Beriev R-1

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Beriev R-1 (RI)
f2
Type: Flying boat
Design country:

Soviet Union 1923Soviet Union Soviet Union

Manufacturer:

OKB Beriev

First flight:

May 30, 1952

Number of pieces:

1 prototype

The Beriev R-1 ( Russian Бериев Р-1 ) was the first jet-powered flying boat in the Soviet Union.

History and Development

After the end of the Second World War , the OKB -49 began developing Project R. Starting in May 1947, work began on the wing design of the Beriev Be-6 , the requirement for a jet flying boat by the Soviet Navy and the jet aircraft developments in the OKBs Ilyushin and Tupolev a corresponding draft.

The official requirement was published on June 12, 1948 and provided for a range of 2000 to 2500 km, a crew of three and a speed of 800 km / h. The aircraft should carry a radar device. The task was the reconnaissance and the fight against enemy targets. For this purpose, four 20 mm cannons and a bomb load of 2,000 kg were provided.

On June 10, 1950, a dummy was ready. The originally planned Rolls-Royce Nene engines were replaced by the now available Klimow WK-1 , which generated a higher thrust. They were built into long panels that were located at the kink of the wing and thus had a maximum distance from the water surface. In addition, the installation of a jump start rocket engine was possible. Instead of the 20 mm cannons, 23 mm caliber cannons should be used. In addition, it was possible to transport two 500 kg mines.

In November 1951 the first prototype was ready and on November 24th the first experiments in the water began. At 165 km / h there were uncontrollable vibrations around the pitch axis, which almost led to the destruction of the prototype . The phenomenon was called the “hydrodynamic instability threshold”, and extensive research was required to solve it. The solution was a system that allowed air to flow under the hull between the two boat stages .

During the first flight , which took place on May 30, 1952, vibrations occurred at the stern. Even at high speeds on the water, there were vibrations that assumed critical proportions. On October 3, 1953, the prototype had an accident during the landing, but could be repaired again. The project was already at risk at this point. A quick solution to the problem did not seem likely. The development of long-range land-based reconnaissance aircraft made flying boats generally appear superfluous in the future.

However, it was decided to transfer the knowledge gained into a more powerful project, from which the Beriev Be-10 emerged. The flights of the modified R-1 were resumed on July 18, 1953. Improved slats had been installed. Eventually they managed to modify the air flow system so that it also prevented the vibrations. Considerations were made to equip the machine with a swept tail unit, but this was not pursued after the construction of a dummy. Series production of this type was no longer planned at that time.

The modified machine continued to be used in test operations without any problems until in February 1956 the R-1 had to be written off after it had hit the ground as a result of an emergency landing.

construction

The R-1 was a shoulder- wing monoplane with a cantilevered trapezoidal wing and folding floats at the wing tips. It had a pressurized cabin , ejection seats for the pilots and a remote-controlled tail stand for defense. The cockpit was shifted to the left for a better view of the pilot. The tail unit was designed in a T-shape. The hull was designed in two stages. The machine, equipped with radar , was suitable for all weather conditions.

Technical specifications

Parameter Data
length 19.90 m
span 20.00 m
21.40 with folded floats
height 7.10 m
Wing area 58.2 m²
Empty mass 12,460 kg
Takeoff mass normal 17,000 kg
maximum 20,300 kg
drive two Klimow WK-1s , each with a starting thrust of 26.4 kN
Top speed 810 km / h at an altitude of 7,000 m
Cruising speed 760 km / h
Take-off speed 195 km / h
Landing speed 185 km / h
Range 2,000 km
Service ceiling 11,500 m
Armament two rigid 23 mm cannons in the front of the fuselage
two movable 23 mm cannons in the stern
an additional 1,000 kg of drop ammunition
crew 3

See also

literature

Web links