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Old 4th Aug 2019, 16:17
  #28 (permalink)  
sonicbum
 
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Originally Posted by I-NNAV
From the FCOM
FLARE MODE A321 NEO
When passing 100 ft RA, the THS is frozen and the normal flight mode changes to flare mode as the aircraft descends to land. The flare mode is essentially a direct stick-to-elevator law without auto trim, with some damping provided by load factor and pitch rate feedback. The flare law provides full elevator authority.

The flare law has no compensation of the ground effect nor the thrust effect.


FLARE MODE All the others
When the aircraft passes 50 ft RA, the THS is frozen and the normal flight mode changes to flare mode as the aircraft descends to land. Flare mode is essentially a direct stick-to-elevator relationship (with some damping provided by the load factor and the pitch rate feedbacks).

The system memorizes the aircraft's attitude at 50 ft, and it becomes the initial reference for pitch attitude control.

As the aircraft descends through 30 ft, the system begins to reduce the pitch attitude to -2 °nose down over a period of 8 s. Consequently, to flare the aircraft, a gentle nose-up action by the pilot is required.
Interesting, the NEO flare mode looks like the A330, but it is missing the part where it mentions "at 50 ft a slight pitch down order is applied".
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