Military Wiki
Mark 45 torpedo
Mark 45 Nuclear Torpedo.jpg
Mark 45 torpedo on display in Aiea, Hawaii, United States
Type Nuclear antisubmarine torpedo[1]
Place of origin United States
Service history
In service 1958-1976[1]
Used by  United States Navy
Production history
Designer Applied Research Laboratory, University of Washington[1]
Westinghouse Electric
Designed 1957[1]
Manufacturer Westinghouse Electric[1]
Produced 1959[1]
Number built 600
Variants Mark 45 Mod 1[1]
Mark 45 Mod 2
Weight 2,400 pounds (1,100 kg)
Length 227 inches (580 cm)
Diameter 19 inches (48 cm)

Warhead W34 nuclear warhead
Blast yield 11 kilotons

Engine Electric[1]
5-8 miles (8-13 km)
Gyroscope and wire

The Mark 45 anti-submarine torpedo, a.k.a. ASTOR, was a submarine-launched wire-guided nuclear torpedo designed by the United States Navy for use against high-speed, deep-diving, enemy submarines. The 19-inch (480 mm)-diameter torpedo was fitted with a W34 nuclear warhead. The need to maintain direct control over the warhead meant that a wire connection had to be maintained between the torpedo and submarine until detonation. Wire guidance systems were piggybacked onto this cable, and the torpedo had no homing capability. The design was completed in 1960, and 600 torpedoes were built between 1963 and 1976, when ASTOR was replaced by the Mark 48 torpedo.


This electrically propelled, 19-inch (480 mm)-diameter torpedo was 227 inches (5,800 mm) long and weighed 2,400 pounds (1,100 kg).[2][3] The W34 nuclear warhead used in ASTOR had an explosive yield of 11 kilotons.[citation needed] The requirement for positive control of nuclear warheads meant that ASTOR could only be detonated by a deliberate signal from the firing submarine, which necessitated a wire link. Because of this, the torpedo was only fitted with wire guidance systems (transmitted over the same link), and had no homing capability.[citation needed] The torpedo had a range of 5 to 8 miles (8.0 to 12.9 km).[3] By replacing the nuclear warhead and removing the wire guidance systems, the torpedo could be reconfigured for unguided launch against surface targets.[2]


Development of ASTOR was completed in 1960 and it entered service in 1963.[citation needed] Approximately 600 torpedoes were built by 1976, when the torpedo was replaced by the Mark 48 torpedo.[citation needed] The ASTORs were collected, fitted with conventional warheads and wake homing guidance systems, then sold to foreign navies as the Mark 45 Mod 1 Freedom Torpedo.[3]


  1. 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 Jolie, E.W. (15 September 1978). "A Brief History of US Navy Torpedo Development: Torpedo Mine Mk45". Retrieved 24 June 2013. 
  2. 2.0 2.1 Kurak (September 1966) p.147
  3. 3.0 3.1 3.2 Polmar (November 1978) p.160


  • Kurak, Steve (September 1966). "The U. S. Navy's Torpedo Inventory". United States Naval Institute Proceedings. 
  • Polmar, Norman (November 1978). "The Ships and Aircraft of the U.S. Fleet: Torpedoes". United States Naval Institute Proceedings. 

This page uses Creative Commons Licensed content from Wikipedia (view authors).