Originally Posted by flyingnewbie10
The relatively short length (it is really short and has no escape area) is longer than the one for which the A/C is certified to Land..............
So I would prioritise not reducing thrust (as a factor) and that would be the main (or the real) cause IMHO.
So, OK, there is a prioritisation with an explicit selection criterion. The selection criterion is that a causal factor is prioritised because of what's on a piece of paper.
Isn't that rather a long way from the physical happenings, though? Had all the regulating authorities said the day after the accident "we are recertifying the aircraft only to land on runways longer than 2,400 m LDA", wouldn't the prioritisation criterion have disappeared?
Originally Posted by RWA
With respect, PBL, I did tell you how I prioritise not reducing thrust, by referring to it as the 'primary cause.' By definition, there can only be ONE primary cause.
To me, selecting a specific factor as "primary", and prioritising it, are two ways of saying the same thing. I could as well have asked what your selection criteria are for picking this factor as "primary".
You have partly answered it, I think, in saying
Originally Posted by RWA
But they are not the features of it which deserve the most urgent attention, from the point of view of avoiding any recurrences.
In other words, you choose as "primary" a cause whose prophylaxis deserves the "most urgent attention".
Others seem to think that the factor which deserves the most urgent attention is the state of the runway at Congonhas and the circumstances under which one may land there. This was so even before the accident (I refer to recent comments by marciovp on the regulatory to-and-fro, in which under a certain order the landing with one REV INOP would not have been permitted by the regulatory authority).
So this way of prioritising the causal factors seems to depend highly on one's social beliefs and priorities, not on any objective physical feature of the accident itself. And since people have different social beliefs and priorities, they will choose their "primary" cause differently according to those different beliefs. And then we will have lots of different "primary" causal factors, each one as valid as the next.
But, as you say, your selection of the word "primary" is intended to say that there is just one of them, not that there are lots of equally valid "primary" causes, depending on people's social inclinations. So it looks as if your implicit selection criterion isn't going to fulfil the requirement you make ("by definition") on the notion of "primary cause".
On another matter, concerning the warning mod, the situation is this. TAM has claimed that there is a warning mod incorporated in FWC release H2F3 and they are going to install H2F3. However, one of Airbus's chief safety persons, Yannick Malinge, said before the CIP, if I understand correctly, that the mod to which the Taiwanese report referred had not been implemented because regulatory authorities had reservations about its necessity.
And the H2F3 SB, which describes new features in the release, contains not one word about such a warning. I don't think we are anywhere near a final coherent story about the mod yet.
PBL