Almost 60 years ago, it was thought that it was impossible to break the sound barrier. However, shortly after the success of the X-1, programs were already being prepared to take us beyond Mach 1 and into supersonic flight (Mach 1-Mach 5). However, to cross the next hypersonic flight barrier (any speed above Mach 5), drastic problems in design, propulsion, and construction materials that were not currently available would have to be overcome. With years of research and testing, these obstacles were finally overcome with the recent successful Mach 9.8 flight achieved in November 2004. Powered by the Scramjet (supersonic combustion ramjet), NASA’s X-43A test vehicle touched a realm. flight that is rarely found by air-breathing aircraft, hypersonic flight. Since the X-43’s incredible thrust potential is produced by an engine that has no compressors or moving parts, scientists and countries alike are intrigued to see how this technology can be applied to future goals and projects.
Scramjets are not a new idea. Although the most exciting developments and successes have taken place more recently, the concept has been actively pursued since the 1940s. With government supersonic flight programs such as the F-80 Shooting Star, Republic XF-103 and X-15 , valuable information was obtained on the performance of the ramjet / scramjets. His advances in the study of hydrocarbon-fueled engines alone have helped scramjet technology reach its current state of development.
Scramjet engines are a far cry from the conventional turbine jet engine. Air enters both engines and is compressed. Fuel is added to the compressed air, ignited, and blown out the rear of the engines. This is basically the only thing the two engines have in common. However, if hypersonic flight is to be achieved, it is necessary to make comparisons with this and other power plants to see why the scramjet is the answer for hypersonic propulsion.
With the successful demonstration of these engines by the United States and other countries, many possibilities are now achievable. From precision guided missiles to Mach 10 flights and the proposed X-43B, the technology is here to stay. If funding can be secured, new generations of long-range bombers, rapid-reaction cruise missiles and a space launch system could be made that could reduce the costs associated with propulsion of astronauts and payload to space to a hundredth. part of current prices. Civilization continues to live by faster and more efficient means of transportation and with scramjet-powered vehicles, the hypersonic barrier now doesn’t seem impossible. With promise, scramjet-powered vehicles could one day live up to the aggressive policy goals declared by President Reagan in 1986 regarding the National Aerospace Plane, “To provide trips from New York to Tokyo in two hours.” Talk is cheap though, and one thing scramjets have definitely proven, low-cost scramjet research and development doesn’t exist.
