Bf 109F - improved air intake design?

[DavidIsby]

One of the reasons that the Bf 109F had better high-altitude performance than the Bf 109E was that its redesigned cowling included an air intake that increased the ram recovery ratio ( the percentage of possible air that makes it into the supercharger intake) from the 37.5 percent of the Bf 109E-3.

Does anyone know a source for the increased ram recovery ratio for the Bf 109F?

Thanks,
David Isby

[ouidjat]

Hi David,

That the mass-flow was higher on Bf109F than on Bf109E scoop is one thing; but
I wonder if the ram recovery rate has any significance on low mach numbers (around 0,2 for that plane)....

Franck.

[the_ivan]

According to Mtt AG (Meßprotokoll vom 18.4.38), the standard E intake had an efficiency of ~76% at VDH and high-speed.

The F-G intake is given as 90% at VDH and hi-speed, but I don't recall having seen a report where it's actually measured (DB did some when testing different alternatives, but always at climb speed IIRC).