Leif Dietrichson
Naval officer and polar aviator
- Born
- 1 September 1890, Hønefoss
- Died
- 18 June 1928, forsvant over Barentshavet
- Branch
- The Erasmus branch

Leif Ragnar Dietrichson was born in Hønefoss on 1 September 1890. His father was the physician Kristian Adolph Gustav Emil Dietrichson, who died in 1896 when Leif was six. His mother, Birgitte Lynum, was a music teacher. He was the second youngest of five siblings. Major General Oluf Dietrichson was his paternal uncle, and he belongs to the branch descending from Erasmus Dietrichson.
Dietrichson attended the Naval Academy from 1908 to 1911 and became a torpedo officer. When the Navy’s air service was established in 1915 he transferred to it, and he qualified as a pilot in 1916. From 1918 he commanded the Navy’s flying boat station in Kristiansand. In 1920 he married Gunvor Jebsen. Their son Gustav was born in 1921 and fell in 1945 as a navigator in the Royal Air Force.
In 1923 he met Roald Amundsen and was granted leave to fly on his polar expeditions. In May 1925 two Dornier Wal flying boats took off from Ny-Ålesund toward the North Pole. After about eight hours both had to land on the ice at 87 degrees north, and one of the flying boats was abandoned. Dietrichson and Oskar Omdal fell into a lead on the way across the ice and were rescued by Lincoln Ellsworth. The six men spent three weeks making a runway, and on 15 June they all got into the air together in the other flying boat and made it back to Svalbard. In 1926 Dietrichson declined to join the flight of the airship «Norge».
In 1928 Amundsen asked him to join the search for Umberto Nobile and the airship «Italia». The French flying boat Latham 47 took off from Tromsø on 18 June. About three hours later the last radio message came from the area near Bjørnøya. Six people were on board: Amundsen, Dietrichson and four Frenchmen. None of them was found. A float from the flying boat was found off Troms in the late summer of 1928. Dietrichson was a captain by then. According to Wikipedia a memorial stone stands in his honor in Søndre park in Hønefoss.