Hi guys!
As this scenario has been on my mind for quite a few years, I'd like to add a few things.
I definetely don't want to say anything to the point of "boy those guys were dreadful pilots" as we now know most of the facts of what happened on that day and they only had a few minutes to analyze the situation and their "solution" didn't work out.
There were, however, mistakes made and I am pretty sure such a scenario is recoverable if it happens outside a sim environment. I watched quite a few crews experience the same scenario in the sim. Everyone did ok - of course, as they knew something was gonna fail...
Regarding the statement above that VSI info is not static dependent and only IRS dependent, is not quite accurate. Correct, the IVSI used today does _require_: IRS data, but its not the only source of info. It needs both static and IRS data to function. IRS data is used to get a quick rough estimate of VSI through the vertical acceleration. This is then adjusted by the ADC's static info. So in a situation where the static is blocked, the VSI needle would most probably just fluctuate around 0 as it recieves info from the IRS that the aircraft is accelerating vertically (provided vertical speed is not constant), but the ADC will tell the VSI that there is no difference in static pressure, hence the needle will return to 0.
The only reliable data in such a scenario would be your EADI and GS data (provided the IRU's were recently aligned). Still, you should be able to decide whether you are stalling or overspeeding. Also, AoA indications are correct (stick shaker). The QRH includes thrust and pitch info which can be used in a scenario such as this.
There is another trick to determine AGL (without having to be below 2500 ft):
use the weather radar! Set a tilt of -6.5° and check the range at which you get ground returns. Multiply this by 1000 and voila, you have your AGL. Also works in the sim!
Obviously, surviving this scenario requires thorough info of the aircraft's systems and how data is aquired and used. Unfortunately, some pilots don't know their a/c that well.
Regards,
Mark