One trick this SLF learnt years ago in the RNZAF days (from an aborted takeoff). Set your stop watch at start of takeoff roll. If you have still not rotated after 45 seconds get ready for the worst and make sure you have the nearest exit mapped in your mind. Pretty much works for most a/c types flying out there. When I put my life in some junior jocks hands, I want to know that I still have a little bit of control over a stuff up. Shabu Shabu anyone?