Thursday, December 14, 2006

Tupolev Tu-144

Tupolev Tu-144


The Tupolev Tu-144 (NATO reporting name: Charger) was a supersonic transport aircraft (SST) constructed under the direction of the Soviet Tupolev design bureau headed by Alexei Tupolev (1925–2001).

Western media nicknamed the plane Concordski (sometimes Konkordski), sounding like a Russian surname yet still very close to Concorde, to which Tu-144 was visually similar. A prototype first flew on December 31, 1968 near Moscow, two months before Concorde. The Tu-144 first broke the sound barrier on June 5, 1969, and on July 15, 1969 it became the first commercial transport to exceed Mach 2.

Tu-144
Tu-144LL
Type Supersonic airliner
Manufacturer Tupolev OKB
Maiden flight 1968-12-31
Introduced 1975-12-26
Retired 1978-06-01
Primary user Aeroflot
Number built 14

Development

The Russians published the concept of the Tu-144 in the January 1962 issue of Russian „Technology of the Air Transport“-magazine in the article by Seljakov, Oscherov, Istomin and Dobrovsky. Air ministry started the development Tu-144 on 26th July 1963 by the decision document Number 276. The Soviet ministerial council had made the decision 768-271 on the 16th of July 1963. This meant that five flying prototypes were to be built in four years. The first aircraft was to be ready in 1966.

The development of the Tu-144 is claimed to be closely related to industrial espionage against the French company AĆ©rospatiale, which was developing Concorde, although the Tu-144 flew first. When Sergei Pavlov —officially acting as Aeroflot’s representative in Paris—was arrested in 1965, he was in possession of detailed plans of the braking system, the landing gear and the airframe of Concorde. Another agent named Sergei Fabiew, who was arrested in 1977, was believed to have obtained the entire plans of the prototype Concorde back in the mid-60s. However, these were early development plans and would not have permitted the USSR engineers to come up with their own aircraft; the plans could only serve as a general indication of the work of the Concorde design team.

The similarity of the Tu-144 to the Franco-British supersonic aircraft was superficially very great, but the differences in the control, navigation and engine systems were dramatic. Just as the Shuttle Buran program was developed as a response to the Space Shuttle program, but was in the end quite different, the Tu-144 was in some ways a more technologically advanced aircraft. Many substantial upgrades and changes were made on the Tu-144 prototype (serial number 68001).

Another significant difference between Concorde and the Tu-144 is that the Tu-144 wing did not have the complex curves found on that of Concorde, instead using small retractable canard surfaces to manoeuvre at low speeds.

At the Paris Air Show on June 3, 1973 the development programme suffered a severe blow when the first Tu-144S production aircraft (reg 77102) crashed. While in the air it undertook a violent downwards manoeuvre. Trying to pull out of the subsequent dive, the plane broke up and crashed, destroying 15 houses and killing all six on board and eight on the ground.

The causes of this incident remain controversial today. 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 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, though not its role in the crash.

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 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 sabotage 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 Concorde, and the Soviets were allegedly passed blueprints with deliberately introduced design flaws. The case contributed to the imprisonment by the Soviets of Greville Wynne in 1963 for spying[citation needed].

In service

The Tu-144S went into service on December 26, 1975 flying mail and freight between Moscow and Alma-Ata in preparation for passenger services, which commenced in November 1977 and ran a semi-scheduled service until the first Tu-144D experienced an in-flight failure during a pre-delivery test flight, and crash-landed with crew fatalities on May 23, 1978. The Aeroflot flight on June 1, 1978 was the Tu-144's 55th and last scheduled passenger service.

A scheduled Aeroflot freight-only service recommenced using the new production variant Tu-144D aircraft on 23 June 1979, including longer routes from Moscow to Khabarovsk made possible by the more efficient RD-36-51 engines used in the Tu-144D version. Including the 55 passenger flights, there were 102 scheduled Aeroflot flights before the cessation of commercial services.

It is known that Aeroflot still continued to fly the Tu-144D after the official end of service, with some additional non-scheduled flights through the 1980s. One report showed that it was used on a flight from the Crimea to Kiev in 1987[citation needed].

Production

A total of 16 airworthy Tu-144s were built: the prototype Tu-144 reg 68001, a pre-production Tu-144S reg 77101, nine production Tu-144S reg 77102–110, and five Tu-144D reg 77111–115. A seventeenth Tu-144 (reg 77116) was never completed. There was also at least one ground-test airframe for static testing in parallel with the prototype 68001 development.

The Tu-144S model had NK-144 turbofan engines, whereas the later Tu-144D model featured more powerful RD-36-51 engines with better fuel efficiency (particularly during supercruise, not requiring afterburner), and longer range. It was also one of the last commercial airplanes with a brake-parachute, together with early Tu-134.

Models equipped with the NK-144 turbofan engines could not cruise at Mach 2 without the afterburner on. A max cruising speed of Mach 1.6 was possible on "dry" power (afterburner off).

Post-production uses

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. 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 (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 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 plane did not sell after all — Tejavia reported in September 2003 that the deal was not signed. The replacement Kuznetsov NK-321 engines (from the Tupolev Tu-160 bomber) are military items and the Russian government would 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 Concorde, there was renewed interest from several well-heeled people 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 (Article from Aviapedia). Later that year, however, it was reported that both aircraft would instead be preserved.[1]

The only Tu-144 on display outside the former Soviet Union was acquired by the Auto & Technikmuseum Sinsheim in Germany, where it was shipped — not flown — in 2001 and where it now stands, in its original Aeroflot livery, on display next to an Air France Concorde.

Civil operators


Specifications (Tu-144LL with Kuznetsov RD-36-51 engines)

These are the specification for the Tu-144LL with military spec turbofan engines. These engines were non export items..

General characteristics

  • Crew: 3
  • Capacity: 120-140 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: kg (lb)
  • Max takeoff weight: 180,000 kg (397,000 lb)
  • Fuel capacity: 70,000 kg (154,000 lb)

Performance

Orthographically projected diagram of the Tu-144LL.


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