Thursday, April 19, 2012
A recent issue of Aviation Week reported that NASA has demonstrated a break-through in the design of aircraft that may allow overland supersonic flights of both passenger and business jets.
“The tests involved scale models of small supersonic airliners designed by Boeing and Lockheed Martin and are aimed at entry into service about 2025. Although the measured shock waves signatures are at the high end of what would be publicly acceptable, they proved the design tools could produce a supersonic business jet capable of unrestricted overland flight,” says Peter Coen, NASA’s Supersonic Fixed Wing project manager.
The article continues with the information that “NASA’s original goal (of noise production) was 65 PNLdB (Perceived Noise Level); 70 PNLdB is widely regarded as the threshold for public acceptance of routine overland supersonic flight,” and that “Boeing and Lockheed are now working under Phase 2 contracts to refine the off-track shock wave signatures of their designs to reduce sonic boom over the full 60-mile wide “carpet.”
Those of us living in south Austin in the 1950’s and ‘60’s remember the continual sonic booms from the military jets at Bergstrom AFB, and the damage it did to our windows, and the community controversy that it created. This was the era of the “Cold War,” and the complaints were continually brushed off by the Air Force justifying the noise by the mantra that “this is the Sound of Freedom.”
This “Sound of Freedom” was taken to court by the citizens of Oklahoma City in 1964 after “Operation Bongo II” subjected citizens to six months of continuous sonic booms, and the Air Force was forced to pay damages.
The citizens of Bastrop County may have a similar situation if the Central Texas Airport is constructed and operated with the potential of trans-sonic business aircraft using this facility and the surrounding air space. Imagine, not only the continual din of hundreds of aircraft at low altitude over Elgin and Cedar Creek, but also the sonic booms as they accelerate to cruising speed.
And remember, the “carpet” of the sonic boom is 60 miles wide.
This isn’t the reassuring “Sound of Freedom.”
It’s the destructive “Sound of Money.”