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Why Supersonic Transportation
Many ask the question, why do we need supersonic transportation? Supersonic transportation is a technology that has not been perfected as it raises to many environmental and safety questions to date. The reason for it s existence is speed and time, along with the fact that every technology that is discovered is almost always improved to be quicker and faster. In today s fast paced world we look anywhere we can to save time in our lives. If you could fly From the United States to Europe in half the time of a regular jet airliner for just a small increase in cost, this would appeal to many people. This was the thought of those designing the supersonic aircraft, that it could be done for a reasonable cost and offer people quicker flight times along with airlines could make twice as many flights as a regular jet could in a days time.
History of Supersonic Transportation
The history of Super Sonic Transportation began in the mid 1950 s, when the Russians, French and British began study this yet unknown technology. Supersonic airliner studies commenced in Britain in 1955 when enough aerodynamic progress had been made on lift/drag ratios to allow a commercially feasable aircraft to be considered . The United States was under the reign of the Kennedy administration. They felt Super Sonic Transportation was important enough to do a feasibility study, to tell whether is was a feasible for the United States to pursue this fascinating new element of technology. The hopes of American SST lobby rose at the end of 1962 when the president established a special cabinet-level committee headed by pro-SST Vice-President Lyndon Johnson . The idea being to design and build an SST that would be economically attractive to air passengers. NASA began to do extensive wind tunnel research at its Langley and Ames centers to determine aerodynamic computation, transonic exceleration, stability and the control needed for Supersonic Transport flight. The British and French had begun to do this prior to the United States starting an SST program. In November of 1962 France s Sud-Aviation and the British Aircraft Corporation and their respected governments signed cooperation agreements for the development of their own Supersonic Aircraft. In February 1965 they began construction of the first two prototypes one French and the other British. So it seems the development of Supersonic Transport soon became a race to see who could output the first Supersonic Transport. The race was won by the Russian s, who on December 31, 1968 made a maiden voyage with the Tupolev 144 Supersonic Transport. This aircraft went into service in late 1969, carrying mail and freight and on November 1, 1977 began to fly its first passengers with a flight from Moscow to Alma-Ata, Kazakhstan. On December 11, 1967 the first prototype (British-French) Concorde is unveiled in Toulouse and the first Concorde (French #001) took flight on March 2, 1969. The second Concorde (British #002) was flown shortly afterwards on April 9, 1969 despite the inherent problems that still plagued the SST s such as noise, sonic boom, fuel consumption and cost. In 1974 an Air France Concorde flew from Boston to Paris, leaving at the same time as a 747 headed from Paris to Boston. The Concorde returned to Boston after an hour wait on the ground in Paris and beat the 747, completing the round trip in 11 minutes under the one way 747 by 11 minutes. By September 1, 1975 the Concorde was making regular flights although not with passengers, and recorded four Atlantic crossings in one day, making two round trips from London to Newfoundland. In January, 1976 British Airways and Air France began to regularly scheduled passenger flights, inaugurating a new era in Supersonic passenger travel. The United States Supersonic Transport program never really got off the ground as Boeing Airplane Company developed plans to build a faster and larger aircraft which would carry up to 250 passengers at a speed of Mach 2.7 and would weigh 350 tons. This plan was aborted just five months before the first prototype was to be built because of concern for costs, even though funded largely by the United States Government. The United States felt that the SST program was vulnerable for several reasons. The ability to show profitable operation in the 1960 s was a very difficult task along with the problems of noise and possible atmospheric pollution along with other environmentally questionable reasons put and end to the pursuit of the American supersonic and the SST program was terminated in 1971.
Since commencing operations in 1973, the Concorde fleets of Air France and British Airways, each with seven aircraft, have achieved a combined aggregate of more than 100,00 hours of flying at supersonic speeds(Barbaux et al 1994). In this regard, Concorde remains the only Mach 2.0 (2120 kph) supersonic transport (SST) that can cover 6000km in 3 hours carrying 100 passengers . The Russian TU-144 was grounded in 1985 after a crash at a 1973 air show in Le Bourget. It was made airworthy again 11 years later with a joint venture between the United States and Russia to use it for testing to develop a new high speed civil transport.
General Air Transportation vs. Supersonic Transportation
The ratio of general air transportation compared to that of supersonic transportation is a very small one. In 1960 the total of aircraft available for service, domestic and international combined was 2,135 compared to zero supersonic transports available at that time. By the late 1970,s there were a total of sixteen supersonic transports compared to 2,690 total available aircraft. As of 1996 there are a total of 14 Concorde s in service by Air France and British Airways and 5,961 domestic and international aircraft in service.
Number of Aircraft Available for Service
1960 1970 1980 1990 1994 1995 1996
Domestic/International 2,135 2,690 2,818 4,727 5,221 5,567 5,961
Majors N N 2,071 3,854 4,085 4,039 4,442
Nationals N N 432 650 819 1,143 1,167
Regionals N N 315 223 317 385 372
One reason for the low number of supersonic transports in service today is caused by the fact that development costs had exceeded prior expectations, which costs Air France and British Airways 4 billion dollars (five times the initial estimate). The builders of the Concorde had expected to recoup there investment by appealing to the cream of profitable passengers, but it was not to be. The main reason being the Boeing 747 which went into service in 1970. This jumbo jet could carry four times the passengers compared to the Concorde s 100, consumed less than half the fuel and half of the maintenance costs as the Concorde. The year the Concorde made it s first flight the cost of a barrel of oil was 1.67, and by 1976 it had risen to $11.51 a barrel, and by 1980 it had risen to 36.15 a barrel, which destroyed the economic assumptions that were made when the Concorde was designed. Also the supersonic jets have to use longer runways than other jets and at most airports around the world this is not yet an option and would take great costs to each airport to facilitate these needs. The other factors which have bogged down the forward progress of supersonic transportation compared to general aircraft transportation were the effects it has on our environmental system. The concerns were based the fact of the sonic booms that the aircraft emitted along with the concerns about the high altitude, gas guzzling flights would deplete the ozone layer. The other reason for the SST not yet becoming a replacement for our standard jets is the manpower required to keep these aircraft marvels in the air. British Airways operates a fleet of seven Concorde s that are maintained by a team of 220 engineers. The aircraft, more than 20 years old, are maintenance intensive, requiring 56 man-hours of maintenance per flying hour, which equates to 5-8 times that of a typical Boeing 747 .
Has SST solved problems?
Without a doubt, Concorde was one of the biggest steps in progress of aviation, equivalent in it s impact to the first controlled flight by the Wright brothers . Also the Concorde has probably generated more noise and environmental pollution-hate than it has contributed good to the industry of passenger aircraft. It has shown that an aircraft of it s magnitude is possible and has opened up ideas for future supersonic transport. The Concorde flies above the ceiling of any weather problems and flies were other general aircraft are capable, so the big technological wonders do not interfere with its smaller counterparts airspace. Even though the supersonic transports of this world have not really solved any immediate needs of our world of aviation, there are few who would disagree that the Concorde is one of the first fruits of international collaboration had proved to be a technological success.
Supersonic Transports and the Future
While the future of the Concorde is in jeopardy because of it s recent accident, and the first and it s first with fatalities involved, the future of the SST looks bright. Many experts believe that it would be capable to reduce the cost of producing an SST today, and in 10 years time a strong demand will be needed for an SST that will fly faster, and carry more passengers than our existing supersonic aircraft. Currently two groups are in the process of designing plans for a new improved SST. The United States High Speed Civil Transport (HSCT) program is involved with Boeing Airplane Company, which is getting strong support from the National Aeronautics and Space Administration to design a new era SST. Also the European Supersonic Research Program (ESRP) who is in association with Aerospatiale, a French based company who is heading the design of their new SST. The secret to the success of the new supersonic transport will undoubtedly be the control of operating costs and the fares will have to be competitive with their subsonic siblings, at least not exceeding 15% of the current subsonic rates. The other concern for the future SST will be that it can use existing runways that subsonic jets use, and have quicker turnaround times. Not to mention the fact that problems of material technologies, engine emissions and propulsion and the reduction of noise still must be addressed with the development of a future SST. In Japan the New Energy and Industrial Technology Development Organization (NEDO) is developing a new generation Concorde that will fly from New York to Tokyo in 3 hours at a speed of Mach 5. This new Japanese aircraft will be powered by the Hypersonic Transport Propulsion System (HYPR), this new technology merges the capabilities of turbojets and ramjets. The idea of the this new technology is that the turbo jets will power the plane at lower speeds (Mach 3 and below) and the ramjets will take over at higher speeds (Mach 3 and above). Although tests at General Electric have been successful, the problem of coordinating these two engines still remains a problem.
Another idea for a new hypersonic vehicle which would skitter along the top of the atmosphere like a stone, at the speed of Mach 10, is the Hypersoar. Not yet into the full development stage, the concept was developed and mainly promoted by Jason Speyer, an aerospace engineer at the University of California, Los Angeles. The plane would make a regular take of on a regular runway and then jet into the atmosphere and skitter along with engine assist until reaching the point that it needed to jet back to earth.
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