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Old 9th Apr 2004, 17:43
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willbav8r
 
Join Date: Oct 1999
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Ground effect = more lift.

Vmc = loss of directional control due OEI and operating engine at max power (10 factors of Vmc of which out of ground effect is one).

So here we are in ground effect, left engine goes quiet. We have just taken off from a soft strip, so we rotated 5 knots over red line (silly, but I'm being hypothetical). Full power is being issued by the co-operating engine. Because we are in ground effect with a negligible ROC, we have high AOA (because it is warm and we have density alt of 3,000). Eventually if we pitched for Vmc, because of ground effect (which increases lift and decreases stall speeds) we would be faced with a lower Vmc speed?

Incorrect methinks, because, as we approach Vmc, the increased lift on the wing with the co-operating engine is going to roll faster (loss of directional control)?

But we have reduced the stall speed because of ground effect, ergo we might have a lower Vmc. So does this mean that we could stall before reaching Vmc? Slightly worse than wandering to the left.....I can tell you that stalling with OEI and one at full chat would not make me a happy bunny.......

Intersting stuff.

Last edited by willbav8r; 9th Apr 2004 at 17:54.
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