Bomber “131” , index inside OKB-1 EF-131 is a Soviet experienced jet bomber , created in OKB-1 by interned German scientists led by Brunolf Baade on the basis of a late project of the German jet bomber Ju 287 . Despite the promising layout, it was out of date almost immediately after the construction of the flight models, which, together with operational shortcomings, led to the closure of the project.
| EF-131 | |
|---|---|
 | |
| Type of | high altitude bomber |
| Developer |  OKB 1 |
| Manufacturer | OKB 1 ( Kazan ) |
| Chief Designer | Baade, Brunolf [1] [2] |
| First flight | May 23, 1947 |
| Status | was not adopted |
| Units produced | 3 prototypes |
| Base model | Ju 287 |
Development History
In 1944 , Junkers completed the construction of several prototypes of a promising jet bomber with a reverse sweep wing , Ju 287. Each of the five prototypes differed in the layout scheme, for example, the Ju-287V1 had four turbofan engines - two in nacelles on the wing and two in front of the fuselage. To speed up the work, parts from ready-made German or downed American bombers were used, in particular, the chassis from the B-24 and the fuselage from He 177 [3] . In total, the prototypes completed 17 flights.
After the surrender of Germany, Soviet troops in Dassau captured the unfinished Ju-287V1. In parallel, a gathering of German specialists in various fields was carried out. At the beginning of 1946, the NKVD conducted an operation to collect and recruit aviation specialists, since work in the aviation sector of former German specialists was directly prohibited, as a result, a significant part of the aviation engineers was taken to Podberezye near Moscow [4] , where they provided comfortable living and working conditions. The production base for the still nameless design bureau was sections of aircraft factory No. 256. At the end of 1946, German specialists were divided into OKB-1 and OKB-2 [5] . OKB-1, which consisted of Junkers employees, was headed by Dr. Brunolf Baade , a wing sweep specialist who had previously worked in the Junkers design bureau; the field of activity of this bureau was heavy aircraft [5] .
The most promising of German projects was recognized as the Ju 287 variant with six Jumo 004 turbofan engines under the wing, grouped in three (Ju 287V3) [6] [7] . On April 17, 1946, by a closed decree of the Council of Ministers of the USSR No. 874-266, a team of German specialists led by Baade was instructed to develop and build a bomber based on the Ju 287 [7] . Three prototypes were completed by German specialists back in Germany and transported to the USSR in disassembled condition [6] . Calculations made at TsAGI determined the maximum speed for an aircraft with a reverse sweep wing at 0.95M. However, it was not possible to provide sufficient wing rigidity, which led to a decrease in the sweep angle [6] . Until the spring of 1947, conditions were created for the work of the OKB in the USSR, and only in March 1947 the work was “legalized” by a decree of the USSR government on the development of the “131” bomber [7] . The first flight took place on May 23, 1947 with a German crew, while on the run due to damage to the right landing gear, the plane touched the ground with a wing [8] .
Soon the work was suspended TsAGI due to insufficient strength of the fuselage and the airframe, after refinement, the tests were continued. However, in their course, constant shimmy oscillations were revealed - a longitudinal uncontrolled buildup [6] . In addition, the flights were accompanied by strong vibration. In October 1947, after checking the technical condition, numerous damage to the rubber parts and seals of the aircraft were discovered, in addition, the wiring deteriorated [9] . All prototypes were sent to the factory for repair and refinement for the next test cycle, scheduled for the summer of 1948 [9] . However, they never began - by the Minaviaprom decree of August 23, 1948, all work was stopped. One of the prototypes was subsequently used to build the 140 bomber [9] .
Armament
The defensive armament of the aircraft consisted of two 13-mm MG 131 machine guns grouped into a tail turret. The bomb load could reach up to two thousand kilograms [9] .
Features
Data Source: [6] [9]
- Specifications
- Crew : 4 people
- Length : 20.47 m
- Wing span : m
- Height : 5.7 meters
- Maximum take-off weight : 23,000
- The mass of fuel in internal tanks: 7150 kg
- Powerplant: ×
- Thrust : × 6x900
- Flight characteristics
- Maximum speed:
- by the ground: 855 km / h
- at an altitude of 2000 m: 865 km / h
- Practical range: 1710 km
- Practical ceiling : 12,500 m
- Climb time 1000 meters: ??
- Takeoff run: 1820 meters
- Mileage: 860 meters
- Armament
- Suspension points: bomb bay
- Bombs : up to 2000 kg
Machine rating
Despite the promising layout, the EF-131 had a number of inherent flaws. For 1947, Jumo 004 engines were already obsolete - Soviet developments, AM-TKRD-01 and AL-02 had higher rates [9] . In addition, the reverse sweep wing caused longitudinal buildup and strong vibration. Together with characteristics that generally did not meet the rapidly growing requirements for a jet bomber [3], this led to the closure of the program in favor of further development based on the EF-131, similar in layout to the 140 bomber [9] [6] .
Notes
- ↑ Gordon, 2002 , p. 53.
- ↑ Sultanov I., 1995 , p. four.
- ↑ 1 2 Sultanov I., 1995 , p. 3.
- ↑ Alekseev, 1993 , p. eight.
- ↑ 1 2 Sultanov I., 1995 , p. 2.
- ↑ 1 2 3 4 5 6 Vasiliev N., 2003 , p. 18.
- ↑ 1 2 3 Gordon, 2002 , p. 32.
- ↑ Gordon, 2002 , p. 32-33.
- ↑ 1 2 3 4 5 6 7 Gordon, 2002 , p. 33.
Literature
- Alekseev S.M. Deportation. How scientists from Nazi Germany built planes in the USSR. // Airplanes of the world. - 1993. - No. 11 .
- Vasiliev N. Front bomber with reverse sweep wing. About Soviet-German aircraft EF-131 and EF-140 // Wings of Russia. - 2003. - No. 2 .
- Paramonov V.N. DAILY LIFE OF GERMAN SPECIALISTS IN THE SOVIET CITY (1946–1953) // Bulletin of the Humanitarian Institute. - 2008. - No. 1 (3) .
- Berne L.P. Review of the book. Sobolev D. A. "The German footprint in the history of Soviet aviation. On the participation of German specialists in the development of aircraft manufacturing in the USSR." // Bulletin of the Humanitarian Institute. - 1998. - No. 3 .
- Sultanov I. German Design Bureau in the USSR // Aircraft of the world. - 1995. - No. 1 .
- Antseliovich L. Unknown Junkers. - Moscow: EKSMO, 2012 .-- 143 p. - ISBN 978-5-699-58507-6 .
- Gordon, Yefim. Early Soviet Jet Fighters. 1940s and Early 1950s. - Hinckley, England: Midland Publishing, 2002 .-- 143 p. - ISBN 1-85780-139-3 .