Why doesn't the sky fall down on our heads?. Aydogan Koc

       How it came to the development of large passenger aircrafts?

      Strategic needs during World War 2 led to increased dimensions of bombardment and transport aircraft. After the war, this trend continued in the USA. The six engine Boeing B-47 “Stratojet” military aircraft made its first flight in 1950 in the USA. With a speed of over 950 km/h, this aircraft reached an altitude of 12,300 m and left other fighter planes behind.

      An advanced model of this aircraft, the strategic bomber aircraft B-52 “Stratofortress” exceeded 960 km/h and rose to 16,700 m. With these speed and range capabilities, the B-52 remained the most capable and efficient bomber aircraft of the western world for a long time.

      The "Comet", the first jet powered passenger plane manufactured by British De Havilland in 1949 completed its test flights and started passenger service in 1952. This aircraft, which gained a bad reputation due to several accidents because the cabin structure was not designed for the pressures at high altitude, was completely withdrawn from service in 1954. In 1959, a brand new and safe model of the aircraft with all the problems solved was put on the market. But the opportunity to control the market was lost. In the meantime, the USA was planning military purpose jet powered transport aircraft parallel to Europe. A civil aviation version of the KC135 tanker plane, which resulted from these projects, was manufactured: the Boeing-707. This popular passenger aircraft made its first flight on 15 July, 1954. The secret to success of the Boeing-707, which conquered the passenger plane market, was its better technical performance compared to its closest rival, the DC-8 by Douglas; and the improved British Comet was not yet ready for the market.

      Also known as “Jumbo-Jet”, the large body passenger plane Boeing-747 was a side product of another military project. This passenger plane, designed by Boeing to carry military loads, flew for the first time in 1969. When the military project was awarded to Lockheed for the C-5 “Galaxy”, Boeing quickly transformed its proposed design into the 747 passenger aircraft. Boeing strengthened its market position further towards the end of the 60s by expanding its passenger aircraft family with the medium range Boeing-727 and the short range Boeing-737 aircraft. During this period, the short range French Caravelle aircraft were also very successful in Europe. Plus, the Douglas Aircraft Company emerged as a competitor in the medium range passenger aircraft market with the DC-9 patterned after the Caravelle. In the 70s, other aircraft joined the fleet of wide body passenger aircraft initiated by Boeing. These are the DC-10 by Douglas in 1971, the Lockheed-1011 Tristar in 1972 and the European Airbus A-300 in 1972.

      Today, aircraft designer’s main goals are to be ecological, consume less fuel and carry as many passengers as possible.

       When was the sound barrier broken for the first time?

      Military aviation chose a slightly different path from civil aviation after World War 2. The specifications for military aircraft were high acceleration and superior maneuverability at very high altitude and very high speed.

      The rocket powered aircraft, Bell X-1, was the first aircraft to break through the sound barrier in 1947. Thereafter, the research aircraft X-15 reached 7,200 km/h and rose to 108 km altitude between 1959 and 1968. All these operations at “higher speed and higher altitude” also affected the civil aviation sector. The supersonic passenger aircraft "Corcorde", a joint production of Britain and France, made its first flight in Toulouse in the south of France in 1969. A Concorde was the first passenger plane to break the sound barrier with a speed of 2,200 km/h. For this speed, which was twice the speed of sound, Concorde needed to fly at an altitude of 16 to 18 km. The excessive fuel consumption and limited number of passengers prevented the Concorde from becoming a success. Only 16 aircraft were produced and included in French and British national airline fleets. Yet, it was in service cruising at twice the speed of sound, in intercontinental travel between 1976 and 2003. The only rival of the “Concorde” was from the east block by the Russian made Tupolev TU-144. Although it was not as successful as Concorde, this aircraft made about 100 flights in the Siberian sky and then was removed from the Aeroflot fleet in 1983.