Originally Posted by
ManaAdaSystem
Why would an aircraft manufacturer recommend keeping the autopilot connected in a situation where the auto flight system clearly is not working as it should?
My 2 cents: Because its bad for sales saying your automatic systems can't handle the tasks they've been designed for.
Now ask yourself: what would the average TRE in your airline say you should do on an RNP approach in IMC with a sudden a/p failure? My bet would be most will say to g/a and ask for another type of approach.
This is the mentality I've found most common during my time with 2 of Europe's largest carriers. So I can clearly see why MANY flight crews would sit and watch the a/p misbehave on an RNP approach and do nothing, even in vmc.
The same many are usually great at quoting details from the fcoms though.