She was built by Blohm & Voss of Hamburg and following just under a year of construction, launched at Hamburg on 2 June 1917. UB-78 was commissioned later that same year under the command of Kptlt. Woldemar Petri. Like all Type UB III submarines, UB-78 carried 10 torpedoes and was armed with a 8.8 cm (3.46 in) deck gun. UB-78 would carry a crew of up to 3 officers and 31 men and had a cruising range of 8,680 nautical miles (16,080 km; 9,990 mi). UB-78 had a displacement of 516 t (508 long tons) while surfaced and 648 t (638 long tons) when submerged. Her engines enabled her to travel at 13.6 knots (25.2 km/h; 15.7 mph) when surfaced and 7.8 knots (14.4 km/h; 9.0 mph) when submerged.[2]
^Helgason, Guðmundur. "WWI U-boat commanders: Woldemar Petri". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 8 March 2015.
^Helgason, Guðmundur. "WWI U-boat commanders: Arthur Stoßberg". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 8 March 2015.
^Helgason, Guðmundur. "Ships hit by UB 78". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 8 March 2015.