Tu-154 by S.Yeger (Tupolev OKB)
(NATO "Careless")

Tu-154 is the first Soviet aircraft since the 1930s developed under pressure of the economical factors. The early 60's were marked by rapid expansion of aerial transportation in the USSR and simultaneous growth of competition on the international market. The medium-range routes were dominated by three types: An-10, Il-18 and Tu-104. There were no need for three different types operated by single state-controlled company (Aeroflot), while operation and financial penalties became obvious.

Most of the best features were combined in the new set of the MGA requirements:

• 150 to 160 passengers
• comfort of the Tu-104
• accommodation of Tu-104 services and repair base
• range 3,200 to 3,500km
• maximum runway demand 2,500m
• cruising speed 950km/h
• capable of operation from second class fields

After examining the submissions from O.K.Antonov, S.V.Ilyushin and A.N.Tupolev, the MGA chose Tupolev's design proposal.

To satisfy MGA demands, S.Yeger (who was chosen by Tupolev to lead the project) had to develope a entirely new wing and provide much more engine power than was common at the time. Choice of three NK-8-2 engines also allowed to keep engine wear and fuel consumption down compared with aircraft already in service. New design inherited Tupolev's distinctive trailing edge fairings for the main landing gear, as well as general outline features of the Tu-134, but inside it was entirely different plane.

• Multiple systems redundancy - most important system had 3 parallel independent circuits.
• Control boosters on all surfaces (also multiple redundancy). Even with all engines down, the incoming airflow provided enough power to operate boosters.
• Extensive wing mechanization: slats, triple-slotted flaps, spoilers
• New six-wheel three-axle main undercarriage boogie produce less stress on the runway than other aircraft of same class

There even was a joke that Tu-154 has three where Tu-134 has two (wing spars, main wheels etc). Outer engines are mounted on the shock-absorbing bearers and fitted with thrust reversers. Auxiliary power unit is fitted in the tail root above the central engine, using same intake and exhaust. Titanium firewalls are installed.

Three baggage holds (two pressurized and one unpressurised) have capacity of 21.5+16.5+5.0m³. For the two pressurized compartments baggage may be pre-packed into containers.

The prototype (CCCP-85000) was built at the "Opyt" factory workshop (next to Tupolev's design offices) in Summer 1968. It was transported disassembled to Zhukovskij where after reassembly and ground trials it took off for the first flight (pilot Yuri Sukhov) on October 3, 1968. At that time production blueprints were ready.

First potential manufacturer (Moscow Plant N°30) was rejected due to short runway and pressure form other programs. Production was established at Samara (than Kuibyshev) Plant N°18, where assembly of the last Tu-114 was under way. Since 1968, the Tu-154 and its variants kept Plant N°18 busy for more than a quarter of century.

First five Tu-154s (pre-production CCCP-85005 to 85009) were delivered to Aeroflot in October/November 1970. Those aircraft were used to develope engineering and operating procedures and initial crew training. In May 1971 they began to operate as cargo and mailplane. This was a standard USSR routine to operate new aircraft for at least one year before entering passenger service. Flights were performed on routes from Vnukovo airport to Khabarovsk (via Sverdlovsk, Novosibirsk, and Irkutsk), to Sochi, Mineralnye Vody and Simferopol.

As a matter of historical interest, one of the first five Tu-154 (CCCP-85007) continued its service with Vnukovo until the end of 1993 when it was retired.

In February 1972 Tu-154 performed first regular passenger flight from Vnukovo to Mineralnye Vody. In November - first international flight from Sheremetievo to Prague. At this time, the Management of International Air Services (TsUMVS) separated from the Aeroflot. Within a year new management established twelve international routes linking Moscow with major European cities.

At this moment a bad news cane from the SibNII, where extensive fatigue tests were performed on the Tu-154 airframe and wing. Airframe was fine, but the wing had no chances to meet design goals (30,000 flight hours or 20,000 flight cycles). It even could not be upgraded to approach those goals. Entire new wing was needed. 120th Tu-154 was well advanced on the production line, and the situation was close to the industrial disaster for Tupolev. What happened?

• Belief of design bureau that modification of existing construction can meet later needs. "Build it for static loads - and we'll develope it for service life!"
• Wrong alloy (V95) was chosen for the wing lower panel. It had excellent static properties but in active service showed major fatigue and cracks much sooner than expected.
• Normal experience of the industry allowing extrapolation of static tests to the service conditions was proven wrong for new, more demanding flight envelope.

Tupolev sources today say that only state-funded industry could overcome such a blow. After complete redesign, new wing was fitted to all 120 Tu-154s. Such an effort could easily bankrupt most Western manufacturers.

While the aircraft were grounded, their control systems were upgraded also. Modifications allowed to certify Tu-154 for ICAO Category II automatic landings. First series upgrade with new passenger cabin arrangement for 168 passengers was designated Tu-154A.

In May 1972 first two Tu-154 were purchased by foreign airline - Balkan Bulgarian. The demand was raised to extend aircraft service life and make some other changes. Thus the Tu-154B came to life, and Balkan became the first carrier to operate Tu-154B on the transatlantic.

Upgrades of the powerplant and equipment, specialized and experimental conversions resulted in more than 20 modifications of the plane. By mid-1995, 606 Tu-154s (A, B types) and 307 Tu-154Ms were completed, although near 10 remain unsold. There are still some upgrades under discussion, but even without them Tu-154 is expected to be around for another 20 years.

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Modified July 3, 2001

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