Mark 54 Lightweight Torpedo

The Mark 54 Lightweight Torpedo (formerly known as Lightweight Hybrid Torpedo, or LHT) is a standard 12.75-inch (324 mm) anti-submarine warfare (ASW) torpedo used by the United States Navy.

Mark 54 Lightweight Torpedo
WTUS PostWWII mk54 pic.jpg
Mark 54 Torpedo aboard the USS Ross (DDG-71) in March 2008.
TypeLightweight torpedo
Place of originUnited States
Service history
In service2004–present
Used byUnited States Navy
Royal Australian Navy
Indian Navy
Royal Air Force
Royal Thai Navy
Royal Netherlands Navy
Production history
DesignerRaytheon Systems
Unit costUS$839,320 (FY2014)[1]
Mass608 lb (276 kg)[2]
Length106.9 in (2.72 m)[2]
Diameter12.75 in (324 mm)[2]

Warhead weight96.8 lb (43.9 kg)[2]
Blast yield238 lb (108 kg) TNT

EngineReciprocating external combustion
PropellantOtto II (liquid)
10,000 yd (9.1 km)
Maximum speed >40 kn (74.1 km/h; 46.0 mph)
Active or passive/active acoustic homing
Mark 32 Surface Vessel Torpedo Tubes, ASW Aircraft, RUM-139 VL-ASROC


The Mark 54 was co-developed by Raytheon Integrated Defense Systems and the U.S. Navy under the U.S. Navy's Lightweight Hybrid Torpedo program in response to perceived problems with the extant Mark 50 and Mark 46 torpedoes. The Mk 50, having been developed to counter very high performance nuclear submarines such as the Soviet Alfa class, was seen as too expensive to use against relatively slow conventional submarines. The older Mk 46, designed for open-ocean use, performed poorly in the littoral areas, where the Navy envisioned itself likely to operate in the future.

USS Roosevelt (DDG-80) launches a Mk 54 torpedo.

The Mk 54 was created by combining the homing portion of the Mk 50 and the warhead and propulsion sections of the Mk 46, improved for better performance in shallow water, and with the addition of commercial off-the-shelf (COTS) technology to further reduce costs. It shares much of the software and computer hardware of the Mk 48 ADCAP heavy torpedo, based around a custom PowerPC 603e microprocessor.

Developmental testing began in July 1999, and a successful critical design review was completed in November 1999.

In April 2003, Raytheon was awarded a sole source contract for the production of the Mk 54. Full rate production began in October 2004. In March 2010 the Fifth Fleet requested improvements in the Mk 54's performance against diesel-electric submarines via an Urgent Operational Need Statement (UONS). This led to a software Block Upgrade (BUG) program which began testing in August 2011 and which continues, having been criticised by the Director, Operational Test and Evaluation (DOT&E) for using unrealistic proxies for threat submarines.[3]

The Mk 54 can be fired from surface ships via the Mark 32 surface vessel torpedo tubes or the vertical launch anti-submarine rocket (ASROC) systems, and also from most ASW aircraft, although they are slightly different lengths and weights. The P-8 Poseidon uses the High-Altitude Anti-Submarine Warfare Weapons Capability (HAAWC) GPS-guided parachute kit to drop torpedoes from high altitude.

The FY14 DOT&E report assessed the Mk 54 (BUG) torpedo as not operationally effective in its intended role: "During operationally challenging and realistic scenarios, the Mk 54 (BUG) demonstrated below threshold performance and exhibited many of the same failure mechanisms observed during the FY 2004 initial operational testing". Shortfalls were also identified with the employing platforms’ tactics and tactical documentation, and interoperability problems with some platform fire control systems.[4]


Current operatorsEdit

  • Brazilian Navy - In December 2020, the US Department of State approved for $70 million, the sale for Brazil of 22 Mk 54 lightweight torpedo conversion kits for the Mk 46 Mod 5A torpedoes already in operation in the S-70B helicopters of the Brazilian Navy, plus ancillary training, exercise and maintenance spare parts.[6][7]

In May 2019 Canada requested 425 Mk 54 lightweight torpedo conversion kits, plus ancillary training, exercise and maintenance spare parts. This procurement will allow Canada to upgrade its current inventory of Mk 46 torpedoes. The Mk 54 lightweight torpedoes are expected to be used on the Royal Canadian Navy's Halifax-class frigates, and the Royal Canadian Air Force's CP-140 Aurora aircraft. The torpedoes are also planned to be deployed from the CH-148 maritime helicopters.[8] On 17 May 2019, the U.S. State Department approved the sale worth US$387 Million (C$514 Million in 2019.) Under Canada's Industrial and Technological Benefits Policy, Canada negotiated an Offset agreement with Raytheon before signing the final deal in order to leverage jobs and economic benefits in Canada.[9]

  • Indian Navy - In June 2011, it was reported that India will get 32 Mk 54 All-Up-Round Lightweight Torpedoes and associated equipment, parts, training and logistical support for an estimated cost of $86 million through U.S. government's Foreign Military Sales program for P-8I LRMP.[10]
  • Mexican Navy - In early 2018 the U.S. State Department approved the sale of Mark 54 torpedoes to the Mexican Navy, who will deploy them from their new Sigma-class design frigates, the first of which is being jointly built with Dutch shipbuilding company Damen Schelde Naval Shipbuilding.[11] In April 2018, the US State Department cleared the sale of an additional 30 Mark 54 torpedoes to the Mexican Navy, which may be carried on MH-60R helicopters, which the Mexican Navy plans to order in the near future.[12]
  New Zealand
  • Royal New Zealand Air Force - Have an undisclosed number with the purchase of the P8-A. It was known that the upgrade from the Mk 46 was going to happen via the "Defence Capability Plan 2019" and was stated in the RNZAF News (Page 25) [13] that weapons was the Mark 54 Torpedo. It is unknown whether the Royal New Zealand Navy have replaced their Mk46 at this stage.
  United Kingdom
  • Royal Air Force - In January 2018 it was announced that the P-8 Poseidon aircraft to be operated by the RAF will carry the Mk 54.[14]
  United States

See alsoEdit


  1. ^ "Senate Report 113-044 - NATIONAL DEFENSE AUTHORIZATION ACT FOR FISCAL YEAR 2014". Library of Congress. 20 June 2013. Retrieved 7 November 2013.[permanent dead link] 150 Mk 54 cost $125.898m in financial year 2014
  2. ^ a b c d "Fact File: Mk54 Torpedo". US Navy. 27 November 2012. Archived from the original on 13 May 2013. Retrieved 7 November 2013.
  3. ^ "Mk 54 Lightweight Torpedo" (PDF). Director, Operational Test & Evaluation (DOT&E). 2012. Archived from the original (PDF) on 26 August 2014. Retrieved 7 November 2013.
  4. ^ "Mk 54 Lightweight Torpedo FY14" (PDF). Director, Operational Test & Evaluation (DOT&E). 2015. Archived from the original (PDF) on 31 May 2015. Retrieved 25 January 2015.
  5. ^ "Team Torpedo: US Firms Sell & Support MK48s and MK54s". Defense Industry Daily. 21 August 2014. Archived from the original on 16 September 2012. Retrieved 12 October 2010.
  6. ^ "Proposed Purchase of MK 54 Torpedoes by Brazil Approved". U.S. Embassy and Consulates in Brazil. 2 December 2019.
  7. ^ "Brazil - Mk 54 Lightweight Torpedoes". DSCA. 2 December 2019.
  8. ^ Archived 23 May 2019 at the Wayback Machine - 22 May 2019, Naval Technology
  9. ^ Coyne, Todd (13 June 2019). "Canada to spend $500M on U.S. anti-submarine torpedo". CTV News Vancouver. Retrieved 10 February 2022.
  10. ^ "US clears sale of anti-submarine torpedoes to Indian Navy". The Indian Express. 28 June 2011. Archived from the original on 15 September 2012. Retrieved 29 June 2011.
  11. ^ Archived 4 May 2018 at the Wayback Machine January 2018, Defense Security Cooperation Agency
  12. ^ Archived 4 May 2018 at the Wayback Machine - April 2018, The Defense Post
  13. ^ "P-8A POSEIDON ORDNANCE". Air Force News Feb 23. Issue 254.{{cite web}}: CS1 maint: url-status (link)
  14. ^ "Britain to Purchase Mk 54 Lightweight Torpedo array kits destined for P-8 Poseidon". UK Defence Journal. 4 January 2018. Archived from the original on 5 January 2018. Retrieved 4 January 2018.

External linksEdit