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Old 9th October 2013 | 15:37
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Airmann
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A320 Flare Mode vs. Ground Mode

There has obviously been a lot written in these forums regarding the flare in an A320, it is something that is a great mystery to those that are new on the bus.

My question is regarding the Flare vs. Ground Mode.

In the FCTM the following two definitions are given
GROUND LAW: The control law is direct law
FLARE LAW: The control law is a pitch demand law

Having looked in the FCOM for a more detailed description of the latter I find that it mentions
1) Pitch trim is frozen at 50 feet RA and this pitch is used as the initial reference for pitch attitude control
2) at 30ft RA The aircraft begins to pitch down to to -2 degrees nose down over 8seconds
3) Flare Mode is "essentialy" a direct stick-to-elevator relationship

The first couple of points are self explanitory. Its the last point that I would like to clarify. Reading the FCTM description of Flare Mode I take from it that the side stick is now commanding a pitch attitude. However, this is not the traditional direct stick-to-elevator relationship that we find in direct law (and consequently in ground Law/Mode). Is this why airbus calls it "essentially" a direct stick-to-elevator, because it isn't but they seem to feel that it is close enough to consider it such?
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