Concorde

context: en: Before Concorde's flight trials, developments in the civil aviation industry were largely accepted by governments and their respective electorates. Opposition to Concorde's noise, particularly on the east coast of the United States, forged a new political agenda on both sides of the Atlantic, with scientists and technology experts across a multitude of industries beginning to take the environmental and social impact more seriously. Although Concorde led directly to the introduction of a general noise abatement programme for aircraft flying out of John F. Kennedy Airport, many found that Concorde was quieter than expected, partly due to the pilots temporarily throttling back their engines to reduce noise during overflight of residential areas. Even before commercial flights started, it had been claimed that Concorde was quieter than many other aircraft. In 1971, BAC's technical director was quoted as saying, "It is certain on present evidence and calculations that in the airport context, production Concordes will be no worse than aircraft now in service and will in fact be better than many of them."Concorde produced nitrogen oxides in its exhaust, which, despite complicated interactions with other ozone-depleting chemicals, are understood to result in degradation to the ozone layer at the stratospheric altitudes it cruised. It has been pointed out that other, lower-flying, airliners produce ozone during their flights in the troposphere, but vertical transit of gases between the layers is restricted. The small fleet meant overall ozone-layer degradation caused by Concorde was negligible. In 1995, David Fahey, of the National Oceanic and Atmospheric Administration in the United States, warned that a fleet of 500 supersonic aircraft with exhausts similar to Concorde might produce a 2 percent drop in global ozone levels, much higher than previously thought. Each 1 percent drop in ozone is estimated to increase the incidence of non-melanoma skin cancer worldwide by 2 percent. Dr Fahey said if these particles are produced by highly oxidised sulphur in the fuel, as he believed, then removing sulphur in the fuel will reduce the ozone-destroying impact of supersonic transport.Concorde's technical leap forward boosted the public's understanding of conflicts between technology and the environment as well as awareness of the complex decision analysis processes that surround such conflicts. In France, the use of acoustic fencing alongside TGV tracks might not have been achieved without the 1970s controversy over aircraft noise. In the UK, the CPRE has issued tranquillity maps since 1990.Some sources say Concorde typically flew 17 miles per U.S. gallon (14 L/100 km; 20 mpg‑imp) per passenger.
qas: question: zh_tw: 什麼飛機預計會產生比實際更多的噪音？
answers: en: text: Concorde'

context: en: Due to its high speeds, large forces were applied to the aircraft during banks and turns, and caused twisting and distortion of the aircraft's structure. In addition there were concerns over maintaining precise control at supersonic speeds. Both of these issues were resolved by active ratio changes between the inboard and outboard elevons, varying at differing speeds including supersonic. Only the innermost elevons, which are attached to the stiffest area of the wings, were active at high speed. Additionally, the narrow fuselage meant that the aircraft flexed. This was visible from the rear passengers' viewpoints.When any aircraft passes the critical mach of that particular airframe, the centre of pressure shifts rearwards. This causes a pitch down moment on the aircraft if the centre of gravity remains where it was. The engineers designed the wings in a specific manner to reduce this shift, but there was still a shift of about 2 metres. This could have been countered by the use of trim controls, but at such high speeds this would have dramatically increased drag. Instead, the distribution of fuel along the aircraft was shifted during acceleration and deceleration to move the centre of gravity, effectively acting as an auxiliary trim control.
qas: question: zh_tw: 飛越臨界馬赫數後，壓力中心會向哪方轉移？
answers: en: text: rearwards

context: en: Situated behind the leading edge of the wing the engine intake had wing boundary layer ahead of it. Two thirds was diverted and the remaining third which entered the intake did not adversely affect the intake efficiency except during pushovers when the boundary layer thickened ahead of the intake and caused surging. Extensive wind tunnel testing helped define leading edge modifications ahead of the intakes which solved the problem.Each engine had its own intake and the engine nacelles were paired with a splitter plate between them to minimise adverse behaviour of one powerplant influencing the other. Only above Mach 1.6 was an engine surge likely to affect the adjacent engine.Concorde needed to fly long distances to be economically viable; this required high efficiency from the powerplant. Turbofan engines were rejected due to their larger cross-section producing excessive drag. Olympus turbojet technology was available to be developed to meet the design requirements of the aircraft, although turbofans would be studied for any future SST.The aircraft used reheat (afterburners) at take-off and to pass through the upper transonic regime and to supersonic speeds, between Mach 0.95 and Mach 1.7. The afterburners were switched off at all other times. Due to jet engines being highly inefficient at low speeds, Concorde burned two tonnes of fuel (almost 2% of the maximum fuel load) taxiing to the runway. Fuel used is Jet A-1. Due to the high thrust produced even with the engines at idle, only the two outer engines were run after landing for easier taxiing and less brake pad wear – at low weights after landing, the aircraft would not remain stationary with all four engines idling requiring the brakes to be continuously applied to prevent the aircraft from rolling.
qas: question: zh_tw: 協和式飛機燃燒掉多少噸燃料？
answers: en: text: two

context: en: The design work was supported by a preceding research programme studying the flight characteristics of low ratio delta wings. A supersonic Fairey Delta 2 was modified to carry the ogee planform, and, renamed as the BAC 221, used for flight tests of the high speed flight envelope, the Handley Page HP.115 also provided valuable information on low speed performance.Construction of two prototypes began in February 1965: 001, built by Aérospatiale at Toulouse, and 002, by BAC at Filton, Bristol. Concorde 001 made its first test flight from Toulouse on 2 March 1969, piloted by André Turcat, and first went supersonic on 1 October. The first UK-built Concorde flew from Filton to RAF Fairford on 9 April 1969, piloted by Brian Trubshaw. Both prototypes were presented to the public for the first time on 7–8 June 1969 at the Paris Air Show. As the flight programme progressed, 001 embarked on a sales and demonstration tour on 4 September 1971, which was also the first transatlantic crossing of Concorde. Concorde 002 followed suit on 2 June 1972 with a tour of the Middle and Far East. Concorde 002 made the first visit to the United States in 1973, landing at the new Dallas/Fort Worth Regional Airport to mark that airport's opening.During testing, Concorde F-WTSB attained the highest altitude recorded in sustained level flight of a passenger aircraft of 68,000 ft, in June 1973.  Concorde G-AXDN attained the highest recorded speed of Mach 2.23 on 26 March 1974, at an altitude of 63,700 ft.
qas: question: zh_tw: 協和飛機 002 號隨後於何時啟程飛往？
answers: en: text: 2 June 1972