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Throttle/Pitch not coordinate well when initiating FLCH (found out why)


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Just tried the SP1 with E190, I noticed the Throttle are changing way too fast than pitch, when initiating an FLCH climb or descend.

It pushes airspeed about 15kts higher than command speed when starting a climb, or 20kts lower when starting descent.

After a while, the pitch follow up and eliminate the difference, keep on speed throughout the remining FLCH phase.


EDIT: I just noticed it's due to CG error, see below.

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It's normal behaviour for autothrottles to behave this way, to some extent, with the throttle leading altitude change. Real autothrottles are carefully designed to achieve the most efficient performance combined with fuel economy. Sometimes their action can appear counter intuitive, but it will have been tested very thoroughly.

When manually flying a jet aircraft, it is usual to open the throttle/s for a climb, and progressively apply back pressure on the yoke. The speed will fluctuate slightly, and throttle adjustments will be needed. The actual speed variation may be less than with the autothrottle, but the process may use more fuel. For a manual descent at the same airspeed it would be common to throttle back and let speed start to decline slightly before lowering the nose. But not usually as much as a 20 kt reduction.

I can't say if the amount of throttle lead in the simulation is accurate for the E190, but 15 to 20 kts looks slightly high.

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I just noticed the "Normal" CG for this add-on seems is 50%MAC while the real aircaft would be 25%, The behaivor I saw is bacause my 3rd-part loading program load the CG to about30%, that make the airplane very nose-heavy.

with normal load, it's much better, about +7 and -5, I would say it's manageable.

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