General Electric J-79 Jet Engine (F-104 and F-4 fighters backbone of NATO)
From: http://forum.keypublishing.com/showthread.php?31570-soviet-russian-engines
Well, there are some interesting stories in Russian engine development, to be sure.
For example, everyone knows that they got the Nene and Derwent from Britain, which were reverse-engineered and put into production. Less well known engine technology transfers occurred. The two F-86s (1 A, 1 E) recovered from Korea were actually going to be reverse engineered, but this project was canned- but
the reverse-engineered AN/APG-30 ranging radar formed the basis of the SRD-3 "Grad" which equipped the MiG-19. Ironically by the time these jets met American Phantom over Vietnam, the F-4 lacked a gun, and when they did strap on a gun, it lacked a gunsight radar ranging mode, unlike the F-105 which actually had a daylight dogfight capability, though without quick turn capability.
I suspect, though I haven't seen it formally acknowleged, that the J47 of the F-86 was at least studied, though it wasn't actually copied.
More seriously, the AL-21F was heavily based on a J79 turbojet recovered from Vietnam. It is a measure of the technology gap that an American engine almost 10 years old was worth reverse engineering. The original AL-21F wasn't very successful, but was developed into the AL-21F-3 which as classified secret and rarely exported- perhaps to hide the ancestry of the Russian's most advanced turbojet of the time.
Aircraft Propulsion and Gas Turbine Engines
https://books.google.com/books?isbn=1420008773
Ahmed F. El-Sayed - 2008 - Technology & EngineeringThe engine was adopted for the Tupolev Tu-128P in 1960. The Lyulka AL-21 is closely similar to the GE J-79. It entered the service in early 1960s as it powered ...
Variable stator led to GE J-79 first true engien for supersonic flight. powered F-4 Phantom .. The Lyulka AL-21 is closely similar to the GE J-79. . It entered the service in early 1960s as it powered ... TU-28P
http://forum.keypublishing.com/showthread.php?31570-soviet-russian-engines
More seriously, the AL-21F was heavily based on a J79 turbojet recovered from Vietnam.
It is a measure of the technology gap that an American engine almost 10 years old (first flown in 1955) was worth reverse engineering. The original AL-21F wasn't very successful, but was developed into the AL-21F-3 which as classified secret and rarely exported- perhaps to hide the ancestry of the Russian's most advanced turbojet of the time.
http://forum.keypublishing.com/showthread.php?113202-J79-versus-AL-21
I was under the impression the AL-21 was based on the J79 engine, specifically it copied the variable stator design. Looking at the specs, the AL-21 seems to be a physical copy as well.
According to Wikipedia their dimensions and weight were practically identical. However AL-21 delivers far more thrust. 6.6:1 compared to the J79's 4.6:1. The performance puts it in almost a different generation. What advancements does the Soviet engine have to account for this?
J79-GE-17
Length: 17.4 ft (5.3 m)
Diameter: 3.2 ft (1.0 m)
Dry weight: 3,850 lb (1,750 kg)
11,905 lbf (52.9 kN) dry vs 76.4 kN (17,175 lbf) dry
17,835 lbf (79.3 kN) with afterburner vs 109.8 kN (24,675 lbf) with afterburner
Thrust-to-weight ratio: 4.6:1 (45.4 N/kg) vs Thrust-to-weight ratio: 64.7 N/kg (6.6:1)
AL-21F3
Length: 5,300 mm (209 in)
Diameter: 1,000 mm (39 in)
Dry weight: 1,700 kg (3,740 lb)
76.4 kN (17,175 lbf) dry
109.8 kN (24,675 lbf) with afterburner
Thrust-to-weight ratio: 64.7 N/kg (6.6:1)
J-79-8 configuration: 17 stage compressor, 3 stage turbine
AL-21F-3A configuration: 14 stage compressor, 3 stage turbine
J-79-8 length: 5.3m
AL-21F-3A length: 5.16m
J-79-8 compression ratio: 13:1
AL-21F-3A compression ratio: 14.55:1
J-79-8 Mass flow: 76.7kg/sec
AL-21F-3A Mass flow: 104kg/sec
J-79 turbine entry temperature: 954°C
AL-21F-3A turbine entry temperature: 1093°C
No great magic - it sucks in more air, compresses it more, and burns it hotter. AL-21F is a later design and superior in all respects. It used some technology from recovered J-79s, but it is certainly NOT the same design. Its compressor is much more advanced getting more compression from less stages.
http://rbth.com/defence/2015/04/20/the_su-24_attack_interceptor_jack_of_two_trades_master_of_both_45379.html
the aircraft received two AL-21F engines instead. These, some experts claim, were designed using a J79 engine taken from a U.S. fighter shot down in Vietnam.
Boeing B-29 Tail Turret
The B-29 tail gun unit used in many Russian bombers up to Tu-95 bear and Il-76 jet transport
 Most Tu-95 models have very accurate, very effective twin 23mm tail guns. And we approach from behind! |  Tu-95 Bear taken during a QRA sortie. This picture shows the tail gunner and the camera operator, who is photographing us. Tail guns are normally pointed upwards like this during intercepts to show no hostile intent on their part. |
Tupolev Tu-4 - Wikipedia, the free encyclopediaWikipediaThe U.S. twice refused to supply the Soviet Union with B-29s under Lend Lease. .....militera.lib.ru: a compilation of articles published in 1988–1990 (in Russian).
How Russians copied captured B-29 - Telegraph The Daily TelegraphJan 27, 2001 - FRESH details showing how Stalin's engineers stripped a B-29Superfortress bomber "rivet-by-rivet" and copied it to produce their own aircraft ...
Russians Show How B-29 Was Copied in 1940s - latimes Jan 26, 2001 - The Russian historians brought an original sketchbook of fine pencil drawings of circles, lines and measurements of the B-29 Superfortress.
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