Clandestino;
Thank you for your responses to my comments.
Quote:
Originally Posted by PJ2
The "5deg pitch above FL100" is misleading and wrong
It is not wrong and it is not obligatory.
In reverse order... First, we're arguing the same point but for different reasons. I have always argued that the initial memory items (
regarding the 5deg pitch attitude above FL100) were not obligatory but you continue to misunderstand the point of all my posts on the topic. The drill was indeed viewed as obligatory as far as the BEA was concerned (in their press conference) and as far as many on this board were/are concerned.
Note -
edited to clarify the notion of "obligatory" and the execution of this drill:
The drill is obligatory in the sense that there is an abnormality and there are memory items associated with the abnormality. In this case, the first memory items are bypassed because they don't apply, because the airplane is above circuit altitude and above MSA. The memory item is, "level off and troubleshoot". It is not obligatory to pitch up to 5deg. That has always been my argument.
The point of my early and ongoing interventions was to provide reason to re-consider the assumed-obligatory nature of the drill and (
see above) to question or at least think about why anyone would pitch a transport up while in stable cruise. The FCTM and various Airbus documents, some of which I have posted links to, indicate that automatically pitching up is
not the correct response.
For the longest time, no one here agreed with that view and kept reaffirming that the correct response in all circumstances was first, pitch up, then re-stabilize the airplane.
The fact that a 5deg pitch isn't as harmful as a 15deg pitch-up is beside the point: Why pitch-up at all when in cruise flight just because the pilot considers that there is "immediate risk to the safety of the flight"? Where is the "immediate risk"? In my view, there is apparently far greater risk in destabilizing the airplane in cruise flight than in keeping it level, for troubleshooting. Thirty-odd other crews seem to have agreed with this view.
It is in this manner that I consider the UAS drill "wrong"...perhaps too strong a word, but the drill is, clearly, poorly-written. While others may not think so, I think that that requires an examination.
The memory drill's first question is, "is the safety of the flight at risk?" That is a crew decision which directs their response one way or another.
That is an important decision and I submit that the question, "is the flight at immediate risk" is more subjective than a decision based upon, say, flight phase. I'm trying to consider a way of making the response more clear. I considered flight phase to be a natural way to do this and gave some thought to a re-designed drill as per a recent post.
You will agree will you not, that loss of airspeed indications during the flight phase AF447 was in, is not nearly as serious as losing airspeed information during the low-altitude takeoff-initial climb phase? The intent of the pitch attitudes stated in the memorized portion of the drill was to provide immediate, safe numbers for such failure in a flight phase where looking up the numbers isn't possible. In cruise, the airplane is already established and in a stable flight phase and the crew has time to respond differently, as per the last memorized item, "when above circuit altitude or MSA, level off and troubleshoot".
Regardless, the main point I have always made and which you continue to miss is,
Why destabilize a transport aircraft in cruise flight when a better course of action is to keep the pitch and power settings which existed prior to the failure? I made the mistake of stating that a pitch up to 5deg would lead to essentially the same result as AF447 and I was wrong and have corrected and stated that view a number of times. Please, move beyond my original mistake and argue if you will, from the present point being made.