SM U-77

SM U-77 was one of 329 submarines serving in the Imperial German Navy in World War I, engaged in commerce warfare during the First Battle of the Atlantic.

Design
Type UE I submarines were preceded by the longer Type U 66 submarines. U-77 had a displacement of 755 t when at the surface and 832 t while submerged. She had a total length of 56.80 m, a pressure hull length of 46.66 m, a beam of 5.90 m, a height of 8.25 m, and a draught of 4.86 m. The submarine was powered by two 900 PS engines for use while surfaced, and two 900 PS engines for use while submerged. She had two propeller shafts. She was capable of operating at depths of up to 50 m.

The submarine had a maximum surface speed of 9.9 kn and a maximum submerged speed of 7.9 kn. When submerged, she could operate for 83 nmi at 4 kn; when surfaced, she could travel 7880 nmi at 7 kn. U-77 was fitted with two 50 cm torpedo tubes (one at the port bow and one starboard stern), four torpedoes, and one 8.8 cm deck gun. She had a complement of thirty-two (twenty-eight crew members and four officers).

Operations
U-77 was commanded by Kaptlt Erich Günzel, who was lost with her. She came off the stocks at Hamburg (Vulcan) in 1916; in May and June was at Kiel School, and first entered North Sea with U-76 on 29 June, to join the 1st Half Flotilla.
 * 5 July 1916. Left for the north, and laid mines between about 57.75°N, -2.2°W and 57.78333°N, -2.38333°W. It seems possible she sank in 57.58333°N, -1.45°W before midnight 7 July 1916 as a result of some accident. Before this she had laid mines off Kinnaird Head.

Previously recorded fate
U-77 was thought to have sunk off Dunbar, Scotland in May 1916 as a result of a mine handling accident. The submarine involved was actually U-74.