|Port of registry:|
|Builder:||Helsingborgs Varfs AB|
|Fate:||In active service as of 1946|
|Class and type:||Cargo ship|
|Length:||277 ft 6 in (84.58 m)|
|Beam:||41 ft 4 in (12.60 m)|
|Depth:||16 ft 2 in (4.93 m)|
|Installed power:||Triple expansion steam engine|
Heidberg was a 1,714 GRT cargo ship that was built in 1943 by Helsingborgs Varfs AB, Helsingborg, Sweden. In 1945, she was seized by the Allies at Stettin, passed to the Ministry of War Transport (MoWT) and was renamed Empire Convention. She was allocated to the Soviet Union in 1946 and renamed Ernst Thaelmann.
The ship was 277 feet 6 inches (84.58 m) long, with a beam of 41 feet 4 inches (12.60 m) and had a depth of 16 feet 2 inches (4.93 m).
The ship was propelled by a triple expansion steam engine, which had cylinders of 20 1⁄16 inches (51.0 cm), 29 1⁄2 inches (75 cm) and 52 3⁄5 inches (134 cm) diameter by 35 7⁄16 inches (90.0 cm) stroke. The engine was built by Helsingborgs Varfs.
Heidberg was built for August Bolten Wm Müllers Nachfolger, Hamburg. She was seized in May 1945 at Stettin, passed to the MoWT and renamed Empire Convention. Her port of registry was changed to London. She was placed under the management of Ellerman's Wilson Line Ltd. The Code Letters GMFM and United Kingdom Official Number 180342 were allocated. In February 1946, Empire Douglas was transferred to the Soviet Union under the Potsdam Agreement. She was renamed Ernst Thaelmann and worked in Sakhalin Shipping Company.
- Mitchell, W.H.; Sawyer, L.A. (1995). The Empire Ships. London, New York, Hamburg, Hong Kong: Lloyd's of London Press Ltd. p. not cited. ISBN 1-85044-275-4.
- "LLOYD'S REGISTER, STEAMERS & MOTORSHIPS" (PDF). Plimsoll Ship Data. Retrieved 21 October 2010.
- "Enemy Ships for Russia". The Times (50376). London. 14 February 1946. col C, p. 2.
- МОРФЛОТ » Морской флот СССР. Суда ММФ СССЗ. » Морские Пароходства » Портал: Сахалинское Морское Пароходство