Originally Posted by
Machinbird
To be sure we are communicating effectively, look at figure 5 ... That is what I am calling a counter-pointer altimeter.
Sure - if you look at what I wrote quickly, you'll see I mentioned
"...the optimum dial design used a single pointer with a dual-drum digital counter (which I'm guessing evolved into the combination drum/pointer altimeter that later became nearly ubiquitous prior to the advent of the PFD)". The latter of which was a reference to the design you describe - apologies if that wasn't clear. The point I was trying to make was that the drum/dial design only scored marginally better then the experimental mechanical "tape" displays, and the additional information and graphical designs afforded by a CRT/TFT display would likely help reduce the discrepancy further.
Your last assessment of PF's performance is actually very close to my own with the exception that you have completely omitted the effects of the initial overcontrol induced roll PIO on PF's mental state.
Yes - I omitted it because my post was already tending towards essay-length!
What both AF447 crew members badly needed that night was to understand just how badly they were off altitude, then the airspeed implications would have been obvious.
Except that going by the CVR, there is no indication that the crew were unaware of what the altimeter display was telling them. I think what confuses the issue slightly is that translation from the French tends to mix up whether the PNF in particular is referring to pitch angle or altitude (hence the translation into "go up" and "go down" can refer to either). That said, whenever any of the pilots refers to the altimeter specifically after the stall has developed, they consistently say "You're going down", or words to that effect. The PNF is especially emphatic in this regard a couple of times.