BEA Rapport Final
Quote from noske:
"Well, that's the risk you take with an unofficial publication. That document was probably derived from the BEA PDF, and transcribing those DFDR printouts must have been especially error-prone. I'd say that the evidence offered by CONF iture (the magnified scans, and the values as they appear in the narrative) is sufficiently convincing."
Yes, I agree with all of that. It is ironic, however, that the RA figure of 24 ft at TGEN 334 in the HTML version of Tome 2 is more plausible than the 34 ft figure in the PDF copy of the BEA report. The Karsenty video rules out any inference that the a/c might have climbed 10 ft in the last second.
Whichever of the two figures is correct, students of the report might expect that its final edition would have corrected an unnecessary anomaly that undermines the authority of the whole document. If that and other less imperative amendments were done, it is unfortunate that the BEA has not made the amended document accessible via their website.
In public transport, the Habsheim accident has unique aspects and complexities, and continues to provide a basis for the study of a broad range of aeronautics. In recent years, the BEA has published several very informative papers relating to flight safety matters in general. Its valuable contributions to the subject are somewhat undermined by the continuing deficiencies of the Habsheim document.
Hi gums,
Just a reminder to you and others that, in AF447, Pitch Alternate Law allowed the THS to continue auto-trimming to full nose-up trim. At Habsheim, starting with Pitch Normal law, the THS auto-trimming was disarmed first (briefly) by the premature, 2-second engagement of Flare mode at TGEN 313 (t -21) - triggered by flying over trees; and, secondly, when Flare mode was entered again at TGEN 317 (t -17). Finally, it remained disarmed when Alpha Protection mode took over from Flare mode at TGEN 330 (t -4). Earlier, in fact, it had had no need to trim between TGEN 306 (t -28) and t -21. So, to sum up, it remained at U04 (4 degrees nose-up trim) for about the last half a minute of flight. Full deflection in the nose-up trim sense is 13 degrees.
Last edited by Chris Scott; 14th Mar 2014 at 16:03.
Reason: Last paragraph added. Penultimate paragraph improved.