|Kungliga Jämtlands Flygflottilj|
|Garrison/HQ||Frösön, Östersund Municipality|
Gösta von Porat (1926-1934)
|Bomber||B 4, B 5,|
|Fighter||J 26, J 28B, J 29F, J 32B, J 35D, JA 37, JAS 39|
|Utility helicopter||Hkp 2, Hkp 3, HKP 10|
|Reconnaissance||S 1, S 6, S 14, B 17A,|
|Trainer||G 101, Se 102, Se 103, Se 104, Sk 11, Sk 12, Sk 15, Sk 16, Sk 50|
|Transport||Tp 2, Tp 4, Tp 5, Tp 78, Tp 83|
F 4 Frösön, Kungliga Jämtlands Flygflottilj, Royal Jämtland Air Force Wing, or simply "F 4", is a former Swedish Air Force wing with the main base located at Åre Östersund Airport outside Östersund on Frösön in the middle of Sweden.
The airbase was set up in 1926 as the 4th Flying Corps at the old base of Jämtland Field Ranger Regiment at Frösö läger (Frösö camp). The main task was to perform reconnaissance for army units.
In 1930, the duties were extended to bombing with B 4 and later B 5 planes.
In 1936 the Flying Corps was reorganized as an own branch (the Air Force) and the unit was renamed Jämtlands Flygflottilj (Jämtland Air Force Wing).
In 1947, the wing was yet again redesigned as a fighter wing and received surplus P-51 Mustangs designated as J 26. These were only kept for five years until they were replaced by J 28A jets in 1952. Again, after only four years, they were in turn replaced by J 29A in 1956.
Swedish Prime Minister Stefan Löfven famously served as a Munitions Systems specialist Conscript with the F 4 Wing for the duration of his 1-year compulsory military service in 1976-77.
The JAS 39 Gripen served briefly for only a year as a replacement for the Viggens until the wing was decommissioned in 2005.
Webpage listing all air force squadrons in Sweden (in Swedish)