Poster submarine Type XXI

Type XXI, or "Elektroboot", was a revolutionary submarine for its time.

It was fast enough to outrun frigates and corvettes escorting convoys and could travel more than 220 nautical miles underwater at its economical speed (4 to 5 knots). Its diesel engines propelled it to more than 15.6 knots on the surface and 17.5 knots diving on its electric motors. It was therefore faster in the dive than on the surface.

The number of electric batteries three times greater than those of the Type VII-C U-boats. He could thus navigate by diving for two or three days at 5 knots while only using his snorkel for 5 hours.

Her anti-ship and anti-submarine armament was 6 torpedo tubes of 533 mm forward. It carried 23 acoustic torpedoes: 6 in the tubes and 17 spare. On the massif, two double pseudo-turrets with a caliber of 20 or 30 mm ensured its anti-aircraft defense.

The Type XXI was equipped with a very sensitive passive sonar for the time, housed at the base of the bow. It also carried a radar detector and a surface surveillance radar as well as two periscopes; one for attack (more discreet) and another for standby (more precise).

 A program provided for the priority construction of 1,500 units (U-2500 to U-4000) at the rate of three per week. But his late arrival at the end of the war, little helped by a complex adjustment, could not change the outcome of the war.

However, it was very widely copied and taken up by different countries, and foreshadowed the modern submarine at the start of the Cold War, before the arrival of nuclear propulsion.