The Gribovski G-14 (Russian: Грибовский Г-14) glider was designed as a two-seater training glider for performing stunts and towed flight. The main objective of its builder when designing this glider was focused on obtaining a simple and cheap model in its production and operation, capable of meeting all the demands of piloting training.

The Gribovski G-14 was designed as a low-wing braced monoplane with wheeled undercarriage. The large wing had a straight leading edge and an inverted trailing edge and was designed with an R-II wing profile. Two parallel struts attached the two-spar wing structure to the top of the fuselage. The wing trailing edge featured large ailerons measuring 1.74 square meters in area.

The landing gear had a conventional composition with two simple 400×150 mm wheels carefully fitted with “pants” and fixed to the wing intrados. The wide span between the two wheels allowed the necessary stability during drag training flights over the ground.

The wide fuselage, covered with plywood, could be used to transport loads and equipment in drag mode, so the structure was reinforced. The cockpits, located in tandem, had a double control system. The Gribovski G-14 was designed for training in night flights, for which it was equipped with the necessary equipment and navigation lights.

The G-14 prototype was built in parallel by two institutions. A first copy was built in the workshops of the Zhukovski Military Aeronautical Academy and another in Factory No.1 “Aviajim”.

The later fate of the G-14 built at the Academy and nicknamed “Komsomol of the VVA” is unknown. The prototype manufactured in the “Aviajim” factory was towed by air in order to participate in the X National Sailing Competitions held in Koktebel in 1934.

The pilots did not value the G-14 positively. The increased weight of the construction and problems in fixing the wing to the fuselage were highlighted as deficient. The positive aspects were the ample capacity of the fuselage, the good structural resistance and the wide span between the main landers.

The positive qualities of the G-14 glider made it an ideal candidate for conducting a series of experiments, so several specimens were built and configured under the purpose of the tests.

The prototype was specially modified at the “Aviajim” Glider Factory in May 1935 to carry out long-distance flight tests based on the refueling of the tug aircraft from the glider itself.

The first fuel transfer test from the glider to the tow plane was carried out on May 24, 1935 while flying at an altitude of 1,200 meters. From the G-14 piloted by Kuzmín 150 kg of fuel were transferred to the Polikarpov R-5 tug piloted by IS Baranov.

On the basis of these tests it was decided to build a specialized variant of the “flying tanker” known as the G-14 TsL-2A. The need to install fuel tanks in the structure increased the flying weight of this version to 780 kg, forcing measures to ensure the necessary structural strength.

The fuel was placed in five aluminum tanks, four in the wing roots (two on each side) and another in the fuselage, located in the position of the rear cockpit, near the center of gravity of the glider. In total the “flying tanker” could carry 500 liters of fuel. A system of pipes and valves ensured the connection of the fuel system with the connecting hook of the tow rope. The cable in this case was in the form of a hose through which the fuel was transferred and in its center was located a cable intended to withstand the drag loads.

In the autumn of 1935 a Polikarpov P-5L piloted by IS Baranov, towing a G-14 TsL-2A glider piloted by KM Vienslav, made a non-stop flight between Moscow and Koktebel, with refuelling in the air. This flight covered a distance of 1524 km, which was also a glider tow record.

As a continuation of the high-altitude trawl experiments, originally tested on the Gribovski G-9, engineer A. Ya. Scherbakov proposed to use a tandem drag method, of which each glider would fly higher than the previous one. To test this system, two more examples of the G-14 were built on the “Aviajim”.

During testing A. Ya. Scherbakov used two gliders, a G-9 and a G-14. As a tug aircraft, a Túpolev TB-1 was used, to which the G-14 was attached and, in turn, the Gribovski G-9.

The Gribovski G-14 was suitably modified for this flight. The forward cabin was closed and covered, opening to the rear. A reel with a 2 mm cable was located in the rear cabin. In order to guarantee the safe extension of this cable, a pipe was fixed to the right side of the fuselage, which ended on the empennage.

Several flights were executed with this chain. At the beginning of April 1936, the results obtained were established: with the Túpolev TB-1 flying at an altitude of 5000 meters, the G-14 had managed to reach 6000 meters and the G-9 7000 meters.

Subsequent flights were cancelled because flights at this point without sealed cabins were quite uncomfortable for the glider pilots.

From a suggestion by A. Ya. Scherbakov fitted one of the G-14s with a sealed cockpit that made it possible to lighten the pilot’s work in the cold, rarefied atmosphere. This cockpit was designed in the form of a kind of stretch calico cocoon preserving the shape of the seated pilot and covered at the top by a metal dome with transparent windows. The instrument panel was located outside the cockpit.

The G-14 thus became the first Soviet fixed-wing aircraft to use a sealed cabin.

Versions:
G-14 – Two-seater training glider from 1934. Two copies built.
G-14 TsL-2A or G-14 “tanker” – Tanker version built and tested in 1935.
G-14 Ts “Tsepochni” – Experimental version built with the aim of testing Scherbakov’s idea of flying a “chain” of towed gliders, each one flying at a higher level than its predecessor. It was tested in flight 1936 – 1937, using a Tupolev TB-1 for towing a G-14 and G-9 .
G-14 GK – 1936 experimental version conceived for high altitude operations with pressurized cabin designed by Scherbakov .
G-14 MP – Single-seater motor glider project from 1936 .
G-14 RP – Single-seater glider project with Dushkin RDA-1-150 reactive power plant .

G-14
Wingspan: 15.00 m
Wing area: 18.00 m²
Length: 7.80 m
Height: 1.35 m
Empty weight: 261 kg
Wing loading: 23.4 kg / m²
Surface of the horizontal planes: 3.0 m²
Empennage surface: 1.38 m²
Spoiler area: 1.74 m²
Glide ratio: 15
Optimal speed: 63 km / h
Minimum descent speed: 1.06 m / s
Accommodation: 2

The Gribovski G-13 (Russian: Грибовский Г-13) was a 1933 lightened version of the successful G-9 competition glider. Gribovski achieved a reduction of 64 kg in relation to the previous glider.

The G-13 glider essentially repeated the G-9. It was a monoplane with a high-wing, braced to the fuselage by struts.

The wing had a double box-shaped internal structure that ran parallel throughout the entire span. At the rear of the wing there was an auxiliary stringer to which the ailerons were attached. The wing composition featured removable rectangular shaped consoles in the central section and elliptical ends. The centroplane was fixed to a central pile of the fuselage structure using screws and was braced by means of a pair of uprights located on each side and fixed to the fuselage structure in the lower section of the gunwales. These uprights were constructed of wood, and they were quite light.

Unlike the G-9, the entire wing was covered with fabric, without the characteristic Gribovski plywood sheets. In this way, a much lighter and simpler wing was achieved. The total weight of the wing was only 45 kg and with the upright structure it reached 51 kg (the relative weight per square meter did not exceed 3.5). This lightness brought about a deficiency: the wing was not very resistant to torsion, which would be solved in the improved version G-13bis, which reinstated the use of plywood covering up to the position of the second spar.

The entire leading edge was covered with 1mm plywood sheets, up to the second spar. The rest of the wing and ailerons were covered with fabric. The wing design used the TsAGI R-II profile proposed by PP Krasilschikov.

The fuselage had a semi-monocoque structure with 12 frames and plywood covering between 1.5 and 2 mm thick. The lower part of the fuselage featured a ski-shaped landing gear. This ski did not belong to the fuselage structure, but was fixed externally and had air suspension using a bicycle tube.

The tail unit featured a medium-sized empennage forming an integral structure with the fuselage. The horizontal planes were linked by a tube-shaped axis that allowed them to rotate together. The leading edge of the empennage and the horizontal planes were also covered with plywood. The rudders were covered with fabric.

The pilot was located in an open cockpit located in front of the wing leading edge, protected by a celluloid windshield. It sat on a board attached directly to the forward frames of the fuselage. The flight control was carried out by means of two pedals and the control stick. The elevator rudders were regulated by an independent tensioner.

The G-13 prototype finished being built in 1933, first flying in the September. In that same year it would participate successfully in the IX edition of the National Gliding Competitions.

In the G-13 glider, the pilot BI Kimmelman made a long-distance flight back to the starting point where he managed to reach 46 km and another open 71 km.

In 1934 the G-13bis version appeared, characterized by an increase in the wingspan and a reinforced structure. The weight of this version grew from 86 to 112 kg. The OSOVIAJIM OSOVIAJIM Glider Factory produced at least two copies of this version, which took part in the X National Gliding Competitions held in Koktebel. Although the G-13 was considered was an excellent glider for primary training, its construction was not continued, since the decision to mass produce the “Upar” glider of OK Antonov had already made.

G-13
Wingspan: 12.1 m
Wing area: 12.8 m²
Length: 5.37 m
Height: 1.42 m
Empty weight: 86 kg
Elevator area: 1.50 m²
Rudder surface area: 0.8
Ailerons area: 1.72
Wing loading: 12.9 kg / m²
Glide ratio: 17
Accommodation: 1

In the fall of 1931 Gribovski began towing experiments with the G-2bis glider, using as a tug a U-1 school biplane (a copy of the Avro 504K built in the USSR).

The experience gained during these flights allowed Gribovski to develop glider versions conceived from the outset to be aero-towed. Up to this time in the USSR the gliders only took off from heights with the help of some elastic tensioners that, when released, generated the necessary force to launch the glider.

The Gribovski G-9 (Russian: Грибовский Г-9) was designed as a single-seater glider with a braced high wing, specially prepared for aero-tow.

The wing, with a double spar, featured removable rectangular consoles in the central section and elliptical ends. This plane was braced by means of a pair of uprights located on each side and fixed to the fuselage structure in the lower section of the gunwales. The entire front of the wing was covered with 1mm plywood sheets, up to the position of the second spar. The rest of the wing and ailerons were covered with fabric. The wing design used the TsAGI R-II profile proposed by PP Krasilschikov.

The tail unit had planes braced also by simple uprights and located directly at the bottom of the empennage. The leading edge of the empennage and horizontal planes also featured plywood overlay. The rudders were covered with fabric.

The fuselage had a semi-monocoque structure with 12 frames and plywood covering between 1.5 and 2 mm thick. At its bottom was a ski-shaped landing gear with air suspension using a bicycle inner tube.
The pilot was located in an open cockpit located in front of the wing leading edge.

Built by Gribovski in 1932, the first of these gliders appeared in the winter of 1931 – 1932.

In parallel with the construction of the G-9 Gribovski began the organization of a long-range towed flight on this glider. To develop this flight Gribovski invited the experienced glider pilot VA Stepanchonok. The flight was planned for the Moscow – Koktebel route in order to arrive in time to participate in the VIII National Sailing Competitions.

On the 29 of September of 1932 the G-9 flown by VA Stepanchonok, towed by a Polikarpov U-2 piloted by Gribovski, it took-off from Tushino airfield for the flight. The arrival in Koktebel was on October 6 at 6:00 p.m. The selected route covered: Moscow – Ryazan – Tambov – Zadonsk – Voronezh – Evdókovo – Kantemirovka – Lugansk – Yeisk – Chernoerkovski – Kerch – Koktebel, covering a total distance of 1700 km in 19 hours of flight. This long-range flight demonstrated the potential of using towed gliders to transport cargo and people.

During the competitions in Koktebel the flight tests were carried out with excellent results. On September 5, during competitions in Koktebel, Stepanchonok set a new record for high school aerobatics flights. During 2 hours and 6 minutes, the G-9 would execute 115 loops, 13 spin turns and inverted flight for 1 minute and 8 seconds.

The first prototype G-9 would be destroyed in an accident the 31 of October of 1932, when piloted by the collaborator of the TsAGI LV Kozlov, collided with another competitor, the SH-3. As a result, it lost part of the wing and ended up hitting the side of a rise backwards. The pilot died instantly. The plane, with its bow destroyed, slid down about 10 meters, losing its wings.

Despite the unfortunate accident, for which only the pilot was blamed, the G-9 had shown its excellent flying qualities. In the No.1 of the Magazine “Samoliot” of 1933 it was written:
“The G-9 built by Gribovski is an excellent glider. The large reserve of structural strength, necessary for drag and flight figures, did not greatly increase its weight or limit its flight capabilities. Its excellent stability and ease of handling make it an excellent flight planner. “

The excellent results obtained in the competition played an important role in the fate of the glider, which was built in series at the OSOVIAJIM Glider Factory until 1939, being considered one of the main Soviet gliders for trailing and flight training.

There are documented data on production in the Glider Factory until 1937 with the following distribution: 1933: 4, 1934: 43, 1935: 75, 1936: 110, 1937: 50. In total, 282 copies were built in these years. Production data for 1938 are not known.

In 1936 the Gribovski G-9 glider began to be built in Turkey, where Soviet specialists helped to develop sport gliding.

By the end of the Great Patriotic War the VVS had understood the importance of massive air landings using gliders. At that time it was necessary to have a robust and simple apparatus to train pilots of heavy landing gliders. At this point the G-9 was again remembered. On the basis of the few existing examples, the plans were reconstructed, from which a small series of gliders was built.

The Gribovski G-9 established several records were and it was used in the development of a series of experiments.

In 1933 the pilot Yudin made a towed flight of 3550 km. The pilot SN Anojin (later a test pilot and Hero of the Soviet Union), together with the pilot Gavrish, carried out inverted towing maneuvers on the G-9.

In 1934 Simonov set a world record for flight duration, covering 35 hours and 11 minutes of continuous flight.

Continuing the school figure execution records, the 200 figures executed by VA Stepanchonok would soon be surpassed by the results achieved by VG Borodin. Later Simonov would set another record by running acrobatic figures on the G-9 glider for 5 continuous hours, including 300 loops and 10 reversals.

The 5 of May of 1935 in Samara catching a G-9 was carried out by a Polikarpov U-2 flying at a speed of 120 km / h. The glider this time was piloted by Yudin and the tug plane by Borovkov. Later in Túshino, experiments were carried out to capture the glider in flight, being carried out by the pilots Vasyani and Boordin.

In 1938, a glider train made up of nine G-9 gliders towed from a Túpolev TB-1 bomber was presented during the air festival over Túshino A year later this story would repeat itself, but in this case with nine gliders.

In order to test the possibility of using gliders as an escape pod from stratostats in emergencies, a Gribovski G-9 was specially modified. The first test of this type was developed in 1936, when the glider, piloted Borodin, rose to the height of 2500 meters.

A second test took place on July 4, 1938, when the pilot V. Ílchenko was towed by the “CCCP VP-61” stratostat up to a height of 5100 meters and released, making a successful landing.

In 1936 the pilot PM Stefanovski reached the record height of 10360 meters in the G-9, towed by a Polikarpov I-15. A year later Flerov would surpass this mark when reaching 12,105 meters. On this flight the G-9 was towed by a Polikarpov RZ to a height of 8500 meters and then the glider ascended another 3605 meters while being towed. This was done with the help of a special tow cable designed by A. Ya. Scherbakov. At the time of takeoff, the glider was dragged by a normal 100-meter cable. Once a certain height was reached, when the wind turbulence disappeared, the new 0.2 mm steel cable was unwound, allowing the glider to increase the distance from the tugboat by 7000 meters.

G-9
Wingspan: 12.10 m
Wing area: 13.00 m²
Length: 5.77 m
Height: 1.45 m
Empty weight: 152 kg
Maximum takeoff weight: 230 kg
Wing loading: 17.7 kg / m²
Glide ratio: 17.50
Accommodation: 1
Stabilizers surface: 2.1 m²
Elevator area: 0.84 m²
Spoiler area: 1.72 m²

The G-7 (Russian: Грибовский Г-7) was a successful development of the previous types. As the tests of the high wing model G-6 did not bring the expected results, Gribovski decided to return to the configuration with mid wings, successfully tested on the G-2.

The G-7 glider was designed as a cantilever high-wing aircraft with medium deployment and E-385 profile. The wing had two wooden spars with a box-like structure and a sparse distribution of the wing rib. This characteristic caused the wing covering to form kind of waves on the wing surface.

The fuselage had a monocoque structure with plywood covering and its lower part ended in a ski, which guaranteed landing.

The tail was of the conventional monoplane type, with a very tall tail.

The pilot sat in an open cockpit just ahead of the wing’s leading edge.

The glider was designed and built at the Orenburg Flight School in 1929, during Gribovski’s years as an instructor. Due to the lack of space for construction, the group of enthusiastic builders relied on an abandoned church, working in the area of its bell tower. The different finished parts were lowered to the ground using ropes and then assembled.

In the VI National Competitions of 1929 Gribovski presented with the G-2 and G-6 models, participants in previous years and with the new G-7. Characteristic of Gribovski , the three designs stood out for their small dimensions, light weight and constructive simplicity.

The G-7 was one of the best gliders among the participants in the VI National Sailing Competitions, both for its stability in flight and for ease of control.

On October 16 1928, the pilot VA Stepanchonok tried to set a new flight record in this model. It originally took off from the north slope at 4:00 am, but the absence of wind caused the glider to soon descend. At 6:17 am he made the attempt again and this time with success. The glider stayed aloft throughout the day setting a Soviet record for flight duration of 10 hours 22 minutes. Throughout the day the average flight height did not exceed 150 meters. Only in late afternoon and with the appearance of some cloudiness, Stepanchonok managed to ascend to about 500 meters.

A year later the G-7 would participate again in the competitions. On this occasion it would once again be a reference by achieving a continuous flight of 23 hours and 40 minutes.

G-7
Wingspan: 14.50 m
Wing area: 15.00 m²
Length: 5.45 m
Surface of the horizontal plane: 2.16 m²
Vertical plane surface: 1.08 m²
Spoiler area: 2.2 m²
Aspect ratio: 14
Empty weight: 143 kg
Wing loading: 14.9 kg / m²
Glide ratio: 25.4
Accommodation: 1

The Gribovski G-6 (Russian: Грибовский Г-6) was designed as a record-setting glider taking into account the theoretical principles that established the superiority of the high wing for the glider’s flight conditions.

The G-6 was built entirely of wood. The G-6 glider differed from its predecessor G-2 fundamentally in the location of the cantilever wing in a high position behind the cockpit.

Its fuselage was covered with birch planks and featured an oval cross section and landing gear with a central ski.

The tail was of the conventional monoplane type, and maintained the high-rise tail of the G-2 glider.

The G-6 glider was painted dark cherry-red and in its bow section, on the left gunwale, an eagle was painted in flight with its wings spread.

The construction of the G-6 was started at the school in Orenburg in the winter of 1928 and by September of that year the glider could be successfully presented to the V National Sailing Competitions. At the end of the competitions, the G-6 was handed over to the Sinferópol Flight School.

A year later, in 1929, the G-6 would participate together with the G-2 and the G-7 in the VI competitions.

Despite showing acceptable results, the new scheme did not report noticeable advantages and for this reason this glider did not have a further development.

After long enough use the G-6 glider was damaged. It is known that its builder kept the piece of coating with the drawing of the eagle among his personal belongings for a long time.

G-6
Wingspan: 13.00 m
Wing area: 13.00 m²
Length: 5.00 m
Horizontal plane surface: 1.6 m²
Vertical plane surface: 0.7 m²
Spoiler area: 1.4 m²
Empty weight: 101 kg
Wing loading: 14 kg / m²
Glide ratio: 20
Accommodation: 1

After returning from the competitions in Koktebel in 1925, Gribovski was transferred to serve as an instructor at the Higher School of Aerial Shooting and Bombing known popularly as “Strelba” (Shooting), located in the city of Serpukhov.

Gribovski set to the construction of a new and improved competition glider known as G-2 (Russian: Грибовский Г-2). Like all Gribovski gliders, the G-2 was built entirely in wood and quite simply. The attachment points for the rudders and ailerons were quite simple and the attachments were made with normal screws. In his gliders Gribovski would hardly use welding, mainly due to the lack of a productive base with the necessary equipment.

The G-2 glider differed from its predecessor in its fuselage structure, constructed of birch planks and featuring an oval cross-section and landing gear with a central ski, which innovatively included air-cushioning using a bicycle inner tube.

The large wing was located in the middle position of the fuselage and was designed with the PR-385 wing profile. This wing consisted of two long trapezoidal consoles with rounded ends. Each console consisted of two box-type stringers, made of wood and 16 ribs. The entire forward part of the wing, up to the location of the second spar, was covered in plywood. From there and up to the trailing edge the covering would be made of fabric. This would be a distinctive feature of most of Gribovski’s wing designs. Long louvered ailerons were located on the wing trailing edge.

The tail was of the conventional monoplane type, with a very tall tail. The planes could pivot on their axis integrally, which, according to Gribovski, should facilitate the control of the glider. During the evaluation before the competition, the technical committee expressed doubts regarding the effectiveness of its short horizontal planes. Practice would show that they were unfounded.

The pilot sat in an open cockpit just ahead of the wing leading edge and was protected by a transparent celluloid windshield.

The G-2 glider was built in 1927, first flown that September, and successfully participated in the IV National Sailing Competitions held that year, showing quite good performance. The G-2 was the first Soviet glider capable of harnessing thermals for free flight.

On September 27, taking off in the valley, he managed to reach a good height and fly over the southern slope of the Klementiev Mountains. The flights carried out in the G-2 were noted for their good stability and behavior, which contributed to the popularity that the model would soon achieve. On October 4, flying from Klementiev Mountain, would land beyond the competition staff.

In 1928 the G-2 was the glider that opened the annual event at Koktebel. In these competitions Gribovski, taking advantage of a weak wind, took off from Feodosia and landed after traveling seven kilometers. The next flight on the G-2 ended with a landing over a vineyard, causing the glider to be damaged.

A year later the G-2 would appear again during the VI National Sailing Competitions, this time accompanying the G-6 and G-7 gliders.

Its results in the competitions in Koktebel between 1927 and 1929 were so positive that soon flying clubs throughout the USSR began to build it.

The 31 of October of 1932, during the VIII convocation of skills, the glider G-2, piloted by NG Baruzdin set a national record of a 43.5 km uninterrupted flight.

The G-2bis appeared in 1930 as an improved development of the G-2. The main changes introduced included a decrease in the sensitivity of the rudders to the controls.

This glider was built by a considerable number of sailing clubs and workshops throughout the country until a date as late as 1935.

Taking into account the popularity acquired by the model, the organization “Snabosoaviajim” developed the set of plans with explanation of the main construction details and assembly forms, which considerably facilitated the construction of the model in workshops and by aviation enthusiasts. The own “Snabosoaviajim”, predecessor of the Factory of Gliders of Túshino, built two copies of the model.

The G-2bis played a very important role in the preparation of the Soviet plane pilots. Despite being a somewhat difficult model to control in flight, it would become the main training glider in its time in the USSR. At the Kacha flight school instructors VA Stepanchonok and MA Nyuxtikov trained Soviet pilots in glide flight using this model.

The G-2bis would be used in the drag take-off tests carried out in Moscow by the pilot PM Stefanovski. For this purpose Gribovski developed a fixing system for the cable, which was successfully tested.

G-2
Wingspan: 13.00 m
Wing area: 14.00 m²
Length: 4.90 m
Height: 1.90 m
Empty weight: 98.5 kg
Wing loading: 12.7 kg / m²
Elevator area: 1.7 m²
Rudder surface area: 0.85 m²
Ailerons surface: 1.4 m²
Glide ratio: 18
Accommodation: 1

After his participation in the First National Gliding Competitions, held in Crimea, Gribovski entertained the idea of building a glider of his own design.

The Gribovski G-1 (Russian: Грибовский Г-1) was the first glider built by Vladislav Konstantinovich Gribovski. This glider was constructed entirely of wood and featured plywood and fabric overlay. Structurally, it was a high-wing cantilever-type monoplane with wing profile PR-426. The glider was noted for its constructive cleanliness.

The fuselage had a rectangular section with a forward cockpit for the pilot. The weight of the wing with the ailerons was 34 kg, while the fuselage and empennage weighed only 30 kg. A speed measurement instrument designed and built by Gribovski himself was installed on the G-1.

The tailplanes and empennage were highlighted by the large rudder area. A distinctive feature of this glider was the presence of a landing gear with wooden wheels, located on the sides of the fuselage, under the wing.

In the spare time that he was leaving the service and with the help of a group of colleagues who served in the same unit in Kiev, in the winter of 1924 – 1925 the glider was built.

In the fall of 1925 the Gribovski G-1 glider was included in the list of competitors of the III National Sailing Competitions in Koktebel. The evaluation committee made a positive assessment of the model.

The constructor carried out a series of short flights that demonstrated the rationality of the construction and quite acceptable flight characteristics.

On the 22 of September of 1925, dragging to the point of start, The G-1 was hit by a gust of wind land that launched it to one side, damaging it considerably. The wing was preserved, it suffered little and was later used by Professor VP Vietchinkin for static tests, which demonstrated the validity of its constructor’s calculations in relation to structural resistance.

G-1
Wingspan: 11.2 m
Wing area: 15.00 m²
Length: 5.3 m
Empty weight: 71 kg
Wing loading: 10.2 kg / m²
Elevator surface: 2.5 m²
Surface of the fixed part of the empennage: 0.34 m²
Rudder surface area: 1.2 m²
Spoiler area: 2.7 m²
Glide ratio: 5.2
Accommodation: 1

The Gribovski Biezprizornik (Russian: Грибовский “Беспризорник”) competition glider came from a Gribovski concept project. Its designer barely had time to pay attention to its construction, so it was decided not to include it in the numbering sequence of his creations. Rejected by his “father” the model would be jokingly nicknamed “Biezprizornik” (neglected or neglected).

The Biezprizornik construction was carried out by Groshiev, Sirken and Filyushkin, belonging to the Construction Bureau of the Union of Defense and Aviation Assistance Societies-Chemical Construction of the USSR (OSOVIAJIM).

Construction was carried out at the Moscow OSOVIAJIM Glider Factory during 1932.

Constructively, it was a high-wing monoplane with a sunshade, braced to the lower fuselage structure by four struts.

With the aim of reducing construction times and being able to participate in the 1932 competitions, instead of the original Gribovski wing, the brigade adapted the wing of an Antonov “Upar” (Ps-1) glider to the model. In its central part, this wing had a rectangular shape, but towards the ends the chord was tapering until it ended almost at a point. Much of the trailing edge of these outer sections was occupied by long louvered ailerons. The selected wing profile was the TsBPK (ЦБПК) and the entire construction was made of wood, with fabric covering.

The fuselage featured a hexagonal section with lightened frames and six stringers, constructed of 12 x 12 mm slats. Due to a mistake by the constructors, the glider received a too long nose, which resulted in a deterioration of its handling in turns. A landing skid was located in the ventral region of the fuselage.

The tail was of the monoplane type with a large area rudder attached to a small keel built integrally with the fuselage. The two horizontal planes shared a single spar. The assembly process for these plans was very labor intensive, as the builders left very small hatches on the sides for service.

The pilot was located in a cockpit just in front of the wing leading edge. The control from the cabin was carried out with the help of the lever and pedals. The transmission system to the ailerons was copied from that of the Antonov Us-4 and Ps-2 gliders. An interesting detail was that the bow, up to the first frame, could be pivoted open to one side, to give easy access to the control systems.

Gribovski, busy with the problems of keeping the MKB open, could not devote much attention to monitoring the construction, so he decided not to assign the glider its numbering, although he did not refuse to register it under his authorship.

The name “Biezprizornik” was given to the glider in jest. Once the initial tests were completed, the glider was sent in a railway car to the Koktebel Superior School of Planning . In some inexplicable way the glider got lost on the way and for about six months it travelled along the railroad tracks until it finally reached the school, well into 1933. The flight instructors at Koktebel decided to nickname it “Biezprizornik” in reference to the lack of a “Owner” who cares about his delivery for the competitions.

During the glider tests it was decided to change the wing attack angle, but this modification had little influence on the behaviour. The rudder control system had to be revised on several occasions and the ski was replaced, which suffered ruptures due to the great gap between its points of support and the lack of a suspension system.

It participated in the IX and X editions of the National Sailing Competitions. During the IX call the glider “Biezprizornik” would achieve the longest flight of the competition by staying in the air for 62 hours and 30 minutes.

The glider was used for several years as a trainer at the Koktebel High School of Planerismo. From 1933 on in the pilot training practice, aerobatic flights on gliders were included. The Gribovski G-9 and Sheremetiev Sh-5 gliders were used for this purpose. Preliminary preparation was carried out on the “Biezprizornik” glider and included the execution of barrels, eights and the entry training in thermal currents, with a duration of 5 hours of flight.

Only the one copy was built.

Biezprizornik
Wingspan: 13.8 m
Wing area: 17.00 m²
Length: 6.57 m
Height: 1.42 m
Empty weight: 117 kg
Wing loading: 11.0 kg / m²
Glide ratio: 15.20
Stabilizers surface: 1.1 m²
Elevator area: 0.85 m²
Empennage surface: 0.07 m²
Rudder surface area: 0.70 m²
Ailerons surface: 1.72 m²
Accommodation: 1