Author Topic: Couple of questions about the F4U  (Read 1224 times)

Offline Rocket

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Couple of questions about the F4U
« on: December 31, 1999, 02:16:00 PM »
Hey all !
  Have a couple of small questions about the F4U.
  Dive brakes.  Doesn't seem implemented yet but what speeds were they good to?  I know on the f4u-1a that 7g was the max limit to pull and 3600 RPM for 30secs was max for the engine in the dive but what airspeed would damage the gear?  I have dropped gear to land and @ 200mph the gear creak and groan.
  Also will we have the true dive brakes that just drop the main gear and leave the tail retracted?
  Accel in a dive:  Overall acceleration of the hawg wasn't near that of the stang but in a steep dive shouldn't the weight of the plane help even this out some?  She is bigger and heavier than the stang I figured in a steep dive that gravity would help assist and make for a quick drop.
  Stalls:  Everything I have read and seen is that she stalled with very little warning.  Will the stall horn be adjusted as the FM is tweaked?

I can't wait till we get some more ground targets to us the full extent of the 1D  

  If anyone has the original specs on the 1D I would like to get a copy if I can or point me in the direction where I can get a copy.  I would like to see the structural limits placed on it and takeoff/landing, turning, climb and dive data.

Thanks
Rocket

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Offline Vermillion

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Couple of questions about the F4U
« Reply #1 on: December 31, 1999, 04:04:00 PM »
From the F4U-1D's Pilot Manual

FLAPS:
The Landing (and manuever) flap control shall not be placed in position for lowering flaps at speeds in excess of 200 knots even though the flaps are protected by an overload mechanism.  If the flap release mechanism is not in operation, the restricted speed with flaps open varies from 130 knots with flaps deflected 50 degrees to 200 knots with flaps deflected 20 degrees.

DIVE BRAKE:
It is not permissible to operate the dive brake controls to extend the gear at more than 260 knots because at higher speeds the dive brakes will not extend fully or lock down.

All I have for yah  

You can order the pilots manual off the internet from a couple of different places.

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Offline Jekyll

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Couple of questions about the F4U
« Reply #2 on: December 31, 1999, 05:51:00 PM »
Verm... I don't know anything about the pilot's manual, but might it possibly have been written, at least in part, by an engineer?

Engineers always seem to include a substantial 'fudge' factor in determining such things as max flap extension speeds etc.

VF-17 for example, disabled the 'auto flap retract' mechanism on their F4U's, because it led to several nasty accidents where a pilot would be on approach, only to find his flaps suddenly retract due to approach speed.

After disabling the mechanism, they never lost a flap from one of their planes due to overspeed extensions.

Source:  'The Jolly Rogers', by Tom Blackburn - p.55

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Offline Rocket

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Couple of questions about the F4U
« Reply #3 on: January 01, 2000, 06:10:00 AM »
Thanks for the info Verm and Jekyll.
@260 kts should = ~290-300mph for the dive brakes then according to engineer stand point? (please note I kts to mph a close guess)
If so then anything above that "could" cause a failure.  Same with the flaps at 20 deg.  

Now I have something to judge by as they tweak the FM.  

Again thanks guys!

Rocket

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Offline Vermillion

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Couple of questions about the F4U
« Reply #4 on: January 01, 2000, 03:32:00 PM »
Not disagreing with you Jekyll  

I was merely posting what the manual said. And yes those speeds are set by engineers, and would inherently have a "safety factor" built into them.

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Vermillion
WB's: (verm--), **MOL**, Men of Leisure,
"Real men fly Radials, Nancy Boys fly Spitfires ;) "