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Old 9th Nov 2013, 16:40
  #717 (permalink)  
Owain Glyndwr
 
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No way. I think you should read flight controls chapter. .
Vilas,

I think you will find that HN39 understands flight mechanics as well as any writing in these pages.
Although I agree with much of what you write, I think you nevertheless have some things wrong:

Alphaprot is NOT the same as normal law, so when you wrote:

You have to remember that only method of pitch control is changed aircraft doesn't pitch up on its own. During all this aircraft remains in normal law
this was not correct.

I think you are failing to distinguish between angle of attack and pitch. When HN39 writes
With the sidestick left in neutral the airplane will pitch up on its own -

-- in AoA law at alpha=alpha-prot if the speed is greater than Valpha-prot
he is properly relating the flight dynamics. With stick neutral, alphaprot will control the aircraft to a constant AoA, to whit the alphaprot for the applicable Mach Number. It controls AoA; it does NOT control pitch. If the airspeed at this time is greater than that appropriate to 1g at alphaprot then the aircraft will develop a normal acceleration and start to change its flight path. Unless corrected by a change in pitch this will result in a change in AoA. But the system is trying to control to a constant AoA so it must apply a pitch up to compensate. This, I think, is what HN39 is alluding to.
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