Ships
- HNLMS Jacob van Heemskerck (D20) Captain from 30 April 1943 · Relieved on 27 May 1944
Willem Harmsen had Jacob van Heemskerck from 30 April 1943 until 27 May 1944. Uboat.net lists him as kapitein ter zee, which it glosses as captain. The Dutch history calls him captain and says he had previously commanded Campbeltown and Isaac Sweers. The English rank Captain comes from that gloss and from the Dutch history's own word.
Uboat.net records that he was born on 14 June 1893 at Amersfoort and died on 23 October 1970 at Nijkerk.
The rank table lists luitenant ter zee der 3e klasse, glossed sub-lieutenant, on 31 July 1915; luitenant ter zee der 2e klasse, glossed lieutenant, on 31 July 1917; luitenant ter zee der 1e klasse, glossed lieutenant-commander, on 4 February 1926; kapitein-luitenant ter zee, glossed commander, on 1 April 1938; and kapitein ter zee, glossed captain, on 1 June 1942. He retired on 1 April 1946. The page says it has no career narrative.
He relieved Edzard Jacob van Holthe on 30 April 1943. The Dutch history says his first assignment was to escort Nieuw Amsterdam to Wellington, and that the ship then went back to Australian convoy duty. She left Australia on 14 December 1943 for the Mediterranean, reached Port Said on 6 January 1944, and was kept there as an anti-aircraft escort instead of going on to Britain. On 20 April 1944, with convoy UGS 38, Paul Hamilton exploded. The history says 580 men were killed. Her asdic reported two torpedoes, which missed, and USS Lansdale (DD-462) sank. He left on 27 May 1944, when Willem van den Donker took her. The pages do not add a separate account of Campbeltown or of the loss of Isaac Sweers beyond the Dutch history's clause.
He retired on 1 April 1946. He died at Nijkerk on 23 October 1970.