France 90 mm/50 (3.5") Model 1926

France
90 mm/50 (3.5") Model 1926
Updated 05 April 2013

This gun was an improved AAA weapon intended to replace the 75 mm (2.95") AA guns used on older ships. Used an autofretted barrel and a semi-automatic Schneider breech mechanism.

The after section of Emile Bertin showing the 90 mm twin mounting

Sketch of 90 mm/50 Model 1926 gun and ammunition
Official drawing from the collection of Robert Dumas

Gun Characteristics .

Designation	90 mm/50 (3.5") Model 1926
Ship Class Used On (see Note 1)	Cruisers: Suffren, Emile Bertin and La Galissonnière Classes Net-layer Gladiateur and some escorts of the Élan and Chamois classes Fitted as emergency AA on Jean Bart
Date Of Design	1926
Date In Service	1931
Gun Weight	N/A
Gun Length	N/A
Bore Length	177.2 in (4.500 m)
Rifling Length	N/A
Grooves	N/A
Lands	N/A
Twist	N/A
Chamber Volume	N/A
Rate Of Fire (see Note 2)	12 - 15 rounds / minute
Notes: 1) All members of the Suffren class except Suffren herself carried this gun as their secondary battery. Suffren carried the older 76 mm/50 Model 1924. 2) Loading proved difficult at elevations above 60 degrees and ROF dropped to around 10 rounds per minute. 3) The Emile Bertin had an inadequate ammunition supply system which could only supply 20 rounds per minute for all four guns.

Ammunition .

Type	Fixed
Weight of Complete Round	39.7 lbs. (18 kg)
Projectile Types and Weights (see Note)	HE - 20.96 lbs. (9.51 kg) Incendiary - N/A Starshell - N/A
Bursting Charge	N/A
Projectile Length	15.2 in (38.5 cm)
Propellant Charge	6.83 lbs. (3.1 kg) BM5
Muzzle Velocity	2,789 fps (850 mps)
Working Pressure	N/A
Approximate Barrel Life	N/A
Ammunition stowage per gun (see Note 2)	Suffren - 500 rounds Emile Bertin - 250 rounds La Galissonnière - 300 rounds Others - N/A
Notes: 1) Actual French designations: HE - OEA Mle 1925 Starshell - OEcl Mle 1926 Incendiary - OI Mle 1927 2) The Emile Bertin class had ammunition space for 1,422 rounds but the standard combat loading was 1,000 HE plus 200 illumination rounds for the center mounting. La Galissonnière carried 2,400 HE and 200 illumination rounds.

Range .

Elevation	With 20.96 lbs. (9.51 kg) HE Shell
Range @ 45 degrees	16,885 yards (15,440 m)
AA Ceiling @ 80 degrees	34,800 feet (10,600 m)

Mount / Turret Data .

Designation	Single Mount Suffren class [except Suffren and Dupleix] (8) and Emile Bertin (2): Model 1926 Twin Mount Dupleix (4), Emile Bertin (1), La Galissonnière (4) and Jean Bart (5): Model 1930
Weight	N/A
Elevation	-5 / +80 degrees
Elevation Rate	N/A
Train	about +150 / -150 degrees
Train Rate	N/A
Gun recoil	N/A
Notes: 1) These mountings had automatic rammers but they were apparently difficult to load at angles over 60 degrees, thus limiting their effectiveness as AA weapons. 2) The single and twin mountings on Emile Bertin all fed from a single magazine. This had a single hoist that could supply 20 rounds per minute, an inadequate supply for even two guns let alone the four that she carried. This hoist ended on the upper deck and the rounds had to be carried to the mountings by hand.

Data from
"Naval Weapons of World War Two" by John Campbell
"Battleships: Allied Battleships in World War II" by W.H. Garzke, Jr. and R.O. Dulin, Jr.
"French Cruisers: 1922 - 1956" by John Jordan and Jean Moulin
"Cruisers of World War Two" by M.J. Whitley

Page History

09 October 2006 - Benchmark
28 March 2012 - Added sketch
05 April 2013 - Replaced picture of Emile Bertin, added information about ammunition supply for Emile Bertin