Tupolev 95 (Bear)
The Tupolev Tu-95 (Russian: Туполев Ту–95; NATO reporting name: Bear) is a large, four-engine turboprop-powered strategic bomber and missile platform. First flown in 1952, the Tu-95 entered service with the Soviet Union in 1956 and is expected to serve the Russian Air Force until at least 2040. A naval development of the bomber is designated Tu-142.
The aircraft has four Kuznetsov NK-12 engines, developed by the Kuznetsov Design Bureau with participation of Ferdinand Brandner and other captured German engineers, each driving contra-rotating propellers. An airliner variant Tu-114 holds the record as the world's fastest propeller-driven aircraft. Some experimental aircraft were designed for theoretically higher speeds, but none attained or registered them. It also remains the only turboprop-powered strategic bomber in operational use. Its distinctively swept-back wings are at 35°, a very sharp angle by the standards of propeller-driven aircraft, and justified by its operating speeds and altitudes. Its blades, which rotate faster than the speed of sound, according to one media source, make it arguably the noisiest military aircraft on earth, with only the experimental 1950s era Republic XF-84H "Thunderscreech" turboprop powered American fighter design as a likely rival.
The design bureau led by Andrei Tupolev designed the Soviet Union's first intercontinental bomber, the 1949 Tu-85, a scaled up version of the Tu-4, a Boeing B-29 Superfortress copy. The Tu-4 was deemed to be inadequate against the new generation of American all-weather interceptors.
A new requirement was issued to both Tupolev and Myasishchev design bureaus in 1950: the proposed bomber had to have an un-refueled range of 8000 km (4,970 mi) — far enough to threaten key targets in the United States. Other goals included the ability to carry an 11,000 kg (11 ton) load over the target.
The big problem for Tupolev was the engine choice: the Tu-4 showed that piston engines were not powerful enough to fulfill that role, while the fuel-hungry AM-3 jet engines of the proposed T-4 intercontinental jet bomber did not provide adequate range.Turboprops offered more power than piston engines and better range than jets, with a top speed in between.
Tupolev's proposal was selected and Tu-95 development was officially approved by the government on 11 July 1951. It featured four Kuznetsov] coupled turboprops fitted with eight-bladed contra-rotating propellers, producing a nominal 8,948 kW (12,000 eshp) power rating. Unlike the advanced engine design, the fuselage was conventional: a mid-wing cantilever monoplane with 35 degrees of sweep, an angle which ensured the main wing spar passed through the fuselage in front of the bomb bay. Retractable tricycle landing gear was fitted, with all three gear strut units retracting rearwards, with the main gear units retracting rearwards into extensions of the inner engine nacelles.
The Tu-95/I, with 2TV-2F engines, first flew 11 November 1952 with test pilot Alexey Perelet at the controls.After six months of test flights this aircraft suffered a propeller gearbox failure and crashed, killing Perelet. The second aircraft, Tu-95/II featured four of the 12,000 ehp Kuznetsov NK-12 turboprops which proved more reliable than the coupled 2TV-2F. After a successful flight testing phase, series production of the Tu-95 started in January 1956.
Initially the United States Department of Defense evaluated the Tu-95 as having a maximum speed of 644 km/h (400 mph) with a range of 12,500 km (7,800 mi). These numbers had to be revised upward numerous times.For a long time, the Tu-95 was known to U.S./NATO intelligence as the Tu-20. While this was the original Soviet Air Force designation for the aircraft, by the time it was being supplied to operational units it was already better known under the Tu-95 designation used internally by Tupolev, and the Tu-20 designation quickly fell out of use in the USSR. Since the Tu-20 designation was used on many documents acquired by U.S. intelligence agents, the name continued to be used outside the Soviet Union.
Like its American counterpart, the Boeing B-52 Stratofortress, the Tu-95 has continued to operate in the Russian Air Force while several subsequent iterations of bomber design have come and gone. Part of the reason for this longevity was its suitability, like the B-52, for modification to different missions. Whereas the Tu-95 was originally intended to drop free-falling nuclear weapons, it was subsequently modified to perform a wide range of roles, such as the deployment of cruise missiles, maritime patrol (Tu-142), and even civilian airliner (Tu-114). An AWACS platform (Tu-126) was developed from the Tu-114. An icon of the Cold War, the Tu-95 has served not only as a weapons platform but as a symbol of Soviet and later Russian national prestige.
General characteristics
- Crew: 6–7
- Length: 46.2 m (151 ft 6 in)
- Wingspan: 50.10 m(164 ft 5 in)
- Height: 12.12 m (39 ft 9 in)
- Wing area: 310 m² (3,330 ft²)
- Empty weight: 90,000 kg (198,000 lb)
- Loaded weight: 171,000 kg (376,200 lb)
- Max. takeoff weight: 188,000 kg (414,500 lb)
- Powerplant: 4 × Kuznetsov NK-12M turboprops, 11,000 kW (14,800 shp) each
Performance
- Maximum speed: 920 km/h (510 knots, 575 mph)
- Range: 15,000 km (8,100 nmi, 9,400 mi) unrefueled
- Service ceiling: 13,716 m (45,000 ft)
- Rate of climb: 10 m/s (2,000 ft/min)
- Wing loading: 606 kg/m² (124 lb/ft²)
- Power/mass: 235 W/kg (0.143 hp/lb)
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