The aircraft was designed in response to a Polish Air Force requirement for a modern piston-engined trainer with a retractable
tricycle landing gear to replace
Junak 3 and
Yak-11 aircraft. The main designer was
Tadeusz Sołtyk – hence the designation letters TS. The plane was named
Bies – a folk name for the
devil. Work started in
1953 and the first prototype was flown on July 23, 1955. In
1956 and
1957 it beat three international records in its class. The second prototype was shown at the
Paris Air Show in 1957. In
1957 the first experimental series of 10 aircraft was produced by
WSK-Okecie (designated as
TS-8 BI). A slightly improved main variant, designated as the
TS-8 BII, was produced from 1958 to 1960 by
WSK Mielec. The last 10 machines,
TS-8 BIII, were built with better avionics, in total 251 TS-8 were produced of which 229 were the TS-8 BII variant. The TS-8 had good handling and performance; a noisy engine being one of its few flaws. It was the first really modern aircraft designed in Poland after the war, that also used a Polish engine. ==Design==