The Type VIIC was the workhorse of the German U-boat force, with 568 commissioned from 1940 to 1945.
The first VIIC boat commissioned was the U-69 in 1940. The Type VIIC was an effective fighting machine and was seen almost everywhere U-boats operated, although its range of only 6,500 nautical miles was not as great as that of the larger Type IX (11,000 nautical miles), severely limiting the time it could spend in the far reaches of the western and southern Atlantic without refueling from a tender or U-boat tanker. The VIIC came into service toward the end of the first "Happy Time"[Note 6] near the beginning of the war and was still the most numerous type in service when Allied anti-submarine efforts finally defeated the U-boat campaign in late 1943 and 1944.
Type VIIC differed from the VIIB only in the addition of an active sonar and a few minor mechanical improvements, making it 2 feet longer and 8 tons heavier. Speed and range were essentially the same. Many of these boats were fitted with snorkels in 1944 and 1945.
They had the same torpedo tube arrangement as their predecessors, except for U-72, U-78, U-80, U-554, and U-555, which had only two bow tubes, and for U-203, U-331, U-351, U-401, U-431, and U-651, which had no stern tube.
On the surface the boats (except for U-88, U-90 and U-132 to U-136 which used MAN M6V40/46s) were propelled by two supercharged Germaniawerft, 6 cylinder, 4-stroke M6V 40/46 diesels totaling 2,800 to 3,200 hp (2,100 to 2,400 kW) at 470 to 490 rpm.
For submerged propulsion, several different electric motors were used. Early models used the VIIB configuration of two AEG GU 460/8-276 electric motors, totaling 750 hp (560 kW) with a max rpm of 296, while newer boats used two BBC (Brown Boveri & Co) GG UB 720/8, two GL (Garbe Lahmeyer) RP 137/c electric motors or two SSW (Siemens-Schuckert-Werke) GU 343/38-8 electric motors with the same power output as the AEG motors.
Perhaps the most famous VIIC boat was U-96, featured in the movie Das Boot.
Nazi Germany's Type VIIC/41 was a slightly modified version of the VIIC and had the same armament and engines. The difference was a stronger pressure hull giving them a deeper test depth and lighter machinery to compensate for the added steel in the hull, making them slightly lighter than the VIIC. A total of 91 were built; all of them from U-1271 onwards lacked the fittings to handle mines.
Today one Type VIIC/41 still exists: U-995 is on display at Laboe (north of Kiel), the only surviving Type VII in the world.