What is the oldest aircraft still in service with an airforce today?

Probably the Douglas C-47 (military version of the DC-3 airliner, operated by the Hellenic (Greek) Air Force among others (their C-47's date back to WW2)). Another could be the Antonov An-2, first made from 1947-2002 (in the air forces of Afghanistan and Cuba, and one even in the USAF). A final contender is the Lockheed-Martin U-2, that serves the USAF from 1957 to the present. As for fighter aircraft, the MiG-17 (1953) clone, the Chinese J-7 served in the Pakistani Air Force until 2012, and the MiG-19 (1955) still serves in the North Korean and Zambian Air Forces. As for Western fighters, in would be the McDonald-Douglas F-4, which is in service as of 2008 with the air force's of Egypt, Germany (no longer in service), Greece, Iran (unknown in actually flight worthy), Japan, South Korea, and Turkey.