Tupolev Tu-104B

The Tu-104B was the third and last of the official modifications of the first Soviet jet airliner, following the initial 50-seat Tu-104 and the 70-seat Tu-104A. It was born in 1958, when the four-engined Tu-110 failed to go into production: instead, the Tupolev bureau combined the Tu-110's longer fuselage with the existing Tu-104 wing. The result had a fuselage stretched by about 1.2 m (1.21 m according to aviastar and all-aero), a galley in the forward part of the cabin and room for 100 passengers; aerospaceweb gives the split as 30 seats in the forward cabin, 15 above the wing spars and the remainder in the aft cabin. Most aircraft were later rebuilt to carry 115 passengers with new radio and navigation equipment, giving rise to the Tu-104B-115 variant.

The stretch was made possible by continuing development of the Mikulin engine. The Tu-104B was powered by two RD-3M-500 turbojets, a designation that the English Wikipedia and aviastar give as AM-3M-500. Sources disagree on thrust: airwar.ru gives 9,500 kgf per engine, while the English Wikipedia states 9,700 kgf (about 95,000 N) and aviastar 95.1 kN. To keep the heavier aircraft's take-off and landing performance at the level of the Tu-104, airwar.ru says flaps of increased area were fitted, as on the Tu-110; the Russian Wikipedia's table of modifications, however, describes the wing high-lift devices as unchanged.

According to airwar.ru the first flight took place in 1958; none of the sources consulted gives the exact day. The first test flights, at the civil aviation research institute GosNII GVF with pilot K. Sapelkin, revealed shortcomings: reverse roll response to rudder input, reduced longitudinal and directional stability margins, and buffeting and wing drop at Mach 0.82.

Production was concentrated at Plant No. 22 in Kazan, which built 96 aircraft of the family in series 1 to 20 between 1958 and 1960, all of them Tu-104Bs except the third and fifth aircraft of series 9, completed as Tu-104Es. The English and Russian Wikipedias put the number of Tu-104Bs built at 95. The Tu-104B began revenue service with Aeroflot on 15 April 1959 on the Moscow-Leningrad route, and the airwar.ru data sheet gives it an empty weight of 44,020 kg, a maximum take-off weight of 78,100 kg, a cruising speed of 800 km/h, a service ceiling of 12,000 m and a payload of 100 passengers or 12,000 kg of cargo, with a crew of five.

A year after it appeared, the Tu-104B was also used for records: according to airwar.ru, on 1 August pilot Kovalev flew 1000 km with a 15 t payload at an average speed of 1015.86 km/h, and on 4 August the crew of Alasheev lifted 25 t to 12,799 m. Meanwhile, in 1958 the Council of Ministers had ordered Plant No. 22 to build five Tu-104V aircraft in a 116-seat tourist layout, but a series of Tu-104 accidents led to that work being dropped.

The Tu-104B's service life was marked by numerous accidents. Among the worst were Flight 1912 at Irkutsk on 25 July 1971, the bombing of Flight 773 on 10 October 1971, Flight 3932 after take-off from Koltsovo on 30 September 1973, with 108 killed, and Flight 964 near Domodedovo on 13 October 1973, with 122 killed, the deadliest accident of the whole type. On 17 March 1979 Flight 1691 crashed while trying to return to Moscow after a false fire alarm, and after that accident Aeroflot retired the Tu-104.

According to Ministry of Civil Aviation documents cited by the Russian Wikipedia, the last scheduled Moscow-Odessa service by a Tu-104 was flown by a 100-seat Tu-104B on 5 November 1979, and operation of the type ended on 31 December 1979 with Flight 2429, a 115-seat Tu-104B from Sheremetyevo to Pulkovo. Some aircraft had a second life: СССР-06195 served as the design bureau's liaison aircraft and then as a flying laboratory for the Tu-144 navigation system, passing to the LII institute in 1974; СССР-42498 went to NPO Vzlyot in 1974 to test the MiG-31's radar and missile guidance system, earning the nickname "Buratino" for its distinctive nose. Tu-104Bs СССР-42441 and СССР-42443 became the two Tu-104E prototypes, and six aircraft were converted into Tu-104B-TS medical transports.