The serial numbers shown below have been derived from official sources. Regardless of the service branch that a particular airplane was delivered to or operated by, all L-5’s were originally requisitioned for the U.S. Army Air Forces and each was assigned a seven digit USAAF serial number. All of the L-5’s delivered to the Navy, Marine Corps, British Royal Air Force and other entities were reassigned from these ranks. Every L-5 was originally issued a steel USAAF data plate that was stamped with its serial number and riveted to the cockpit side of the right hand “match rib” . Many of these identification plates did not include the date of manufacture or acceptance, so that information can only be derived from the individual aircraft record card. Most did bear the government contract number.
The first two digits of the USAAF serial numbers, separated by a hyphen (42-, 44- and 45-), indicate the fiscal year in which the money for their purchase was appropriated Congress. It is NOT necessarily the year of manufacture or delivery and, as mentioned above, one has to refer to the aircraft record card for that information. All but the first ten 42-series aircraft were delivered during 1943 and 1944. All of the 44-series airplanes prior to serial number 44-17216 were delivered during 1944 and the rest were built in 1945. All of the 45-series airplanes were delivered in 1945 except for those cancelled when the war ended. About 45 undelivered planes were completed in 1946 and sold on the civilian market. While most have USAAF data plates they never saw military service.
When the serial numbers were painted on the aircraft, the first number of the 2-digit year was omitted, as was the hyphen. For example, L-5E-1 serial number 44-17570 was painted on the fin as 417570.
A note about the RAF serial numbers. Only KJ445 and up are verified match-ups as indicated on the USAAF record cards. The rest are based on the assumption that the numbers were assigned sequentially as the aircraft arrived in India. Since the third group arrived before the second group it is assumed the numbers KJ388 through KJ397 were applied to them and KJ 398 through KJ407 were applied to the second group. .