Yakovlev Yak-38

Yakovlev Yak-38
Jak-38 of the flight deck cruiser Novorossiysk of the Soviet Pacific Fleet (1984)
Type:	VTOL - fighter aircraft
Design country:	Soviet Union
Manufacturer:	OKB Yakovlev
First flight:	1971
Commissioning:	1977
Production time:	From 1975 in series production
Number of pieces:	231

The Yakovlev Yak-38 ( Russian Яковлев Як-38 , NATO reporting name Forger ) was the first VTOL - combat aircraft of the Soviet Union . Another designation was Jak-36MP (Як-36МП). The Jak-38 is a vertical take- off aircraft in a lift and lift / thrust engine arrangement. The vertically installed lift engines are only used in hover flight and in the transition from or to level flight and are otherwise switched off.

history

Jak-36

The aircraft is based on the Jak-36 technology demonstrator . After its successful presentation, the construction of further helicopter carriers of the Moskva-class was abandoned and instead the Kiev-class was favored.

The project started in 1967 under the direction of Stanislaw G. Mordovin and project engineer O. A. Sidorow, to whom Viktor N. Pavlov joined in autumn 1967, with the designation Jak-36M. The official development contract was given by the Council of Ministers on December 27, 1967. Alexander Yakovlev gave his approval for the designs in August 1968, and in January 1969 the requirements document was signed with the Soviet Air Force . It required a top speed of 1400 km / h and a range of 700 km with a 1000 kg payload. The aircraft should in principle serve to combat fixed and mobile ground and sea targets within sight, from opposing helicopters, reconnaissance and transport aircraft, and for reconnaissance purposes. Construction of the first prototype and the first mock-up began during the same period . In April 1970 the mockup and the first prototype were completed. After the prototype had been delivered, the first tests of the lift drive began in Schukowski on a special test structure that held the aircraft over the ground with ropes. The prototype of the Yak-38 lifted off the ground for the first time on September 22, 1970 with Valentin Grigoryevich Muchin ( Russian Валентин Григорьевич Мухин ) on board. The first tests showed a tendency to rock due to insufficient steering effect, especially around the roll axis. The engineers then modified the nozzles on the wing tips so that their airflow could be directed upwards and downwards. In October 1970 the second prototype was then slightly modified (longer nose) completed and at the end of November 1970 or beginning of December the first, very short or longer flight with conventional take-off and landing of a Jak-36M took place. On July 13, 1971, the manufacturer's tests were completed and the now three prototypes were used for state acceptance tests. These were continued until October 1973, with test flights also taking place on a replica flight deck in 1972. Since the Kiev was still under construction, the first carrier tests were carried out on board the helicopter carrier Moskva . For this purpose, a 20 m × 20 m platform was installed in the middle of the ship's flight deck. The first landing on the ship was carried out on November 18, 1972 by the test pilot Michail Deksbach. The first machine of the trainer version Jak-38U was completed in November 1974. In December 1974, the Jak-36M were officially accepted and production approval was given. Experiments on board VTOL aircraft carriers were observed from 1975 onwards.

Series production started in May 1974, with one of the first machines crashing on April 4, 1975 due to an engine failure. In 1975, the 279th Independent Airborne Attack Regiment (OKSchAP) set up the first operational unit of the Jak-38, which began training in December. In 1976 the association was transferred to the Northern Fleet and its home base was Severomorsk. In the same year, the 311st Regiment was set up for the Pacific Fleet with Vladivostok as its future home base, as well as the 299th Regiment, which was stationed on the Novofyodorowka base near Saki in the Crimea and was mainly intended for training purposes. The training complex for the Soviet naval aviators was built at this location, including the runway modeled on the carrier ships. On August 11, 1976, the former Jak-36M was officially put into service as Jak-38. There were about 75 Yak-38, including a small number of two-seat training aircraft produced Yak-38U. Other sources speak of 231 aircraft produced. In line with the fighter aircraft, the trainers also received various improvements in the course of production, such as additional openings on the air inlets or air baffles and rails under the fuselage and on the air inlets in order to better deflect air turbulences and increase lift. The planes were stationed on the four VTOL flight deck cruisers of the Kiev class . The deployment in Afghanistan showed the weaknesses of the design in the form of unacceptable hot-and-high capabilities and a payload that was too low. In August 1981, a further development was decided, the capabilities of which were established in October 1982. The first flight tests of the prototype took place in November 1982. In the middle of 1983 the manufacturer tests were completed and the production approval was given. Series production began in 1984; thus the Jak-38M, equipped with a more powerful main engine and optional additional tanks, was put into service. After 50 machines, production was stopped in 1988 and the aircraft carriers with their Jak-38s were also decommissioned in the mid-1990s.

technology

Engine arrangement

Yak-38 in flight

Yak-38 on the deck of Novorossiysk

The two-seat school version Jak-38U

The Jak-38 is an all-metal construction made of aluminum and aluminum-lithium alloys , with high-strength steel and titanium alloys also being used for certain components and glass fibers for the radome. The half-shell hull is a normal construction with frames and stringers . In the section behind the nose a part of the avionics and in the lower part one of the nozzles for the control of the hover flight were accommodated. This is followed by the cockpit with the nose landing gear housed underneath, followed by the second part of the avionics and the air inlets attached to the side of the fuselage. This is followed by the section for the lifting engines, the reinforced and insulated rear walls of which serve as thermal protection for the adjoining front fuselage tank.

Evaluation and succession

Due to its low speed and range, it was initially classified by NATO as very weak. It was believed that in a dogfight it would have been inferior to most western carrier aircraft . Experience in the Falklands War showed, however, that the British Harrier fighter aircraft of the Royal Navy used there , which had flight performance comparable to that of the Jak-38 , could hold their own against the Argentinian Dassault Mirage III fighter aircraft, which are classified as much more powerful . This was due to their modern air-to-air missiles and tactical air combat maneuvers using the swiveling engine outlets in flight, maneuvers that conventional fighters were unable to perform.

The combat value of the Jak-38 was corrected upwards in relation to the range when the machines were located much further away from their aircraft carriers than was thought possible. The Soviet naval aviators now also mastered the roll-in start and were thus able to save a lot of fuel during take-off. Nevertheless, the Yak-38 of the Harrier was inferior by its weaker engine and the lower payload and range. Despite the improvements introduced with the Jak-38M, the aircraft was judged to be too small to meet the requirements of the Navy, which is why the development of a 15 to 20-ton successor model began as early as the mid-1970s. However , the Jakowlew Jak-141 developed by OKB Jakowlew was not put into service.

The Jak-38 received an automatic rescue system for the hover flight and transition phase with the ejection seat K-36WM , which can be triggered both by the pilot and by an automatic system that detects abnormal flight conditions. The aircraft catapulted the pilot out of the aircraft without his intervention as soon as it rolled more than 60 degrees in the lift phases (up to a pivoting of the thrusters to the horizontal at 67 degrees) . When the automatic rescue system of the Yak-38 was triggered during the hovering and transition phase, all of the pilots involved survived. The system was taken over from the Jak-36, in which it was necessary because of the immediate roll movement if one of the two adjacent engines failed.

Technical specifications

Three-sided view of the Jak-38

Parameter	Jak-38	Yak-38M	Jak-38U
crew	1		2
length	16.37 m		17.76 m
span	7.02 m
height	4.25 m
Wing area	18.69 m²
Wing extension	2.9
Empty mass	6555 kg		8390 kg
Takeoff mass	VTO max. 11,300 kg	VTO ​​max. 12,000 kg	VTO ​​max. 10,000 kg
Load factor	6 g		3 g
Top speed	1150 km / h 978 km / h (at sea level)	1210 km / h	900 km / h
Service ceiling	11,000 m	12,000 m	6000 m
Range	860 km 370 km (with max. Weapon load)	1000 km
Engines	a Tumanski R-27W-300 , 59.84 kN thrust two Kolessow RD-36-35FW hoist engines , 29.9 kN each	a Tumanski R-28W-300 , 63.8 kN thrust two Kolessow RD-38 hoist engines , each 31.9 kN thrust	a Tumanski R-27W-300, 59.84 kN thrust two Kolessow RD-36-35FW hoist engines, 29.9 kN each
Armament	Max. 1700 kg for a 600 m taxiway 600 kg for vertical takeoff 500–600 kg at high temperatures and 200 m taxiing distance	Max. 2000 kg	no

Armament

Yak-38 on the deck of the Minsk 1983, each armed with two R-60 missiles

Jak-38 as an exhibit, armed with one UB-16-57UMD-73 launcher for 16 57 mm missiles and one UB-32A-73 launcher for 32 57 mm missiles

Gun load of 2000 kg at four underwing stations

Air-to-air guided missile

• 2 × APU-60-1 starter rails, each with a Wympel R-60 (AA-8 "Aphid") - infrared controlled for short distances
• 2 × BD-60-21U starting rails, each with a Wympel R-3/13 (AA-2 "Atoll") - infrared-guided, self-targeting for short distances

Air-to-surface guided missile

• 2 × Swesda Ch-23M (AS-7 "Kerry") - radio-controlled (steering system: DELTA-NG)

Unguided air-to-surface missiles

• 2 × UB-32A-73 rocket tube launch container with 32 unguided S-5 air-to-surface rockets each ; Caliber 57 mm
• 2 × UB-16-57UMD-73 missile tube launch container with 16 unguided S-5 air-to-surface missiles each; Caliber 57 mm
• 2 × Wympel B-8W20A1 rocket tube launch container for 20 unguided air-to-ground missiles S-8 in caliber 80 mm
• 4 × APU-68UM3 launch rails, each with 1 unguided air-to-surface missile S-24B ; Caliber 240 mm (235 kg)

Unguided free-fall bombs

• 2 × Basalt FAB-500-M62 (500 kg free-fall bomb )
• 2 × ZB-500RT (450 kg napalm bomb )
• 2 × basalt FAB-250-M54 (250 kg free-fall bomb)
• 2 × BetAB-250 (250 kg anti-slope bomb )
• 2 × multiple bomb carriers MBD, each with 5 × FAB-100 (100 kg free-fall bomb)
• 1 × RN-28 (tactical 1-kt free-fall nuclear bomb )
• 1 × RN-40 (30 kt tactical free-fall nuclear bomb)
• 1 × RN-41 (tactical free-fall nuclear bomb)

External container

• 4 × UPK-23-250-machine gun containers each with 1 double-barreled 23-mm -Maschinenkanone GRYAZEV-SHIPUNOV GSH-23 L with 250 rounds of ammunition (Splitterspreng- and tank fire projectiles)
• 2 × drop-off additional tanks PTB-500 for 500 liters of kerosene
• 1 × Tekon / Elektron APK-9E radio data transmission container as a relay for the steering signals for the Ch-23

literature

• Heiko Thiesler: Surprise on the Bosporus: Jakowlew Jak-38 . In: FLiEGERREVUE X . No. 61 . PPV Medien, Bergkirchen 2016, p. 82-96 .

Web links

Commons : Jakowlew Jak-38  - Collection of pictures, videos and audio files

Individual evidence

1. ↑ details of the Yakovlev design office. Archived from the original on July 26, 2013 ; accessed on March 23, 2020 . 
2. ↑ ^{a b c} Jefim Gordon : Yakovlev Yak-36, Yak-38 & Yak-41 . The Soviet Jump Jets. In: Red Star . Midland Publishing, 2008, ISBN 978-1-85780-287-0 , pp. 144 (English: Yakovlev Yak-36, Yak-38 & Yak-41 .).
3. ↑ ^{a b c d e f g h} Heiko Thiesler: Surprise on the Bosporus: Jakowlew Jak-38 . In: FLiEGERREVUE X . No. 61 . PPV Medien, Bergkirchen 2016, p. 82-96 .
4. ↑ wordpress.com: Sea Harrier FRS.1 vs. Yak-38 'Forger' | Defense of the Realm , accessed October 30, 2016
5. ^ Martin J. Dougherty: Aircraft . The Rosen Publishing Group, 2012, ISBN 978-1-4488-9246-4 , pp. 39 ( limited preview in Google Book search).
6. ^ Riccardo Niccoli: Airplanes: The most important types of aircraft in the world . Kaiser, ISBN 3-7043-2188-5 , p. 215 .