Tu-154
November 5th, 2008
The Tu-154 was developed to meet the Aeroflot requirement for a new aircraft to replace the jet-powered Tu-104, plus the Antonov An-10 'Ukraine' and Ilyushin Il-18 turboprops. It competed against the Ilyushin Il-62. The Soviet Ministry of Aircraft Industry picked the Tu-154 because it incorporated the latest in Soviet aircraft design and best met Aeroflot's anticipated requirements of the 1970s and 1980s. The aircraft was to transport a payload of 16 to 18 tons (35,270 to 39,680 lb) over a distance of 2,850 - 4,000 km (1,770 - 2,480 mi) while cruising at a speed of 900 km/h, or a payload of 5.8 tons (12,790 lb) over a distance of 5,800 - 7,000 km (3,600 - 4,350 mi) while cruising at 850 km/h (528 mph). It also had to be able to operate from airfields as short as 2,600 m (8,530 ft) at maximum take-off weight
The first project chief was Sergey M. Yerger. In 1964 Dimitriy S. Markov assumed that position. In 1975 he turned it over to Aleksandr S. Shengardt.
The Tu-154 first flew on October 4, 1968. Commercial service began in February 1972, and production ended in 2006. About 900 Tu-154s have been built, 500 of which are still in service.
In 1988 a modified Tu-154 (dubbed Tu-155 and Tu-156) successfully flew on liquid hydrogen and in 1989 on liquified natural gas used as a fuel in its engines.
The Tu-154 is powered by three rear-mounted low-bypass turbofan engines arranged similarly to those of the Boeing 727, and is slightly larger than its American counterpart. The original model had Kuznetsov NK-8-2, while the Tu-154M has Soloviev D-30KU-154s. All Tu-154 aircraft models have a higher thrust-to-weight ratio than that of the 727 – this gives them superior performance, although at the expense of poorer fuel efficiency, which became an important factor in later decades as fuel costs grew.
The cabin of the Tu-154, although of the same six-abreast seating layout, gives the impression of an oval interior, with a lower ceiling than is common on western airliners (Boeing or Airbus). The passenger doors are also smaller than on the Tu-154's western counterparts. Furthermore, luggage space in the overhead compartments is very limited.
Like the Tupolev Tu-134, the Tu-154 has a wing swept back at 35 degrees at the quarter-chord line. The British Hawker Siddeley Trident has the same sweepback angle, while the Boeing 727 has a slightly smaller sweepback angle of 32 degrees.
Like many other Soviet-built airliners, the Tu-154 has an oversized landing gear enabling it to land on unpaved runways, once common in rural areas of the Soviet Union. The aircraft has two six-wheel main bogies fitted with large low-pressure tyres that retract into pods extending from the trailing edges of the wings (a common Tupolev feature), plus a two-wheel nose gear unit. Soft oleo struts (shock absorbers) provide much smoother ride on the bumpy airfields than Western airliners, which only very rarely operate on such poor surfaces.
The passenger cabin accommodates 128 passengers in two-class layout and 164 passengers in single-class layout, and up to 180 passengers in high-density layout. The layout can be modified to what is called a winterized version where some seats are taken out and a wardrobe is installed for passenger coats.
The original requirement was to have a 3 man flight crew - Captain, First Officer and Flight Engineer - as opposed to 4 or 5 man crew on other Soviet airliners. However, a fourth crew member, a navigator, is usually also present, at least in the former Soviet Union, due to the union rules. Navigators are no longer trained and this profession will become obsolete with the retirement of older Soviet planes.
The plane's avionics suite, for the first time in the Soviet Union, is built to Western airworthiness standards. It includes an NVU-B3 doppler navigation system, a triple autopilot, which provides an automatic ILS approach according to ICAO category II weather minima, an autothrottle, a Doppler drift and speed measure system (DISS), "Kurs-MP" radio navigation suite and others. Modern upgrades normally include a TCAS, GPS and other modern systems, mostly Western-made.
The earlier versions of Tu-154 cannot be modified to meet the current Stage III noise regulations, and therefore are banned to fly in Europe and other regions, where such regulations are in force. The Tu-154M, however, can be hush-kitted to meet the Stage III regulations. Theoretically, it can be hush-kitted to meet the formal Stage IV noise regulations. However, the current European Union directives prohibit to hush kit aircraft to meet Stage IV noise levels. Unless the TU-154M is re-engined, which will require extensive modifications that can be astronomically expensive, it is unlikely that Tu-154 will continue operating in the EU with Stage IV regulations in force.
There have been 62 serious flight incidents with TU-154s, including 36 crashes with human fatalities. Six of those incidents have resulted from terrorist or military action and several from poor runway conditions, including one which struck snow ploughs left on the runway. Others incidents have resulted from mechanical problems, piloting errors, cargo fires, and faulty air traffic control. After the TU-154 had been in service for 26 years and logged some 21 million flight hours (1998), it had a better than average safety record measured as 1.7 times fewer incidents than the world ICAO average at that time.
The TU-154 can easily be called a Russian legend.
