Richelieu-class battleship

The Richelieu-class battleships were the last and largest battleships of the French Navy, staying in service into the 1960s. They still remain to this day the largest warships ever built by France. Designed in the 1930s to counter the threat of the Italian s, the Richelieu class were essentially scaled-up versions of the preceding, featuring a main battery of eight 380 mm guns in two quadruple turrets in forward superfiring positions.

Four Richelieu-class ships, of three different subclasses, were designed over the course of three naval construction programs, in 1935, 1936, and 1938; only three were laid down. Only the first two units, the FRENCH BATTLESHIP Richelieu and the FRENCH BATTLESHIP Jean Bart, were ever completed. They saw service during World War II, first under Vichy control in Dakar (1940) and Casablanca (1942), then under the Allies' control, the Richelieu participating in British Home Fleet and Eastern Fleet operations and supporting the French forces' return to Indochina in late 1945. The Jean Bart was not completed until the 1950s, and took part in the operations off Port Said (Egypt) during the Suez Crisis in 1956. The Richelieu was scrapped in 1968 and the Jean Bart in 1970.

Washington Naval Treaty: Consequences
In 1922, the Washington Naval Conference, concluded by the Washington Naval Treaty, decided to stop for ten years any new battleship building, as a new naval armaments race was developing between the United States of America, the United Kingdom, and Japan. The Treaty fixed limits for new battleships of 35000 LT standard displacement, and 406 mm for the main battery's artillery caliber. France and Italy each were also allowed (after 1927) to replace two of their old battleships.

Germany was not subject to the Washington Treaty limitations, but instead to the more stringent Treaty of Versailles restrictions. It was forbidden to build any warship with a displacement greater than 10000 LT.

But the practicality of building battleships seemed very questionable as, during World War I, no decisive victory had resulted from a cataclysmic clash between battleships, unlike the Japanese victory of Tsushima more than 17 years earlier. However, the war experience had clearly shown the problem of ensuring the safety of maritime commercial routes against commerce raiders, for which cruisers appeared better suited than battleships; thus, by the late 1920s all the countries which had signed the Washington Treaty undertook the building of new heavy cruiser classes. For France, the priority was the safety of the waterborne connections between France and her African colonies/protectorates (via the Marseille-Algiers and Bordeaux-Casablanca-Dakar routes).

Thus, in the late 1920s, the most powerful battleships had been designed before the Washington Treaty, and were armed with four double turrets of 15 in or 16 in caliber guns. The s, built between 1922–1927 with three triple 16-inch turrets forward, were based on the 1921 G3 battlecruiser concept. The top speed was, for most battleships, 21 - 25 kn; the s had 26.5 kn top speeds; and a few in Western waters, the fast battleships or battlecruisers, had top speeds exceeding 30 kn.

But neither France nor Italy were intending to build battleships similar to the most recent American, British, or Japanese battleships: very heavily armed and armored. They only wished to modernize their aging battleships, refurbishing the propulsion machinery and upgrading the main artillery; the Treaty of Washington authorized them to undertake much more radical modernizations than the other treaty powers. In the same way, both powers reserved the right to employ their replacement capital ship tonnage allocation (70000 LT) as they saw fit, subject to Treaty limits: not only were two battleships of 35000 LT possible, but also three of 23000 LT or four of 17500 LT.

French battleship projects: 1926–1929


The Treaty of Washington was resented as humiliating: it only allowed France the same global battleship tonnage (175000 LT) as Italy, one-third that of the United States and the United Kingdom, and 5/9th of Japan's. However, battleships were not the core of the Statut Naval French warship building program, adopted by the French Parliament in 1924. Its aim was to enable the French Navy to counter the navies of both Italy and Germany. From 1924 to 1932, the annual Tranche Navale (literally, a "slice" of the Statut Naval) included only cruisers, destroyers, torpedo-boats, and submarines.

The French Admiralty, under Vice Admiral Salaün, discussed in 1926–1927 ships designed as cruiser killers; these would be able to outgun and outrun the Italian heavy cruisers, which were considered the main threat against the waterborne connections between France and North Africa. The first Italian heavy cruiser unit built, the ITALIAN CRUISER Trento, had been laid down in 1925 and launched in 1926. The French designers considered a displacement of 17500 LT which would have allowed them to build four units under the maximum limit of 70000 LT (from the Treaty of Washington) for the authorized French replacements. An artillery arrangement of two 305 mm 55-calibre quadruple turrets forward was examined, combining the choice of quadruple turrets made by the French designers of the prewar  and the all forward arrangement of the Nelson-class battleships. The top speed would have been 34 –, the armor able to resist 203 mm shells. Ultimately, however, it was concluded that such warships would not have been able to fight in the line of battle against the old Italian battleships.

In 1927, studies were undertaken of 37000 t battlecruisers. This trial displacement would have been the equivalent of a standard Washington-Treaty displacement of 32000 –, near the maximum limit for battleship displacement fixed by the Treaty of Washington. However, it was clear that the building of 35000 LT battleships would surpass the French Navy's technical and financial capacities at the time: the building costs of the required infrastructure for hulls of about 230 – length, allowing them to reach a speed of 27 –, would have been enough to buy two more battleships, and would have jeopardized the building program for the other categorizes of warships (cruisers, destroyers, and submarines).

Moreover, at the same time, discussions at the Disarmament Subcommittee of the League of Nations had begun in Geneva, about the pursuit of naval armaments limitation policy. The United Kingdom was trying to obtain more drastic limitations than the Washington Treaty's, with a battleship maximum displacement of 25000 LT and a battleship maximum caliber of 305 mm, and the French government did not wanted to jeopardize the negotiations.

The 23,000-tonne battleship
In February 1929, everything changed when the German Reichsmarine laid down the keel of the first, an armored ship (in German, Panzerschiff). They claimed it displaced 10000 LT, following the Treaty of Versailles restrictions; it was actually at least 25% bigger, but this was not known at the time. With two 280 mm triple turrets and a top speed of 26 kn, this ship outgunned every so-called heavy cruiser with their 203 mm guns intended to respect the Washington Treaty limitations concerning the caliber of cruiser main artillery and outran every battleship except the three fastest British units (the HMS Hood, HMS Renown (1916), and HMS Repulse (1916)). The Deutschland's type was commonly designated as a pocket battleship, being actually – as her German denomination well-indicated – an armored cruiser.

The French Admiralty's reaction was to prepare a draft design for a ship which would outclass the German "pocket battleship" in armament, armor, and speed. It appeared that the previous French proposals' armament might be retained and that the speed might be no more than 30 kn, but the most important feature was that the armor had to be thicker to resist 280 mm shells. These considerations lead to a planned displacement of about 23000 –, which fit the maximum displacement that the United Kingdom proposed in the naval armament limitations negotiations.

The 1930 London Naval Treaty established that the ten-year battleship-building holiday agreed at Washington would be extended for a further five years, until 31 December 1936. France and Italy were, however, authorized to build the replacement tonnage that the Washington Naval Treaty entitled them to lay down. Nevertheless, France and Italy refused to adhere to any qualitative limitations, which were mainly concerning the maximum displacement of cruisers., as France argued that construction had just started in Germany of the armor-clad Deutschland, and following the new limits' rejection by France, Italy was no longer prepared to accept new restrictions concerning battleships.

In order to establish a ceiling for new naval construction, bilateral talks took place between France and Italy, with significant encouragement from the United Kingdom; these talks began at the start of 1931, and a basis of agreement was concluded on 1 March 1931. Until 1936, both countries would be allowed to build only two battleships, each of 23333 LT. But it was not possible to go further, as the Italian Navy was not satisfied with the 23333 LT battleship Italian project, with three twin 381 mm turrets and a profile reminiscent of the ITALIAN CRUISER Pola heavy cruiser (then in construction). A complete artillery and power plant refit of the s would begin in 1933, and plans for a 35000 LT Standard displacement battleship would be going on.

Dunkerque
In 1931, the French Admiralty explicitly confirmed the choice of a 23333 LT battleship, since the 17500 LT battleship would have been too lightly armored and the 35000 LT battleship would have required technical and financial capacities that outstripped France's capabilities. This 23333 LT battleship would have had a length of 213 m and a 27.5 m beam, two quad 305 mm/55 turrets forward, three quad 130 mm Dual Purpose (DP) turrets aft, a 30 kn top speed, 230 mm belt armor, and 150 mm deck armor. However, when in May 1931 this proposal was submitted to the Parliament, the discussion lasted two months and there was much criticism, since it was difficult to understand why it was necessary to have twice the displacement of the warship to be countered and why it was not preferable to build a 35000 LT battleship. Thus, in the 1931 Estimates in July, funds were allocated only for further studies; in addition, the law had the stipulation that the final characteristics must be subject to a thorough review, the results of which would have to be submitted to the Parliament before passing any building orders.

At this point, Vice Admiral Durand-Viel, the new Chief of Staff of the French Navy from January 1931, requested further studies for upgrading the main artillery caliber – from 305 mm to 330 mm – to outgun the Italian battleships. This upgrade resulted in a displacement increase to 26500 LT, a 2 m length increase, a 2.5 m beam increase, a slight maximum speed reduction to 29.5 kn, the substitution of 330 mm/52 guns for 305 mm/55 ones, two more double 130 mm DP turrets, and a slight thickness increase in the armored belt and deck armor. In early 1932, the project was approved by the Parliament committees, and the Minister of Defence (François Pietri) successfully included it in the 1932 Estimates. So emerged the FRENCH BATTLESHIP Dunkerque, which was ordered on 26 October 1932 and laid down on 24 December 1932.

After the Deutschland, the GERMAN CRUISER Admiral Scheer was laid down in June 1931 and the GERMAN CRUISER Admiral Graf Spee was laid down in October 1932. Consequently, the French Navy asked to quickly have a second ; she was included in the 1934 Estimates.

Facing the Scharnhorst and Littorio


Originally, the Deutschland class was intended to have six ships. On 14 February 1934, two more German battleships were ordered; officially these were the fourth and fifth Deutschland-class units, as the Third Reich had not yet denounced the Treaty of Versailles. However, for several years there were discussions about their definitive characteristics, as the Dunkerque's starting construction resulted in an upgraded pocket battleship design. Finally, the new ships emerged as the only other class – the – of small battleship (together with the Dunkerque class); these were to be faster than the 1920s battleships, with a displacement substantially under the Treaty of Washington limits. Heavier than the Dunkerque-class battleships 31800 LT with the hull dimensions of the (projected in 1915), they were strongly armored with a 350 mm belt and deck armor equivalent to the later  and  battleship classes. However, they were only armed with nine 280 mm guns, the same caliber as the Deutschland class. A heavier caliber had been considered for the main artillery, and was preferred by Adolf Hitler, since the Dunkerque-class battleships were armed with 330 mm guns. But when these ships' final design was about to be settled, Germany was negotiating the 1935 Anglo-German Naval Agreement, and the British Government was pressing very strongly for limits on the battleship main artillery caliber. Therefore, an improved gun (28 cm SK C/34), with a longer barrel and higher muzzle velocity but the same 280 mm caliber, was reluctantly chosen. The GERMAN BATTLESHIP Gneisenau was laid down on 6 May 1935 and the GERMAN BATTLESHIP Scharnhorst on 15 June 1935.

Since the French Navy ship designers thought that the Dunkerque-class battleships' armor was able to resist 280 mm caliber shells, they would not have needed to design a heavier battleship class. But Italy believed the new French battleships broke the balance between the French and Italian battleship fleets in the Mediterranean Sea. Italy thus designed new battleships, which were intended to counter not only the Dunkerque-class battleships but also the more heavily armed British Mediterranean Fleet battleships. Duce Benito Mussolini announced on 26 May 1934 the decision of Italy to fully use the right to build battleships granted in the naval limitation treaties. Some days later, the Stefani news agency announced the laying down of two 35000 LT battleships, armed with nine 381 mm guns; in October 1935 these received the names of ITALIAN BATTLESHIP Littorio and ITALIAN BATTLESHIP Vittorio Veneto.



The time had come to build the first French 35000 LT battleship. But time was missing to create a design for a truly new heavier battleship class. The French Navy Board (the Conseil Supérieur de la Marine, the French equivalent to the British Board of Admiralty) unanimously recommended on 25 June 1934 to leave the 1934 naval building plan unchanged, and to order the building of a new Dunkerque-class battleship with improved vertical (belt) armor: the FRENCH BATTLESHIP Strasbourg's laying down was ordered on July 16, 1934.

Eight days later (on 24 July 1934), the French Navy Board set the new French battleships' specifications as follows:
 * Standard displacement: 35000 LT
 * Main armament: eight or nine 380 mm or 406 mm guns
 * Secondary armament: capable of fire against both surface targets and long-range anti-aircraft fire
 * Maximum speed: 29.5 –
 * Armor: belt 360 mm; upper armored deck 160 mm; lower armored deck 40 mm; underwater protection as with the Dunkerque

Thirteen months later, the Service Technique des Constructions navales (S.T.C.N.) – the French equivalent of the Department of the Director of Naval Construction in the Royal Navy – established a definitive project which was submitted to the Minister on 14 August 1935 and adopted on 31 August, and the Richelieu was laid down on 22 October 1935. By this, France was breaking the Washington Treaty and the 1930 London Treaty, since 88000 LT of new battleships (instead of 70000 LT) had been ordered since 1922 and before 31 December 1936. However, on 18 June 1935 the Anglo-German Naval Agreement had been signed between the United Kingdom – without consulting France – and the Third Reich, canceling de facto the Treaty of Versailles limitations concerning the displacements of the various types of warships and allowing Germany to build a war navy within the limit of 35% of the Royal Navy's total tonnage. Having lost the hope of being able to counter both the German and Italian navies, as was allowed by the Versailles and Washington Treaties, France concluded that the Dunkerque-class battleships were the answer to the Scharnhorst-class battleships and the Richelieu-class battleships the answer to the s.

Germany went a step further, laying down two new battleships, the Bismarck in November 1935 and the GERMAN BATTLESHIP Tirpitz in June 1936. These ships, strongly armored as their protection absorbed more than 40% of their standard displacement, with a very large beam of 36 m, got a very classic design, eight 380 mm guns in double turrets (two forward and two aft) and the secondary anti-ship artillery as six double 150 mm turrets on the sides. Their powerful anti-aircraft artillery in sixteen 105 mm guns in eight double turrets, plus numerous 37 mm and 20 mm mountings, controlled by six high-angle directors was unmatched anywhere; officially declared as 35000 LT, their displacement was actually more than 42000 LT standard and even nearing 50000 t full load. The French answer was the laying down of the second Richelieu-class battleship, the FRENCH BATTLESHIP Jean Bart, in December 1936.

Design
The Richelieu class had a planned standard displacement of 35,000 tons, equal to the Washington Treaty limit, with a main armament of eight 380 mm guns in two quadruple turrets. Three ships in two subclasses were laid down, all of these had the main turrets in forward superfiring positions, while a fourth unit was planned with one turret forward and the other aft. There were also differences between subclasses in the secondary artillery and the aircraft installations planned to be fitted, as well as minor differences between the Richelieu and the Jean Bart resulting from the latter ship's completion, ten years after the former one's.

Richelieu and Jean Bart
Vice Admiral Durand-Viel, the Chief of the Navy's General Staff, was very concerned about continuity between the Richelieu battleship class and the preceding Dunkerque battleship class (whose lead ship had been ordered only two years before), in order to reduce to a minimum planning and construction delays and to create homogeneous combat groups. It was therefore envisaged a similar main and secondary artillery disposition.

Main artillery
The French Navy Board had indicated in July 1934 a minimum caliber of 380 mm – dictated by the Italian Navy's choice – and a maximum caliber of 406 mm – the Washington Treaty limit. For the number of guns, eight was the minimum for efficiently spotting salvos ; this was one reason the Italian Navy had not been satisfied by the 23300 LT battleship project of 1931, which had only six 381 mm guns. The maximum of nine guns corresponded to a battery of three triple turrets, as announced by the Stefani News agency for the new Italian battleships.

An arrangement of two quadruple turrets would save more than a quarter of the turret armor weight (as compared to four double turrets), while retaining the same firepower, but it was quickly determined that the 380 mm caliber was the largest feasible for a quadruple turret. With a 106 ft beam and 406 mm guns, the Nelson-class battleships had accommodated only triple turrets. But on the Dunkerque, with a 31.10 m (102.25 ft) beam and 330 mm guns, the four barrels of each turret were not mounted independently (in separate cradles) because this would have meant an unduly large barbette diameter. For this reason the right and left pairs of barrels were placed in a single common mount each. However, the fore and aft main quadruple turrets of the British King George V-class battleships will have independent mounting, as these ships will have nearly the same beam, 103 ft versus 102.25 ft (31.10 m), and 1 in more for the main guns caliber, 14 in versus 13 in, than on the Dunkerque.

The quadruple turret's major drawback was the risk of taking a single unlucky shot which would destroy one turret and cripple half the main battery; to help prevent this, the Dunkerque-class battleships' quadruple turrets had been divided internally, with a 25 - 40 mm bulkhead to localize damage. This method has been effective at Mers-el-Kebir, when the first British 381 mm shell striking the Dunkerque ultimately hit the second 330 mm turret; this killed all crew in the turret's right half, but the left half remained operational.

But the all-forward arrangement of two quadruple turrets, and more broadly the proximity between the two main artillery magazines (one for each turret), induced the greatest risk: one hit could potentially cripple the entire main battery, or even cause the ship's loss from an ammunition explosion. On the Dunkerque, to avoid this risk the forward turrets had been positioned 27 m apart from one another, further apart than on the Nelson-class battleships. Even so, the French Navy studied various other solutions, with three turrets (one quadruple and two double, two triple and one double, or three triple). In every case, with three turrets there would have been a weight excess in comparison with two quadruple turrets, and in consequence a propulsion plant power reduced to 100000 hp and a speed loss of 2.5 kn, for a small benefit of distributing the main armament over a greater length. Therefore, following the proposal of STCN's head, the Chief of Navy General Staff chose as early as November 1934 the all-forward arrangement with two quadruple turrets.



The solutions used on Dunkerque-class battleships were retained on the Richelieu, in a scaled up version: an all-forward arrangement, in two 2476 t 1936-model quadruple turrets built by Saint-Chamond, weighing 3096 t together with the barbette. It weighed nearly 1000 t more than the roughly 1500 t quadruple turrets of the Dunkerque or the triple turrets of the Littorio.

Each Richelieu turret was divided in two half turrets, by a 25 mm to 45 mm bulkhead. The guns, in the half turrets, were in pairs, and although each gun was in a separate cradle, the relative movement of the guns of each pair was limited. The guns were so close (1.95 m, only 0.30 m more than on the Dunkerque) that a wake effect between shells fired simultaneously by a half turret lead to an excessive dispersal, which was not corrected before 1948 on the Richelieu. The turrets were positioned 32.5 m apart from one another, 3.70 m more than on the Dunkerque.

The weight of one barrel was 110 t. This weight was: less than the 181 t barrel on the Yamato, or the 130 LT barrel on the Nelson; nearly the same weight as the 112 t barrel on the Nagato, the 109 t barrel on the Bismarck, the 107 LT barrel on the Iowa, the 102 t barrel on Littorio, or the 97 LT Queen Elizabeth barrel; and more than the 80 LT King George V barrel.

The maximum angle of elevation of guns on the Model 1936 turret was 35°. With a 830 m/s muzzle velocity, the maximum range was theoretically 41500 m, practically 37800 m. The rate of fire was from 1.3 rounds per minute to 2 rpm. The maximum horizontal turning speed was 5°/s, and the maximum elevating speed 5.5°/s.

The 380 mm shell was an Armor Piercing Capped (APC) shell, registered in the French Navy as Obus de Perforation (OPf). The OPf Model 1935 was a further development of the 330 mm OPf Model 1935, in use on the Dunkerque, except that its molded base formed a boat tail that assisted in keeping the shell stable in flight. The 380 mm shell was 1.905 m long and weighed 884 kg, less than the 406 mm USS Massachusetts (BB-59)' shell (1224 kg), that glancingly hit the Jean Bart at the battle of Casablanca (1942), and some kilos more than the weight of the 381 mm shells of HMS Barham (04) or HMS Resolution (09) (875 kg), that lightly damaged the Richelieu at the battle of Dakar (1940).

The OPfK Model 1935 incorporated a dye bag and fuze (dispositif K) to color not only misses but hits, thereby facilitating spotting for ships operating in formation while in combat. No High Explosive (HE) variant of the 380 mm shell was originally provided. A total of 832 APC shells were intended to be provided, slightly fewer than for the Dunkerque-class battleships (896 rounds).

Remote Power Control (RPC) was to be fitted for both horizontal turning and elevation; however, the failure of the Sautter-Harlé-Blondel system fitted on the Dunkerque-class battleships resulted in a loss of confidence in the application of this technology to heavy armored turrets, and it was never fitted.

Secondary artillery


The French Navy had been first to fit a dual-purpose (DP) battery on a battleship, in the early 1930s; seven years later, with the shortcomings seen with the 130 mm and 152 mm DP turrets and 37 mm twin automatic AA mountings, the solution of having a low-angle secondary battery and a high-angle tertiary battery was a feature of the new battleships in construction, as in the Italian and German navies.

For the secondary artillery, all early projects kept the 130 mm caliber, in five quadruple Dual-Purpose turrets, at the same position as on the Dunkerque-class battleships, but with quadruple turrets amidships, instead of double turrets. A tertiary anti-aircraft 75 mm zénithaux battery was considered, to complement the early design sketch's 130 mm DP battery.

Since at the time torpedo surface attacks were considered more damaging than aircraft bombing, a heavier caliber was required for the anti-ship battery. Since the Nelson-class battleships, the Royal Navy had adopted a six 152 mm double turrets battery as the secondary artillery on battleships. The Kriegsmarine had chosen 150 mm guns on the GERMAN BATTLESHIP Scharnhorst, and the Italian Navy was fitting the 35000 LT battleships with 152 mm caliber guns. It was decided to use triple 152 mm turrets, as fitted on the most recent light cruisers, the FRENCH CRUISER Émile Bertin and the s that were then being built. The S.T.C.N. proposed three solutions: five 152 mm turrets and six 75 mm single mountings; or four 152 mm turrets, without the fifth turret (central axial); or with two center line aft turrets in a superfiring position, and eight 75 mm single mountings, but it was difficult to install this AA battery while keeping it out of the blast effects of the main and secondary batteries.

The French Naval Board in April 1935 resolved to fit the Richelieu with five 152 mm turrets in the same placement as for the 130 mm battery on the Dunkerque. It was decided that these 152 mm turrets had to be dual-purpose, and that the tertiary 75 mm AA battery had to be abandoned, as the substitution of 152 mm DP turrets, weighing 306 t to the 130 mm turrets, weighing 200 t, was inducing an weight excess of about 530 t. It was also decided to install a new weight-saving propulsion plant, generating the same power of 150000 hp, but using more compact Sural boilers, than those fitted on the Dunkerque. It was therefore possible to reduce the number of boiler rooms from three to two, which allowed a reduction of the armored belt's length of nearly 5 m, and consequently of its weight. As another weight-reduction measure, the armored belt's thickness was reduced from 360 mm planned to 330 mm and its inclination increased from 11°30' to 15°24' to compensate for the thickness reduction. The armor thicknesses of the longitudinal bulkheads, conning tower, and turrets and barbettes of the 152 mm guns were also reduced.

The triple 152 mm Model 1936 Dual Purpose turret was a further development of the 152 mm Model 1930 Low-Angle turret. The guns, mounted on separate cradles, were 1.85 m apart. The horizontal turning speed was 12°/second, and the elevation speed was 8°/s. The guns' maximum elevation was 90°, with loading at every elevation theoretically possible. The muzzle velocity was 870 m/s. The shells to be used against sea targets were Semi Armored Piercing (SAP) shells with a dye bag, registered in the French Navy as OPfK Model 1931, weighing 56 kg, or 57.1 kg for the OPfK Model 1937. Against aircraft, the 152 mm/55 Model 1930 guns would be firing High Explosive (HE) shells, registered as OEA (Obus Explosif en Acier) Model 1936 and weighing 54.7 kg, or 49.3 kg for the OEA Model 1937. Starshells, registered as OEcl (Obus Eclairant) Model 1936 and weighing 47 kg, were to be provided for the amidships turrets. The rate of fire was 6.5 rounds per minute, against sea targets, and 5 rpm against aircraft. The maximum range against sea targets, with a 45° elevation, was 24500 m. Full RPC was fitted. On the Richelieu, the planned ammunition load was 2000 SAP shells, nearly 1000 HE shells, and 650 illuminating shells, for the three triple turrets fitted.

The 152 mm Model 1930 Low-Angle turret proved to be highly satisfactory, at least comparable to the German single or twin 150 mm gun turrets, or the Italian triple 152 mm turrets Model 1934 or 1936. But for anti-aircraft purposes, the 152 mm Model 1936 turret was thought to be complex and fragile, with a too-slow rate of fire against rapid-moving aerial targets, with a deficient RPC, and with jamming in loading at angles greater than 45°. These problems were probably due to the too-great weight, 228 t without the barbette, of the 152 mm DP Model 1936 turret; this was nearly 56 t heavier than the 172 t 152 mm Model 1931. During WWII, there were no other 152 mm guns used as an anti-aircraft battery; however, they were successfully used post-war in two U.S. Navy cruisers and three s of the Royal Navy, albeit with much better RPC and fire-control devices than the pre-WWII French ones.

At the war's very beginning (in November 1939), it became evident that the projected 37 mm ACAD Model 1935 (automatic anti-aircraft twin) mountings would not be provided in time for the Richelieu's completion; thus, a drastic revision of the AA battery was needed. The midship 152 mm turrets had to be canceled, and twelve 100 mm/45 Model 1930 guns in six twin 100 mm mountings, CAD Model 1931, would instead be fitted, as they had been on the last 10000 LT Treaty cruiser (the FRENCH CRUISER Algérie). To respect the priority of completing the Richelieu first, four mountings had to be removed from the reconstructed battleship FRENCH BATTLESHIP Lorraine, and two from a battery near Marseilles. The 152 mm amidships turrets were not even mounted on the Jean Bart; nor were barbettes installed. The 100 mm mountings were fitted on Richelieu in April–May 1940.

The 100 mm CAD Model 1930 turrets were dual-purpose. SAP shells (100 mm OPf Model 1928, weighing 15 kg) would be used for sea targets, with a muzzle velocity of 765 m/s and a 15800 m maximum range, but only 10 rounds per gun were intended, due to the belief that the anti-ship fire would be mainly done by the stronger 152 mm guns. HE shells (100 mm OEA Model 1928, weighing 135 kg) would be used on aerial targets, with a muzzle velocity of 780 m/s and a 10000 m ceiling (at the 80° maximum elevation). The rate of fire was 10rpm. Illuminating shells (100 mm OEcl Model 1928) were provided to replace the 152 mm OEcl Model 1936. The 100 mm guns proved to be the only reliable arms of the Richelieu until 1942, due to the uncompleted or obsolescent fire control of the 380 mm and 152 mm batteries.

Anti-aircraft light artillery
For short range anti-aircraft defense, the French Navy had planned to develop for the Dunkerque-class battleships an automatic version (37 mm ACAD Model 1935) of the 37 mm semi-automatic anti-aircraft with twin mountings (CAD Model 1933); the latter had a theoretical firing rate of 30 to 40 rpm. Hand loaded using a six-round box magazine, the actual firing rate was 15 to 20 rpm; in the same time period, the British Pom Pom gun and the Swedish designed Bofors 40 mm/L60 gun had a 120 to 200 rpm firing rate. Therefore, the 37 mm ACAD Model 1935 was expected to have a firing rate of 120 rpm or above. However, in 1940 only a prototype ACAD mounting (designated Model 1936) was tested (aboard the old patrol sloop Amiens; it was apparently successfully used during the Dunkirk evacuation).

Six 37 mm ACAD Model 1935 mountings would have been fitted, four abeam the after funnel superstructure, and two abeam turret II. Four fire control systems, equipped with a 2 m rangefinder and linked to the mountings by a RPC system driven by Sautter-Hallé electric servomotors, were intended to be installed: two for the forward mountings, abaft turret II, one deck higher, and two for the after mountings, abeam the mountings, one deck higher. This 37 mm battery would have been complemented by six or eight 13.2 mm Hotchkiss quadruple MG mountings (CAQ Model 1929) on the upper platforms of the forward and after towers.

Fire control systems
The most conspicuous difference in the Richelieu and Dunkerque profiles was the mounting of the fire control director system aft, not on a separate tower located behind the funnel, but on a kind of mack, so that the funnel opening came out obliquely aft underneath the control tower. Otherwise, the fire control system was very similar to the Dunkerque's. All the fire control systems were airtight and fitted with light steel plating against the machine gun attacks of strafing aircraft.

Three fire control systems were mounted one over the other atop the fore tower. The lowest was the A system, for the main artillery, with a 14 m triple stereoscopic OPL (Optique de Précision de Levallois-Perret) rangefinder. For the 152 mm artillery, there were two fire control systems. System 1, in the upper position, was for anti-aircraft gunnery and had a 6 m double stereoscopic OPL rangefinder. System 2, in the central position, was for anti-ship gunnery and had a 8 m double stereoscopic OPL rangefinder.

The same noteworthy weight accumulation in the fore tower top as on the Dunkerque proved to be a problem when the Richelieu was torpedoed at Dakar, as a whiplash effect on the main mast around which they were mounted provoked more serious effects on the fore tower systems than on those on the after tower, despite that the latter was nearer the torpedo explosion.

On the after tower, there was only the auxiliary system for the 152 mm artillery (system 3) with a 6 m double stereoscopic OPL rangefinder. The auxiliary (B) system for the main artillery was between the funnel and the axial aft 152 mm turret and had an 8 m double stereoscopic OPL rangefinder. Each main artillery turret was fitted with a 14 m double stereoscopic OPL rangefinder, and each 152 mm turret with a 8 m double stereoscopic OPL range finder. Two systems with 3 m OPL rangefinders provided for the flag staff were installed on the wings of the admiral’s bridge. When the 100 mm AA battery was fitted, they were replaced by systems fitted with 4 m OPL rangefinders for this battery's fire control. Two systems also fitted with 4 m rangefinders were then mounted on the navigation bridge, one deck lower. There was also a 3 m SOM (Société d'Optique et de Mécanique de haute précision) stereoscopic tactical rangefinder atop the admiral's bridge. As on the Dunkerque-class battleships, the systems provided raw target data to the transmitting station located beneath the armored decks, with continuous transmission to the director and the guns.

The lookout and target designation facilities were similar in principle to the Dunkerque's. The lower lookout station (veille basse) for close-range contacts was on platform 3 of the fore tower. The middle level (veille éloignée), for both surface and aerial contacts, was on platform 6, and the upper lookout station (veille haute), primarily for spotting torpedoes and mines, was on platform 9. For night firing, there were five 1.20 m searchlights, one atop the admiral's bridge and two on either side of the funnel structure.

Aircraft installations
As on the Dunkerque, aircraft installations (aircraft hangar, crane and two catapults, for four seaplanes) were fitted on the Richelieu's stern. The components were the same, 22 m trainable catapults operated with compressed air, which could launch a 3.5 t aircraft at 103 km/h, and a recovery crane with a capacity of 4.5 t. The aircraft were (flying boat) seaplanes of the Loire 130 type – single-engined (720 hp Hispano-Suiza 12-cylinder liquid cooled) with a 3500 kg weight, a 210 km/h maximum speed, a 165 km/h cruise speed at 1500 m, two 75 mm machine guns and two 75 kg bombs.

There were, however, differences from the Dunkerque's aircraft installations, resulting from the differing boiler placement: three side by side in each boiler room, instead of two; thus, there was only one boiler room under the funnel instead of two. Consequently, the aft 152 mm turret on the center line, turret VII, was on frame 68.85 on the Richelieu, versus on frame 44.30, on the Dunkerque, as the aft lateral secondary turrets were respectively on frame 54.45, versus 53.30. With 36.50 m on the quarterdeck between the aviation hangar and the stern on the Richelieu, instead 30 m on Dunkerque, this enabled a second catapult to be worked in, the catapults being offset to port and starboard en échelon with an elevator between them. The planes were moved on rails from the hangar to the elevator where they were placed on both catapults. Two planes were to be stowed in the 25 m hangar on the same level, wings folded and in line, instead of being placed on the two platforms of a two-tier hangar lift, and two on the catapults with wings deployed.

Protection
On Richelieu, the armor weight was 16045 t and corresponded to 39.2% of the total weight, for a 40927 t normal displacement, with 2905 t of fuel (half of full load). This figure may be compared to those given for the Dunkerque, 35.9%, or the Strasbourg, 37.3%, with a 30750 t or 31570 t normal displacement, with 2860 t of fuel (¾ of full load). A comparison with other battleships is more difficult. The figures given for the Iowa-class battleships are 18700 tons for the armor weight and 41.6% of 45,000 tons standard displacement, which corresponds for the Richelieu to more than 42% of standard displacement. For the Bismarck, the figures are 17258 tons or 17540 tons for the armor weight, and from 43.92% to 41.30%, depending on whether the percentage is calculated with 39931 tons light displacement or 41781 tons standard displacement. As all these figures are very close to one another, it is clear that they are all superior to those for earlier battleships (such as the Dunkerque) or those given for the King George V-class battleships, 12500 tons and 34.80% or for the Littorio-class battleships with 13600 t weight of armor and 36% of 37750 t standard displacement.

Armor
The armor thicknesses were as follows:
 * The armored belt, with a slope of 15°24’, was 327 mm thick between frame 51.50 and frame 182.95 and from 3.38 m above the waterline to 2.50 m under the water line. The forward bulkhead, at frame 182.95, and the after bulkhead, at frame 51.50, extended from the main deck to the 30 mm thick floor of the artillery magazines, and were 233 mm thick. The forward bulkhead thickness was increased to 355 mm between the first and second platform decks.
 * The upper armored deck at main deck level was 150 mm thick above the machinery plant and was increasing to 170 mm above the main artillery magazines. The lower armored deck was 40 mm thick and extended to frame 233, improving the protection of the forward part of the ship, left unprotected on the Dunkerque. Abaft the after transverse bulkhead, there was (at the first platform deck level) a 100 mm armored deck with angled sides in the form of a carapace above the shafts, increasing to 150 mm above the steering gear.
 * On the conning tower, the armor was 340 mm thick on the front and sides, 280 mm on the rear, and 170 mm on the roof.
 * The main turrets were protected with a 405 mm thick armor on the barbette, above the upper armored deck; 430 mm armor on the faces, inclined to 30°; from 170 mm to 195 mm on the roof; 270 mm on the turret I rear wall; and 260 mm on the turret II rear wall. This thickness on the rear walls, less than on the Dunkerque or Strasbourg with about 345 mm thickness, was due to the use of a cemented steel on the Richelieu.
 * The 152 mm gun turrets were less armored than the Dunkerque quadruple 130 mm turrets, with a 100 mm thickness on barbettes, 130 mm on the faces angled at 45°, 70 mm on sides and roof, and 60 mm on the rear.

The British King George V-class battleships and HMS Vanguard (23) had a thicker armored belt than the Richelieu (356 mm), but their turrets were less protected (330 mm), and the horizontal armor (152 mm) was equivalent, but their command spaces were only protected against shrapnel.

The U.S. Navy battleships had an equivalent armored belt (about 335 mm) to the Richelieu, on the North Carolina and South Dakota classes, and a little less thick (310 mm) on the Iowa class. The main artillery turret protection was less thick (406 mm) on the North Carolina class, equivalent (430 mm) on the Iowa class, and thicker (457 mm) on the South Dakota class. The horizontal armor was a little less thick (104 mm) on the North Carolina class and equivalent (127 mm to 165 mm) on the South Dakota and Iowa classes. The conning tower was better protected, with 406 mm on the North Carolina and South Dakota classes and with 445 mm on the Iowa class.

The Italian Littorio had a thicker armored belt (350 mm) than the Richelieu, but otherwise they were less protected, with 350 mm on the main artillery turrets, 260 mm on the conning tower, 50 mm on the upper armored deck and 100 mm on the main deck. The German Bismarck-class battleships had a thinner armor than the Richelieu on the main artillery turrets (356 mm), but thicker on the conning tower (356 mm), and equivalent for the armored belt (320 mm) and horizontal armor (80 mm to 115 mm).

Underwater protection
As on the Dunkerque, the underwater protection consisted of a sandwich of void spaces, light bulkheads, liquid loading compartments or compartments filled with a rubber-based water-excluding compound (ébonite-mousse), and a heavy internal holding bulkhead to absorb the explosion of a torpedo head.

The compartment outward of the inclined armor belt had a maximum depth of 1.5 m, and had a filling of ébonite mousse. Inward of this compartment, there was a 18 mm bulkhead, enclosing a void compartment 0.9 m deep, then an oil fuel bunker 3.4 m deep (0.5 m less than on the Dunkerque), then a 10 mm bulkhead, containing a void compartment 0.67 m deep, backed by a 30 mm torpedo bulkhead of special steel. The maximum width was around 7 m. The reduction of 0.5 m comparing with Dunkerque was necessary to accommodate three boilers side by side in the boiler rooms.

This figure of 7 m width was impressive, compared with the 4.10 m on the King George V, 5 m on the Scharnhorst, or 6 m on the Bismarck. The Italian Littorio-class battleships had a peculiar underwater protection system, designed by the Italian chief designer, Generale Ispettore del Genio Navale Pugliese, which incorporated a 3.8 m diameter cylindrical expansion space. During the British aircraft attack on the Italian battleship fleet in Taranto, on 11 November 1940, this did not prevent the sinking of the Littorio in shallow water. But the Achilles' heels of battleships facing torpedo attacks were their vitals that could not be protected, such as the shaft of the Richelieu at Dakar, on 8 July 1940, or the rudder of the Bismarck in May 1941.

Propulsion
The French designers of the Richelieu had various constraints: a 33.5 m beam to accommodate the barbettes of four 380 mm gun turrets, a 245 m long hull, limited by the length of the Navy shipbuilding infrastructure, and thus a length/beam ratio of 7.3. All this required machinery generating 150,000 hp to reach the 30 kn requested by the French Navy Board. It was then the greatest mechanical power installed on a battleship. It would be surpassed only on U.S. Navy Iowa-class battleships in 1943–1944. An equivalent speed had been reached with less power (144,000 hp) on HMS Hood (51), but with a 262 m hull, a 42000 t displacement, and a ratio length/beam of 8; this was done without shipbuilding restraint or any displacement Treaty limit. All British or U.S. battleships built in the late 1930s, having to respect the 35,000 tons displacement limit, had a speed of 29 kn – the King George V class – or 28 kn – North Carolina or South Dakota classes; they were 225 m or 215 m long, with a propulsion plant developing respectively 110,000, 120,000, or 130,000 hp. The Italian Littorio-class battleships reached 30 kn with a 230 m hull and 140,000 hp. The German battleship Bismarck had a 29 kn speed with 138,000 hp, and reached 31 knots with forcing for 150,000 hp, with a length/beam ratio of only 6.9 as she had nearly the same hull length as the Richelieu, but a wider beam (36 m).

The propulsion of the Richelieu was assured by six Indret boilers, and four Parsons turbines. The boilers were of a new type, the so-called suralimenté meaning pressure-fired (and thus the abbreviation of Sural) boilers. These boilers were operated at a pressure of 27 kg/cm² (384 lb/in²) at 350 C, as on the Dunkerque, but forced circulation and pressure firing resulted in steam production per cubic meter well in excess of conventional boilers (14.4 kg/m³). They were 6.30 m long versus 5.33 m in on the Dunkerque, 4.65 m height versus 5.34 m, and moreover 4.50 m wide versus 6.50 m. Thus, due to the 2-meter greater beam of Richelieu, it was possible to install three boilers side by side in two boiler rooms, instead of three rooms as on the Dunkerque. Boiler room 1 was underneath the fore tower, with, from starboard to port, boilers #10, #11, and #12, followed by the forward engine room housing the geared turbines for the wing shafts. Boiler room 2 (directly underneath the funnel), with boilers #20, #21, and #22, produced the steam for the center shaft turbines in the aft engine room. A 18 mm bulkhead separated the forward engine room from boiler room 2, dividing the machinery into two independent units.

In each Engine Room, there were two sets of turbines, each driving a four-bladed propeller with a diameter of 4.88 m. Each set comprised a single High Pressure (27 kg/cm²) turbine, a Medium Pressure (10 kg/cm²) turbine, and two Low Pressure two-flow rotor turbines (4 kg/cm² and 1.25 kg/cm²). Four turbo generators, each of 1500 kW, were used; two were in the forward engine room, and the other two in a separate compartment directly abaft the main machinery spaces, adjacent to the magazines for the after 152 mm turrets.

The maximum fuel load for peace-time cruising was 5866 t, but in wartime this figure was reduced to 4700 t to maximize the underwater protection system's effectiveness, since filling the liquid loading compartments to the brim created additional pressure on bulkheads instead of absorbing the pressure of explosion. The radius of possible travel was 9850 nmi at 16 kn, 8250 nmi at 20 kn, and 3450 nmi at 30 kn.

During speed trials, in April 1940 developing 123,000 hp 30 kn were maintained with near 42000 t displacement, and in June 32 kn were maintained for 3 hours and 30 minutes, with 43800 t displacement and 155,000 hp, and 32.68 kn were reached with 179,000 hp forcing.

1938 Supplementary Program Battleships
In 1937, Italy ordered two more s, to be laid down in 1938. The French reaction was to order two more Richelieu-class battleships, with an improved design since the limited French naval building capacity required some delays before laying these units down.

The second London naval disarmament conference's failure had marked the end of international naval armament limitation policy. Japan had withdrawn from the conference on 15 January 1936; Italy also declined to sign the Second London Naval Treaty. A so-called "escalator clause" had been included at the American negotiators' urging, allowing the signatory countries of the Second London Treaty (France, the United Kingdom and the United States) to raise the battleship main battery caliber limit from 14 in to 16 in, and the limit for battleship displacement from 35,000 tons to 45,000 tons, if Japan or Italy still refused to sign after April 1, 1937. Ultimately the U.S.A. adopted 16 in guns for their new fast battleship classes, whereas the United Kingdom chose to respect the original Second London Naval Treaty limitations for the King George V-class battleships. Germany was not concerned, as she had not been invited to the second London naval disarmament conference, but officially the battleships GERMAN BATTLESHIP Bismarck and GERMAN BATTLESHIP Tirpitz had 380 mm guns and 35,000 tons displacements. France decided to respect the limitations of 35,000 tons and 380 mm as long as no continental European power had broken them. Bearing such considerations in mind, the new Chief of the Navy General Staff (Chef d'Etat-major Général de la Marine), Admiral Darlan, ordered in December 1937 a study of new designs for two battleships, especially since the Dunkerque's trials were showing problems with her design, especially her all forward quadruple turret main artillery and her dual purpose (anti-aircraft and anti-ship) secondary artillery of relatively light caliber.

Three projects were studied, the first (project A) with the same quadruple arrangement forward as the Richelieu, but different secondary artillery arrangements, the second (project B) with one quadruple turret forward and one quadruple turret aft, the third (project C) with two fore triple turrets and one triple turret aft, in every case with a 380 mm caliber. Project C lead to an excess displacement of 5,000 tons over the limit of 35,000 tons, so it was not proposed to the Chief of the Navy General Staff.

In June 1938, the French Admiralty's choice was tightly linked with the need to maximally use the shipyards where very large ships could be built. The Salou #4 graving dock in the Brest Navy Yards was intended to be ready for building a new battleship in January 1939, when the Richelieu will have been be floated out, as all other building for large ships were in use. On the new Caquot dock, in the Penhoët Shipbuilding Yards in Saint-Nazaire, the Jean Bart was being built and expected to be floated out in late 1939-early 1940. In the same shipbuilding yard, on the #1 slipway where the SS Normandie and Strasbourg had been laid down, the FRENCH AIRCRAFT CARRIER Joffre was to be built from November 1938 till 1941. Consequently, it was not reasonable to keep the Salou building dock empty for at least six months, waiting to start building a Project B design battleship which necessitated at least one year to come up with definitive drawings after it had been ordered. Therefore, the Project A design was chosen for the first battleship to be laid down in the Salou building dock. The Caquot dock could then be used for the second battleship to be laid down.

Admiral Darlan chose project A variant 2 for the first ship of the Richelieu class' second pair to be laid down; she received the name of Clemenceau. He chose project B variant 3 for the second ship – a design in which he was much involved – and named her Gascogne after the French area where he was born, meaning also that this new battleship was a transition to a new battleship class again named after provinces.

When in the summer of 1939 the French intelligence services warned the French Admiralty that the keels of two German battleships had been laid down, supposed to be of 40000 t tonnage and with 406 mm guns, but actually Plan Z H-39-class battleships, it was decided to design a ship free of the limitations of 35000 LT and 380 mm. Based on the studies of 1938's Project C, new battleship designs emerged that led to the so-called Province or later s that were never even ordered.

Clemenceau
On the Clemenceau, the main artillery arrangement was as on the Richelieu and Jean Bart. But the 152 mm battery would have consisted of four triple turrets of 152 mm caliber, two amidships (one on each side), and two aft in superfiring positions. Admiral Darlan, Chief of the Navy General Staff, thought that the three 152 mm turrets aft on the Richelieu were a mistake, since two turrets in centerline positions would provide the same broadside of six guns and saved nearly 300 t, allowing having six more 100 mm AA mountings. Two of these mountings would have been positioned in front of the fore tower in superfiring position abaft the fore 380 mm turrets, and four other ones, abeam the funnel and the axial aft 152 mm turrets, and abaft the 152 mm amidships turrets. As the firing arcs of the 152 mm turrets amidships were intended to be mainly directed forwards, the 100 mm AA battery would have been shielded enough from their blast effects. Moreover these 100 mm turrets would have been fully enclosed, with a 30 mm plating against shrapnel. This new model of turrets was known as the 100 mm CAD Model 1937, and also as the so-called «mine sweeper sloop type» since it was intended to be installed on the and  minesweeper sloop classes; it was also intended for the  destroyer class too, and as a secondary battery on the De Grasse cruiser class, to be commissioned in the late 1930s or early 1940s.

But this new arrangement had some difficulties. The second aft turret in superfiring position had a greater part of its barbette above the main armored deck, and thus needed more 100 mm plating. Thus, the 152 mm turret faces' armor thickness had to be reduced to 116 mm– instead of 130 mm – the armored belt's to 320 mm, and the main turrets' rear plates' to 250 mm. The auxiliary fire control system abaft the funnel, for the 380 mm battery, was to be mounted about 2.5 m higher than in the Richelieu, requiring a greater funnel height. Two more fire control systems with OPL 5 m stereoscopic rangefinders, for the 100 mm AA battery, would have been installed on the sides of the fore tower. To save weight, particularly in the heights, the anti-ship fire control system for the 152 mm battery would have not been installed, but the two remaining fire control directors for the 152 mm battery, on the aft tower and on the fore tower in the upper position, would have been fitted with a stereoscopic 8 m OPL rangefinder. With these arrangements, the anti-ship and anti-aircraft artillery on the Clemenceau would be better than that originally intended for the Richelieu and Jean Bart.

As a last consequence, the center line arrangement of the 152 mm turrets aft placed the extreme aft turret (turret VI) in frame 54.45, while on the Richelieu the extreme aft turret (turret VII; in the center line position) was on the 68.85 frame. Thus, the aviation hangar would have been shortened by nearly 15 m. But the aft lateral turrets' removal, which were on the Richelieu precisely on the frame 54.45, would allow having a broader hangar. The two sea planes intended to be sheltered, wings folded, in the hangar would have been accommodated side by side instead of in line. Otherwise, the aviation facilities would have been the same as on the Richelieu.

The short-range anti-aircraft battery would have been six twin ACAD Mode 1935 mountings, installed with their fire control systems on nearly the same positions as on the Richelieu, but the two forward mountings were lightly abaft the turret II barbette, and for the four after mountings one deck higher. New quadruple 37 mm zénithaux mountings, intended to be used against dive-bombing aircraft, would have been installed on each side of the quarterdeck near the aviation hangar.

Gascogne
The most conspicuous change with the Gascogne would have been the return to a main artillery arrangement with a quadruple 380 mm gun turret aft. This rearrangement of armament also would result in a shift of superstructures forward so that these were now mounted almost exactly midships and no longer at a considerable distance aft of the midship position as in the first Richelieu-class units.

The Gascogne's secondary artillery would have been three triple turrets of 152 mm caliber, all on one axial line, two in a superfiring position forward and one between the funnel and the aft 380 mm turret, which freed up the sides of the ship for eight anti-aircraft dual mountings of 100 mm caliber. As the 152 mm guns' magazines would have been be near the main artillery turrets' magazines, which would increase risks, the 152 mm turrets' armor had to be improved. First, in July 1938 it was proposed to increase the turret armor thickness to 190 mm on the faces (instead of 130 mm), 120 mm on the roofs, and 100 mm on the sides (instead of 70 mm); the barbettes would have remained at 100 mm. In February 1939, a rebalancing was proposed with a thickness of 150 mm for the barbette, 155 mm for the turret faces, and from 135 mm to 85 mm for the turret sides. A thinner upper armored deck had been considered, reducing its thickness to around 145 mm, instead of around 160 mm, but there is no proof that such a decision was actually taken, beyond a S.T.C.N. recommendation dated 5 March 1938.

In the December 1938 designs, aircraft installations were intended to be fitted at the ship's center, with trainable catapults between the fore tower and the funnel, and a hangar at the after tower's base, but problems with positioning the 100 mm AA battery too near the main and secondary batteries resulted, in February 1939, in again positioning the aircraft installations at the ship's stern. A single axial catapult would have had its pedestal countersunk in the quarterdeck, with an internal hangar in a recess under the first deck and a lift to hoist the seaplanes to the first deck level in order to avoid the blast effects of the rear 380 mm turret firing, which also would have required positioning one deck higher the aft 381 mm turret, on the Vittorio Veneto-class battleships. The hull seaplanes would have been of a new twin-motored type, the Farman/NCAC NC 420, with an increased endurance (1,350 km at 240 km/h, versus 1,125 km at 150 km/h for the Loire 130). Its prototype was almost complete in June 1940 but never flew. Two seaplanes would have been stowed in the hangar in line, and a third one would have been parked on rails on the quarterdeck, to the aviation hangar's starboard.

Thus, the eight 100 mm CAD Model 1937 turrets would have been positioned in four groups of two, amidships, in the four corners of the superstructure. Each group of two turrets would have had a fire control system, with a 5 m OPL rangefinder; for the forward groups this would be on each side of the fore tower, and for the aft turret groups it would be atop the after tower. Thus, the backup system for the 152 mm battery, would have been eliminated, and the secondary battery's fire control direction insured by the upper system in the fore tower for anti-ship gunnery and by the 100 mm battery's systems for anti-aircraft gunnery.

The six 37 mm AA Model 1935 mountings would have been installed with four mountings abeam the forward turret (two on the forecastle and two a little abaft, one deck higher), with their fire control systems amidships between the fore and the aft tower, and the two after mountings would have been positioned abeam the after superstructure with their fire control systems a little forward and one deck higher. The 37 mm zénithaux quadruple mountings would have had to be repositioned amidships between the fore and after towers, because on the quarterdeck – as on the Clemenceau – they would have been excessively exposed to the blast from the aft main turret.

Richelieu


The keel was laid down on 22 October 1935 in Brest. The hull was floated out on 17 January 1939. Richelieu then left the Salou graving dock, to be armed in one of the Laninon docks at the Brest Navy Yards. The bow and the stern, built separately, were attached there since the Salou graving dock was only 200 m long. Mechanical trials began at the end of March 1940.

In April 1940, Richelieu went to sea for the first time. In late May and mid-June, the Commanding Officer, Captain Marzin carried out speed and gunnery trials, reaching 32 knots, and firing a few shots from her main and secondary batteries. Due to the advance of German troops, Richelieu hastily left Brest bound for Dakar on 18 June 1940, having on board 250 shells but only 48 powder charges for her main battery. Escorted by the s FRENCH DESTROYER Fougueux and FRENCH DESTROYER Frondeur, she reached Dakar on 23 June 1940.

Dakar, under Vichy's orders


As the local political conditions seemed very dubious regarding the acceptance of the armistice between France and Germany, Captain Marzin decided to proceed to Casablanca two days later, shadowed by a powerful British battle group. The Richelieu was sent back to Dakar by the French Admiralty on 28 June where she moored in the outer roadstead, east of Dakar harbour and north of the island of Gorée, protected only, on the high sea side, by a line of five seized British flagged freighters. Her anti-aircraft artillery was very weak. The 152 mm turrets could not fire on aerial targets, as the corresponding uppermost rangefinder on the fore tower had not been put in service; moreover, shells and powder charges were lacking. Only the six 100 mm turrets were usable. The short range anti-aircraft artillery had only four double 37 mm semi-automatic mountings, four quadruple 13.2 mm Hotchkiss machine guns, and two twin 13.2 mm machine guns.

The 22 June 1940 armistice prompted British anxiety that the French Navy would be taken over by the Axis Powers. This led to attacks from the Royal Navy against the French warships (Operation Catapult): to seize them (in British harbors), sink them (at Mers el-Kebir), or intern them (at Alexandria). During the night of July 7 to 8, five days after the attack on the French fleet at Mers-el-Kebir, a team from HMS Hermes (95) attempted to damage the Richelieu with depth charges moored under her stern, but they did not explode. In the morning, Swordfish bombers from the Hermes torpedoed Richelieu below the armored deck. This caused a 40 ft long hole, and disabled the starboard propeller shaft; flooding caused her stern to touch bottom. One torpedo is likely to have hit the depth charges moored during the night. The crippled battleship was pumped out after a few days and made seaworthy for emergencies, and moored inside the Dakar harbor.

On 24 September, the Richelieu took part in the defence of Dakar against British and Free French forces. There was a gunnery duel between Richelieu and the British battleships HMS Barham (04) and HMS Resolution (09): HMS Barham was hit twice by the shore batteries manned by ratings from the Richelieu. In the engagement the Richelieu was struck by two 15 in shells causing no serious damage; there were 250 near misses. The Richelieu was damaged in the battle the first time her main battery fired: a 380 mm shell blew back and disabled two guns in the #2 main turret; this was thought to be from the use of the wrong propellant type. There was no more firing during this day with the #2 main turret. On the day after, the #1 main turret was used instead. The propellant was changed to the SD19 propellant of the reconditioned Strasbourg powder charges; however, this caused serious problems regarding range-finding. In 1941, an inquiry commission under Admiral de Penfentenyo de Kervérégen concluded there had been a mistake in the shell base design. During the two days, the Richelieu fired a total of 24 rounds. No hits were recorded. The third day, as HMS Resolution had been struck by a torpedo from a French submarine, the British and Free French force retreated.

Temporary repairs were completed in Dakar; some light anti-aircraft mountings were added, partly taken from the wreck of the destroyer FRENCH DESTROYER Audacieux (severely damaged by a heavy cruiser during the battle). During the first months of 1941, the Richelieu was the first French battleship to be fitted with an early French radar (designated as "electro-magnetic detection"). On 24 April 1941, the Richelieu could sail at 14 kn on three engines, the fourth propeller having been removed. During July 1941, three Loire 130 seaplanes were shipped.

On the Allies' side


After French forces in Africa joined the Allies after the Allied landings in North Africa in November 1942, the Richelieu sailed for refitting at the New York Navy Yard on 30 January 1943. The three ruined barrels of the Richelieu's upper main battery turret were replaced by barrels previously fitted on the FRENCH BATTLESHIP Jean Bart, the second Richelieu-class unit, that was staying at Casablanca. The fourth barrel from the Jean Bart was used for trials at the Dahlgren firing range and never made its way onto the battleship.

The seaplane equipment (hangar, catapults, and crane) had been removed in Dakar. The space thus spared on the stern was used to mount 40 mm anti-aircraft guns on the rear deck. The overall anti-aircraft armament was massively reinforced, with 48 20 mm AA guns in single mounts replacing the original 13.2 mm Hotchkiss machine guns, and 14 quad 40 mm turrets replacing the original 37 mm semi-automatic guns. Adoption of US-pattern secondary batteries made providing ammunition easier; a special factory had to be set up to produce ammunition for the main battery. She remained with only two rangefinders on the fore tower, and the rear mast was shortened. She was fitted with air and surface warning radar, but the U.S. Navy was reluctant to provide gunnery practice radars. All these modifications increased her displacement by 3000 t. After sea trials – with a maximum speed of 30.2 kn – the refit was declared complete on 10 October 1943.

The Richelieu sailed for Mers el-Kebir on 14 October and thence to Scapa Flow, arriving on 20 November. She served with the British Home Fleet from November 1943 to March 1944, participating in an operation off the Norwegian coast in January 1944. She was then transferred to the British Eastern Fleet to cover for British battleships undergoing refit; this was despite reportedly strong anti-Gaullist sympathies on board and limitations of her radar and ammunition (only available from US sources). She arrived at Trincomalee, Ceylon (now Sri Lanka) on 10 April 1944, in time to join the attack by Task Force 65 on Sabang on 19 April (Operation Cockpit) and on Surabaya in May 1944 (Operation Transom); she also served in Operations Councillor and Pedal, in June. On 22 July, she sailed to attack Sabang and Sumatra (Operation Crimson) and returned to Trincomalee on 27 July.

Relieved by HMS Howe (32), the Richelieu returned to Europe. After about a week in Toulon, she sailed for Casablanca, where she arrived on 10 October 1944, for careening. She was refitted in Gibraltar in January 1945, and rejoined the Eastern Fleet till the end of the war against Japan, arriving back at Trincomalee on 20 March 1945. Now with Task Force 63 of the British East Indies Fleet, she joined in more bombardments of Sabang in April and of the Nicobar Islands in late April to early May. The next operation, to intercept the JAPANESE CRUISER Haguro, was abortive.

The Richelieu refitted at Durban from 18 July to 10 August, and arrived via Diego Suarez at Trincomalee on 18 August, learning of the Japanese surrender on 15 August. She left Trincomalee on 5 September to participate in the liberation of Singapore, Operation Tiderace. While she was passing down the Straits of Malacca on 9 September, at 07:44 a magnetic mine detonated 17 m to starboard. She eventually limped into Singapore at noon on 11 September.

Post war
After V-J Day, during the last three months of 1945, Richelieu took part in the return of French forces to Indochina, particularly at Nha Trang, with her Fusiliers Marins landing party, and delivering gun support. When Richelieu left for France, the crew received congratulations from General Leclerc, the French Commanding General in Indochina. On 29 December, she sailed for France, and arrived in Toulon on 11 February 1946.

After 1946, she had the classic existence of a warship during peacetime, alternating between training times and such tasks as, maneuvering with the aircraft carrier FRENCH AIRCRAFT CARRIER Arromanches – formerly HMS Colossus (R15) – when she joined the French Navy, taking the President of the French Republic for a visit to the French West Africa colonies in 1947 or officially visiting Portugal. During a careening in Toulon in 1951, she was fitted with French-built radar devices, and received one new-built 380 mm gun and three guns seized by the Germans, two having been installed during the war in shore batteries in Norway and in Normandy, the third having been used for trials at the Krupp proving grounds in Meppen (Germany).

Once in her career (on 30 January 1956), she maneuvered with the Jean Bart for a few hours, before being based in Brest as a gunnery training school. Placed in the reserve fleet in 1958, she was in 1968 decommissioned and sold to Italian ship scrappers.

From Saint-Nazaire to Casablanca
The Jean Bart was laid down in December 1936; it was built in the large Caquot dock in Penhoët later named the "Jean Bart dock" and was expected to leave it in October 1940. In May 1940, it was decided that the uncompleted battleship had to be sent to a safer place in Britain or in French Africa, beyond the Luftwaffe's range. The ship was afloat in the fitting-out basin; however, this was separated from the navigational channel by an earth dam. When it appeared that the Battle of France was on its way to be won by the Wehrmacht by late May, work on dredging the earth dam was begun in order to be ready to leave at a high tide on June 20. Half the propulsion machinery (boilers and turbines) was fitted to be worked when necessary. On June 18, as the German Panzer divisions were approaching, the Commanding Officer was ordered to be ready to leave immediately for Casablanca or to scuttle the ship. It was not before the middle of the next night that the dredging work was finished with very narrow margins for the battleship to pass through, and in the early hours of 19 June, nearly in view of the German vanguard, the Jean Bart – barely 75% completed, her steam engines never having been worked before, and under the threat of German bombers – was taken out of her St. Nazaire's dock by four tugs and reached under her own steam Casablanca, Morocco, on June 22; the average speed on the journey's final leg was 22 kn.

Only one of her two 380 mm main turrets had been installed by then; the second turret's guns had to be left or were lost with the sinking of the vessel shipping them. Her 152 mm secondary battery was also not yet installed, and it was replaced by anti-aircraft machine guns. No rangefinder was fitted. The Jean Bart, moored in Casablanca harbor, stayed uncompleted as facilities to complete her were completely lacking.

On 8 November 1942, Allied landings in French North Africa (Operation Torch) begun. The Jean Bart, with her 380 mm guns opened fire on the U.S. warships covering the landings, range finding being done using the shore stations of Sidi Abderhamane and Dar Bou Azza and the data sent by phone to the battleship. But she was quickly silenced by the second hit from the 406 mm guns of the USS Massachusetts (BB-59), which jammed the turret rotating mechanism on the French battleship. The sixth of the seven 406 mm shells which hit her exploded in a magazine of 152 mm turret, which was empty as these turrets had not been installed. In normal war circumstances, this event would have had catastrophic consequences. These magazines' armor weakness was known, and was intended to be corrected on the Gascogne. On November 10, her 380 mm turret having been overhauled, Jean Bart almost hit the USS Augusta (CA-31), the Task Force 34 flagship. Bombers from the aircraft carrier USS Ranger (CV-4) soon inflicted severe damage on her, two heavy bombs hitting the bow and the stern, and the battleship settled into the harbor mud with decks awash.

Completion
After the French North Africa forces joined the Allies, Jean Bart was made seaworthy to be refitted with American help, as with the Richelieu. The French Admiralty's wish – presented by Vice Admiral Fenard, Chief of the French Naval Mission – to complete the Jean Bart in U.S. shipyards was discussed during 1943. But the U.S. Navy authorities concluded the task exceeded their capacities, for the ship was too different from the equivalent U.S. warships, and the correct parts were lacking. Instead of completing her as designed, it was proposed in May 1943 to complete her with only one main artillery turret, using 340 mm guns taken on the French battleship FRENCH BATTLESHIP Lorraine that had joined the Allied forces (after she had stayed from 1940 to 1943 in Alexandria). Fifteen U.S.-built dual-purpose 127 mm double turrets, sixteen Bofors 40 mm quad mountings, numerous Oerlikon 20 mm mountings, and aircraft installations for six planes (Grumman Avenger or Fairey Barracuda bombers and Hellcat or Seafire fighters), would have transformed the Jean Bart into a kind of hybrid battleship-aircraft carrier. A second proposal, less expensive but always with the same main artillery turret, had seventeen 127 mm double turrets and twenty Bofors quad 40 mm mountings and would have yielded a kind of AA battleship. Admiral King, Commander in Chief, United States Fleet and Chief of Naval Operations, decided finally in March 1944 not to agree to any French proposals, and the Jean Bart stayed in Casablanca.

The question of the Jean Bart's completion was once more discussed by the French Admiralty in 1945. Was she to be scrapped? Completed as a classic battleship as designed? Transformed into an aircraft carrier? On 21 September 1945, the Higher Council of the French Navy agreed rapidly she was not to be scrapped. The discussion to choose between the other possibilities seems to have been rather unsatisfying. Mr. Louis Kahn, Chief Naval Constructor, French Navy, who had designed the in the late 1930s, presented a project for a transformation into an aircraft carrier operating forty/fifty-four planes, for a cost of 5 billion Francs, and with a delay of five years or less. Some admirals, namely Admiral Fenard, formerly chief of the French Naval Mission to the U.S.A., and Admiral Nomy, who had been a Naval Aviation pilot and would be later Chef d'Etat-major Général de la Marine (1951–1953), found surprising that so few planes were being accommodated on a ship with a displacement of 40000 t, as equivalent ships in other navies were operating twice as many planes. In the minutes of the 21 September 1945 meeting of the Navy Higher Council, Rear Admiral Barjot wrote: "The design of aircraft carrier presented to the Council is called, by a member, "caricature" in regard to a project which would be established with the wish to create an efficient aircraft carrier...Despite the war learnings, the outdated myth of big gun goes on dominating our naval doctrine...It was surprising enough to see in 1945 the Navy General Staff supporting, doctrinally, against the aircraft carrier solution, the battleship solution".

It is known that the British aircraft carrier HMS Eagle (R05), laid down in 1942 and launched in 1946, with a displacement of 38600 LT (46000 LT full load), was by then designed for accommodating 80 planes. However, the French experience of a battleship converted into an aircraft carrier, the FRENCH AIRCRAFT CARRIER Béarn, was rather unsuccessful, her slow speed having led to use her only as aircraft transport ship.

It was decided finally to complete Jean Bart as an integral battleship, with the aim to get, with a delay of five years, a command ship, heavily anti-aircraft armed, with a capacity of naval bombing for attack against land. The Jean Bart left Casablanca in August 1945 to Cherbourg, where was, by then, the only usable French graving dock on the French Atlantic coast, and entered in one of the Brest Laninon docks in March 1946. Work progressed slowly as the Brest Navy Yards had to be rebuilt in the meantime after severe wartime destruction. The battleship emerged with a much more compact fore control tower, topped by only one rangefinder (Richelieu had two ones after her refit). In 1948, she received an additional bulge to limit the increase of her draught, due to the planned fitting of a stronger anti-aircraft artillery; her beam reached 35.5 m. Gunnery and speed sea trials showed a top speed of more than 32 kn.

Career
The Jean Bart was officially commissioned on 16 January 1949, but the anti-aircraft short range artillery, twelve 100 mm dual mountings and fourteen Bofors licensed 57 mm dual mountings, was not fitted before 1952–1953.

The Jean Bart was admitted to active service on 1 May 1955. She soon took the President of the French Republic in an official visit to Copenhagen, and went on to Oslo. In July, she took part (in New York) in ceremonies celebrating the 175th anniversary of the Newport landing of French troops led by the Comte de Rochambeau, during the American War of Independence. On 21 October, in Toulon, the Jean Bart succeeded the Richelieu as the flagship of the South Group of Schools.

During her active career, the Jean Bart had a complement of 750 to 900 men; 1500 had been planned. She reached more than 1200 men when she was about to be sent due to the Suez Canal crisis, but even then, only one 380 mm turret and the axial 152 mm turret could be manned.

In 1956, she took part in the operations off Port-Saïd during the Suez Crisis, but the French bombing support of land operations was not primarily by the four shots fired by her 380 mm guns against the land, but by the French Aeronavale Corsairs, and the Jean Bart's main operational contribution was to ship the 1st Foreign Parachute Regiment from Algiers to Cyprus.

After having fired the last French Navy 380 mm gun shots in July 1957, the Jean Bart was placed in reserve, on August 1, 1957, and served as a school ship for the gunnery training schools in Toulon. Afterwards, there were some proposals in 1957–1958 to modernize her anti-aircraft artillery with new 100 mm turrets (Model 53 in place of Model 45), or later to transform her into a guided missile battleship as had been USS Mississippi (BB-41) (but no French-built missile existed at that time, so it was proposed to use the U.S. Terrier missile). In 1964, when a command ship was looked for by the Pacific Center for Nuclear Experiments, the cruiser FRENCH CRUISER De Grasse was preferred to the Jean Bart'', which would have been more expensive to transform.

Decommissioned in 1968, the Jean Bart was scrapped in 1970 near Toulon, leaving the Turkish TCG Yavûz, formerly the SMS Goeben, the only survivor afloat in European waters of the battleship era.

The Jean Bart was overall an experimental battleship, never fully operational, mainly because of budget cuts but also because, when the Jean Bart was completed, the battleship was no longer the capital ship for the French Navy, since instead three aircraft carriers – the FRENCH AIRCRAFT CARRIER Arromanches, FRENCH AIRCRAFT CARRIER La Fayette, and FRENCH AIRCRAFT CARRIER Bois Belleau – operated during the 1950s in bombing support against land in Indochina, in Algeria, and during the Suez Crisis. However, she was very useful post-war as a testbed for new French-built naval AA guns and radars.

Clemenceau and Gascogne
The third unit, the Clemenceau, was laid down in the Salou graving dock as soon as the Richelieu had left it. Work progressed slowly, as the Clemenceau did not have priority in naval building unlike the first pair of the Richelieu class. Thus, in mid-1940 – nearly eighteen months later – she was only 10% completed as a hull section of 130 m. Taken by the Germans as a war booty, she was registered by the Kriegsmarine as Battleship R but the Germans never seriously considered continuation of construction work. Made buoyant, presumably in 1941, to vacate the building basin, moored near the submarine base, or towed to Landevenec, and intended for use by the Germans as a blocking ship to seal off the harbour entrance, this uncompleted hull was sunk during a U.S. air raid at the beginning of the offensive to free Brest (on 27 August 1944) and scrapped post-war. In the late 1950s, the name of Clemenceau was given to the first modern post-war French-built aircraft carrier, FRENCH AIRCRAFT CARRIER Clemenceau.

The fourth unit, the planned Gascogne, was intended to be laid down in the "Jean Bart dock" at Saint-Nazaire as soon as the Jean Bart would have freed the building dock to be transferred in the nearby fitting-out dock, which was done on 6 March 1940. But, when the ship building yard was occupied by the Germans, in June 1940, the battleship had not been yet formally ordered. No work was ever begun, as the keel was not laid down due to the German occupation. Just some stored parts and material would have been declared war booty and registered as Battleship S.