Main Menu

JAI JAI-2 P. P. Postyshev
Two-seater glider "P. P. Postyshev" in Koktebel.
The JAI-2, or JAI P. P. Postyshev (In Russian: П. П. Постышев (ХАИ-2))was created to study tailless design. The name was chosen in honour of the secretary general of the central committee of the Communist Party of Ukraine Pablo Petrovich Postyshev.
On February 6, 1934 at the GVF Aviation Repair Shops in Kharkov (JARM) the first flight of the Osoaviajimoviets JAI tailless glider designed by Bening was developed. This project was followed by a second model in a two-seater configuration, which received the official name P. P. Postyshev (JAI-2). The glider was designed and built at the JAI by Pavel Georgievich Bening.
The two-seater JAI-2 P. P. Postishev was a tailless flying wing configuration. The construction was of wood with plywood coating.
The wing featured in-plane sagging and notable positive dihedral, ending in vertical surfaces that included the aerodynamically compensated rudders. The wing trailing edge incorporated full-span ailerons used to gain control of pitch and roll. The selected wing profile was M-12.
On the centroplane were the open tandem cabs, protected only by a small front windshield. The pilot was in the lead. The passenger was located in the rear cabin with his back to the pilot, a solution that was dictated by the need to achieve the least possible deviation of the aircraft's center of gravity, characteristic for this type of airplane configuration.
A central wooden ski was used as the landing gear, supported by small skids under the vertical planes of the wing tip.
The construction of the glider was carried out at the GVF Aviation Repair Workshops in Kharkov (JARM) in 1934 and lasted a month and a half.
The glider tests took place in September 1934 in Kharkov.
Later in 1934 the model would participate in the X National Sailing Competitions held in Koktebel. The glider was aero-towed using a Polikarpov R-5 piloted by V. A. Keglevich as a tug. The glider had the pilot L. S. Ryzhkov at the controls and the constructor Pavel Bening as a passenger. Once at the destination the glider was improved with the addition of the front windshield and the rear upper fairing.
During the competitions the pilot L. S. Ryzhkov performed on the “P. P. Postyshev” flights over thermals. During the competitions, on October 2, pilot S. N. Anojin made the first experimental jump from the back seat of the glider while flying at 300 meters. Getting out of the back seat Anojin left the cabin and stood on the wing. To achieve the opening of the parachute, the glider began a dive until it reached a speed of 105 km / h. Upon reaching the height of 300 meters, he activated the ring and without jumping into the void, he detached himself from the device when he was dragged by the parachute.
The effectiveness of this test opened the possibilities of preparing paratroopers without the need for free jump in the air before proceeding to open the parachute. As a result, it was also proposed to modify the configuration of the rear cabin of the JAI-2 “P. P. Postyshev”, so that the skydiver, without getting up from the seat and without standing on the wing, could parachute.
The P. P. Postyshev proved to be more effective than the LAK-1, LAK-2, TsAGI-1 and TsAGI-2, also in the tailless configuration, and set a glide record for tailless models by staying in the air for 58 minutes.
According to the magazine “Samoliot” upon return from Koktebel on October 6, three gliders without a tail made a record-breaking flight without stops forming a tow “train” to the city of Kharkov. Towed by a Polikarpov P-5 piloted by the pilot Danilivtsiev, the TsAGI-1, piloted by Skorodumov remained in the center, to his left the “P. P. Postyshev” piloted by L. S. Ryzhkov with technician M. Lass in the back seat and on the right the TsAGI-2 with pilot Yudin. The gliders stayed in the air for 4 hours and 30 minutes, covering a distance of 620 km / h with an average speed of 145 km / h. During part of the flight the "train" was immersed in a cloudy area with turbulence, but the gliders passed this test.
Later the P. P. Postyshev glider (JAI-2) was used by the JAI for towed aerobatic flights. On August 19, 1936 he was successfully shown in the Túshino air parade, performing high figures.
In August 1936 L. S. Ryzhkov began testing an improved version of the JAI-2, but on July 12, 1937 the model was destroyed.
Wingspan: 10.90 m
Wing area: 22 m²
Length: 3.75 m
Height: 1.1 m
Stabilizer surface: 1.17 m²
Area of ​​the empennage: 1.54 m²
Aileron surface: 1.17 m²
Empty weight: 160 kg
Wing loading: 14.6 kg/m²
Accommodation: 2

Copyright © 2021 all-aero. All Rights Reserved.
Joomla! is Free Software released under the GNU General Public License.