Hudson report page 97
The A320 alpha-protection mode incorporates features that can attenuate pilot sidestick pitch inputs. Because of these features, the airplane could not reach the maximum AOA attainable in pitch normal law for the airplane weight and configuration
PJ2,
I think this characteristic of the Airbus is pretty obscure to everyone, except maybe to the Airbus engineering.
Sully would have had a much better flare without that intervention of
additional features built into the system which attenuate pilot sidestick pitch inputs, preventing the airplane from reaching the maximum AOA.
His speed was low, but as proved by AoA + attitude data, there was
ample space for touchdown improvement as requested by the pilot.
There was still a margin of 3.5 degrees to reach alpha max, and probably 3 additional degrees to reach the AoA for a stall.
The features prevented the pilot to flare the airplane as he would have loved.
For a ditching, Airbus recommends a touchdown with approximately 11 degrees of pitch and minimum aircraft vertical speed, but despite the full backstick, the protections did not allow more than 9.5 degrees and the pilots could do nothing to decrease that impressive vertical speed of 750 feet a minute.
I believe Sully would have obtained a better touchdown on his own without the protections interfering with his experience.
Originally Posted by guiones
and have also spoken to several people involved in the (Habsheim) investigation.
Reading your words, I have absolutely no reason to doubt it ...
For the record :
What was "V alfa MAX" ?
What was the corresponding AoA ?
Quotes from the report will be appreciated.