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OKB-1 EF-140

Soviet Union (1948)

Detailing the development and operational history of the OKB-1 EF-140 Jet-Powered Tactical Fast Reconnaissance / Bomber Prototype.

 Entry last updated on 4/5/2016; Authored by Staff Writer; Content ©www.MilitaryFactory.com



  OKB-1 EF-140  
Picture of OKB-1 EF-140 Jet-Powered Tactical Fast Reconnaissance / Bomber Prototype


The Soviet OKB-1 EF-140 jet-powered bomber prototype emerged from work immediately done after the close of World War 2.

The EF-140 was a Soviet post-World War 2 jet-powered tactical bomber design continuation of the line begun with the capture of the German Junkers Ju 287. The Ju 287 was one of the more unique of the German wartime jet-powered aircraft in development before the close of the war in 1945 - particularly in its use of advanced swept-forward wings as well as jet propulsion technology. The Junkers product was furthered into the local Soviet "EF-131" which completed a hasty first flight in 1946 with more formal testing had in 1947. Though the project was terminated in 1948, the second airframe of the EF-131 made up the basis for the evolved EF-140.

The EF-140 initially existed as a tactical bomber like the EF-131 before it. However, whereas the EF-131 relied on now-obsolete German Junkers Jumo turbojets (a total of six such systems powered the original aircraft), the EF-140 introduced Soviet engines of a more advanced, capable nature. Design of the new aircraft commenced in 1947 and the EF-131 was modified to carry 2 x Mikulin AM-TKRD-01 axial flow turbojet engines. The forward-swept wings remained in play with the engines slung underneath and the crew of three was increased to four. Dimensions included a length of 62 feet, a wingspan of 71.8 feet and a height of 18.5 feet. Fixed armament became four guns (largely defensive in nature) with two guns held in a dorsal barbette and two guns fitted to a ventral barbette. Both barbettes would be remote-controlled and aimed by way of periscopes. An internal bomb bay would hold several thousand pounds of conventional drop ordnance.

The initial EF-140, born from the second EF-131 prototype while carrying the Mikulin engines, was made ready for September 1948 and completed its first flight on September 30th. From this, thought came to rework the EF-140 as a tactical fast-reconnaissance platform and this produced the "EF-140R" model in turn. Engines were changed to 2 x Klimov VK-1 units (5,950lb thrust each) and wingtip fuel tanks were added to increase operational ranges. Other refinements were enacted on the overall design including revised turrets.

Flight testing at GOZ-1 revealed issues with wing flutter which brought the design back to the engineering boards. The final iteration of the line came in the proposed "EF-140B/R" which was to be a fast-reconnaissance platform with bombing capability as secondary. The engines remained the same Klimov units as in the earlier model and the program progressed enough to begin ground testing before the end. However development was terminated on both prototypes in June of 1950 in favor of more advanced, capable bomber / reconnaissance platforms.
Any available statistics for the OKB-1 EF-140 Jet-Powered Tactical Fast Reconnaissance / Bomber Prototype are showcased in the areas immediately below. Categories include basic specifications covering country-of-origin, operational status, manufacture(s) and total quantitative production. Other qualities showcased are related to structural values (namely dimensions), installed power and standard day performance figures, installed or proposed armament and mission equipment (if any), global users (from A-to-Z) and series model variants (if any).
OKB-1 EF-140R Specifications
National Flag Graphic
Soviet Union
Year: 1948
Type: Jet-Powered Tactical Fast Reconnaissance / Bomber Prototype
Manufacturer(s): GOZ-1 - Soviet Union
Production: 2
Supported Mission Types
Air-to-Air
Interception
Unmanned
Ground Attack
Close-Air Support
Training
Anti-Submarine
Anti-Ship
Airborne Early Warning
MEDEVAC
Electronic Warfare
Maritime/Navy
Aerial Tanker
Utility/Transport
Passenger Industry
VIP Travel
Business Travel
Search/Rescue
Recon/Scouting
Special Forces
X-Plane/Development
Structural
Crew: 4
Length: 63.16 ft (19.25 m)
Width: 71.75 ft (21.87 m)
Height: 18.54 ft (5.65 m)
Empty Weight: 32,353 lb (14,675 kg)
MTOW: 56,317 lb (25,545 kg)


Installed Power
2 x Klimov VK-1 turbojet engines developing 5,950 lb of thrust each.

Standard Day Performance
Maximum Speed: 522 mph (840 kph; 454 kts)
Maximum Range: 2,237 mi (3,600 km; 1,944 nm)
Service Ceiling: 46,260 ft (14,100 m; 8.76 mi)


Armament
STANDARD:
2 x 23mm cannons in dorsal turret
2 x 23mm cannons in ventral turret

OPTIONAL:
Up to 8 x 220lb bombs carried.


Operators List
Soviet Union (cancelled)

Series Model Variants
• 140 - Base Series Designation; fitted with 2 x Mikulin AM-TKRD-01 turbojet engines.
• 140-R - Reconnaissance conversion of the 140; fitted with Klimov VK-1 series turbojet engines.
• 140-B/R - Second prototype; reconnaissance-bomber form.


Supported Weapon Systems
Graphical image of an aircrat automatic cannon
Graphical image of an aircraft conventional drop bomb munition