G7e torpedo

The G7e torpedo was the standard electric torpedo used by the German Kriegsmarine submarines in World War II. It came in 20 different versions, with the initial model G7e(TII) in service at the outbreak of the war. Due to several problems, leading to the German "Torpedokrise" which lasted until the end of 1941, the improved G7e(TIII) took over as the standard electric torpedo used by German U-boats for the rest of the war. G7e torpedoes measured 533.4 mm (21.00 in) in diameter and about 7.2 m (24 ft) in length. Depending on the type, the warhead contained a main charge of 250–280 kg (550–620 lb) of Schießwolle 36, a mixture of dipicrylamine and TNT. All were powered by 60–72 kW (80–100 hp) electric motors and lead-acid batteries which required onboard maintenance to maintain their functionality.
Other major G7e-versions that saw operational service during the war, were the first acoustic homing torpedo G7es(TIV) Falke and its improved successor G7es(TV) Zaunkönig.