The French primarily relied upon depth charges for anti-submarine weapons for both world wars. France imported Italian Ginocchio towed torpedoes in the 1920s but trials with them were unsuccessful.

All depth charges of World War II used a hydrostatic pistol. Depth charges were designated by the weight of the warhead charge.

The following is adapted from "Find and Destroy: Antisubmarine Warfare in World War I" by Dwight R. Messimer:

The French produced insufficient numbers of DCs during World War I and the ones they did have were unreliable. In 1917 the French asked both the British and the USA to supply them with DCs, but both nations refused as they did not have the production capacity to supply both their own navies and the French. In a post war assessment, the French concluded that they should have simply copied the British Type D.

In 1918, 136 A/S depth charge throwers (DCT) were purchased from the British firm of Thornycroft.

Starting with the contre-torpilleurs of the Jaguar (2,100 tonnes) and the torpilleurs of the Bourrasque (1,500 tonnes) classes, ASW equipment consisted of two tunnels each holding 12 DC with an additional 12 DC stored in below-deck magazines. Later contre-torpilleurs carried 16 DC in each tunnel along with eight reloads.

All of the early interwar ships had stability problems due to topweight and as a result did not get the planned four DCT. Some ships received two DCT, but most only had deck reinforcement for planned wartime emergency fittings. Ginocchio towed torpedoes were fitted, but the resulting topweight again resulted in excessive topweight and technical problems halted further development in 1933.

In the late 1930s, 150 new Thornycroft DCTs were ordered, but few of these were installed by the time of the French surrender.

Depth Charges

Guiraud 40 KG

Date Of Design 1914
Date In Service 1915
Total Weight N/A
Explosive Charge 90 lbs. (40 kg)
Sink Rate / Terminal Velocity N/A
Settings Adjustable to 110 feet (35 m)

Used an obsolete torpedo detonator as part of the pistol. Not considered reliable.

Guiraud 70 KG

Date Of Design 1914
Date In Service 1915
Total Weight N/A
Explosive Charge 156 lbs. (70 kg)
Sink Rate / Terminal Velocity N/A
Settings Adjustable to 110 feet (35 m)

Used an obsolete torpedo detonator as part of the pistol. Not considered reliable.

Guiraud Model 1922 200 KG

Date Of Design 1922
Date In Service 1923 (?)
Total Weight 573 lbs. (260 kg)
Explosive Charge 441 lbs. (200 kg)
Sink Rate / Terminal Velocity 10 fps (3 mps)
Settings Original: 100, 165, 250 and 330 feet (30, 50, 75 and 100 m)
Improved: 130, 260 and 330 feet (40, 80 and 120 m)

Dimensions were 50 x 88 cm (19.7 x 34.6 in). This charge was used by destroyers and large destroyers and was generally dropped at 30 to 50 m (100 to 165 foot) intervals from enclosed roller chain stowagages which each held 12 DCs.

100 KG

Date Of Design N/A
Date In Service 1930 (?)
Total Weight 287 lbs. (130 kg)
Explosive Charge 220 lbs. (100 kg)
Sink Rate / Terminal Velocity 7.2 fps (2.2 mps)
Settings 100, 165, 250 and 330 feet (30, 50, 75 and 100 m)

Dimensions were 25 x 84 cm (13.8 x 33 in). This charge was carried by sloops and similar vessels. Could be dropped or fired from a DC thrower.

35 KG

Date Of Design N/A
Date In Service 1930 (?)
Total Weight 115 lbs. (52 kg)
Explosive Charge 77 lbs. (35 kg)
Sink Rate / Terminal Velocity 7.2 fps (2.2 mps)
Settings 80, 165, 250 and 330 feet (25, 50, 75 and 100 m)

This charge was for small warships.

Depth Charge Racks

The first Depth Charge Rack in French service was the USN Mark I, which was developed after the USN rejected the British practice of using a sling to hold a single DC. Developed with help from Lt. Cmdr. Ishwood, RN, deliveries of the Mark I started in April of 1918 and 250 American, British and French destroyers had them installed by the Armistice.

Designations for other French DC Racks are not available at this time. As noted above, during World War II contre-torpilleurs and torpilleurs used enclosed roller chain racks which held 12 or 16 DC.

Depth Charge Projectors of World War II

The French-built 100/250 M1928 mortar was on a trainable mounting and could throw 100 kg DC as far as 820 feet (250 m). As mentioned above, Thornycroft DCTs were purchased in 1918 and a modern model in the late 1930s which could throw 200 kg DC about 200 feet (60 m).

Ginocchio Towed-Torpedoes

Medium Type

Date Of Design N/A
Date In Service Not in service
Total Weight 137 lbs. (62 kg)
Explosive Charge 66 lbs. (30 kg)
Towed Depth 50 to 120 feet (15 to 37 m)

Heavy Type

Date Of Design N/A
Date In Service Not in service
Total Weight 166 lbs. (75.5 kg)
Explosive Charge 66 lbs. (30 kg)
Towed Depth Maximum of 175 feet (53 m)

French testing with these started in the late 1920s but were unsuccessful and all work stopped in 1933. With a war approaching, development resumed in 1939-1940 and these may have been carried by on the Le Hardi class and some torpedo boats.

Post-World War II

305 mm Mortar

Date Of Design N/A
Date In Service N/A
Total Weight 507 lbs. (230 kg)
Explosive Charge N/A
Range 440 to 3,000 yards (400 to 2,750 m)
Sink Rate / Terminal Velocity N/A

This was a four barrel 305 mm (12 in) mortar used only on the Commandant Rivière class. The rounds are time-fuzed with the fuze set inside the launch tube. The mortar is fired at the rate of one round per second, with reloading being performed via the muzzle. The continuous firing rate is four rounds in 25 seconds. Rounds are stowed in four carousels, with each one feeding one launch tube. Installation weights are 22 tons (22.2 mt) for the mortar, 18.5 tons (18.75 mt) for 72 rounds and 4.6 tons (4.7 mt) of fittings.

Sources

Data from:

  • "Naval Weapons of World War Two" by John Campbell
  • "The Naval Institute Guide to World Naval Weapon Systems 1991/92" by Norman Friedman
  • "Find and Destroy: Antisubmarine Warfare in World War I" by Dwight R. Messimer
  • "On Seas Contested: The Seven Great Navies of the Second Word War" by Vincent P. O'Hara, W. David Dickson and Richard Worth

Page History

23 May 2006 - Benchmark

16 October 2010 - Added information on World War I operations