Born in 1942 and educated as a civil engineer at the Norwegian Institute of Technology (NTH) in Trondheim, Ynnesdal had worked on highway and other projects after graduating in 1965. He served as the section head for drilling at the Norwegian Petroleum Directorate (NPD) from 1974-1977, and helped to supervise planning of Statfjord B.
After spending his final year with the NPD in Bergen, Ynnesdal transferred to Mobil. This followed an occasion when flying from Bergen to Stavanger one Friday in 1978 where he met a number of acquaintances from Mobil. They told him that he had to work in an oil company if he really wanted to see the petroleum industry. There was more action there.
It might have been fun to try Mobil, he had to admit. The company called and offered him a job the following Saturday. After a couple of years getting Statfjord A approved for production, he went offshore as operations manager on that platform.
He moved to Statoil in 1984 and became operations manager for the Gullfaks field in the North Sea.
Interview with Harald Norman Ynnesdal by Trude Meland, Norwegian Petroleum Museum.
Statoil. Gullfaks – glimt fra historien om et helnorsk oljefelt. Stavanger 1990, p 99.
Stavanger Aftenblad , 1 October 1983. “Nordmann i sjefsstolen” .
Norwegian Wire Service (NTB), 21 August 2002. “Harald Ynnesdal er 60 år 10. september”.