Perhaps selling issues. Sounds nicer to have a spec at 500 +/-25 kmh than 485 +/-10kmh.

The thing is there seems to be no test on the E series that indicates that there had effectively 109s that reached speeds above 500 kmh.

It is an average. There is no "probably something less" or "selling issues". No pointy tin-foil required. This is standard stuff in aviation.

Of course there are flight test's that show that average performance....

Here:

http://kurfurst.org/Performance_test...chreibung.html

That is the Yugoslavian test we've had here few pages back. There is no mention of the aircraft actualy achieving 500km/h, at least I can not see it anywhere.

It is German test but is reprinted in a Yugoslavian report. Of course it is, the Yugoslavian's purchased Bf-109E's...

The Yugoslavian report is used to date the German one.

Sure there is:

They flew at full power for 1.1hours, to altitudes of 6000m, and the total flight lasted 2 hours.

http://kurfurst.org/Performance_test...chreibung.html

Ok, we can ballpark the vicinity of the speeds we should be seeing at each of the settings by using the basic math relationships of power required to power available. Most of you won't know what I am talking about but it works.

For these ratings:

2) Startleistung 1175 PS in 0 m Höhe = 500kph
(zulässige Dauer 1 Min.)
bei 2500 U/Min.

3) Bodenleistung 1015 PS in 0 m Höhe = ~474kph
Kurzleistung (5 Min. Dauer)
bei 2400 U/Min.

Erhöhte Dauerleistung 950 PS in 0 m Höhe = ~465 kph
(zulässige Dauer 30 Min.)
bei 2300 U/Min.

Dauerleistung 860 PS in 0 m Höhe = ~449 kph
bei 2200 U/Min.

That is based on Mtt's contractual performance with the RLM and of course has a +/- 5% and assumes the radiator is in the same position as the 1 minute rating. This is a quick ballpark and it can be refined.

For those not familiar with the math:

http://mit.edu/16.unified/www/FALL/t...es/node97.html

I really have no clue where you find the test-flown 500 kph ... please indicate the corresponding paragraphe or sentence.

Proper translation:
"Endurance at full throttle is 1.1h at 6000m altitude.
With according throttling, endurance is increased to two hours."

It's the part of the technical description labelled "Endurance".

I know that, but the actual data is (again) the same Mtt data, the only source provided by the manufacturer. It even says so in the description.

I speak German but I honestly can't see this test confirming the Vmax values stated in the manufacturer's brochure.

Thanks very much. I put it into the table posted earier. Only difference (probably typo) was the PS for Bodenleistung. What is the position of the radiator? What would the values for A-1 be? What would the drag penalty for E-4 Haube be and what would the drag penalty for bombrack be, if you happen to know?

DB 601 Aa / 9-9518E

1.45 ata 2500RPM 1175HP (1 minute) - 500km/h
1.35 ata 2400RPM 1045HP (5 minutes) - 474km/h
1.15 ata 2300RPM 950HP (30 minutes) - 465km/h