Not wanting to fly in IMC

No, the recorder specifically recorded "watch this" and then the panic'd sound of the pilot realizing he did a bad thing. We had to study the accident when I was in school.
 
I think you guys are thinking of two different accidents. I have a feeling Kent speaks of the AA headed to the Dominican republic shortly after 911 from JFK. It came apart trying to recover from wake turbulence. Full plane. No time to be demonstrating Va.
 
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n20junkie said:
You might wana look into what Va affects, because the rudder isn't factored into Va.
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Some think Va is a magical airspeed that you can do no dammage. It is only valid at max gross (under gross will stress the engine mounting and other components from faster than normal acceleration) and it is only for the wings. NOT RUDDER!!
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You are partially correct. Va is not taught very well at the private and even commercial pilot level. CFI is a little better.

You are correct Va does not affect the Rudder, at least in aerodyanmic terms. In legal terms it may.

You are partially incorrect that damage can occur below Va, however FAR 23.441 requires that the vertical structure be adequate to support a full deflection up to Va. But not all aircraft are certified to FAR 23 standards.

You are are somewhat incorrect about Va at lower than gross weights. By the true definition of Va, Va simple is less at lower gross weights. I haven't confirmed it but I suspect most small single engine manufactures simply list Va at the minimum flying weight which would be the safest way to do it. Larger aircraft actually list Va at different weights.

The true definition of Va is the speed at which the aircraft will stall before it will pull more G's than the aircraft is designed for. Note there is also a positive G and negative G Va speed. The stall unloads the wing and thus prevents pulling any more G's.

Brian
CFIIG/ASEL
Former Technical Designer for the Thunder Mustang.
 
brcase said:
You are are somewhat incorrect about Va at lower than gross weights. By the true definition of Va, Va simple is less at lower gross weights. I haven't confirmed it but I suspect most small single engine manufactures simply list Va at the minimum flying weight which would be the safest way to do it. Larger aircraft actually list Va at different weights.
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Actually, the Va listed for the typical training aircraft is usually given at max gross (not minimum flying weight) on the placard and (sometimes) at lower weights in the POH. Therefore, it's up to the pilot to lower that value based on the percentage under max gross that they are at the time. In other words, you should be DECREASING that speed as the flight progresses and fuel is burned off!

An interesting article on it is http://www.principalair.ca/article-va.htm. He doesn't go into the rudder issue, but presents some other interesting tidbits.
 
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