The Tupolev Tu-144 (NATO reporting name: "Charger") was one of the world's only two supersonic transport aircraft (SST) to enter civilian service, along with the Concorde, and was constructed under the direction of the Soviet Tupolev design bureau headed by Alexei Tupolev.
The Tupolev Tu-144 (NATO reporting name: "Charger") was one of the world's only two supersonic transport aircraft (SST) to enter civilian service, along with the Concorde, and was constructed under the direction of the Soviet Tupolev design bureau headed by Alexei Tupolev. The Tu-144 was outwardly similar to the Aérospatiale / British Aircraft Corporation Concorde, under development at the same time, and there were frequent allegations that Soviet espionage played a key role, giving the Tu-144 the nickname "Concordski". The Tu-144 was Tupolev's only supersonic commercial airliner venture, as the company's other large supersonic aircraft were designed and built to military specifications. All these aircraft benefited from technical and scientific input from TsAGI, the Central Aerohydrodynamic Institute. McDonnell Douglas, Lockheed and Boeing were three other manufacturers who attempted to design SST airliners for the US market during the 1960s, but without success. A prototype (OKB: izdeliye 044 - article 044) first flew on 31 December 1968 near Moscow, two months before the Concorde. The Tu-144 first broke the speed of sound on 5 June 1969, and on 15 July 1969 it became the first commercial transport to exceed Mach two. However, a crash at the 1973 Paris Air Show was a major setback to development. The Tu-144 was introduced into passenger service on 1 November 1977, almost two years after the Concorde, but was soon withdrawn after just 55 scheduled passenger flights due to potentially severe problems with aircraft safety and was not re-introduced to service. Although the Tu-144 was technically broadly comparable to the Concorde, it lacked a passenger market within the Soviet Union and service was halted after only 102 scheduled flights (55 passenger flights, the rest cargo). The Concorde remained in service until 2003, being withdrawn three years after a crash near Paris (25 July 2000), the only loss of an SST in civilian service. The Soviets published the concept of the Tu-144 in an article in the January 1962 issue of the magazine Technology of the Air Transport. The air ministry started development of the Tu-144 on 26 July 1963, following approval by the Council of Ministers 10 days earlier. The project started two years later than the Concorde. The plan called for five flying prototypes to be built in four years. The first aircraft was to be ready in 1966. Despite the close similarity in appearance of the Tu-144 to the Anglo-French supersonic aircraft, there were significant differences in the control, navigation and engine systems. In areas such as range, aerodynamic sophistication, braking and engine control, the Tu-144 lagged behind the Concorde. While the Concorde utilized an electronic engine control package from Lucas, Tupolev was not permitted to purchase it for the Tu-144 as it could also be used on military aircraft. The Concorde's designers used the fuel of this airliner as the coolant for air conditioning the cabin and the hydraulic system (see Concorde#Heating issues for details). Tupolev installed additional equipment on the Tu-144 to accomplish this, increasing the weight of the airliner. Tupolev continued to work to improve the Tu-144. Many substantial upgrades and changes were made on the Tu-144 prototype (serial number 68001). While both the Concorde and the Tu-144 prototype had ogival delta wings, the Tu-144's wing lacked the Concorde's conical camber. Production Tu-144s replaced this wing with a double-delta wing including conical camber, and they added an extra simple but practical device: two small retractable canard surfaces one on either side of the forward section on the aircraft to increase lift at low speed. Moving the elevons downward in a delta-wing aircraft increases the lift, but that also pitches its nose downward. The canard cancels out this nose-downwards moment, thus reducing the landing speed of the production Tu-144s to 315–333 km/h (170-180 kn, 196-207 mph) - however, still faster than that of the Concorde. The NASA study lists final approach speed during performed Tu-144LL test flights as 170 to 181 knots (315 to 335 km/h), however these were approach speeds exercised during test flights specifically intended to study landing effects at maximum possible range of speeds, regardless of how hard and stable the landing can be. As to regular landings, FAA circular lists Tu-144S approach speed as 178 knots (330 km/h), as opposed to BAC/Aerospatiale Concord(e) approach speed of 162 knots (300 km/h), based obviously on the characteristics declared by the manufacturers to Western regulatory bodies. However it is open to an argument how stable was Tu-144S at the listed airspeed. In any event, when NASA subcontracted Tupolev bureau in the 1990s to convert one of the remaining Tu-144D to a Tu-144LL standard, the procedure set by Tupolev for landing defined the Tu-144LL "final approach speed... on the order of 360 km/hr depending on fuel weight." Brian Calvert, the Concorde's technical flight manager and its first commercial pilot executing several inaugural flights, cites final approach speed of a typical Concorde landing to be 155 to 160 knots, i.e. 287 to 296 km/h. Lower Concorde landing speed compared to Tu-144 is due to the Concorde's more refined design of the wing profile that provides higher lift at low speeds without degrading supersonic cruise performance — a feature often mentioned in Western publications on the Concorde and acknowledged by Tupolev designers as well. At the Paris Air Show on 3 June 1973, the development program of the Tu-144 suffered severely when the first Tu-144S production airliner (reg 77102) crashed. While in the air, the Tu-144 underwent a violent downwards maneuver. Trying to pull out of the subsequent dive, the Tu-144 broke up and crashed, destroying 15 houses and killing all six people on board the Tu-144 and eight more on the ground. The causes of this incident remain controversial to this day. A popular theory was that the Tu-144 was forced to avoid a French Mirage chase plane which was attempting to photograph its canards, which were very advanced for the time, and that the French and Soviet governments colluded with each other to cover up such details. The flight of the Mirage was denied in the original French report of the incident, perhaps because it was engaged in industrial espionage. More recent reports have admitted the existence of the Mirage (and the fact that the Russian crew were not told about the Mirage's flight) though not its role in the crash. However, the official press release did state: "though the inquiry established that there was no real risk of collision between the two aircraft, the Soviet pilot was likely to have been surprised." Howard Moon also stresses that last-minute changes to the flight schedule would have disoriented the pilots in a cockpit with notable poor vision. He also cites an eyewitness who claims the co-pilot had agreed to take a camera with him, which he may have been operating at the time of the evasive maneuver. Another theory claims that the black box was actually recovered by the Soviets and decoded. The cause of this accident is now thought to be due to changes made by the ground engineering team to the auto-stabilisation input controls prior to the second day of display flights. These changes were intended to allow the Tu-144 to outperform the Concorde in the display circuit. Unfortunately, the changes also inadvertently connected some factory-test wiring which resulted in an excessive rate of climb, leading to the stall and subsequent crash. A third theory relates to deliberate misinformation on the part of the Anglo-French team. The main thrust of this theory was that the Anglo-French team knew that the Soviet team were planning to steal the design plans of the Concorde, and the Soviets were allegedly passed false blueprints with a flawed design. The case, it is claimed, contributed to the imprisonment by the Soviets of Greville Wynne in 1963 for spying. Wynne was imprisoned on 11 May 1963 and the development of the Tu-144 was not sanctioned until 16 July. In any case, it seems unlikely that a man imprisoned in 1963 could have caused a crash in 1973. Although its last commercial passenger flight was in 1978, production of the Tu-144 did not cease until six years later, in 1984, when construction of the partially complete Tu-144D reg 77116 airframe was stopped. During the 1980s the last two production aircraft to fly were used for airborne laboratory testing, including research into ozone depletion at high altitudes. In the early 1990s, a wealthy businesswoman, Judith DePaul, and her company IBP Aerospace negotiated an agreement with Tupolev and NASA, (also Rockwell and later Boeing). They offered a Tu-144 as a testbed for its High Speed Commercial Research program, intended to design a second-generation supersonic jetliner called the High Speed Civil Transport. In 1995, Tu-144D [reg 77114] built in 1981 (but with only 82 hours and 40 minutes total flight time) was taken out of storage and after extensive modification at a total cost of US$350 million was designated the Tu-144LL (Russian: Летающая Лаборатория — where LL is an abbreviation for Flying Laboratory). It made a total of 27 flights in 1996 and 1997. In 1999, though regarded as a technical success, the project was cancelled for lack of funding. The Tu-144LL was reportedly sold in June 2001 for $11 million via online auction, but the aircraft sale did not proceed after all — Tejavia Systems, the company handling the transaction, reported in September 2003 that the deal was not signed. The replacement Kuznetsov NK-321 engines (from the Tupolev Tu-160 bomber) are military hardware and the Russian government did not allow them to be exported. At the 2005 Moscow Air & Space Show, Tejavia founder Randall Stephens found the Kuznetsov NK-321 engine on display, and the Tu-144LL rusting on Tupolev's test base at the Gromov Flight Test Center. In late 2003, with the retirement of the Concorde, there was renewed interest from several wealthy individuals who wanted to use the Tu-144LL for a transatlantic record attempt; but Stephens advised them of the high cost of a flight readiness overhaul even if military authorities would authorize the use of NK-321 engines outside Russian Federation airspace. The last two production aircraft remain at the Tupolev production plant in Zhukovsky, reg 77114 and 77115. In March 2006, it was announced that these airframes had been sold for scrap. Later that year, however, it was reported that both aircraft would instead be preserved. One of them could be erected to a pedestal near Zhukovsky City Council and TsAGI or above the LII entrance from the Tupolev avenue. General characteristics * Crew: 3 * Capacity: 120-140 passengers, but normally 70~80 passengers * Length: 65.50 m (215.54 ft) * Wingspan: 28.80 m (94.48 ft) * Height: 10.50 m (34.42 ft) * Wing area: 438.0 m² (4,715 ft²) * Empty weight: 85,000 kg (187,400 lb) * Loaded weight: unknown () * Max takeoff weight: 180,000 kg (397,000 lb)) * Powerplant: 4× Kolesov RD-36-51 afterburning turbojet, 200 kN (44,122 lbf) each * Fuel capacity: 70,000 kg (154,000 lb) Performance * Maximum speed: Mach 2,35 (2,500 km/h, 1,550 mph) * Cruise speed: Mach 2,2 (2,300 km/h, 1,430 mph) * Range: 6,500 km (3,500 nm, 4,000 mi : 2,920 km with full afterburner) * Service ceiling: 18,000 m (59,100 ft) * Rate of climb: 9,840 ft/min (3,000 m/min) (ft/min) * Wing loading: 410.96 kg/m² (84.20 lb/ft²) * Thrust/weight: 0.44