Photo from Krigsarkivet's F18 folder via F18 Kamratförening. The photo was probably taken ~1955, prior to the establishment of the military's own helicopter units. Ostermans Aero was very supportive in the military helicopter trials, and it flew roughly 7500 hours for the Armed Forces between 1951-1958). The business came to be 60% of Ostermans' revenue for a period of time (source: "Svenska Civila och Militära Helikoptrar" by Lars E. Lundin).