Originally Posted by
Centaurus
Suggest refer to original post as above. Thread drift on to QF bashing seems to have got more attention than the hard landing at Melbourne..
While there are enlightened operators who encourage their crews to keep their hand in by switching off technically non-essential automatics for the task in hand, they are probably in the minority. Conversely there are those operators who actively discourage any sort of hand flying and are known to impose severe penalties for those who genuinely would like to keep up manual flying skills. It seems to be a culture thing.
In the case of the incident involving the hard landing by the A330 at Melbourne - the subject of the first post - it seems evident that the pilot left the auto throttles to do their own thing while he (or "they" the political correctness term beloved by ATSB but not by overseas authorities) thrashed around his control stick to such an great extent that he assaulted the runway with the A330. The A330 lost the battle with the runway as evidenced by the landing gear severe damage.
I would have thought it would be common sense for a pilot when switching to manual flying on final approach to simultaneously turn off the auto-throttle so he is completely in the loop so to speak, rather than half-automatics and half manual flying.
Maybe that is inadvisable in the Airbus series because of various PFM inputs by computers that are in place to minimise pilot incompetency?
Not having flown an Airbus I wouldn't have a clue. I do know that Boeing advise (for example) in their 737 FTCM: " To simplify thrust setting procedures, autothrottle use is recommended during takeoff and climb in either automatic or manual flight. During all other phases of flight, autothrottle use is recommended only when the autopilot is engaged."
That said, it is common practice by some airline pilots to conveniently disregard that Boeing advice and leave the autothrottle engaged (when Boeing advise it should be switched off) because of lack of confidence in their own ability to handle the aircraft manually with the autothrottle switched off.
You are right. Airbus is different. It is very rare to turn the autothrust off unless it is for manual practice. Most approach and landings are done with autothrust on.
It is a very good system in the Airbus, it has a few catches just like the Boeing, however if you're aware of its limitations and use appropriate automation for the task - then it works well.
Pitching +/- 2.5 like this pilot did will cause the autothrust to exacerbate the pilot induced occilations. the secret to the bus is 'small' control inputs and maintain the body angle from 200 feet.