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Old 16th November 2007 | 12:02
  #40 (permalink)  
Islander2
 
Joined: Jan 2006
Posts: 423
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From: An island somewhere
H Peacock wrote:
Not true. A slow aeroplane/helo does not need lots of 'g' to achieve high turn-rates, and therefore doesn't suffer from a big increase in induced drag.
Have another look at my post: it doesn't say that, does it? What it says is: "a high rate of turn will result in loss of airspeed due to inertia and/or increased induced drag (the amounts of each depending on how the turn is achieved)"

Also:
You gain IAS turning in to the wind, lose it turning downwind - is that what you're saying?
Categorically not, 'cos it isn't necessarily true! What I am saying is: 1) that the impact on IAS is identical whether you're turning upwind or downwind for the same pre-turn IAS, and 2) that whether or not the turn results in an increase or decrease in IAS is dependant solely on whether the IAS is initially greater or less than zero, and is nothing to do with whether the turn is upwind or downwind. If the pre-turn IAS is positive ahead of a very rapid turn, you'll temporarily lose an equal amount of airspeed whether turning downwind or upwind; if it's negative (obviously not a usual fixed wing scenario, but certainly one for Harrier pilots), you'll temporarily gain an equal amount.

Edited to add an intepretation note: all the above assumes a steady wind.

Last edited by Islander2; 16th November 2007 at 21:41.
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