A Sample Feature From Aviation News
Russian survivor Tupolevs 204
The Tu-204 was revolutionary when it was conceived, but unfortunately a potentially promising career with Aeroflot was overtaken by the profound changes that swept through the Soviet Union in the early 1990s. David Willis reviews the slow development of an airliner which could have matched some of the best designs produced in the West.
Above: The second flying Tupolev Tu-204 prototype, CCCP-64003, tucks up its undercarriage during a display at the 1991 Paris Air Show. (Photo, author).
Andrei Nikolayevich Tupolev is famous for the bombers that emerged from his OKB (opytno konstruktorskoye byuro, experimental construction bureau), but his airliners too have made their mark. The Tu-104, based on the Tu-16 bomber, pioneered jet airliner travel in the Soviet Union and led to the later scaled-down
Tu-124 which itself was later redesigned as the T-tailed Tu-134. The latter was superseded by the Tu-154, effectively a scaled-up tri-jet version of the earlier aircraft. Having spent much effort trying (and failing) to perfect the Tu-144 supersonic transport, the Tupolev OKB was determined to get it right when Aeroflot outlined a requirement for a Tu-154 and Ilyushin Il-62 replacement in 1982.
The future aircraft was destined to cover much in the way of new ground for Soviet airliner design. It was to have a longer life than contemporary types with up to 60,000 flight hours or 45,000 cycles over a 20-year period. The layout adopted was a break from that used by previous generations of Tupolev airliners where the engines had either been buried in the wings or mounted on the rear fuselage, while extensive use was to be made of composite materials in its construction. Western airliner manufacturers especially Airbus had learnt from the evolution in information technology that was occurring in the 1980s and applied it to airliners by introducing fly-by-wire technology and electronic flight information systems. Both of these technologies were incorporated in the new airliner. Power was to come from a pair of Aviadvigatel (later Perm) PS-90 turbofans, the first (and only) fourth generation commercial engine produced in the Soviet Union with greater fuel efficiency than existing Soviet powerplants. As the new airliner would be a fresh start it was appropriate that it left the 100-series of number designations behind and became known as the Tu-204.
Above: Only a few months after its initial flight on January 2, 1989, the prototype Tu-204 made its western debut at that years Paris Show. It is seen here parked between the first Ilyushin Il-96 behind and a two-seat MiG-29 on the left. (Photo, Av News).
The design team, led by Lev Aronovich Lanovskii, finalised the Tu-204s general layout in 1986. Aeroflot announced it had a requirement for 500 aircraft and ordered an initial 350 in 1988. Andrey I Talalakin occupied the pilots seat for the first flight of the prototype on January 2, 1989. Three more flying prototypes were produced, along with static and fatigue test airframes (the second and fifth airframes produced). All except the last were powered by PS-90A engines, incorporating fan-duct blockers and all-round reverser cascades to meet Aeroflots original requirement for the aircraft to be able to operate from the short, austere airfields in widespread use within the Soviet Union. Production of the Tu-204 began at the Aviastar facility at Ulyanovsk in 1990. The addition of a wing centre-section fuel tank to the pre-production Tu-204s resulted in the Tu-204-100, the starting point for the majority of the versions built or proposed. Cargo-carrying versions are denoted by the suffix C or S, the Cyrillic C being the equivalent of the S in the Roman alphabet.
The biggest change that was to affect the Tu-204 programme and the aerospace industry as a whole was the break-up of the Soviet Union. No longer was Aeroflot after 500 aircraft, in fact there was a surplus of airliners sitting idle at many airports as the once huge national airline splintered off into small off-shoots. This problem was compounded further by several other factors. The structure of the Soviet aviation industry meant that the aircraft designers in the OKBs were separate from the factories that built their products and these production centres had no experience of marketing the aircraft. After the break up of Aeroflot the prospect of mass-production for a single customer had been replaced by the need to chase many different customers, each for a much smaller number of orders. Most of the new Russian airlines were in a parlous financial state. It was only because the Tu-204 had been designed to a modern standard of efficiency that it had a chance of surviving in the market, because it was clear that as soon as the market recovered the new airlines would go shopping for the best deal, and although Soviet-era airliners were plentiful and cheap their operating costs were poor.
One logical solution presented itself. If the home market could not afford the Tu-204, then it would have to be marketed to overseas customers. One potential obstacle to sales outside the old Soviet Union was the reputation of Soviet-era powerplants that (in general) had a higher fuel-burn and a shorter time between overhaul than Western equivalents. The obvious answer, although revolutionary at the time, was to fit a Western engine to the Tu-204. The sixth airframe built and fourth flying prototype, was equipped with Rolls-Royce RB211-534E4-Bs and first flew on August 14, 1992, with Sergei Popov at the controls. The Rolls-Royce-powered version was designated the Tu-204-120 and was displayed in British Russian Aviation (Bravia) colours at the 1996 Farnborough airshow before receiving its Russian certificate in July 1997. The first production Dash 120 (RA-64027, later
SU-EAF) made its maiden flight on 6 March 1997. As well as Rolls-Royce engines western avionics from Honeywell, Litton, Rockwell Collins and Sextant Avionique were offered for the Tu-204, while United Interiors was approached to provide modern cabin designs in 1996.
Above: To gain greater acceptance in Western markets, the fourth airframe was given Rolls-Royce RB211 turbofans and embarked on a number of sales tours. The aircraft, RA-64006 in Bravia colours, is seen at the Singapore Show in 1996. Unfortunately, the conversion proved not to be as successful as had been hoped. (Photo, Av News).
While the Tu-204 has more than a passing visual resemblance to the rival Boeing 757 (and the unbuilt Hawker Siddeley HS.134) it differs in all respects from the American design. A narrowbody low-wing twinjet, the Tu-204 has a wing with 28º of sweep and winglets. Power is provided by a pair of Aviadvigatel PS-90A turbofans, each capable of producing 35,300 lb st (157kN). A 620 Imp gal (2820 litre) trim tank is located in the fin, while the majority of the 6,600 Imp gal (30,000 litre) fuel load is carried in the wings in integral fuel tanks. The wings have four-section hydraulic-powered leading-edge slats, two-section inboard double-slotted trailing edge flaps, two airbrake/lift dumpers and five spoilers each. The skin aft of the wing box and the large wing/body fairings are made from glassfibre honeycomb, while all the moveable surfaces are carbon-fibre composites, as is the tail leading-edge and the one-piece tailplane moveable surfaces. In total, 18% of the Tu-204 is constructed from composites. The main undercarriage bogie incorporates four tyres (107 x 39 cm), while the steerable nose gear has two smaller units (84 x 29 cm).
Where the Tu-204 differed from earlier Soviet airliners was in its use of a triplex digital fly-by-wire system, backed up by an analogue standby with a hydraulic pump powered by the auxiliary power unit (APU) to provide it with a pressure reservoir for use in emergencies. Cockpit avionics were arranged around six liquid crystal display screens for the presentation of flight, navigation and engine parameter information, while a conventional yoke was provided for both the pilot and co-pilot. A side-stick controller, as used on most Airbus aircraft, was investigated but rejected. Aeroflot-specified avionics for the Tu-204 included a triple inertial navigation system (INS), VOR/DME navigation aids and an instrument landing system to Category IIIA (blind landing) standards. It was to be flown by a crew of two (pilot and co-pilot), with provision for an engineer and an observer, the latter being an Aeroflot requirement.
A basic one-class seating arrangement can accommodate 214 passengers in a three-by-three layout, or more typically, 12 passengers in four-by-four seating plus 184 tourist seats.
The under-fuselage holds have a capacity of 932cuft (26.4m3), with the forward bay limited to 7,992 lb (3625kg) and the aft to 11,119lb (5075kg). A Stupino TA-12-60 APU is located in the rear fuselage tailcone to provide power for engine start, the environmental control system and emergency electricity.
Russian certification of the basic Tu-204 was awarded on 12 January 1995, allowing the aircraft to be used initially for freight-carrying operations, a standard introduction into service for Soviet airliners. Aeroflot Russian International Airlines was to receive four freighters and although tested by the airline from April 1995 they did not enter full service with the airline because of problems experienced with PS-90 reliability. During 1994 Vnukovo Airlines had undertaken trial flights with a Tu-204 provided by the Aviastar factory and later ordered four. The airline flew the first revenue-earning passenger flight on 23 February 1996, servicing the Moscow/Mineralnye Vody route. Vnukovo Airlines placed a second order for three in 2000, but unfortunately the operator suspended flights in 2001 when it was integrated with Sibir.
There have been several false promises for the Tu-204 programme, with orders being reported but failing to materialise. One of the early examples was Aviastar Asia, a joint venture with offices in Taipei, Taiwan, between Aviastar (25% stake) and several south-east Asian financial institutions launched on July 24, 1996. The consortium was set up to provide leasing, financial and technical support for 20 PS-90 and RB211-powered Tu-204s and Tu-234s and place them in service in the traditional Russian airliner markets Africa, Asia, the former Soviet states, Eastern Europe, the Middle East and the Pacific rim. Ordered in late-1996, the delivery of six was due to start in late-1997 with the final three due in 1999. The maintenance and overhaul centre at Kao-Hsing Airport in Taiwan was to be modernised to provide support for the Tu-204 and PS-90 powerplant, while a Moscow-based subsidiary, Aviastar Financial International, was also planned. However, the order was never placed.
A second international opportunity also occurred in 1996 when a deal with the Egyptian Kato Group was announced in August. This became an important lifeline for the Tu-204 and could not have come at a better time. By the end of 1996 Aviastar had only completed four Tu-204s, while a further 18 were in various stages of assembly when production ground to a halt. Aviastar was encountering economic difficulties and resorted to seeking guarantees from the Russian government to provide $30m to fund the completion of the additional aircraft.
Above: Vnukovo Airlines was established in March 1993 and the following year undertook some trial flights with the new Tupolev airliner. Four were ordered and the airline introduced the type into service in February 1996. (Photo, Av News).
For the rest of this feature please see the April 2006 issue.