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Old 7th Nov 2016, 05:33
  #335 (permalink)  
Capn Rex Havoc
 
Join Date: Jul 2013
Location: Doomadgee
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MacSheik - Thread creep acknowledged -

Fromt the NTSB report -

2.7.2 High-AOA Envelope Limitations
The airplane’s airspeed in the last 150 feet of the descent was low enough to activate the alpha-protection mode of the airplane’s fly-by-wire envelope protection features. The captain progressively pulled aft on the sidestick as the airplane descended below 100 feet, and he pulled the sidestick to its aft stop in the last 50 feet, indicating that he was attempting to raise the airplane nose to flare and soften the touchdown on the water. The A320 alpha-protection mode incorporates features that can attenuate pilot sidestick pitch inputs. Because of these features, the
97
NTSB Aircraft Accident Report
airplane could not reach the maximum AOA attainable in pitch normal law for the airplane weight and configuration; however, the airplane did provide maximum performance for the weight and configuration at that time.
The Airbus simulation indicated that the captain’s aft sidestick inputs in the last 50 feet of the flight were attenuated, limiting the ANU response of the airplane even though about 3.5° of margin existed between the airplane’s AOA at touchdown (between 13° and 14°) and the maximum AOA for this airplane weight and configuration (17.5°). Airbus’ training curricula does not contain information on the effects of alpha-protection mode features that might affect the airplane’s response to pilot sidestick pitch inputs. The flight envelope protections allowed the captain to pull full aft on the sidestick without the risk of stalling the airplane.

also

However, FDR data indicated that the airplane was below green dot speed and at VLS or slightly less for most of the descent, and
about 15 to 19 knots below VLS during the last 200 feet.
The NTSB concludes that the captain’s difficulty maintaining his intended airspeed during the final approach resulted in high AOAs, which contributed to the difficulties in flaring the airplane, the high descent rate at touchdown, and the fuselage damage. (See additional discussion in section 2.7.1.)
During emergency situations, such as the accident event, pilots experience high levels of stress resulting from high workload, time pressure, and noise. Stress can distract pilots from cockpit duties and result in pilot errors or performance degradation.
I do agree though , that Sully was under a bit more stress than doing a go around in Dubai.
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