F21 is a heavyweight torpedo developed by Naval Group for French Navy. Credit: Naval Group.
The F21 torpedo is powered by silver oxide-aluminium seawater primary battery. Credit: Business Wire.
The F21 torpedo was exhibited at the DEFEXPO event held in February 2020. Credit: Naval Group.

F21 is a new generation heavyweight torpedo developed by Naval Group, a French naval defence and marine renewable energy company. It is a high-performance torpedo intended for neutralising enemy submarines and surface ships.

The dual-purpose torpedo was primarily developed to replace the F17 mod2 torpedo on board the French Navy’s submarine fleet. The new Scorpene-class submarines of the Brazilian Navy will also be equipped with the F21 torpedo.

The F21 torpedo can be operated in deep waters and near coastal areas with high levels of noise and dense shipping.

F21 torpedo development

The qualification firing of the torpedo was conducted in a secured maritime area off the Var coast in June 2017. The tests were conducted from Pégase test vessel, COMEX’s vessel Janus and submarines.

Naval Group launched the torpedo during the Artémis programme led by the French Defence Procurement Agency (Direction Générale de l’Armement-DGA) in May 2018. DGA plans to equip all the French Navy’s submarines with F21 heavyweight torpedo.

Naval Group showcased F21 torpedo at DEFEXPO 2018 held in Chennai, India. It was also exhibited at the DEFEXPO held in Lucknow, India, in February 2020.

Orders and deliveries

Naval Group delivered a batch of six torpedoes to the French Navy in November 2019. The Brazilian Navy was handed over a batch of F21 torpedoes in January 2020.

In June 2019, the Defence Ministry of India issued a tender for the acquisition of F21 torpedoes for the Indian Navy’s new Scorpene-class submarines.

F21 torpedo design and features

The forward section of the F21 houses acoustic head and warhead, while the middle and rear sections accommodate energy, guidance and control and propulsion systems respectively. The torpedo uses wire guidance in initial phases of flight and also employs acoustic homing in subsequent phases for autonomous detection and tracking of targets. It has a length of 6m, diameter of 0.53m and a weight of 1.5t.

“It is a high-performance torpedo intended for neutralising enemy submarines and surface ships.”

The heavyweight torpedo is installed with a complete sonar suite and an advanced mission system, which helps to maintain clear tactical picture in confined coastal areas and against the most advanced torpedo defence systems.

The sophisticated discrimination, identification, acoustic counter-counter-measures (ACCM) and homing capabilities ensure the torpedo delivers optimal performance in all operational phases, including searching, tracking and attacking.


The torpedo is armed with a B2211D warhead, weighing up to 250kg. It has an overall length of 1.02m and a diameter of 533.4mm.

The insensitive explosive warhead is mechanically and electrically attached with the acoustic head section (AHS) and primary battery.

The warhead features an anodised aluminium hull divided into three compartments, including a chamber for the explosive loading, an impact fuse compartment and a tunnel for passing the electric cables between the acoustic head and other torpedo sections.

Fire control system of F21 torpedo

The MIGAL fire control system serves as an interface between the torpedo and the submarine’s combat information centre. It enables the operator to control the firing sequence during combat and training launchings.

The user-friendly interface helps the users in deploying different types of torpedoes from the same platform.

Propulsion and performance

F21 is powered by silver oxide-aluminium (AgO-Al) seawater primary battery. The electric propulsion system also integrates two contra-rotating propellers.

The AgO-Al seawater activated primary electrochemical stack helps to achieve maximum speed over an extended range. It also powers the on-board electronic control and guidance system.

The propulsion system enables the torpedo to travel at speeds between 25k and 50k. The torpedo has a maximum endurance of one hour and range of more than 50km. It has the capability to engage targets at a maximum depth of more than 500m.

Contractors involved

Saft received a multi-million contract to deliver AgO-Al electrochemical stacks for the F21 torpedoes in June 2014.

EURENCO is responsible for supplying the warhead of the torpedo.