L-23 Seminole was the USAF designation for the Beechcraft Twin Bonanzas and Queen Airs in its inventory. The Twin Bonanzas were designated L-23A to L-23E and the Queen Airs as L-23F.

When US military aircraft designations were revised in 1962, the only remaining Twin Bonanzas were L-23Ds, which became U-8Ds, and the L-23F Queen Airs became U-8Fs.

Designation sequence (USAF, pre-1962): L-19 - L-20 - L-21 - L-23 - L-24 - L-25 - L-26

Designation sequence (US military, post-1962): U-5 - U-6 - U-7 - U-8 - U-9 - U-10 - U-11

U.S. military utility aircraft 1950-1959