zlacker

Trijets were mostly a thing to allow operations further away from diversion airports. Until the mid 80s twin engine jets had to stay less than an hour from diversion airports which meant that most stuff over water or remote routes had to be trijet or quad.

The MD-11 was late to that party, and by the time they started flying they were already allowing twins to go farther. Now the limit is all the way up to 370 minutes from the nearest airport for some twins, and most are capable of flying transatlantic.

>>dghlsa+(OP)
My personal theories as far the current grounding of all MD-11s:

1. Boeing wants no more responsibility for these airframes. Good call by the Board.

2. MD-11 style engine arrangement is an entire design flaw in itself. You can only recover from an uncontained engine failure at V1 if two engines remain. Good luck with that since on the MD-11, engine #2's intake is in the debris field of the other two turbines.