Dutch Lieutenant-on-sea of the Royal Dutch Navy.
Johannes or “Jan” was the brother of the Dutch politician and diplomat Gerrit Jan van Heuven Goedhart. Together they joined the Dutch resistance during WW2.
During the German invasion of the Netherlands, part of the Fall Gelb or the German Manstein Plan to invade France, Jan was the captain of the Dutch Torpedo boat Hr.Ms. Z 3(23 March 1920, A’dam – 15 May 1940, Enkhuizen). His task was to prevent the German invasion of the Western heart of Holland (Randstad) via The Ijsselmeer. The Northern road via the Afsluitdijk was closed at the Kazemats of Kornwerderzand during the Battle of the Afsluitdijk.
The German General Kurt Feldt considered to use ships to traverse the Hollandic Water Line via the Ijselmeer, but he was afraid of mines. Actually there were no mines in the Ijsselmeer, so the Torpedo boat of Jan Goedhart was not attacked by one of the 600 Luftwaffe air-planes that were used by the Germans during the Battle of the Netherlands. The according to the Wikipedia “David to Goliath” battle ended soon after the devastating bombing of Rotterdam by the German Luftwaffe and the subsequent terrorist threat by the Germans to bomb other large Dutch cities if the Dutch forces refused to surrender.
On 15 May 1940 the Dutch commander in chief General Winkelman signed the Dutch capitulation (but not for Sealand). That day Jan had to set his ship on fire near the former Zuiderzee sea harbour of Enkhuizen.
Being a Dutch officer, he was taken prisoner of war, but was sent home two months later. Then, he started an underground career in the Dutch resistance.
On 21 March 1942 he wanted to flee to England by boat. The ferryman was Maarten de Graaff (8 December 1874 6h30 PM, Rozenburg – 4 April 1944, Natzweiler). On the ship list were: Max and Bernard Meijers from Amsterdam, Frederick Spitz, Willem Blomme, Cornelis Grashoff, the philosopher Josef Ludvik Fischer (1894-1973), Mikta Baum and Carl Martin Zellermayer. The mission was betrayed by Henk Luyendijk.
The Nazi Judges accused him of the possession of an illegal weapon and crucial military information he wanted to smuggle to England. Jan was executed on 15 August 1942 at the Waalsdorpervlakte.

Link to Dutch Wikipedia