Update – Tupolev Bravia Tu-204

ability of worldwide product support as other key advantages. Tupolev does not rule out the possibility of Rolls-Royce powered Tu-204s being used in Russia, but the 535E4 also offers major advantages for other operators. There is a need to replace a fleet of about 700 aircraft of this size over the coming decade for domestic operations alone.

Tu-204 Design

Tupolev have designed and developed five different types of jet airliner before the Tu-204; the Tu-104, Tu-124, Tu-134, these aircraft have been produced and 1300 remain in the supersonic Tu-144 and the trijet Tu-154. Over 3000 of ice today, including more than 300 with 15 carriers in Discussions with Rolls-Royce began in 1988 and a proto-Tu-204 is thus based on extensive experience. col between Tupolev and Rolls-Royce was signed in 1989. This covered a design study to assess the potential for installing the RB211-535E4-B engine on the aircraft.

tries outside the Russian Federation. The design of the The design bureau is located in Moscow and the flight The 535E4 powered Tu-204 made a 60 minute first flight at Zhukovsky near Moscow on August 14 1992, just two weeks after its rollout. It was also one of the star attractions at Farnborough ’92, where interest in the type led to the announcement of a freighter version. Since then flight development has been demonstrated to potential customers, in particular during January 1993 when it was used to carry a high level Russian delegation on a visit to India.

Russian certification of the Tu-204 with Perm PS-90A engines has already been achieved, with certification of the 535E4 powered version expected in late 1994. There are parallel production lines planned for Tu-204s with Russian and RR engines while a number of production slots for 535E4 powered aircraft have been allocated for, 1995 and 1996.

The aircraft is designed to carry 178 to 214 passengers, depending on the seating configuration, over distances up to 3000nm. The Tu-204’s passenger cabin is slightly shorter than that of the Boeing 757, but it has a longer span wing with optimised aerodynamics and winglets. It also makes greater use of composite materials in its wing and tail. Its fin incorporates a fuel trim tank which assists in trimming the aircraft to reduce its overall drag.

The initial version of the Tu-204 for Aeroflot is powered by Perm PS-90s rated at 35,000lb takeoff thrust at sea level. This compares with 43,000lb for the Rolls-Royce RB211- 535E4-B. Full thrust is not normally used by the Rolls Royce powered Tu-204, which has a detent to prevent throttle movement above the point where the engines provide the maximum thrust of two PS-90s. Additional thrust up to the full E4-B rating can be provided if needed by further movement of the throttles, and this extra power will be valuable for future stretch and higher mass versions of the Tu-204. The full E4-B thrust rating will be certificated for the higher gross mass (3500nm) version designated the Tu-204-200.

The PS-90 is a new Russian engine designed specifically for the Tu-204 and selected for a number of new designs, but it is not yet backed by the extensive operating experience accumulated by the 535E4. According to the Tupolev design bureau, the advantages of installing the 535E4 engine lie in its maintainability and reliability – characteristics vital to the performance of a twin engined aircraft. The bureau cites the operating life of the 535E4 and the availtest centre is situated at Zhukovsky, which is also the site of the Russian Central Aerodynamics Institute. The Tu-204 is manufactured by the recently privatised company Aviastar, which employs 36,000 people at Ulyanovsk, 800 kilometres south of Moscow.

The Tu-204 has been designed from the outset for two pilot operation, low noise levels and good maintainability. It incorporates advanced aerodynamics, structures, materials and avionics. The avionics include a Russian made glass cockpit with colour cathode ray tube displays. It has a digital fly-by-wire control system with analog backup. In order to meet customer requirements for the 535E4 powered aircraft, Western avionics from Collins are also being in- stalled. The aircraft’s flight management system provides the capability for automatic flight from takeoff to landing under ICAO Category III conditions.

The Tu-204 is being certificated to meet Russian and European Joint Aviation Authority (JAA) requirements. Cross validation is also being discussed with the US Federal Aviation Administration (FAA).

Advanced Turbofan Engine

In selecting the 535E4 engine for the Tu-204, Tupolev and Aviastar have opted for the advanced turbofan chosen by over three quarters of Boeing 757 operators. Its reliability has been proved in more than nine years of service and it has demonstrated very low ownership costs. The 535E4 engine has now accumulated nearly six million hours of operating experience since it entered service a decade ago.

The triple shaft 535E4 incorporates features of earlier RB211s which provide very low performance deterioration, while also introducing technology advances such as the wide chord fan, the use of Kevlar for fan blade retention, computer aided three dimensional turbine design and an integrated exhaust nozzle. This engine has also achieved impressive reliability in high intensity service since its introduction. For example, a 535E4 remained on the wing of an Air 2000 Boeing 757 which it powered for 19,157 flight hours. When overhauled, it was evident that the engine could have remained in service for more than 20,000 hours. Reliability is vital for a charter operator whose airliners fly from 4000 to 4500 hours a year, including up to 18 hours a day during its intensive summertime operations.

The 535E4 engine was also the first to enter service with Rolls-Royce wide chord fan blades, later introduced for a range of other Rolls-Royce engines. This type of fan blade, a which is wider and stiffer than other blades, does not require part chord snubber to stabilise it. As a result, it provides a more efficient aerofoil which reduces fuel consumption.

The blade is also more robust, improving resistance to damage caused by the ingestion of large birds and other foreign objects. This provides excellent integrity. No Rolls- Royce wide chord fan blade has failed in service – even though one engine ingested at least three Canada Geese each weighing around four kilograms.

The repair shop visit rate for 535E4 engines has been well under 0. 1 visits per 1000 flying hours for over three years. In 1992 the total inflight shutdown rate for the engine aver- aged well under 0. 01 shutdowns per 1000 hours – equivalent to one shutdown in more than 100,000 engine hours. This reliability contributed to the 180 minute clearance of the 535E4 engine for extended twinjet operations (ETOPS) in Boeing 757s. Since July 1990, Boeing 757s equipped with this engine have been cleared by the FAA to operate at up to 180 minutes of single engine flight time from alternate airfields. This means that the aircraft can operate on direct nonstop flights over most oceans and remote parts of the world. ETOPS clearances are granted progressively and are based on accumulated operating experience; the previous ETOPS clearance for the 535E4 permitted 757s equipped with the RR engine to operate up to 120 minutes of single engine flight time from the nearest usable airfield.

ETOPS clearance will be very valuable to Tu-204 operators that want to operate long distance overwater non stop services. This provides flexibility of operation and savings in fuel and flight time. Rolls-Royce 535E4 engines have so far been used on ETOPS flights by 20 operators around the world, and over 150,000 hours of revenue ETOPS flying have been accumulated with them. At time of writing there have been no inflight shutdowns with the engines during ETOPS flights.

Another benefit of the 535E4 is its low noise level, a key requirement for operation from airports with strict noise limits and nighttime curfews. The Boeing 757 with 535E4 engines, for example, is the only version of the 757 allowed to operate between 2200 and 0700 hours at Washington National Airport.

Finance, Marketing and Support

In 1991 Rolls-Royce sought ways of financing the programme for the 535E4 powered Tu-204. Discussions with Moscow Narodney Bank, the London merchant bank Robert Fleming & Company and Russian partners led to the formation in April 1992 of the British Russian Aviation Cor- poration (Bravia). This is a Russian joint stock company with shareholdings by the Tupolev design bureau, Aviastar and a Fleming subsidiary, the Fleming Russia Investment Corporation, which is also engaged in other aviation related activities.

The aim was to create a business structure which would enable the Rolls-Royce powered Tu-204 to be professionally marketed and fully supported in operation while meeting the requirements of all parties involved. This is being achieved by Bravia, which is responsible for coordinating the design, manufacture, certification, marketing and after sales support for the aircraft.

Bravia has directors from the three shareholder organisations plus one from Rolls-Royce. Each of the four organisations is entering supply agreements with Bravia covering design and certification (Tupolev); aircraft manufacture (Aviastar); finance (Fleming); and engine supply (RollsRoyce). In addition, Bravia is undertaking agreements with Western Suppliers covering avionics, interiors and aircraft customer support. Engine support will be provided by the worldwide Rolls-Royce service organisation and a contractor also is being sought to provide airframe support.

The Tu-204 will feature an all new interior that will cater for all the usual airline options and buyer furnished equipment. A 535E4 powered Tu-204 with an example of this western interior was displayed at last years Paris Salon.

The Tupolev/Bravia Tu-204 offers operators an advanced airliner design at an economic cost, equipped with proven and fuel efficient western engines, avionics and interior. While initial sales are expected to go to countries in and bordering the Commonwealth of Independent States, the Tu-204’s appeal to operators in other parts of the world is likely to grow as the type is proven in service.