Regular commercial supersonic flight ended with the iconic Concord in 2003 but NASA in particular has been pushing research into a new class of quieter, greener high-speed aircraft.

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This week the space agency said it invested $2.3 million for eight research projects that will address sonic booms and high-altitude emissions from supersonic jets.

NASA’s Commercial Supersonic Technology Project, which picked the new projects, focuses on developing sonic boom reduction methods and defines the necessary approaches or techniques for objectively assessing the levels of sonic boom acceptable to communities living in the vicinity of future commercial supersonic flight paths.

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The titles of the studies and details of the awards include:

Global Environmental Impact of Supersonic Cruise Aircraft in the Stratosphere

$1.2 million over four years

Massachusetts Institute of Technology, Cambridge, Massachusetts

The Influence of Turbulence on Shaped Sonic Booms

$1.2 million over three years

Wyle Laboratories, Arlington, Virginia

Sonic Boom Display

$698,000

Rockwell Collins, Columbia, Maryland

Pilot Interface for Mitigating Sonic Boom

$686,000 over two years

Honeywell, Golden Valley, Minnesota

Quiet Nozzle Concepts for Low Boom Aircraft

$575,000 over two years

University of California, Irvine

Evaluation of Low Noise Integration Concepts and Propulsion Technologies for Future Supersonic Civil Transports

$599,000 over two years

GE Global Research, Niskayuna, New York

Waveforms and Sonic Boom Perception and Response Risk Reduction

$337,000 for one year

Applied Physical Sciences, Groton, Connecticut

Risk Reduction for Future Community Testing with a Low-Boom Flight Demonstration Vehicle

$393,000 over one year

Fidell Associates, Woodland Hills, California

NASA noted that the awards to Applied Physical Sciences and Fidell Associates are guaranteed only for the first year. One of the two will be selected to receive about $450,000 a year for two more years.

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