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The GT-1 (Glide Torpedo 1) was an early form of missile developed by the United States Army Air Forces during World War II. Intended to deliver an aerial torpedo at a safe range from the launching aircraft, the weapon proved successful enough in testing to be approved for operational use, and the GT-1 saw limited use in the closing stages of the war.

GT-1 on B-25J.png
GT-1 glide torpedo mounted on North American B-25J Mitchell medium bomber
TypeAir-to-surface missile
Place of originUnited States
Service history
In service1944-1945
Used byUnited States Army Air Forces
Production history
WarheadMk 13 Mod 2A aerial torpedo
Warhead weight600 pounds (270 kg) explosive

Wingspan12 feet (3.7 m)
25 miles (40 km)
Speed260 miles per hour (420 km/h)
Preset plus paravane
B-25 Mitchell

Design and developmentEdit

The GT-1 was derived from the GB-1 series of glide bombs, developed by Aeronca for the United States Army Air Forces.[1] The weapon's airframe was inexpensive and simply designed, with a basic wing and twin tails attached to a cradle for carrying the payload.[1] The flight path of the GT-1 was determined by a preset autopilot that kept the weapon on a steady course after release.[1]

The GT-1 was usually released from its carrier aircraft at an altitude of 10,000 feet (3,000 m); this provided a standoff range of as much as 25 miles (40 km) under ideal conditions.[2][3] The GT-1's warload consisted of a Mark 13 Mod 2A aerial torpedo. The GT-1 was fitted with a paravane, trailing 20 feet (6.1 m) below the main body of the craft; upon the paravane's striking the surface of the water, explosive bolts would fire to release the torpedo, which would then execute a preset search pattern to locate and destroy its target.[1][2]

Operational historyEdit

Initially tested during 1943,[1][4] the GT-1 proved to be successful,[5] and was issued to a single operational unit for service.[6] Launched from North American B-25 Mitchell bombers,[1][7] the GT-1 saw brief operational service late in the war;[1][4] three missions are known to have been flown using the weapon from Okinawa in late 1945.[7] On one mission, against Kagoshima, eleven of thirteen GT-1s launched successfully entered the water; three hits were recorded, against a fleet carrier, a light carrier, and a freighter.[7] The Boeing B-17 Flying Fortress was also capable of carrying the GT-1.[3]

Following the end of World War II, the aerial torpedo rapidly fell out of favor as a weapon of war against surface ships[citation needed], and the 'GT' category of weapons was abolished in 1947.[8]

See alsoEdit


  1. ^ a b c d e f g Parsch 2003
  2. ^ a b Esquire 1947; Volume 28, p.70.
  3. ^ a b Army Ordnance, Volume 30, 1946. American Defense Preparedness Association. p.384.
  4. ^ a b Cate and Craven 1958, p.259.
  5. ^ Daso 1997, p.82.
  6. ^ Goebel 2010
  7. ^ a b c Hanle 2011
  8. ^ Mann 2008, p.256.
  • Craven, Wesley F.; James L. Cate (1958). USAF Historical Division (ed.). Men and Planes. The Army Air Forces in World War II. 6. Chicago: University of Chicago Press. ASIN B000ZIBK5G.
  • Daso, Dik A. (1997). Architects of American Air Supremacy: General Hap Arnold and Dr. Theodore von Kármán. Maxwell Air Force Base, AL: Air University Press. ASIN B0006F9WT4. Retrieved 2011-02-02.
  • Goebel, Greg (2010). "World War II Glide Bombs". Dumb Bombs & Smart Munitions. VectorSite. Retrieved 2017-05-14.
  • Hanle, Donald J. (January 2011). "Hail November". Air Force Magazine. 94 (1). Retrieved 2011-02-02.
  • Mann, Robert A. (2008). Aircraft record cards of the United States Air Force: How to Read the Codes. Jefferson, NC: McFarland & Company. ISBN 978-0-7864-3782-5. Retrieved 2011-02-02.
  • Parsch, Andreas (2003). "GB Series". Directory of U.S. Military Rockets and Missiles Appendix 1: Early Missiles and Drones. Retrieved 2011-02-02.