To
FlyingOfficerKite!
Who knows if jet engines always provide optimum power?
This has been tested several times and unless you have a problem with our EPR system for this particular engine, the engines provide the thrust they are indicating to you.
Who knows if ALL the fleet will achieve comparable performance?
For the most they do, with minor cruise performance differences.
Who knows if the performance figures calculated by the airline will be achieved in practice under all conditions in all aircraft?
Why wouldn't they unless you make a grave mistake such as not including cargo, pax weight etc. in your calculations?
It would be interesting to take the actual weights of the passengers and compare them to the calculated standard weights to see if there is a significant variation
Here in the US, and I would assume in most other nations, the FAA conducts routine audits of these figures and they are pretty accurate.
As I indicated in my previous post, the current weigh job procedures, provided they are done accurately, are well within the margins of safety for aircraft performance.
Dag