Heinz Sieder

Oberleutnant zur See (Crew 38)

1 ship damaged, total tonnage 7,240 GRT
3 ships a total loss, total tonnage 21,550 GRT
1 warship a total loss, total tonnage 1,300 tons

Born  28 Jun 1920 Munich
Died  2 Aug 1944(24)Bay of Biscay

Oblt. z. See Heinz Sieder


1 Oct 1938 Offiziersanwärter
1 Jul 1939 Seekadett
1 Dec 1939 Fähnrich zur See
1 Aug 1940 Oberfähnrich zur See
1 Apr 1941 Leutnant zur See
1 Jan 1943 Oberleutnant zur See


16 Nov 1942 U-boat War Badge 1939
29 Jan 1943 Iron Cross 2nd Class
28 Feb 1944 Iron Cross 1st Class
8 Jul 1944 Knights Cross

U-boat Commands

U-984 17 Jun 1943 2 Aug 1944  (+)  5 patrols (94 days) 

Oblt. z. S.Heinz Sieder on board

Heinz Sieder began his naval career in October 1938. During his officer training he served for seven months on the battleship Scharnhorst and took part in two patrols in the Atlantic.

In April 1941 he joined the U-boat force and after four months of training he became watch officer on a school boat (probably U-46) in the 26th Flotilla.

In January 1942 he became first watch officer on the newly commissioned U-440 and was on board for four patrols. He left U-440 in April 1943 (U-440 was lost a month later) and commissioned the type VIIC U-boat U-984 in June 1943.

In January 1944 he was attached to the 9th Flotilla in Brest (France) and made some patrols in the Channel and in the Atlantic. During a patrol at the end of June 1944 he torpedoed a British destroyer and four US vessels.

Sunk on or about 2 August 1944 in the English Channel south-west of Brighton, in position 50.03.732N, 00.32.398W, by unknown cause (Niestlé, McCartney 2012).


Busch, R. and Röll, H-J. (1999). German U-boat commanders of World War II.
Niestlé, A. (1998). German U-boat losses during World War II.
Rohwer, J. (1998). Axis Submarine Successes of World War Two.

Patrol info for Heinz Sieder

 U-boat Departure Arrival  
1. U-984 30 Dec 1943  Kiel  2 Jan 1944  Egersund   4 days
2. U-984 4 Jan 1944  Egersund  24 Feb 1944  Brest  Patrol 1,52 days
3. U-984 22 May 1944  Brest  27 May 1944  Brest  Patrol 2,6 days
4. U-984 6 Jun 1944  Brest  10 Jun 1944  Brest  Patrol 3,5 days
5. U-984 12 Jun 1944  Brest  19 Jun 1944  St. Peter Port  Patrol 4,8 days
6. U-984 21 Jun 1944  St. Peter Port  5 Jul 1944  Brest  Patrol 4,15 days
7. U-984 26 Jul 1944  Brest  2 Aug 1944  Sunk  Patrol 5,8 days
5 patrols, 94 days at sea

Ships hit by Heinz Sieder

Date U-boat Commander Name of ship Tons Nat. Convoy
25 Jun 1944U-984Heinz Sieder HMS Goodson (K 480) (t.)1,300br
29 Jun 1944U-984Heinz Sieder Edward M. House (d.)7,240amECM-17
29 Jun 1944U-984Heinz Sieder H.G. Blasdel (t.)7,176amECM-17
29 Jun 1944U-984Heinz Sieder John A. Treutlen (t.)7,198amECM-17
29 Jun 1944U-984Heinz Sieder James A. Farrell (t.)7,176amECM-17

4 ships sunk (22,850 tons) and 1 ship damaged (7,240 tons).

We have a picture of this vessel.
(d.) means the ship was damaged.
(t.) means the ship was a total loss (included in ships & tonnage lost).

About ranks and decorations
Ranks shown in italics are our database inserts based on the rank dates of his crew comrades. The officers of each crew would normally have progressed through the lower ranks at the same rate.

Media links

U-Boat Attack Logs

Daniel Morgan and Bruce Taylor

(£ 38.25)

German U-boat Commanders of World War II

Busch, Rainer and Röll, Hans-Joachim

Listing of all U-boat commanders

As an Amazon Associate uboat.net earns a commission from qualifying purchases.