Byron Brandon Ward wrote:

If you allow the V tail to fly 15 degrees nose down
for 26 seconds you will exceed the the cruise speed by
130 kts. If you hit a gust above a certain verticle
velocity, at that point, the unmodified airplane will
probably break up. You could easily be reading your
approach plate for only 26 seconds and not notice
the speed build up. The tail and wings were always
the first parts found on the debre path.

I don't dispute your point in general, but I think 15 degrees nose down is
*lot*. For instance, if your approach speed is 80 mph and you assume
sine theta is about theta (I don't have a calculator here), 15 degrees
is about 1/4 rad so thats 20mph down or a little over 1500 fpm descent.
A standard approach then would be 300 fpm. That's a big difference. Also
not looking at the gauges or outside for 26 seconds is quite a while.

Byron

Not my point Byron. It's Dr. Roberts. Think of 26 seconds
as worst case. Many mess up in ten seconds by encountering a
severe gust. Yes it does seem like a lot. It's a theory
to explain the extrodinary number of V tail and 210 in flight 
break up accidents as compared to the rest of the fleet.

An IFR 182 is a much safer place to be as it builds speed
much more slowly due to all the drag. Might not get to flutter
speed if you pointed it stright down :-)

Not all accidents happened on final. I would guess short final
with the gear out and flaps the opposite could occure. You could
get too slow and stall.
  
Paul Lamar
 
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