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View Full Version : PA-31-350 Navajo Chieftain short field takeoff technique


Wifferdill
22nd Aug 2016, 14:33
Hi folks,

I've recently starter flying right seat in a Chieftain and am disappointed by the short field and obstacle climb performance of this otherwise wonderful beastie.

In an effort to improve matters, I delved in the POH and found Vx (flaps up) to be 84. However, the proper short field takeoff technique is, you're supposed to set 15' flaps, rotate at 76kt and climb at 92kt.

That makes no sense to me. How can the best angle of climb speed with flaps up be SLOWER than with flaps 15?

Anyone have any explanation?

Thanks

W.


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Folks

Vx (flaps up) is 84kias, so I don't understand why obstacle clearance speed is 92kias with flaps 15. In my 20yrs experience, optimal speed has always been inversely proportional to flap extension angle.

Can anybody shed any light on this apparent violation of the laws of aerodynamics as I undestand them?

Matt


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