Quote:
Originally Posted by IvanK
A good selection on the WWII aircraft performance site. Interesting comment on items 13 and 14 ... the ones with 500Kmh IAS at sea level.
|
Thanks for your inputs guys.
IvanK I am disregarding items 13 and 14 as they have no 'provenance', i.e. no acknowledged testing organisation although the speed test is close to the V15a tests so they are possibly based on a prototype perhaps simplified for publication.
For interim information: I am testing the 109E-3 at 1.3ata and 2400rpm, radiator 1/4 open which aligns with the Swiss tests which are very close to the handbokk figures until 5,000m where they fall away more than the handbook. The French tests at 1.3ata 2400rpm produced better results to 4,000m but it was probably an E-1 and curiously the radiator was open to 4,000m due to cooling problems. The average of all the six data sets I have is quite close to the handbook, 2%-3% above handbook at low altitude and matching the handbook in the 4,000m to 7,000m region. In any case, the CoD 109E-3 is below all those figures and is looking like 93-95% of handbook figures at altitudes to 1,500m and around 98% at 5,000m. I still have more tests to do at other altitudes.
Of course I don't know if the various figures are supposed to be max speeds or just representave performance at those power settings so I don't know of we can compare them with Spitfire Max Speeds. We can at least see if CoD 109s are perfoming near to those historical tests - or not.
I'll post results here when I finish.