Question about Flaps Deployed at High Speeds..

[dtango]

Did a few more flight tests of the F6F-5 myself with 25% fuel.

I agree with F4UDOA - if we are using HT's definition of not being able to hold VSI=0 as a stall then I can't explain why the F6F-5 seems to be stalling around 101-102 TAS mph around 300 ft alt.  This seems a little high for the stall speed to me.

Here are a couple of things I found of interest however:

(1) Using alt-x and speed set at 100 mph I keep getting the F6F-5 speed with VSI=0 holding at 101-102 TAS mph at 100-300 ft alt.  Is the film viewer speed just a hair off?

(2) I can maintain flight with the VSI needle just a hair under 0 (~.5-1 fps decent) and if I use the definition of a stall when I have a departure of control (wing tip over etc.) then I can maintain flight to 93-96mph TAS at 100-200 ft alt before I have departure of control.  (I used this definition in my earlier tests).

Maybe what we are seeing in the AH F6F-5 is the modelling of the differences in lift distribution across the wing?  CL figures for a wing is the average of the lift distribution across the wing.  In reality the 3D lift distribution across a wing is not constant but varies from station to station so you may actually have local stalls at different regions on the wing but not lose control of the aircraft.

Of course this is pure conjecture on my part on HTC FM's.  I'd be interested if HT or Pyro has any further comment on this.

Tango, XO
412th FS Braunco Mustangs

[frank3]

flap-deployement at high speed? that isnt even possible

[F4UDOA]

Punt,

HT, don't end the dialog now.

It's like having a conversation with someone on a cell phone and the phone cuts out.

Just say something like "I'll look into it" or "Bugger off" or something.


Dtango,

Thanks for running test. Notice one more thing. The stall really doesn't change with fuel load. With 25% fuel The F6F is getting close to 11,000LBS. That's 1,500LBS under takeoff weight and the stall is about the same. Climb rate does increase proportionate to weight but stall does not. Very interesting.

I want to shoot off all ammo and see what the stall is.