Miloch wrote in
:

https://en.wikipedia.org/wiki/Bell_XFL_Airabonita


As a possible further reason for the rejection, it is often stated
that the Navy's position during that era was that all its aircraft
should use air-cooled engines (while the Allison was liquid-cooled).
This appears unfounded speculation. The U.S. Navy "would consider a
liquid-cooled engine installation provided a material increase in
performance over air-cooled engine can be shown."



The story I heard from veterans was that
liquid cooled engines were complicated to work
on and prone to damage even when not in combat.
The Japanese Hien "Tony" was an excellant design
but largely kept out of combat due the complexity
of repairs. Air cooled engines could have entire
cylinders shot off and still make it back to base,
whereas one hit in the cooling system would down
a liquid cooled plane. That was not overly critical
in the ETO but would mean death in huge expanses of
the Pacific.