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is Vmca mean stall speed?

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is Vmca mean stall speed?

Old 23rd Dec 2013, 01:50
  #21 (permalink)  
 
Join Date: May 2013
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some kind soul bent the ground adjustable trim tab on a Cessna 150 of all things.
a mate was PIC and we went out for a fly to a local restorer of Tiger Moths.
on the flight back my mate asked me to put my foot on the right rudder so that he could give his leg a rest.
at my questioning it eventuated that he had lost muscle control of his right leg and had quietly poked his left foot on the right rudder. when this eventually also gave out he had both feet on the right rudder and both his legs had lost muscle control.
my right leg lasted a few minutes then I had both legs on the right rudder and finally we flew the aircraft with both of us with both legs pressed on the right rudder.
all because the little ground adjustable trim tab on the rudder had been bent to about twice its angle.

so Vmca is one thing. the elephant here is the question of just how long you could actually push hard on the rudder. the need doesnt diminish but the ability of human muscles to push sure diminishes.
...I'll go back to sleep....
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Old 23rd Dec 2013, 02:20
  #22 (permalink)  
 
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Falcon 20 training IWas required to Maintain altitude at max power but knowing what would happen, reduced power on the good engine and maintained control.
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Old 23rd Dec 2013, 02:41
  #23 (permalink)  
 
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Of course we descended but didn't go below VMC so maintained control. The drill was of course was to demonstrate getting beLow VMC.
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Old 23rd Dec 2013, 07:37
  #24 (permalink)  
 
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Originally Posted by Old Fella View Post
At no time during my B707 experience was practice double asymmetric flight conducted, either in the aircraft or in the simulator.
Really? It's a required semi-annual event at a US airline. I've held commands on 2 4engine types and flight on 2 engines (on the same side) is a required item for every left seat checkride. I've done it in both the airplane and the simulator, and while I can understand not doing it in the airplane, I can't imagine why you'd avoid it in the sim.

Maybe I've misunderstood you.
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Old 23rd Dec 2013, 12:03
  #25 (permalink)  
 
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Double asymmetric

A Squared, my omission. What I failed to include in my post was Vmca. i.e. we never practiced double asymmetric flight in the B707 in the aircraft or in the simulator in relation to demonstrating Vmca. Given that you fly the C130 (L382) I can understand that you would look at double asymmetric in the Simulator, not so sure that I would agree with practicing the configuration in the aircraft. I know we did not practice it in the C130 other than in the Simulator. I assume you do not practice it in the aircraft at low altitude or at a speed anywhere near Vmca2. I also trust that in your aircraft practice you do not shut down the engines but come back to, or slightly above, flight idle.
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Old 23rd Dec 2013, 14:57
  #26 (permalink)  
 
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Old fella, thanks. Makes more sense when you include "demonstrate VMCA" You are correct, we do not shut down engines, rather use a throttle setting close to flight idle which simulates a feathered engine. No, we do not get anywhere near VMCA2, and the simulation ends at MDA. I have seen 2 engine VMCA, but that was in the sim on a scenario with losing a second engine on a 3 engine ferry takeoff.
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Old 23rd Dec 2013, 22:47
  #27 (permalink)  
 
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Glider Overshoots P.S.

It was more than 60 years ago, when I did my gliding, as related above, as accurately as I can recall. (See # 13. # 15 or #19 above.)

Time has moved on and the French National Gliding Centre at Montaigne Noire, near Revel seems to have gone too.




The lessons that I learned there, may have been of help when I was having to trade height for speed following one propeller auto coarsening on overshoot at weather minima. To have attempted to retain all height might have led to a stall. My speed got awfully slow.

Last edited by Linktrained; 23rd Dec 2013 at 22:57.
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