Meikleor: Thanks very much, sure I get the 100kts thing is just an arbitrary number not intended for engine failure more a kinetic energy V squared thing for other failures. When operating both types I was very aware of the performance differences and as JT has mentioned I think it is good practice to sit in the armchair/bath/bar and think these things through. Interestingly my operator at the time did not utilise De-Rated power just Flex up to isa+60 (600) ie max flex 75 at sea level corresponding to a 40% power reduction. I don’t suppose you remember roughly what speed you had your failure at in the 300?