jt-
quote-(a) you seem to presume that the takeoff is ALWAYS AEO TOD limited ie there will be a 15 percent pad. This usually will be the case for low weight, low altitude, low OAT, takeoffs ie where the OEI performance is comparatively good and the AEO factor results in the AEO case being the more limiting for the AFM schedules. More generally, though, in real world commercial operations, the OEI case will be the more limiting and the 15 percent pad associated with the AEO case becomes irrelevant. More importantly, the heavyweight takeoff aircraft on a limiting runway is going to be VERY close to the end of the TORA (runway) when it finally drags itself into the sky ....
I've had the long held belief (and I don't remember where I learned it) that a 4 engined jet transport was NEVER balanced field limited, but rather always limited by the 115% AEO requirement, and the 2 engine a/c is limited by stop/go and virtually never by 115%. There may be exceptions to many rules, but in general is this belief correct?......or are there enough exceptions that I must change my memory?
...assuming, of course that the t/o is not limited by another factor such as brake energy, tire speed, etc........