                       The Me262A-1a/U4

One of the more intersting versions of the Me262 to be tried
was the Me262A-1a/U4, which mounted a 50mm BK5 cannon in the
nose.  This huge antitank gun was intended to be used as a
bomber-killer.  To quote from "Warplanes of the Third Reich:"

     "A more spectacular installation was provided by a 50mm
Rheinmetall BK 5 first tested in a modified Me 262A-1a (Werk-
Nr. 130083), the barrel of the immense cannon projecting
almost 7 feet ahead of the fuselage.  The BK 5 was installed
well forward of the c.g., necessitating the provision of a
compensating weight in the rear fuselage, and the nosewheel
had to be modified so that it would swivel to lie flat
beneath the weapon.   Somewhat surprisingly, its installation
had no harmful effect on performance, and during air-to-
ground firing trials, between 25 and 27 hits were repeatedly
scored from a possible 30 against a rectangular target 105 ft
in length (representing the span of a heavy bomber) from
altitudes between 3940 and 4920 feet."

This plane has the 21 round cylindrical drum for the BK 5
50mm cannon as was used in the Me410A-1/U4.  The top speed
has been reduced to 500 mph to reflect the extra weight of
the weapon system.
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