PPRuNe Forums - View Single Post - What causes the slight "pause" at around 10 degrees during rotation in the 767 and 73
Old 23rd Feb 2013, 09:17
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Tee Emm
 
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What causes the slight "pause" at around 10 degrees during rotation in the 767 and 73

Appreciate any factual technical information on why does the 767 and 737 have a "pause" around 8-10 degrees nose up as the aircraft is rotated for take off? Do any of the FCOM or FCTM mention the reason for the pause?

One explanation is it happens as the tail goes down into ground effect and causes a stick force change. That theory is shot when one considers these aircraft have hydraulic controls with artificial feel. Another theory is the relative positions of the C of G and Centre of Pressure change during rotation, causing a nose down change of trim.

The third answer is that the "pause" is designed into these aircraft to minimise tail strike if the rotation is too fast?
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