Originally Posted by
BOAC
As I said, narrow focus. My suggestion was to limit autotrim, full stop.
Why? What good would it do?
I'd dispute the "narrow focus", the scenarios are completely different and completely unrelated - other than the point that the crews involved didn't keep an eye on their trim status when they should have done so.
In fact the two B737 incidents began with failing to monitor airspeed and thrust settings on approach - the trim situation was an afterthought. I'm pretty sure I remember reading that SOP in a B737 go-around scenario from autoflight involves adjusting the trim to a setting commeasurate with go-around, because approach trim configuration isn't going to work there.
AF447 wasn't caused by the automatic trim, and unlike the B737 incidents, the trim was effectively set by the pilot's commands - not autoflight.
Those are pretty different scenarios no matter which way you slice it.