A two-seat training aircraft designed by Tadeusz Soltyk, intended primarily for military pilot training. It was the first all-metal aircraft designed in Poland after World War II. It had very good handling characteristics.
In 1957, the first series of 10 examples was produced, armed with a machine gun and two bomb racks. A year later, this variant was replaced in production by the BII variant, in which the armament was replaced with a gun camera. Between 1957 and 1960, 229 examples were produced. In 1966, the first Bies aircraft withdrawn from military aviation were transferred to aero clubs, where they were used until 1978. In military aviation, the Bies was used until 1975.
Two examples, adapted for tropical climate, were purchased by Indonesia. The Bies set three records in its class — altitude of 7,084 m, distance of 2,884 km in a closed circuit, and speed of 320 km/h in a closed circuit.
The exhibited example is the first prototype bearing the registration SP-GLF, first flown by Ludwik Natkaniec on 23 July 1965.
| Wingspan | 10.5 m |
| Length | 8.6 m |
| Takeoff weight | 1550 kg |
| Maximum speed | 310 km/h |
| Ceiling | 6000 m |
| Range | 750 km |
| Armament | – |
| Engine | radial PZL WN-31, 330 hp (242 kW) |
