Hi,
DozyWannabe:
the aircraft's systems told them that they were approaching stall
What type of Stall?
and continued to warn them as they went into the stall regime itself.
SW was presented several times erratically, not adequately processed by the System.
It warned them that they were in Alternate Law 2 without protections.
Ok
The ADI told them that they were too nose-high
Ok
the speed indications (when they came back) indicated they were too slow
Faulted at critical moments
and the altimeter was unwinding at an alarming rate
After FUBAR "threshold"
IMO, the A/C (it's man machine interface) could (may be, should):
1) Provide an
"immediate"* information (aural, whatever) to inform origin of trigger problem (actually a "frequent" and recurrent problem). It would have helped.
2) Protect* (limiting to REC MAX FL) from zoom climbing to the "corner" entering "the coffin"
.It could have helped.
3) Provide* information on "dangerous trend" like AoA increasing at such rate. It could have (redundantly) alerted PM on PF "fatal" persistent NU.
4) Better Stall (
characteristics) indication. Technically feasible. It could have "helped".
5) More elaborated Aural and Visual information to help "HF aspects" during "crisis". It could have increased their chances reducing confusion, stress, etc.
In this specific point we may mention: Antoine de Saint Exupéry's "It seems that perfection is reached not when there is nothing left to add, but when there is nothing left to take away"
Probably something that can be applied during extreme conditions in many designs.
Mac
PS
Man machine interface designers would have an opportunity after the results of the HF study of AF447.
(*) Cost: "near zero"