Bat (guided bomb)

Infobox Weapon
name= BAT (guided bomb)


origin=United States
type= Conventional
is_ranged=
is_bladed=
is_explosive=yes
is_artillery=
is_vehicle=
is_UK=yes
service = 1942 (Bomb MK 57)cite web|last=|first=|url=http://www.designation-systems.net/dusrm/app1/asm-n-2.html|title=ASM-N-2|work=Directory of U.S. Military Rockets and Missiles
accessdate=2007-12-24|publisher=] - 1953 (ASM-N-2)
used_by = United States Navy
wars = World War II
designer =
design_date=
manufacturer = National Bureau of Standards
production_date=
number = 2580cite web|last=Kopp|first= Dr Carlo|url=http://www.ausairpower.net/WW2-PGMs.html|title=The Dawn of the Smart Bomb|work=|accessdate=2007-12-24|publisher=Air Power Australia]
variants=
weight = Airframe and guidance package only - 600 lb (273 kg)
length = 11 feet, 11 inches (3.63 m)
part_length=
width = 10 feet (3.05 m)
height=
crew=
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diameter =
filling =
filling_weight = 1,000 lb bomb (1,600 lb (727 kg) gross)
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Bat was a radar-guided glide bomb developed by the United States Navy during World War II. Similar to the German Fritz X, Bat lacked any form of propulsion. However, because of its guidance system, Bat was not a gravity bomb and the Smithsonian National Air and Space Museum designates it a missile.cite web|last=|first=|url=http://www.nasm.si.edu/research/dsh/artifacts/RM-bat.htm|title=Bat Missile|work=Rockets and Missiles|accessdate=2007-12-24|publisher=Smithsonian National Air and Space Museum]

In January 1941 RCA proposed a new TV-guided anti-shipping weapon called Dragon. As with Operation Aphrodite's radio-controlled drones, an operator would use the TV image sent from the nose of the weapon and operate aerodynamic controls to put it on target. The National Bureau of Standards (NBS) would provide the airframe for use with a standard bomb. Work on the system progressed, but by the time it was ready for testing, the threat was now seen to be the German U-boat fleet.Fahrney, Delmar S., RADM USN "The Birth of Guided Missiles" "United States Naval Institute Proceedings" December 1980 p.60] The design was therefore modified in June 1942 to drop depth charges instead, and the guidance changed to an all-weather semi-active radar homing. This new design was named Pelican.

By mid-1943, the U-boat threat was dwindling, so the plans were changed again to use a new active radar homing system from Western Electric with a 2,000 lb general-purpose (GP) bomb. This form of the Pelican entered testing in Summer 1944, and in tests flown from Naval Air Station New York, it hit its target ship two out of four drops.

Production versions ("Bat") combined the original NBS airframe with a 1,000 lb GP bomb and the Pelican active radar system. The guidance system was gyrostabilized with an autopilot supplied by Bendix Aviation, and the steerable tail elevator was powered by small wind-driven generators. Development of this version was supervised by the Navy's Bureau of Ordnance in partnership with the Massachusetts Institute of Technology (MIT), with the NBS in charge of the overall development. Flight tests were conducted at the Naval Air Ordnance Test Station at Chincoteague Island, Virginia.

The antiship variant of the Bat (SWOD Mark 9 Model 0) eventually saw combat service beginning in April 1945 off Borneo, dropped by PB4Y Privateers (one bomb mounted under each wing) at altitudes of 15,000 to 25,000 feet (4,600–7,600 m) at airspeeds of 140 to 210 knots (260-390 km/h). Several Japanese ships were sunk, including a destroyer at a range of 20 nmi (37 km). Several Bats were also fitted with modified radar systems (SWOD Mark 9 Model 1) and dropped on Japanese-held bridges in Burma and other land-based targets.

The overall wartime record of the Bat was somewhat disappointing, as the guidance system was easily confused by radar land clutter, an important factor when attacking enemy ships close to shore, especially in the Philippine and Indonesian archipelagos.

The Privateer was the primary launch platform for the Bat, but other aircraft were also modified to launch the weapon, including the F4U Corsair, SB2C Helldiver, and TBF Avenger. The primary post-WWII aircraft to carry the weapon was the P-2 Neptune.

Hugh Dryden won the Presidential Certificate of Merit for the development of the Bat.

References and Notes

ee also

* Fritz X
* Henschel Hs 293
* Azon
* Razon
* Felix
* Gargoyle
* GB-8
* List of anti-ship missiles