Originally Posted by FlyingOfficerKite
However, many aircraft have crashed in the past because of lack of this absolute knowledge of weight and performance and they will continue to do so in the future.
Would you mind substantiating that claim by a number of concrete examples?
The standard tables and calculations include a big safety margin, and even a bit overweight, and with a bit less-than-rated power will ensure safe operation.
If the intakes or tailpipes are not badly deformed, identical engine types will produce the same thrust at the same EPR value. With less-than perfect engines it may vary with N1, and with fuel flow, but not with EPR.
Bernd