Częstochowa 2025-08-09
145b Section 1958-05-14
WSK Nr 4 PZL Okęcie PZL-101 Gawron. Poland
History
It was decided to build an agricultural aircraft based on the Yak-12M. The project was challenging, as the Yak-12 had a payload capacity of only 350 kg, with a maximum volume of 470 liters. The designers realized that this solution was provisional and that a purely agricultural aircraft would have to be built. However, in 1956, a team led by Stanisław Lassota, M.Sc., began work on the agricultural version. In 1957, the documentation was ready.
The designers primarily sought to reduce the aircraft’s empty weight. The aircraft was deprived of its radio compass, radio station, adjustable engine cover, and the right door. The right seat was replaced with a lightweight seat. The radio station was reinstalled during operation. Static tests showed that the maximum gross weight could be increased from 1,450 kg to 1,600 kg. A distinct hump was added to the tail, behind the wings, increasing the space for a chemical tank. A hatch for pouring chemicals was located at the top of the hump. The tank capacity was 800 liters, with a load capacity of 500 kg. The tank was designed only for bulk chemicals. It was filled manually using buckets. A makeshift wooden platform was erected, and a worker with a bucket would climb onto the tail of the aircraft and pour chemicals into the tank. A dosing device was placed in the bottom of the tank, powered by an additional propeller located on the tail of the fuselage. The chemicals were released in small portions. The quality of the dusting depended on the wind direction and strength. A problem arose with the aircraft’s center of gravity shifting. This was solved by giving the wings a 4-degree sweep. This was achieved through triangular inserts between the fuselage and the wing. Large aerodynamic guide vanes (edge plates) were installed at the wing tips. To keep them parallel to the fuselage axis, triangular inserts were also added. The flap deflection was increased to 40 degrees, resulting in a minimum speed of 54 km/h. The main landing gear wheels were also retracted by 0.215 m. This was achieved through a different strut arrangement. The tailplane underwent significant, albeit minor, modifications. The surface area of the control surfaces and trim tabs was increased. The elevator wedge angle was increased. The corrosive effects of chemicals necessitated the use of pushrods instead of cables. During testing, it was found that chemicals were entering the cabin. Therefore, an additional, tight fabric bulkhead was installed.
W wrześniu 1957 roku, przystąpiono do budowy czterech prototypów. Pierwszy egzemplarz otrzymał rejestrację SP-PAG i został oblatany w dniu 14 maja 1958 roku, przez pana Mieczysława Miłosza.
Economically, the PZL-101 Gawron was a major success, partly because it was built using equipment used in the production of the Yak-12, which had long since been depreciated. As a result, the price of the new aircraft was very low, and interest in the PZL-101 Gawron proved unexpectedly high. The first four prototypes were quickly sold abroad: to Spain, Hungary, and Austria (two aircraft). It is extremely rare for aircraft to be sold abroad before they enter service in the manufacturer’s country. The PZL-101 Gawron was a success. The first larger production runs were sold to Hungary and Spain.
325 PZL-101 Gawron aircraft were built. The first 61 aircraft were designated PZL-101, and subsequent ones received the designation PZL-101 A. The PZL-101 A Gawron is a modernized agricultural aircraft. It was produced from 1962. A total of 215 PZL-101A agricultural machines were built.
Due to the lack of a successor and the declining Yak-12M and Yak-12A aircraft, the authorities decided to begin production of a multi-role aircraft based on the PZL-101A. The aircraft was designated PZL-101B. The chemical tank and the fuselage hump were removed. Four seats were installed in the cockpit. Production began in 1965. Most of the 78 aircraft were sent to the Polish People’s Republic Aeroclub. Thirty-two aircraft in the ambulance version were also built based on the PZL-101B. Production of the PZL-101B ended in 1968.
PZL-101 Gawron aircraft, manufactured by PZL Okęcie, were exported to; CCCP (2), Czechoslovakia, Hungary (67), Yugoslavia, Spain, Bulgaria (40), Austria (5), Finland (3), India (6), Turkey (5), Venezuela (1), Vietnam (1).
In the 1970s, the PZL-101 Gawron aircraft were replaced by the PZL-106 Kruk (agricultural) and the PZL-104 Wilga (multi-role). Many agricultural aircraft were stripped of their chemical tanks and, as four-seaters, were transferred to aeroclubs. The PZL-101 Gawron aircraft survived until 2012 and can still be seen today (2025).
The PZL-101A Gawron SP-CHC aircraft.
The PZL-101A Gawron SP-CHC aircraft was converted from agricultural to passenger aircraft. The aircraft’s serial number is 63118 and was built in 1963. After retiring from agricultural service, it was converted to a passenger light aircraft. In August 2015, the aircraft was renovated and given a new livery: a white fuselage with red dots. The wings and main landing gear legs are red. The fuselage bears the FLYSPOT inscription. This livery serves as a flying advertisement. Previously, the aircraft was yellow with red accents. FLYSPOT owns the most modern wind tunnel in Poland, built on the border of Warsaw and Ożarów Mazowiecki. In Częstochowa, the aircraft is used for glider towing and parachute rescue.
Written by Karol Placha Hetman