The primary aspect of U.S. World War II torpedo development, apart from copying electric torpedoes, was the design of a air-launched homing torpedo, fast enough to catch a submerged submarine, yet slow enough to enable the torpedo to hear the noise of a submarine over the flow noise created by itself. 12 knots was thought to be perfect.
Work by General Electric, Harvard and Bell Laboratories, begun in 1941 led to the Mk 24 "mine", a designation maybe due to security necessities, which carried a 42kg Torpex charge, enough for the expected impact detonation. The torpedo could run for up to fifteen minutes, yet most hits were scored directly after the submarine's dive.
weapons carry within the Navy were
the TBF Avenger and PBY Catalina, which employed the weapon in lieu of
and supporting depth charges. The first victim
of the new weapon was U-467, sunk by
a plane of VP-84 in the Atlantic, May 25th, 1943. Following her would be
31 boats, with another 15 damaged.
(Numbers for the U.S. Atlantic Fleet only, no figures found for Pacific
drops. Likely none were executed. Weapon is included for
the sake of completeness and the possibility that it actually WAS used.).FIDO
could be dropped at 125 knots from 250 feet. FIDO homed via four hydrophones
and a simple steering mechanism pointing the torpedo toward the
source of the noise.
Typical mission profiles included forcing the submarine to dive, then drop the torpedo onto its head.
||Year of Construction:
Weight: 308 kg / 680 lbs
Length: 2134mm / 7ft 0in
Range: 3660 m / 4000 yds at 12 knots
Explosive Charge: 42 kg / 92 lbs Torpex