130 there may have been other
factors such as metal fatigue but the increased load was the primary
cause.

=======
I watched the video -- seems to me what happened is aoa was
appropriate for the load, when the load was lost the sudden excess
lift over weight acted pretty much the same *as if the pilot suddenly
yanked the yoke fully aft, but will let others more skilled make their
points.


this diagnosis didnt make sense to me. how could an aircraft that has
just shed it's load fail? with the shedding of the load the airframe
gets relatively stronger.
the locheed reports indicate that the aircraft had an undetected crack
in the root of the mainspar that had grown to such an extent that the
structure was compromised. the events that you see on the video are
coincidental and not the cause of the crash.
the crack grew to the point that it broke up in flight. that was the
cause.
Stealth Pilot