bearfoil, quote:
"If the decision had been made to turn around, why not a maximum rate turn to port off the airway at some point past LKP ??"
We hope soon to have an indication from the CVR of the point at which this flight ceased to be "ops-normal" from the pilots' viewpoint. Not sure what you mean by a "maximum-rate turn", but I cannot think of any circumstance where a crew already experiencing severe turbulence in a Cb or line squall would attempt to turn back. In heavy precipitation, the radar tends to be fairly useless until you come through it. The time to do a big turn is well before entry.
Once you are in it, you are going to avoid anything but the most gentle of turns. Prior to that, you can try to plan a zig-zag course between cells, staying clear of the worst stuff, but there's always the chance of a weaker/smaller cell eclipsing the big, nasty bugger beyond.
Doubt you would find any pilot who has actually decided to abandon a passage across the ITF (sorry, ITCZ) for lack of alleyways. In any case, the analysis suggests that this crew would have been anticipating a routine one. And evidence suggests that they had not deemed it necessary to secure the cabin in advance of this event.
gums and Machinbird,
As you both tend towards the deep-stall scenario, maybe resulting from a sudden pitch-up, wouldn't it be interesting to see how far the high-altitude, low-speed part of the envelope was explored during certification?