15 cm sFH 18


The 15 cm schwere Feldhaubitze 18 or sFH 18, nicknamed Immergrün, was the basic German division-level heavy howitzer during the Second World War, serving alongside the smaller but more numerous 10.5 cm leFH 18. Its mobility and firing range and the effectiveness of its 44 kilogram shell made it the most important weapon of all German infantry divisions. A total of 6,756 examples were produced.
It replaced the earlier, First World War-era design of the 15 cm sFH 13, which was judged by the Krupp-Rheinmetall designer team of the sFH 18 as completely inadequate. The sFH 18 was twice as heavy as its predecessor, had a muzzle velocity increase of forty percent, a maximum firing range 4.5 kilometers greater, and a new split-trail gun carriage that increased the firing traverse twelvefold. The secret development from 1926–1930 allowed German industry to deliver a trouble-free design at the beginning of German re-armament in 1933. It was the first artillery weapon equipped with rocket-assisted ammunition to increase range. The sFH 18 was also used in the self-propelled artillery piece schwere Panzerhaubitze 18/1.
The sFH 18 was one of Germany's three main 15 cm calibre weapons, the others being the 15 cm Kanone 18, a corps-level heavy gun, and the 15 cm sIG 33, a short-barreled infantry gun.

Design and development

Development work on the sFH 18 began in 1926 and the gun was ready for production by 1933. The model year was an attempt at camouflage. The gun originated with a contest between Rheinmetall and Krupp, both of whom entered several designs that were all considered unsatisfactory for one reason or another. In the end the army decided the solution was to combine the best features of both designs, using the Rheinmetall gun on a Krupp carriage.
The carriage was a relatively standard split-trail design with box legs. Spades were carried on the sides of the legs that could be mounted onto the ends for added stability. The carriage also saw use on the 10 cm schwere Kanone 18 gun. As the howitzer was designed for horse towing, it used an unsprung axle and hard rubber tires. A two-wheel bogie was introduced to allow it to be towed, but the lack of suspension made it unsuitable for towing at high speed.
The gun was officially introduced into service on 23 May 1935, and by the outbreak of war the Wehrmacht had about 1,353 of these guns in service. Production continued throughout the war, reaching a peak of 2,295 guns in 1944. In 1944, the howitzer cost 40,400 RM, 9 months and 5,500 man-hours to make.

Variants

Several other versions of the basic 15 cm were produced:
YearPre-War1939194019411942194319441945Total
Produced, pcs.1,3531905805166367852,2954016,756

Combat record

The first field combat for the 15 cm sFH 18 was with the Chinese National Revolutionary Army in the Second Sino-Japanese War. The Chinese were desperately short on artillery guns and other heavy weapons, but the few 15 cm sFH 18 units the Chinese did have hopelessly outclassed their Japanese counterparts which were mainly the Type 38 15 cm howitzer and Type 4 15 cm howitzer, forcing the Japanese to introduce the Type 96 15 cm Howitzer. Some earlier pieces of sFH18 in China were designed specially with a 32/L barrel, known as sFH18 32/L; the maximum range was increased to 15 km.
Against the Soviet Union however, the sFH 18 proved to be greatly inferior to the Red Army corps artillery 122 mm gun and 152 mm ML-20 gun-howitzer, whose maximum range of and allowed it to fire counter-battery against the sFH 18 with a and advantage respectively. This led to numerous efforts to introduce new guns with even better performance than the ML-20, while various experiments were also carried out on the sFH 18 to improve its range. These led to the 15 cm sFH 18M version with a removable barrel liner and a muzzle brake that allowed a larger "special 7" or 8 charge to be used. The 18M increased range to, but it was found that the liners suffered increased wear and the recoil system could not handle the increased loads in spite of the brake. This led to a more interesting modification, the introduction of the 15 cm R. Gr. 19 FES ammunition, which used a rocket-assisted round that could reach and give it some level of parity with the A-19 and ML-20.
Several countries continued fielding the sFH 18 after the war in large numbers including Czechoslovakia, Portugal and many South American and Central American countries. Finland bought 48 sFH 18 howitzers from Germany in 1940 and designated them 150 H/40. These guns were modernized in 1988 as the 152 H 88, and they were used by the Finnish Army until 2007.

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