Messerschmitt Bf 109 in Action: Part 2 (Aircraft 57)
By J.B. Beaman
Publisher: Squadron/Signal Publications 1983 61 Pages
PDF 17 MB
During the early spring of 1940, well before the Battle of France began, the Messerschmitt design team at Augsburg set about updating and refining their progeny. Designed to take full advantage of the more powerful 1350hpDB 601E engine the resultant Bf 109F series has been claimed by many to have carried Messerschmitt's fighter to the "crest of its evolution".
Using standard Bf 109E-4 air frames, Werk-Nrs 5601-5604, four prototypes, V21, V22, V23 and V24 respectively were built to test various aerodynamic and powerplant revisions. The F was designed as an exercise in lessening air drag beginning with a completely new cowling designed to enclose the DB 601E engine and with a slightly deeper oil cooler bath underneath the cowling. The new round supercharger air intake was moved further out from the side of the cowling to obtain a greater ramming effect. The spinner was considerably enlarged and rounded while the propeller blades were shortened from 10FT2iNto 9ft 8V21N. The wing mounted MG FF cannon were deleted in favor of a single, engine-mounted Mauser MG 151 firing through an aperture in the spinner. This weapon not only had a higher muzzle velocity and rate of fire than the MG FF but was being developed in both a 15mm and 20mm version.
The wing which had remained essentially the same since the prototype, was structurely unchanged. The underwing radiator was streamlined, being flatter but wider for less drag, providing an air discharge through a duct in the upper portion of the inboard flap which was split length-wise to form a double flap, the radiators were also enlarged horizontally thus providing the same amount of cooling area. The wing leading edge slots were reduced in length as were the flaps which were increased in chord so that their area remained unchanged. The wingspan was reduced, but because of the detrimental effect on handling, detachable semi-ellipitcal wing tips were added.