The United States Air Force, as an independent branch of the U.S. military, was officially established on September 18, 1947, so in 2026 it is 78 years old.

Key facts at a glance

  • Official founding date: September 18, 1947 (National Security Act of 1947).
  • Age in 2026: 78 years.
  • Predecessors: Early Army aviation units beginning in 1907, including the Army Air Corps and later the Army Air Forces in World War II.

Why 1947 matters

The Air Force became a separate service when the National Security Act of 1947 created the Department of the Air Force and split it from the U.S. Army. This recognized that airpower had become central to modern warfare after World War II, where air forces played a decisive strategic role.

“Older than 78?” – A bit of nuance

If you trace the Air Force’s lineage back through its Army roots, you can argue U.S. military aviation is well over a century old, since the Army’s first dedicated aviation section dates to August 1, 1907. But when people ask “how old is the US Air Force,” they almost always mean the independent branch created in 1947, which is why its birthdays are counted from that date.

So: formally 78 years old in 2026, but with aviation heritage stretching back more than 100 years.