vilas
The computers adjust alpha max to stay below Vs1g stall, may be that slight adjustment was enough to cause a descent from 100ft to 50ft.
From the link to the accident report I posted yesterday:
"The first officer informed the captain that the aircraft was reaching 100 feet at 14:45:14. The descent continued to 50 feet 8 seconds later and further to 30-35 feet. Go-around power was added at 14:45:35. The A.320 continued and touched trees at the end of the runway at 14:45:40 with a 14 deg. pitch attitude and engine speed being 83% N1. The plane sank slowly into the forest and a fire broke out."
I would suggest the aircraft sank below 100 feet because they didn't apply any power for 21 seconds, and hence they deliberately flew below 100 feet.
Villas, please explain why you think it was the computers that were not able to keep the aircraft airborne for over 26 seconds with idle power from 100ft at a speed close to the stall.
Hi DW,
@CONF iture - could you please point me to the page/section where you're getting the 2.5deg value from?
May be some confusion with 2.5%?
See FCB 17
"TOLERANCE OF FAC COMPUTED SPEEDS
Due to the data accuracy used to compute the characteristic speeds, and specifically the AOA accuracy, the precision of the computation is specified to be within 2.5 %.
During acceptance flight, the tolerances are as following:
Clean aircraft
Green Dot ±5 kt
VLS ±4 kt
Vαprot ±5 kt
Vαmax ±5 kt
Conf full
VLS ±3 kt
Vαprot ±5 kt
Vαmax ±5 kt"