Met synopsis
Tim Vasquez's report, whilst being fairly technical, concludes well. We don't at the moment know the ADD status of AF447 and what if any MEL's the a/c dispatched under. So called ETOP's dispatch with single radar, IRS fault or a prim/sec problem is not unfeasable. Comment was made that many crews frequently attempt to fly over weather; in an almost max weighted 330 or even 340, this would be folly. Pilots who have little experience of other types may attempt this manoeuvre but for those with L1011/747 classic/DC10 time, that would be a rare judgement call. The digi radar on the Bus requires more analysis and very carefull gain and tilt management than earlier analogue types. The buffet thresholds at close to or even at, max recommended or above optimum altitude levels are also narrower than non FBW types. For these reasons, lateral wx deviation, even by track displacements of over 100nm are not uncommon within the ICZ that I operate through. It appears through Tim's track analysis of 447, that no significant wx avoidance was applied. As an after thought, wrt CRM and crew rest issues, were the senior crew resting at the time of the 'event'? What was the crew pilot compliment/experience? was this a training sector for either the capt or F/O?
As a senior check and trainer on the 330 and 340, I always, without exception employ two cardinal rules.
. Rough air speed protocols versus altitude limitations must be applied early on in the piece. If the air is rough,(med/light, med turb and above), select M.78 without delay. "Chunking down" of mach to finally achieve target .78 is not recommended.
. Early wx deviation and crew lockdown is key to successfull wx damage avoidance. Never attempt to outclimb weather. Cherry picking the weaker cells and risking penetration of invisible gust regions, again is folly. Keep the big picture in mind, take the additional fuel at flight planning and large track mile deviations.
The above is intended to compliment Tim's fine piece and in no way wishes to undermine the severity of the event and its tragic outcome. RIP pax and fellow crew.
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