Canberra T17 WD 955 (Echo Mike), a Mk B2 built in November 1951 and converted to a Mk T17 in January 1968 was on strength when 360Sqn disbanded in 1994, so had an operational career of approx 43 years, XH135 and XH168 (PR9) had around 47 years.
WH849 (T4) had over 50 Years in service.
How long will the Typhoon last (or have to last)?