Gustav Lönnberg got his flight education in England before the war. After finished education he returned to Sweden and worked for a couple of years as a pilot on target-tugs at Bromma Airport.

In 1941 he returned to England and became a test pilot at RAF’s workshops in northern England. He was later station in a fighting unit.

Lönnberg was shot down on 30 May 1942 over Sicily when he flew a Wellington bomber (‘Q’) equipped with torpedoes.
He became a prisoner of war (P.O.W) but managed to escape and return to England.

From the autumn of 1943 to February 1946 he served in Transport Command flying Liberators, Skymasters and Avro Yorks between England and China.

During the war he flew almost 5000 hours on 119 different types (around 70 of them as a test pilot).

Sources:
Gustaf Lönnberg - Folke Vernersson, Akfeo Förlag 2015, ISBN 978-91-980588-7-1
Torpedflyget anfaller - Gustav H. Lönnberg, 1946 Flyg nummer 8 1946