These conditions are apparently very rare and elusive. I wonder how long Boeings test airplane has to fly before it encounters the conditions of the ABC 747-8 incident, if it ever finds them.
I understand that changes to the certification requirements are in the proposal phase. When adopted, they will only apply to new certifications. How do manufacturers qualify their engines for conditions that are never there when you need them?
An interesting element is that the ABC airplane was deviating around a thunderstorm, as was AF447. The pilot of AF447 had the impression that they were just below the top of the ice particle cloud they were entering. Satellite and radiosonde data indicate that cloud tops in the area were higher than 50,000 ft. Perhaps they were entering a new cell that was just building up below them, and the particular ice particles are unique to that situation?
Interesting also that the TAT probes iced up, but no airspeed anomalies.
Last edited by HazelNuts39; 27th Aug 2013 at 08:51.