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Old 5th Aug 2011, 14:48
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A33Zab
 
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@SaturnV:

a33zab, I don't have the answer, but is it possible, without significant turbulence, to get these g accelerations after N1 was just decreased?

2 h 10 00 > 2 h 10 08, N1 decreases from 100 percent to 84 (or 83) percent (in response to a commanded decrease in Mach)

2 h 10 07 > 2 h 10 18, vertical acceleration varies between 0.9 g and 1.6 g.

2 h 10 23 > N1 begins to increase [from 83 percent].
The thrust changes are part of the normal and longitudinal acceleration
experienced by the accelerometers and refelected by the corresponding graphs.

The -normal accell- (Nz) graph is composed of flight control elevator deflections;
THS trim; roll influences; speedbrake and thrust-changes but also environmental disturbences.

For thrust-changes:

If ∆Nz is the difference between the actual Nz and Nz(1g) and the goal is to maintain a 1g flight:
∆Nz = positive above 1g
∆Nz = negative below 1g
At decreasing thrust and a positive ∆Nz this will result in a less ∆Nz to be
compensated for with elevator.
If the ∆Nz is negative (Nz below 1g) this will result in a higher ∆Nz to be compensated for.

Off course it's the other way around with increasing thrust.

Hard to explain when english is not the native, if anyone feels the need to correct and/or make additions he is most welcome.
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