With the end of World War II, the Aleksandr Yakovlev Design Bureau began work on developing a new transitional trainer aircraft. This two-seat airframe was intended for training pilots who had completed initial instruction on the Po-2. The new aircraft was to have performance close to that of fighters, while at the same time being simple and inexpensive to produce. The design was based on technical solutions applied in the Yak-3U fighter.
The prototype was built in 1946. The new training airframe had an all-metal construction in a low-wing configuration. It was powered by an ASh-21 engine rated at 700 hp. The equipment enabled training in instrument flying, aerial reconnaissance, and air combat. The aircraft entered serial production in 1947, and the first examples reached regiments that same year. Soon, Yak-11 aircraft were also introduced into the equipment of the Voluntary Society for Cooperation with the Army, Aviation and Navy (DOSAAF). By then, the type served as a transitional trainer from Yak-18 aircraft to fighters.
Yak-11 aircraft, despite their advantages, were difficult to fly. During takeoffs and landings in particular, the machines had a tendency to veer off course. A total of over 4,500 airframes were produced in the USSR and Czechoslovakia (as Let C-11), including some with a nosewheel undercarriage (Yak-11U). They were used by air forces of many countries, including Albania, Afghanistan, Iraq, Austria, and Yemen. In the Polish military aviation, Yak-11s were operated from 1950 to 1962. The first public presentation took place during the Aviation Day in 1951, and the Yak-11s remained in service until the introduction of the Polish TS-8 Bies aircraft.
The exhibited specimen was produced in the USSR with factory number 64236. The aircraft was used by the Polish military aviation until 1962. In 1964, after the Aviation Exhibition marking the 20th anniversary of the People’s Republic of Poland, it was transferred to the Museum’s collection.
| Wingspan | 9,4 m |
| Length | 8,5 m |
| Takeoff weight | 2440 kg |
| Maximum speed | 460 km/h |
| Ceiling | 8000 m |
| Range | 1250 km |
| Armament | 1 heavy machine gun cal. 12.7 mm, 2 bombs of 50 kg each |
| Engine | 7-cylinder radial Shvetsov ASh-21 rated at 515 kW (700 hp) |
