OKB-1 EF 131

EF 131
Role	Bomber
National origin	USSR
Manufacturer	GOZ-1
Designer	Dr. Brunolf Baade
First flight	23 May 1947
Retired	1948
Status	Cancelled
Number built	1
Developed from	Junkers Ju 287
Variants	OKB-1 140

The OKB-1/Junkers EF 131 was a jet bomber produced in Germany and the USSR from 1944. It was cancelled in August 23, 1948, after further work was stopped on the aircraft.

Development

The EF-131 was developed based on fragments of project documentation for the Ju 287 after the Red Army captured the Junkers factory in Dessau. The first prototype was built from components of the Junkers Ju 287 V2 and V3, the second and third prototypes (V – Versuchs – test/research/prototype) of the Luftwaffe's radical forward-swept-wing jet bomber. The V2 was nearly complete before the end of World War 2, but was hidden in the forest at Brandis along with Ju 287 V1 and eventually blown up by the Germans to avoid capture by US forces, and remnants of it, including wing sections, were taken into Red Air Force hands under military intelligence supervision along with the skeletal airframe of the unfinished V3.^[1] The V3 was to have been the first 287 to be made to pre-production model specifications, and the eventual EF-131 was almost identical to it in terms of overall design, except in having a slightly longer fuselage. The airplane was completed in the Soviet zone of occupied Germany, but was dismantled and transported to GOZ-1, (Gosudarstvenny Optniy Zavod – state experimental plant), at Dubna near Moscow, because the victorious Allies forbade the construction and testing of aircraft in occupied Germany. OKB-1 at GOZ-1 was formed with Dr. Brunolf Baade as the chief designer, and a very talented team of German engineers seconded by the Soviet government. Extreme pressure was applied to get the aircraft ready to appear in the 1947 Aviation Day fly-past at Tushino airfield, but several factors combined to prevent the EF-131 from appearing.^[2]

Flight testing in the USSR began on 23 May 1947, at the LII airfield, after the airframe had been strengthened to meet the requirements of a TsAGI(Tsentralniy Aerodinamicheskiy i Gidrodinamicheskiy Institut- central aerodynamics and hydrodynamics institute) structural survey, which revealed major weaknesses of the airframe. The first flight resulted in the port undercarriage collapsing due to a bolt failure, subsequent flight tests revealed major deficiencies such as nosewheel shimmy and tail surface vibration. Rectification of the defects caused many delays but the worst delays were caused by bureaucracy when it was decreed that foreign workers could not work at the LII airfield.^[2]

The aircraft sat at LII over the winter but the harsh conditions caused the deterioration of rubber components and wiring, which required lengthy repairs. Preparations for resuming flight tests were almost complete in June 1948 when Ministry of Aircraft Industry Order No. 440 ordered that further work on the EF-131 be discontinued, termination of the programme being confirmed by resolution No.3206-1301 issued on 23 August 1948.^[2]

The EF-131 had become obsolete as newer Soviet-built engines with better performance became available. The airframe of the second prototype was used for the 140 programme.^[2]

Specifications (EF 131)

Data from ^[2]

General characteristics

Crew: 3
Length: 20.47 m (67 ft 2 in)
Wingspan: 19.4 m (63 ft 8 in)
Height: 5.7 m (18 ft 8 in)
Airfoil: root: Ju 0.9 23 10.7-0.825-40 ; tip: Ju 0.9 23 12.7-0.825-40^[3]
Empty weight: 11,900 kg (26,235 lb)
Gross weight: 22,955 kg (50,607 lb)
Powerplant: 6 × Junkers Motoren Jumo 109-004 turbojet engines, 8.829 kN (1,985 lbf) thrust each

Performance

Maximum speed: 860 km/h (530 mph, 460 kn)
Range: 1,710 km (1,060 mi, 920 nmi)
Service ceiling: 12,500 m (41,000 ft)

Armament

Guns: 2 x 13mm machine-guns in a remotely controlled tail barbette
Bombs: 2,000kg (4,410 lb) of bombs in an internal bomb bay

References

^ Lommel, Horst, 2004. Junkers Ju 287: The World's First Swept-Wing Jet Aircraft. Atglen, PA: Shiffer Publishing, Ltd.
^ ^a ^b ^c ^d ^e Gordon, Yefim (2004). Early Soviet jet bombers : the 1940s and early 1950s. Hinkley: Midland. ISBN 1-85780-181-4.
^ Lednicer, David. "The Incomplete Guide to Airfoil Usage". m-selig.ae.illinois.edu. Retrieved 16 April 2019.

Bibliography

Gunston, Bill. "The Osprey Encyclopaedia of Russian Aircraft 1875–1995". London, Osprey. 1995. ISBN 1-85532-405-9
Gordon, Yefim. "Early Soviet Jet Bombers". Hinkley, Midland. 2004. ISBN 1-85780-181-4

External links

https://www.webcitation.org/5knuWmxmR?url=http://www.geocities.com/hjunkers/ju_ef131_a1.htm

[1] Lommel, Horst, 2004. Junkers Ju 287: The World's First Swept-Wing Jet Aircraft. Atglen, PA: Shiffer Publishing, Ltd.

[Gordon-2] Gordon, Yefim (2004). Early Soviet jet bombers : the 1940s and early 1950s. Hinkley: Midland. ISBN 1-85780-181-4.

[Selig-3] Lednicer, David. "The Incomplete Guide to Airfoil Usage". m-selig.ae.illinois.edu. Retrieved 16 April 2019.

[1]

[2]

[3]

v t e Junkers aircraft
Company designations	J 1 J 2 J 3 J 4 J 5 J 6 J 7 J 8 J 9 J 10 J 11 J 12 F 13 J 15 K 16 K 17 J 18 T 19 A 20 H 21 / J 21 / T 21 J 22 T 23 G 23 F 24 / G 24 A 25 T 26 T 27 J 28 T 29 K 30 G 31 A 32 W 33 W 34 A 35 S 36 K 37 G 38 K 39 K 47 A 48 J 49 A 50 K 51 K 53 K 85
Company EF designations (experimental aircraft)	EF 29 EF 31 EF 52 EF 61 EF 72 EF 73 EF 74 EF 77 EF 94 EF 126 EF 127 EF 128 EF 130 EF 131 EF 132 EF 140 EF 150
Idflieg designations	CL.I CLS.I D.I E.I E.I (2) J.I
RLM designations	Ju 46 Ju 49 Ju 52 Ju 60 Ju 85 Ju 86 Ju 87 Ju 88 Ju 89 Ju 90 Ju 160 Ju 187 Ju 188 Ju 248 Ju 252 Ju 268 Ju 287 Ju 288 Ju 290 Ju 322 Ju 352 Ju 388 Ju 390 Ju 452 Ju 488 Ju 635

Development

Specifications (EF 131)

See also

References

Bibliography

External links