Paul Duffy/MOSCOW
It is almost a quarter of a century since the Ilyushin Il-76 freighter (NATO codename Candid) made its first appearance in the West at the 1971 Paris air show. Although a continuing review of the programme has resulted in many detail changes since then, few of these are evident to even a thorough observer.
Now, the first of a noticeably different new generation of Il-76s, the MF/TF, has been rolled out after some 850 aircraft in the original M (military) and T (airline) - and longer-range MD and TD - versions had been assembled at the Chkalov Aircraft Production Organisation in Tashkent, Uzbekistan.
The obvious differences are a fuselage stretch of 6.6m, and new Aviadvigatel PS-90A-76 high-bypass-ratio turbofans, which replace the D-30KPs on the earlier aircraft. The existing Il-76 barely meets Stage 2 noise limits with the earlier engines.
The Il-76 was designed originally to meet a Soviet air force requirement for a tactical transport capable of lifting 30-35t of vehicles and equipment, even from unprepared airstrips, and carrying its cargo some 3,000km (1,600nm). The first Il-76Ms entered service in 1974, giving the air force a capability, which matched that of the Lockheed C-141 StarLifter in US Air Force service. Soon Aeroflot was showing an interest and, in 1977, the first Il-76T civilian version entered commercial service.
Chief designer of the Il-76, Radii Papkovski, outlines the original air force requirement as encompassing:
multi-purpose use; the aircraft had to be able to carry everything from troops and tanks to buses and medical evacuees;
a capability for independent operation from remote, rough, airstrips with little ground support, which meant that it had to have its own loading/unloading equipment and ramps;
low operating costs and service simplicity. In the days of the Soviet Union, when the Government paid all wages and provided fuel free of charge, this concept was understood differently than in the West;
long range with large payload;
a capability to operate in all weather conditions and in extreme climates;
toughness and dependability for operation in hostile conditions.
The Il-76 met these requirements, and met them well. On one occasion during the Afghan conflict, an Il-76M was struck by a missile while cruising at 24,600ft (7,500m). A hole, 2.5 x 2m was blown in the fuselage, but the flight continued and the aircraft was landed safely at its destination, more than 200km away.
MODIFICATION MADE EASY
Modifying a proven military freighter for civilian use was easier in the Soviet Union than it might have been in the West. It involved removing most of the military equipment - which improved payload - and providing additional systems-redundancy. With the Soviet Government as the main customer for both models, there were few problems. The only major production change came at the beginning of the 1980s, when the longer-range MD (D for Dalnii or "far") was introduced, with the commercial TD following in 1982. By the time of the Soviet Union's collapse, Ilyushin had established a firm foothold for the Il-76 on the world air-cargo market.
The Il-76 offered ease of loading for large cargoes, and a reasonable range, combined with acceptable prices. Its lack of Western certification meant that few Western airlines could operate it, but operators in the former Soviet Union could benefit from providing worldwide charter services.
With the collapse of the Soviet Union came financial changes and pressures on all air operators - civil and military. Thus, the air forces of the CIS republics began to sell off Il-76s, mainly older aircraft. Ilyushin and the Il-76 repair factory at Bykovo, near Moscow, developed a "civilianisation" programme in conjunction with a major maintenance inspection, and the numbers of Il-76s in commercial service began to grow.
"Increased numbers of old aircraft in commercial service brought their own problems," says Papkovski; "They need more attention in service and are more costly to maintain, and this maintenance is usually heavily labour-intensive."
The International Civil Aviation Organisation (ICAO), meanwhile, has been growing more ecology-conscious, and noise, plus exhaust emissions, have become obstacles for older jet-powered aircraft. Soon the Il-76 will no longer be welcome at many of the world's airports. So Aeroflot's Central department of international air services, TsUMVS, now Aeroflot - Russian International Airlines and an operator of 19 Il-76s, approached Ilyushin and asked it to modernise its fleet.
Genrikeh Novozhilov, Ilyushin general designer, agreed, and a team was set up under chief designers Papkovski and Nikolai Talikov to carry out a study and perform the work. In August 1993, the TsUMVS flew an Il-76TD the short distance from Sheremetyevo to Ilyushin's base at Khodinka, Moscow's central airport, and work began.
FUNDS RAN OUT
"We started with enthusiasm," says Talikov. "At last, we were starting a worthwhile update of one of our best programmes. We knew we could deal with many of the Il-76 shortcomings. The PS-90A engine was becoming available, and would give more power and lower fuel consumption, as well as meeting the latest ICAO noise and emission standards.
"A modern cockpit would ease workload and could reduce flight crew, and we could make a variety of other improvements which would make the Il-76MF, as it was to be called, suitable for 1990s' needs," he says. So, what went wrong?
"Aviadvigatel increased the price of the PS-90A from 67 million roubles [in mid-1993 approximately $60,000] to 2,800 million roubles [by late 1994 close to $800,000]. The customer said 'no', and funds stopped. It cost too much for a rebuilt Il-76," says Talikov.
A few years earlier, some Western airlines had outlined to Ilyushin what they would like to see in an Il-76. The manufacturer had also led the drive for Western certification of Soviet/CIS aircraft with its Il-96M and Il-103. "We dusted off the plans and updated them. We were fortunate to find a strong interest in the stretched Il-76 from the [Russian] air force, and the air force agreed to help fund it and to flight test it free of charge to us.
"Then we reached agreement that the GosNII-GA, the civil-aviation test body, could participate in the flight trials and thus avoid a second costly programme," Talikov says. Ilyushin, in partnership with the Tashkent production factory and the Bykovo maintenance plant, managed to finance a civilian version without Government funding. "It was difficult, and we would still like to find backers - either investors or airline deposits - but we have almost completed it," he says.
The new aircraft includes a 6.6m stretch, achieved by inserting two 3.3m plugs into a standard Il-76 fuselage. Ilyushin had previously used this method to stretch the Il-96-300 to produce the Il-96M, and Lockheed had similarly stretched the C-141A into the C-141B, although it did not re-engine the StarLifter. The cargo compartment is almost 30% larger than that of the older TD, and payload has increased by a minimum of 4t, to 52t, which can be carried 4,500km with a 1h reserve at Mach 0.72. This represents a 28% improvement in tonne-kilometre performance over the TD, which can carry a 48t payload a distance of 3,800km for the same fuel consumption.
Design of the commercial Il-76TF presented the opportunity to omit from the outset all military equipment, and:
to design a new floor which will simplify cargo loading;
to install a new auxiliary-power unit and a digital system and engine monitor linked to a central computer;
to give the new Il-76 a much greater adaptability for a range of cargoes;
to aim for full Western certification;
to redesign the cockpit instrumentation. This allowed the cockpit crew to be reduced from five to four, by sharing the radio-operator's controls between the pilot, co-pilot and engineer. The fourth crewmember is the navigator. The first stretched Il-76 is a MF military version, but the civil TF model will not be far behind. Ilyushin is studying the market and listening to customer requirements.
"We are conscious of the bad press received by the PS-90A, and we have maintained close contacts with the designers and manufacturers in their efforts to solve the problems. They have developed a [rectification] programme and are working to find answers; and, of course, their Pratt & Whitney partnership will soon give us the PS-90P [designed] to Western certification standards. We have told them that we must have a more dependable engine with a longer service life," Talikov says, "but the PS-90 isn't our only option; we expect to offer the [General Electric/Snecma] CFM56-5 as an alternative."
CERTIFICATION GOALS
"The MF will be certificated initially to NLGS-2 standards - the Soviet military norms - but the joint military and civil test teams will greatly speed up civil certification. We are working to achieve Western certification also. We've learned some things from the West - the Il-76MF will receive credit as appropriate from the service of the MD and TD, and we expect to achieve certification in six months to a year," Talikov explains.
Ilyushin has received unspecified military orders for the Il-76MF, but none has yet been logged for the civil TF. The manufacturer is optimistic, however. "The new TF has a number of advantages," says Talikov, citing:
there are few jet freighters purpose-built to meet industry needs;
the aircraft will meet ICAO Stage 3 noise requirements and ecological standards, and thus can operate into any airport of reasonable size;
the operating costs, including fuel, crew and maintenance, will be lower than for current aircraft.
Ilyushin says that the Il-76TF will give cargo airlines the ability to continue operating worldwide and at lower tonne-kilometre costs, which should mean higher profitability. An airline planning to stay in the large cargo market should find the TF of interest, the manufacturer argues.
Source: Flight International
