The rapid expansion of US training facilities in 1941 created a sudden need for trainer aircraft at a time when it seemed likely that raw materials, notably aluminium and magnesium alloys, would have to be conserved for first-line types. An engineering team led by Beech's T.A. Wells evolved the Beech Model 26, which was the first all-wood trainer to be accepted by the US Army Air Force. This was given the designation AT-10 Wichita. The design avoided, where possible, the use of compound curves and of hot moulding processes for the structure's sub-assemblies, allowing them to be sub-contracted to non-specialist wood-working firms: 85 per cent of the airframe was manufactured on this basis, with final assembly by Beech.

Metal airframe parts were limited to engine nacelles and cowlings, and panelling around the cockpit section. Perhaps the most interesting innovation was the use of wooden fuel tanks lined with synthetic rubber. For operation as a multi-engined conversion trainer, the Wichita was equipped with dual controls and an autopilot, and entry to the cockpit was via rearward-sliding side windows. The AT-10 was powered by two 220kW Lycoming R-680-9 engines, and by 1943 Beech had completed four contracts, for 150, 191, 18,080 and 350 aircraft respectively, bringing the total built at Wichita to 1,771. The last of these was delivered on 15 September 1943. Beech then supplied engineering and production data to the Globe Aircraft Corporation of Dallas, Texas, so that a further 600 could be manufactured.