Re AD 2013-24-01 (#49); another masterpiece from DOT / FAA, but at least they do try
“…prohibit operation in moderate and severe ICI conditions” This is a very thin safety line particularly where the conditions cannot be detected directly, only by supposition based on WXR defined Cb activity.
And what are moderate to severe ICI conditions vice conventional icing conditions – don’t you have to be in them to know the difference.
The industry has a new hazard; MCS –
“a large Mesoscale Convective System … where several thunderstorms have merged, with a continuous cloud larger than 100 kilometers (62 miles) across.”
Events with other aircraft types were not necessarily constrained to
“warm geographic locations” or above 30000ft. Also, not all of the likely conditions would be identified by the crew, e.g. as being in cloud, some of the very thin wispy cirrus conditions may not constitute IMC.
Is the industry pushing the safety assumptions a bit far by allowing a dispatch after only three engines have been inspected. Is it more likely that a ‘damaged’ engine will fail at high thrust during takeoff .
What if ICI conditions are encountered and an engine suffers damage without any EICAS alerting?
“ … unrecoverable thrust loss on multiple engines can lead to a forced landing.” There must an award for such a statement.