WSK Nr 4 PZL Okęcie PZL-101 Gawron. 1958 - History
145b Section 1958-05-14
WSK Nr 4 PZL Okęcie PZL-101 Gawron
On the basis of the Jak-12 M aircraft, it was decided to build an agricultural aircraft. The case was difficult, because the Jak-12 had a lifting capacity of only 350 kg, with a maximum volume of 470 liters. The constructors realized that this solution was provisional and it would be necessary to build a typical agricultural plane. However, at the moment, the team under the supervision of M.Sc. Stanisław Lassota in 1956 has started working on the agricultural version. In 1957, the documentation was ready.
The designers primarily tried to reduce the curb weight of the aircraft. The plane was deprived of a radiocompass, radio station, adjustable engine cover, the right door was removed. The right seat was replaced with a light seat. As for the radio, it was reinstalled during its operation. The performed static tests showed that it was possible to increase the total weight max from 1,450 kg to 1,600 kg. On the back, behind the wings, a distinct hump has been added, which has increased room for a chemical tank. On the top of the hump there is a hatch for pouring chemicals. The capacity of the tank was 800 liters and the lifting capacity was 500 kg. The tank was intended only for loose chemicals. It was filled manually with the use of buckets. A makeshift (wooden) pier was erected, on which the worker with the bucket would climb onto the plane's back and pour chemicals into the tank. At the bottom of the tank there is a dosing device, which is powered by an additional propeller located on the back of the hull. Chemicals fall out in small portions. The quality of dusting depends on the direction and strength of the wind.
Written by Karol Placha Hetman