The Westland Whirland would just be an awsome aircraft to have. How many planes can you say had 4 cannons in 1940?? I can't really think of any.
Operational sorties with the Mk I Beaufighter began in September 1940.
The Whirlwind would be a fun ride, and a big plus for the EW Arena, but the Beaufighter is a much more significant WWII aircraft: served in a huge range of roles, nearly 6000 produced, operational in every theatre.
My personal preference, if a Beaufighter were introduced, would be for the Australian-built Mk 21; but any of Mk I, Mk VI, Mk X would be good alternatives.
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