German Type VIIC submarines were preceded by the shorter
Type VIIB submarines.
U-308 had a displacement of when at the surface and while submerged. She had a total length of , a
pressure hull length of , a
beam of , a height of , and a
draught of . The submarine was powered by two
Germaniawerft F46 four-stroke, six-cylinder
supercharged diesel engines producing a total of for use while surfaced, two
Garbe, Lahmeyer & Co. RP 137/c
double-acting electric motors producing a total of for use while submerged. She had two shafts and two
propellers. The boat was capable of operating at depths of up to . The submarine had a maximum surface speed of and a maximum submerged speed of . When submerged, the boat could operate for at ; when surfaced, she could travel at .
U-308 was fitted with five
torpedo tubes (four fitted at the bow and one at the stern), fourteen
torpedoes, one
SK C/35 naval gun, 220 rounds, and two twin
C/30 anti-aircraft guns. The boat had a
complement of between forty-four and sixty. ==Service history==