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olirindis
20th Mar 2016, 13:25
G'day all,

Why does the Airbus FBW family reconfigure from ALT LAW to DIRECT LAW when the landing gear is selected down?

Many thanks...

Denti
20th Mar 2016, 17:18
There is no flare law in alternate law, which would make flaring kinda unintuitive. Some newer MSNs do have flare law in alternate law and do not necessarily switch to direct law with gear down...

LlamaFarmer
20th Mar 2016, 23:53
As denti said.
Flare law (in normal law) engages at around 50ft and pitches down so you have to actively pitch up slightly to flare during the landing. Giving it a "conventional" rather than a FBW feel.

In alternate law you lose that mode, so it changes to direct law to give a conventional feel.

Still feels different to a conventional aircraft though.

Check Airman
22nd Mar 2016, 04:35
There is no flare law in alternate law, which would make flaring kinda unintuitive. Some newer MSNs do have flare law in alternate law and do not necessarily switch to direct law with gear down...

Do you have a reference for that? My company just picked up a new plane last week, and I haven't seen any manual revisions.