PPRuNe Forums - View Single Post - Max Rate turn vs. Min Radius Turn
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Old 25th Jan 2009, 20:55
  #39 (permalink)  
Islander2
 
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The use of full flap generally only applies to light trainers, as with most high performance machines, the extension of flap will lower the max g limit, generally by about 40%.
idon'tthinkso, you may find it helpful to read previous posts before committing to yet another wrong position:

a) post #9 referred to a 32% reduction in max g limit with flap lowered in a Beech Bonanza; and

b) post #23 linked to the data for the Cessna 150/152 family, showing the Aerobat to have a 42% reduction in max g limit with flap lowered.

So we can reasonably conclude that the extension of flap in maximum performance manoeuvres isn't particularly good advice for either GA aeroplanes or high performance machines!

And, since you're so insistent that we check our books in order to come around to your "it is ever so elementary" yet incorrect assessment, here's a couple for you to go to bed with:

i) Aerodynamics for Naval Aviators by H.H.Hurt, which is the aerodynamics text for US Navy aviators, and which takes seven pages to explain the complexities of maximum performance tactical turning, in the process considering lift limits, strength limits and power limits and

ii) Flightwise (Volume 2 - Aircraft Stability & Control) by Chris Carpenter, who was Head of Aerodynamics at the Royal Air Force College Cranwell in the 1980s, which takes nine pages to deal with the same complexities.

Hardly 'elementary'!

If I could give you a steer (unlikely, I know, from one of 'you boys who haven't flown an aircraft that goes faster than 700kts'), I would point yet again to your incorrect paraphrasing of the relevant formulae. The fact is that turn radius is a function of V^2/tanAoB and turn rate is a function of tanAoB/V. It is mathematically impossible for V=minimum radius to be the same as V=max rate! This is covered more than adequately in the two texts quoted above but, should your preference be for a more academically-rigorous book, I would point you in the direction of Introduction to Flight by John D Anderson.

Last edited by Islander2; 25th Jan 2009 at 21:18.
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