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Old 22nd May 2013, 11:35
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bfisk
 
Join Date: Jun 2006
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A common misunderstanding is that LRC gives you max range. It gives you exactly what is says - long range - but not max range.


-Max endurance speed is whatever you get with the lowest fuel flow. It is not affected by wind. On the Speed/Drag curve, this is the lowest point.

-Max range speed is defined by the lowest fuel flow pr. ground distance covered, thus it is dependent on wind. Assuming no wind, then on the Speed/Drag curve, this is the tangent with the lowest angle.

-Long range cruise speed is slightly higher than max range speed, and is a tradeoff, that gives you a (relatively) big speed increase for a (relatively) small range penalty. On the Speed/Drag curve, this will be a bit further up-and-to-the right from the max range; you will see that although the drag increases, the speed also increases by nearly the same amount.



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