Classic Jetliners: The Tupolev Tu-144

Pose the question about the earliest and quickest commercial passenger aircraft, and you’ll find many pointing towards the Concorde as the answer. The reality, however, may come as a surprise. The crown of the first supersonic passenger plane goes to the Tupolev Tu-144, an innovation from Russia. Further astonishing is that the Tu-144 continues to retain its record as the fastest commercial passenger jet ever crafted.

Indeed, the Tupolev outpaces the Aerospatiale BAC Concorde.

That said, the Tu-144 didn’t exactly see a successful run. With only seven units ever manufactured, it was a commercial failure. The aircraft’s safety record was so concerning that even Aeroflot, Russia’s own airline, hesitated to operate it. So, how swift was the Tu-144, and when did it take to the skies?

What is the Tu-144?

As a counter to the French Aerospatiale BAC Concorde, the Russians engineered their own supersonic commercial passenger aircraft, the Tupolev Tu-144. With a top speed of 2,430 km/h and a capacity of 150 passengers across two classes, it holds the edge over the Concorde in terms of speed. Each of its turbojet engines, the Kolesov RD-36-51, produces a thrust of 54,000 lbf. The aircraft is capable of soaring up to a maximum safe altitude of 66,000 feet and can travel a distance of 6,500 kilometers.

Among passenger aircraft, the Tu-144 was one of the last to incorporate a braking parachute. The necessity for the parachute emerged as the aircraft was devoid of a reverse thrust system. While only the crew were provided with ejection seats, it marked the aircraft as the first and sole of its kind in passenger planes.

Operating typically at an altitude of 52,000 feet and cruising at approximately Mach 2, the Tu-144 executed 102 commercial flights, with just over half, 55, carrying passengers. Its first journey into supersonic flight was achieved on 5 June 1969, a whole four months ahead of the Concorde. Following that, on 26 May 1970, it became the first commercial aircraft to surpass Mach 2.

Less Superior than Concorde

In that period, it was a competition of precedence between the Western nations and Russia, with achieving supersonic flight emerging as a significant national achievement. For the Russians, it was an all-or-nothing challenge, even if it compromised the aircraft’s quality and safety.

Tupolev, therefore, had a firm resolve to outpace the Concorde in launching the first operational supersonic passenger aircraft.

For its time, the Concorde was equipped with cutting-edge technology. It had a carbon fiber braking system, semi fly-by-wire control system, and digitized flight control systems, all of which assisted the aircraft to continually modify the shape of its air inlets for optimal efficiency. The design even allowed significant alterations to the shape of the wings mid-flight to enhance efficiency.

However, technologically, the Tu-144 was lagging. It was not just slightly inferior to the Concorde; it barely posed a competition. Being over 20 tons heavier than the Concorde, the Tu-144 was considerably larger and more potent. However, when matched up against the Concorde, the Tupolev Tu-144’s engine management, aerodynamics, and brake performance were clearly lacking.

Despite these shortcomings, the Tupolev Tu-144’s top speed was higher than that of the Concorde.

Interestingly, the Tu-144 had its maiden flight on December 31, 1968, while the Concorde’s first flight took place later, on March 2, 1969.

Design and Performance

Constructed with longevity in mind, the Tu-144 was designed for a service life of 30,000 hours spread over 15 years. The primary structural materials, chiefly aluminum alloys, were carefully selected to handle airframe heating and high temperatures, and set the aircraft’s maximum speed at Mach 2.2. Titanium and non-metallic materials constituted significant proportions of the aircraft’s weight, while the leading edges, elevons, rudder, and the rear fuselage engine-exhaust heat shield were made of either titanium or stainless steel.

Two Engines

The Soviet Union had already designed SSTs for M2.2 before Tupolev received the mandate to develop one. The Kuznetsov NK-144 turbofan was the only engine available at the time that possessed the required thrust and was suitable for testing the aircraft. It took considerable time for the Kolesov RD-36-51A turbojet, an alternative engine started in 1964, to attain acceptable specific fuel consumption and reliability. While afterburners were added to the Concorde to meet its take-off thrust requirement, the Tu-144 used maximum afterburner for take-off and minimum for cruise.

To rectify the problem of lack of take-off thrust and surge margin, the Tu-144S, nine of which were produced, was fitted with the Kuznetsov NK-144A turbofan. Eventually, the Kolesov RD-36-51 turbojet was installed in the Tu-144D, enhancing the aircraft’s range with full payload.

General characteristics
Crew	3
Capacity	150 passengers (11 first class & 139 tourist class)
Length	65.7 m (215 ft 7 in)
Wingspan	28.8 m (94 ft 6 in)
Height	12.55 m (41 ft 2 in)
Wing area	506.35 m2 (5,450.3 sq ft)
Empty weight	99,200 kg (218,699 lb)
Gross weight	125,000 kg (275,578 lb)
Max takeoff weight	207,000 kg (456,357 lb)
Fuel capacity	93,000 kg (205,000 lb)
Powerplant	4 × Kolesov RD-36-51 turbojets, 240 kN (54,000 lbf) thrust each
Performance
Maximum speed	2,500 km/h (1,600 mph, 1,300 kn)
Maximum speed	Mach 2.15
Cruise speed	2,125 km/h (1,320 mph, 1,147 kn)
Cruise Mach number	Mach 2
Range	6,500 km (4,000 mi, 3,500 nmi)
Service ceiling	20,000 m (66,000 ft)
Rate of climb	50 m/s (9,800 ft/min)

Airframe Composition and Testing

The Tu-144 was constructed from parts machined from large blocks and panels, some of which were more than 19 m long. Though touted as advanced design practice during its time, it was later discovered that the large whole-moulded and machined parts contained defects in the alloy’s structure. These defects led to cracking at stress levels below expected thresholds. Cracks, once initiated, quickly spread over many meters, with no design feature to arrest their progression. Such structural failures were observed in two Tu-144S airframes during laboratory testing.

The cause of these defects was traced back to the alloy structure, leading to the unfortunate in-air breakup of the aircraft in the 1973 Paris Air Show Tu-144 crash. Post this discovery, the airframe was reinforced, and the control system was modified to prevent overstressing the aircraft.

1973 Paris Air Show Incident

At the 1973 Paris Air Show, spectators were treated to the performance demonstrations of both the Aerospatiale Concorde and the Tupolev Tu-144. The Concorde was the first to display its capabilities and delivered a seamless performance from lift-off to touch-down. The Tu-144 was up next, but its showcase ended in a disastrous event.

The Tu-144 took off and executed a 360-degree maneuver, followed by a rapid ascent. It then leveled out and initiated its descent. The plan reportedly was to fly close to the ground to display the aircraft’s swift acceleration. However, the aircraft couldn’t handle the pressure and started to disintegrate around 1,500 feet above the spectators, eventually crash-landing in a nearby settlement.

The crash resulted in the loss of all six crew members aboard the plane. Additionally, eight French civilians on the ground lost their lives, and around 60 onlookers suffered severe injuries.

Aeroflot Passengers Didn’t like the Tu-144

Tupolev’s Tu-144 found its first and only customer in Aeroflot, the Russian airline. However, the supersonic aircraft’s tenure with the airline was short-lived. Passengers often complained about the excessive noise produced by the air conditioning and engines. The 5-abreast seating layout of the Tu-144 made it far less comfortable than the 4-abreast Concorde. Frequent issues included non-functioning toilets, faulty tray tables, and sagging blinds.

The aircraft was handed over to Aeroflot in 1975, but it only commenced regular passenger service in 1977. However, due to the aircraft’s tarnished safety record and the barrage of passenger complaints, Aeroflot ceased commercial operations of the Tu-144 in 1978.

Commercial supersonic travel has been on hold since the Concorde’s last flight in 2003, but the aviation industry is keeping tabs on the upcoming Boom Supersonic Overture, expected to be the latest addition to supersonic passenger aircraft once it undergoes production and flight testing. For now, we have only computer-generated images to envision this aircraft.

Hence, the Tupolev Tu-144 maintains its position as the world’s first supersonic passenger aircraft to take to the skies.