|Ordered:||5 January 1940|
|Laid down:||1 April 1940|
|Launched:||11 October 1941|
|Commissioned:||20 December 1941|
|Fate:||Sunk after a collision with another U-boat, May 1943|
|Class and type:||Type VIIC submarine|
|Height:||9.60 m (31 ft 6 in)|
|Draught:||4.74 m (15 ft 7 in)|
|Complement:||4 officers, 40–56 enlisted|
She carried out four patrols. She sank no ships.
She was a member of six wolfpacks.
She was sunk after a collision with another U-boat in May 1943.
German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-439 had a displacement of 769 tonnes (757 long tons) when at the surface and 871 tonnes (857 long tons) while submerged. She had a total length of 67.10 m (220 ft 2 in), a pressure hull length of 50.50 m (165 ft 8 in), a beam of 6.20 m (20 ft 4 in), a height of 9.60 m (31 ft 6 in), and a draught of 4.74 m (15 ft 7 in). The submarine was powered by two Germaniawerft F46 four-stroke, six-cylinder supercharged diesel engines producing a total of 2,800 to 3,200 metric horsepower (2,060 to 2,350 kW; 2,760 to 3,160 shp) for use while surfaced, two AEG GU 460/8–27 double-acting electric motors producing a total of 750 metric horsepower (550 kW; 740 shp) for use while submerged. She had two shafts and two 1.23 m (4 ft) propellers. The boat was capable of operating at depths of up to 230 metres (750 ft).
The submarine had a maximum surface speed of 17.7 knots (32.8 km/h; 20.4 mph) and a maximum submerged speed of 7.6 knots (14.1 km/h; 8.7 mph). When submerged, the boat could operate for 80 nautical miles (150 km; 92 mi) at 4 knots (7.4 km/h; 4.6 mph); when surfaced, she could travel 8,500 nautical miles (15,700 km; 9,800 mi) at 10 knots (19 km/h; 12 mph). U-439 was fitted with five 53.3 cm (21 in) torpedo tubes (four fitted at the bow and one at the stern), fourteen torpedoes, one 8.8 cm (3.46 in) SK C/35 naval gun, 220 rounds, and a 2 cm (0.79 in) C/30 anti-aircraft gun. The boat had a complement of between forty-four and sixty.
The submarine was laid down on 1 October 1940 at Schichau-Werke in Danzig (now Gdansk, Poland) as yard number 1490, launched on 11 October 1941 and commissioned on 2 December under the command of Oberleutnant zur See Wolfgang Sporn.
2nd and 3rd patrols
For her second sortie, she barely got out of the Bay of Biscay.
Her third foray took her into the middle of the North Atlantic.
4th patrol and loss
Having left Brest on 27 April 1943, she, along with U-659, were both shadowing a southbound convoy on 5 May in preparation for an attack on the surface when the two U-boats collided. Both boats sank.
U-439 took part in six wolfpacks, namely.
- Panzer (23 November - 11 December 1942)
- Raufbold (11–15 December 1942)
- Neuland (4–6 March 1943)
- Ostmark (6–11 March 1943)
- Stürmer (11–19 March 1943)
- Drossel (29 April - 4 May 1943)
- Busch, Rainer; Röll, Hans-Joachim (1999). German U-boat commanders of World War II : a biographical dictionary. Translated by Brooks, Geoffrey. London, Annapolis, Md: Greenhill Books, Naval Institute Press. ISBN 1-55750-186-6.
- Busch, Rainer; Röll, Hans-Joachim (1999). Deutsche U-Boot-Verluste von September 1939 bis Mai 1945 [German U-boat losses from September 1939 to May 1945]. Der U-Boot-Krieg (in German). IV. Hamburg, Berlin, Bonn: Mittler. ISBN 3-8132-0514-2.
- Edwards, Bernard (1996). Dönitz and the Wolf Packs - The U-boats at War. Cassell Military Classics. p. 189. ISBN 0-304-35203-9.
- Gröner, Erich; Jung, Dieter; Maass, Martin (1991). U-boats and Mine Warfare Vessels. German Warships 1815–1945. 2. Translated by Thomas, Keith; Magowan, Rachel. London: Conway Maritime Press. ISBN 0-85177-593-4.
- Kemp, Paul (1999). U-Boats Destroyed - German Submarine Losses in the World Wars. London: Arms & Armour. ISBN 1-85409-515-3.
- Helgason, Guðmundur. "The Type VIIC boat U-439". German U-boats of WWII - uboat.net. Retrieved 26 December 2014.