Pitot-static failure
Gotta admit, but detecting the pitot-staic failures due to icing and bugs or tape over the ports is different than detecting an electrical failure to the probes.
Only incident I had was a static freeze as I descended thru icing conditions ( heaters had failed). Was a no-brainer, as altitude on the steam gauges froze and IAS increased as I descended at a constant pitch. The HUD flight path marker stayed where it was supposed to, so very obvious what the problem was.
With AF447, a convenient flight path marker( derived from inertial data) on a HUD or some other display might have saved the day.
Comparing inertial/GPS data with the pitot-static measurements is hard in the cruise mode. The inertial data is noisy with altitude, and GPS altitude data is worse. The best display for we pilots is a flight path marker that shows what we are doing WRT the local horizontal. Don't even need AOA.
No comment/critique on PF actions, especially after comment "lost speeds".