A quad 28 mm (1.1"/75 cal) Mk 1 anti-aircraft gun firing on the U.S. aircraft carrier USS <i>Hornet</i> (CV-8) in May 1942.
Cdr. John Ford, USNR
U.S. Navy "Battle of Midway" movie screenshot <a rel="nofollow" class="external autonumber" href="http://www.navy.mil/midway/john_ford_theater.html">[1]</a>