Tupolev Tu-104
The Tupolev Tu-104 is a medium-range, narrow-body, twin turbojet-powered Soviet airliner. It was the second to enter regular service, after the British de Havilland Comet and was the only jetliner operating in the world from 1956 to 1958, when the British jetliner was grounded due to safety concerns.
In 1957, Czechoslovak Airlines – ČSA, became the first airline in the world to fly a route exclusively with jet airliners, using the Tu-104A variant between Prague and Moscow. In civilian service, the Tu-104 carried over 90 million passengers with Aeroflot, and a lesser number with ČSA, while it also was operated by the Soviet Air Force. Its successors included the Tu-124, Tu-134, and Tu-154.
Design and development
At the beginning of the 1950s, the Soviet Union's Aeroflot airline needed a modern airliner with better capacity and performance than the piston-engined aircraft then in operation. The design request was filled by the Tupolev OKB, which based their new airliner on its Tu-16 "Badger" strategic bomber. The wings, engines, and tail surfaces of the Tu-16 were retained with the airliner, but the new design adopted a wider, pressurised fuselage designed to accommodate 50 passengers. The prototype built in MMZ 'Opit' first flew on June 17, 1955, with Yu.L. Alasheyev at the controls. It was fitted with a drag parachute to shorten the landing distance by up to, since at the time, not many airports had sufficiently long runways. The first serial TU-104 took off on 5 November 1955.The Tu-104 was powered by two Mikulin AM-3 turbojets placed in the wing roots, like the Tu-16. The crew consisted of two pilots, a navigator, a flight engineer, and a radio operator. The airplane raised great curiosity by its lavish "Victorian" interior – so-called by some Western observers – due to the materials used: mahogany, copper, and lace.
Tu-104 pilots were trained on the Ilyushin Il-28 bomber, followed by mail flights on an unarmed Tu-16 bomber painted in Aeroflot colors, between Moscow and Sverdlovsk. Pilots with previous Tu-16 experience transitioned into the Tu-104 with relative ease. The Tu-104 was considered difficult to fly, as it was heavy on controls and quite fast on final approach, and at low speeds displayed a tendency to stall, a feature common with highly swept wings.
Experience with the Tu-104 led the Tupolev Design Bureau to develop the world's first turbofan series-built airliner, the Tupolev Tu-124, designed for local markets, and subsequently the Tu-134.
Operational history
On 15 September 1956, the Tu-104 began revenue service on Aeroflot's Moscow-Omsk-Irkutsk route, replacing the Ilyushin Il-14. The flight time was reduced from 13 hours and 50 minutes to 7 hours and 40 minutes, and the new jet dramatically increased the level of passenger comfort. By 1957, Aeroflot had placed the Tu-104 in service on routes from Vnukovo Airport in Moscow to London, Budapest, Copenhagen, Beijing, Brussels, Ottawa, Delhi, and Prague.In 1957, ČSA Czechoslovak Airlines became the only export customer for the Tu-104, placing the aircraft on routes to Moscow, Paris, and Brussels. ČSA bought six Tu-104As configured for 81 passengers. Three of these were subsequently written off.
In 1959, a Tu-104 was leased to Sir Henry Lunn Ltd. of London, who used the aircraft to transport holiday-makers to Russia with a 4.5-hour flight time.
Whilst the Tu-104 continued to be used by Aeroflot throughout the 1960s and 1970s, the safety record of the aircraft was poor in comparison to Western jetliners. The Tu-104 was unreliable, heavy, and very unstable with poor control response and an inclination to Dutch roll. Poor design aerodynamics of the wings resulted in a propensity to stall with little or no warning and a dangerous tendency to pitch up violently before stalling and entering an irrecoverable dive. Due to the fear of inadvertent stalls, aircrew flew approaches above the recommended approach speed, landing at, nearly faster. At least two accidents were attributed to the pitch-up phenomenon, prompting changes to the design of the aircraft and operating procedures, but the problem remained. Aeroflot retired the Tu-104 from civilian service in March 1979 following a fatal accident at Moscow, but several aircraft were transferred to the Soviet military, which used them as staff transports and to train cosmonauts in zero gravity. After a military Tu-104 crash in February 1981 killed 50 people, the type was permanently removed from service. The last flight of the Tu-104 was a ferry flight to Ulyanovsk Aircraft Museum on 11 November 1986.
Variants
Data from:- Tu-104 – The initial version seating 50 passengers, it used two Mikulin AM-3 turbojet engines, each with of thrust; 29 airframes were built.
- Tu-104 2NK-8 – Proposed version, it was to be powered by two Kuznetsov NK-8 turbofan engines.
- Tu-104A – An improved version appearing in June 1957, its continued improvements of the Mikulin engines permitted significant growth in capacity, resulting in a 70-seater variant. The Tu-104A became the definitive production variant. On 6 September 1957, it flew with 20 t of payload at above mean sea level. On 24 September 1957, it reached average speed with a 2-tonne payload. In total, 80 airframes were built, of which six were exported to Czechoslovakia.
- Tu-104AK – A testbed aircraft, it was used for zero-g cosmonauts' training and testing the Soviet space program equipment.
- Tu-104A-TS – Five Tu-104As converted to freighter/medevac aircraft.
- Tu-104B – Further improvements were made by stretching the fuselage and fitting new Mikulin AM-3M-500 turbojets engines. The Tu-104B was able to accommodate 100 passengers. This variant took advantage of the newer fuselage from the Tu-110 and the existing wings. It began revenue service with Aeroflot on 15 April 1959 on the Moscow-Saint Petersburg route; 95 airframes were built. Most were later rebuilt to Tu-104V-115 standard.
- Tu-104B-TS – Six Tu-104Bs converted to freighter/medevac aircraft.
- Tu-104 CSA - Six aircraft built for CSA.
- Tu-104D – This VIP version had two sleeper cabins forward and a 39-seat cabin aft.
- Tu-104D-85 – Tu-104A airframes rebuilt to accommodate 85 passengers.
- Tu-104D 3NK-8 – Project powered by three NK-8 engines, precursor of Tu-154.
- Tu-104E – A higher performance Tu-104 powered by RD-16-15 engines, giving better fuel economy and greater thrust. Two prototypes were converted from Tu-104Bs СССР-42441 and СССР-42443. The program was cancelled in the mid-1960s in favor of the Tu-154.
- Tu-104G – This VIP version was for the federal government, with two VIP cabins forward and a 54-seat cabin aft.
- Tu-104LL – Several serial numbers were converted for use in testing Tu-129 and Tu-22M electronics, and air-to-air missile systems.
- Tu-104Sh – Navigator trainer in two versions.
- Tu-104V – The first use of this designation was for a projected 117-seat, medium-haul version with six-abreast seating; project cancelled.
- Tu-104V – The second use of this designation was used for Tu-104A airframes rebuilt to accommodate 100 or 105 passengers. A later version packed 115 passengers in by reducing seat pitch and adding seat rows.
- Tu-104V-115 – Tu-104B airframes were rebuilt to accommodate 115 passengers, with new radio and navigational equipment.
- Tu-107 – Prototype military transport version, with a rear loading ramp and a defensive turret armed with paired cannon. Although one aircraft was built, no production followed.
- Tu-110 – A four-engined version intended for export. A number of prototypes were built before the project was cancelled.
- Tu-118 – A projected turboprop freighter version powered by four Kuznetsov TV-2F engines.
Former operators
- CSA Czechoslovak Airlines – six aircraft
- Czechoslovak Air Force
- Military of Mongolia
- Aeroflot
- Soviet Air Force
Accidents and incidents
1950s
;19 February 1958;15 August 1958
;17 October 1958
1960s
;20 October 1960;1 February 1961
;16 March 1961
;10 July 1961
;17 September 1961
;2 November 1961
;4 June 1962
;30 June 1962
;3 September 1962
;25 October 1962
;18 May 1963
;13 July 1963
;16 August 1963
;9 June 1964
;28 April 1969
1970s
;1 June 1970;25 July 1971
;10 October 1971
;19 March 1972
;24 April 1973
;18 May 1973
File:Tu-104 Crash site near Nicosia airport.jpg|thumb|Wreckage of the Czechoslovak Airlines Tupolev Tu-104 near Nicosia airport
;29 August 1973
;30 September 1973
;13 October 1973
;7 December 1973
;5 November 1974
;30 August 1975
;9 February 1976
;17 July 1976
;28 November 1976
;1976
;13 January 1977
;17 March 1979