[robtek]

I really can't understand why there is still disagreement about the max. speed of the Bf109E.

When the manufacturer calculates a speed for a model and verifies this with flight-tests, and sells the plane according to this values

to a known nitpicking customer, the values must be correct or the manufacturer is out of business..

The interest of the manufacturer is to get no rejects, so the production is streamlined to minimize the tolerances.

There is still no real pressure on the manufacturer at this time (1940) to meet the demands, so peacetime quality can be assumed to be met.

When we have now a projected max. speed of 500 km/h i would think that the majority of delivered Airframes met or surpassed this speed.

As even slight faults of the airframe or the pilot would mark the plane as unacceptable, the manufacturer will try to err to the safe side.