[3] The United States Army adopted the Twin Bonanza as the L-23 Seminole utility transport, making it the largest fixed-wing aircraft in its inventory at that time.

According to Ralph Harmon, the airplane's designer, during an initial demonstration flight for the Army, Beechcraft test pilot Claude Palmer crashed while trying to land over a 50-foot (15 m) tree line with the aircraft full of soldiers and sandbags.

The Army was impressed with the structural strength of the Twin Bonanza, eventually purchasing 216 of the 994 examples produced.

[4] It was also the first twin-engined aircraft in its class to be offered to the business market, but the Korean War was raging in the early 1950s and the US Army took almost the entire production for 1952 and 1953.

All three aircraft share the same basic wing design, as well as landing gear, flaps, instrument panels, fuel cells, and more.

[5] "Junior JATO" rocket motors mounted to the tops of the engine nacelles were briefly offered as a factory option for the Twin Bonanza.

[8] The Twin Bonanza has been plagued by a reputation for slow cruise speed, poor fuel economy and high engine overhaul costs relative to other six to eight-seat light piston twins; this has historically kept resale values low, but many owners praise its reliability, good outwards visibility, stable flying qualities and generous interior space, particularly when the three-wide seats are not fully occupied.

The AD affected only Australian aircraft and was not adopted by the airworthiness authority responsible for the type certificate, the US Federal Aviation Administration.

The Beechcraft Twin Bonanza has been involved in the following notable accidents and incidents: Data from Jane's All The World's Aircraft 1956–57[16]General characteristics Performance