Re high altitude icing, engine issues and so on, I see that there is a "
Winter Operations Conference" being hosted by the
Air Canada Pilots Association at the Royal York Hotel in Toronto on these and other topics. The dates are October 7 & 8 with registration on the evening of the 6th. The home website is
here and the agenda is
here.
mm43;
(1) WX radar faulty or crew didn't detect Cb cell(s). Probably former.
First, I acknowledge the "messenger" status and the "perhaps" status of your observations. So it is with respect that I offer some small points.
With regard to the radar serviceability, I don't think there is likely justification for saying, "probably former" (in the quoted passage), as there are no ACARS messages in the mix received indicating a radar failure. From experience, there are definite ECAM and Maintenance messages associated with such a failure. There may no issues at all regarding why the encounter, or there may be "sole causes" as a result of the encounter either as a result of lack of knowledge are pure unavoidability. In short there is nothing we can say about the crew. We simply do not know what went on in the cockpit. I believe we can say in the absence of ACARS messages however, that the radar was working.
As I posted in July, while we cannot state that the engines were flamed out, while we don't have any hard data from the manufacturer, the likelihood of the engines continuing to run with a high angle of incidence is low; hydraulic power from the RAT would be similarly reduced due to the relatively low forward speed as described in the BEA Report. The RAT requires at least 140kts over the blades to generate some hydraulic pressure. Whether ice or high incidence would cause re-start difficulties cannot be stated, nor can we say the APU was running although that would certainly be something the crew may have considered/attempted at some point.
I have earlier posted reasons why I think an aft CG would not be a strong factor in any LOC but could be a contributing factor in abnormal attitudes or post-LOC. In other words, I doubt very much whether an aft CG would in and of itself, even in heavy turbulence or reduced airspeed, (though still well above Vls), would cause a loss of control.
On top of all that the FBW software, when it gave up, gave you back the a/c with control limitations!
The reasons why the autoflight system "gives the pilot the airplane" has been discussed and isn't unusual in transport aircraft. No autopilot is designed or certified to handle an aircraft beyond the accepted limits indicating loss of control. All other transports do the same thing and I think including the statement is incongruous with your excellent analysis. Whether it is causal or not is another matter, mainly for the designers. Suffice it to say that an autopilot capable of recovering an aircraft from unusual attitudes/LOC while managing power and 'g' loads is a long way off; -the best responder is still the human one.
These aren't meant as criticisms of your continuing fine work but observations which I believe must attend any such mapping speculations.
best,
PJ2