Originally Posted by
Dark Knight
However, considering the circumstances which caused the engine flame-outs a trimotor or 4 engined aircraft may have lost all.
The answer Dick is a question of probabilities. If one reviews the total components of an aircraft most are covered by MTBO (mean time between overhauls and/or MTBF (mean time between failure) determining when such component should be removed for inspection/overhaul or replacement.
Similarly ETOPS is based upon MTBAEF (mean time between all engine failure) predicated on statistical and operational data where the Actuaries consider and define probabilities which the Regulator makes the decision upon.
The total industry is based upon probabilities yet in 2017 we had a year without any airline fatalities.
Yes, so true! Also a lot of large twin engine flying all around the world, indicating how safe these aircraft are. Would be interesting to see how many flights suffered engine failure outside 60 minutes from a suitable airport.
2017 safest year for air travel as fatalities fall - BBC News