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Article: Turbulence in the fast lane.(Hypersonic Aircraft)
- Article from:
- USA TODAY
- Article date:
- June 1, 2005
CopyrightCOPYRIGHT 2005 Society for the Advancement of Education. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information)
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Although NASA's X-43A and other hypersonic airplanes uses air-breathing engines and fly much like 747s, there is a big difference between ripping air at Mach 10 (around 7,000 mph) and cruising through it at 350 mph. These differences are even more pronounced when hypersonic aircraft sip rarified air at 100,000 feet, while commercial airliners gulp the much thicker stuff at 30,000.
Aerothermodynamic heating is a very big deal at Mach 10. The critical point comes where air changes from flowing smoothly across a surface (laminar flow) to when it becomes chaotic (turbulent flow). Aerothermodynamic heating largely determines the engine size, weight, choice of ...