It will always puzzle me how nobody put attention to three fully working attitude indicators providing consistantly same indications.
Yes – the pilots had no idea about aircraft systems, where the pitch data is derived from, etc. The stupid inhibit in the stall warner below 60kt was just another factor, but they had lost the plot anyway because the “video game” they were flying, and had been flying for thousands of hours, wasn’t doing what they expected.
Automation can protect from bad pilots but it can’t protect from complete muppets. Well, it clearly can, for thousands of hours, but eventually something really unexpected will happen.
I am sure there have been changes in French pilot training because this is hardly a 3rd World setup in which some of the students write the entire question bank answers on the back of the airway chart (a true story from one UK FTO) 
172driver wrote:
Well, the Airbus ‘logic’ suppresses that warning (or at least did until AF447, don’t know if that’s been changed) below 60kts. IIRC from the accident report, it came on intermittently, they seemed to think they were out of it, when in fact, they were in a deep stall. While CRM certainly had completely broken down on that flight, the Airbus systems logic didn’t help. I venture to say, it was an integral part of the disaster.
I am not arguing against, but any stall warning system has to stop operating at some airspeed, doesn’t it?
any stall warning system has to stop operating at some airspeed, doesn’t it?
Only if you require a purely software solution i.e. working off airdata. That would be the software engineer’s approach
A proper way would be to connect to the landing gear switches, for the inhibit purpose.
However the confusing stall warner was just one hole in the cheese on AF447. They may well have still crashed without that.
So here is a question what is happening to the stall warner in a fully developed spin – assuming you havent pulled the breaker of course ;-)
Airborne_Again wrote:
I am not arguing against, but any stall warning system has to stop operating at some airspeed, doesn’t it?
Sure – wow (weight on wheel) switches, anyone?
Seriously, while there were many holes in the cheese on that dark and stormy night, IMHO that intermittent stall warning was one of the bigger ones.
It’s years since I did spinning, but I don’t remember it on the Zlin242L. (1997). Nor on the C150/152.
Maoraigh wrote:
It’s years since I did spinning, but I don’t remember it on the Zlin242L. (1997). Nor on the C150/152.
I think the answer is thinking about what is happening to each wing and how that interacts with the stall warner. It isnt necessariy quite as you would expect.
Guessing it depends on whether the stall warner is on the inboard or outboard wing, and perhaps on the degree of washout?
I don’t remember it in the C152. i do remember that on the recovery that the stall warner was blaring and it played a role in convincing me to keep pushing despite the windscreen being filled with green stuff. Together with the airspeed indicator it made it amply clear that the angle of attack was srill too high.
