It’s a growing problem on ramps all over the world—a diesel fuel additive called DEF—which on the flight line has several times been confused with the fuel system icing inhibitor PRIST. Mistaking DEF for PRIST can be disastrous and has already caused several engine-out landings in the U.S. and elsewhere.  Participants: Alex Beringer, Chief Operations Officer, Fair Wind Charters Ryan Smith, Captain, Falcon 900EX, Fair Wind Charters Michael Rossi, First Officer, Falcon 900EX, Fair Wind Charters