What is the different between supersonic flight and subsonic flight? The term “supersonic” and “subsonic” are used to describe the travel speed in Mach unit in which “supersonic” is used for the speed between Mach 1 and 5 while “subsonic” is for the speed below Mach 1(Smith, 2009, para.2)When a plane is flying at supersonic speed, it is flying faster than sound. The major difference in a supersonic aircraft is the design principal. The most important thing to consider when building a supersonic aircraft is airflow: “Managing that airflow is especially troublesome as a plane approaches the speed of sound… The faster the plane travels, the more difficult it is to push the craft through the air and the more fuel the plane's engines need to fly a given distance” (Dillow, 2014). The Concorde is an example of a supersonic aircraft with is thin body and delta-shaped wings.
Figure 1: Concept of the Concorde and the TU-144. (TU-144, n.d)
Before going deep into the problem, it is important to have an overview at the history of supersonic flight. Supersonic transport or SST came into development soon after World War II. During the 50s’, there were four nations competing in this new industry: France, Britain, American, and the Soviet Union. However, there were only 3 sides in this competition as Britain and France agreed on a joint development program (Drake & Purvis, 2001, p.3). The France and Britain collaboration resulted in the legendary Concorde, the name that everyone always mention when talking about supersonic transport. In the far-east, the Soviet Union worked on a similar design to the Concorde, called TU-144. In 1968, the TU-144 had its first flight on 31 December, one year earlier than the Concorde. Meanwhile in the United States, the supersonic program stopped before a prototype was made due to the lack of funding from the US government (p.4). This left only the Soviet Union against the French and British. In 1975, the TU-144 began its first commercial flight. It is followed by the Concorde one year later. Due to numerous difficulties and disadvantages, both planes failed to compete with the newly launched Boeing 747. In 2003, the Concorde program was cancelled, signifying an end to the first generation of supersonic transport (p.5). In the end, supersonic transports proved to have too many disadvantages that outweigh its advantages.
The first obstacle to the development of supersonic transport is its environment impact. One of which is noise pollution, the result of a phenomenon called “sonic boom” According to NASA, “A sonic boom is the thunder-like noise a person on the ground hears when an aircraft or other type of aerospace vehicle flies overhead faster than the speed of sound or supersonic”( NASA, 2014, para.1). In a report by the British Working Group on Noise from Air Traffic in 1976, Concorde’s sonic boom “often exceeded 110PHdB above the airport in 1976”(“Noise”, 2004, para.1). Out of 35 planes taking off from Heathrow Airport, 21...