Originally Posted by
infrequentflyer789
The issue is that when IAS < 60kts Alpha = NaN (or NCD or whatever invalid indication). This happens before the SW computer.
So, is NaN > X or not ? That is the issue the SW logic has to decide.
You can't just fix the SW logic, in any meaningful way. The input data simply isn't there in this scenario.
Hmm, I'm afraid you might be quite on the mark with this objection. This could very well be the reason why they implemented this less than ideal solution.
Circumnavigating the ADIRU in certain instances while going through it normally might open up new cans. (Additonal mini ADR required with possible discrepancies to main ADR's requiring redundancies and another Error Handling logic...)
From a boolean perspective a solution seems possible and even not too complicated but it might indeed conflict with their basic system design necessitating less than ideal workarounds causing other trouble.
Will be interesting to see if, when and how they can fix this.
I seem to remember that Boeing does have a similar logic of suppressing the warning if the speeds are too low. Anyone any idea if they are working on that topic as well?
Do they also calculate SW behind the ADR modules (which normally makes a lot of sense as you would otherwise need an additional mini ADR unit to convert the Raw data in a usable format just for the Stall Warning alone).