Commercial Supersonic Technology Project

The Commercial Supersonic Technology (CST) project focuses on sonic boom reduction methods and approaches. Its primary goal is to develop and validate 

tools, technologies and concepts to overcome the 

barriers to practical supersonic commercial aircraft.

The project’s scope includes design tools for vehicles 

with low sonic boom, and defines the necessary 

approaches and techniques for objectively assessing 

the levels of sonic boom acceptable to communities 

living in the vicinity of future commercial supersonic 

flight paths. Knowledge and data from this work 

will inform the efforts of both national and international regulatory organizations in the development of 

design standards for future supersonic commercial 

aircraft. 

In addition, CST research lays the groundwork for 

overcoming other challenges facing commercial 

supersonic flight including energy efficiency, reduced 

pollutants emitted into the atmosphere, and acceptable noise levels in the airport area.

Although primarily focused on sonic boom mitigation, the CST conducts research into other barriers to 

commercially viable supersonic vehicles including: 

cruise efficiency, airport noise, emissions, aeroelastic 

behavior, and airspace integration. To achieve its 

objectives, the project is organized around research 

themes necessary to advance the state-of-the-art:

•	 Integrate design solutions for revolutionary highspeed aircraft

•	 Understand and measure sonic boom community

 response

•	 Minimize the airport community noise impact of

high-speed aircraft

•	 Reduce or eliminate the impact of high-altitude

emissions

•	 Maximize the cruise efficiency of high-speed

airframes and propulsion systems

•	 Develop multi-discipline solutions to the impact

of aeroservoelasticity on high-speed aircraft

•	 Develop flight systems technologies to maximize

the capabilities of high-speed aircraft in the 

National Airspace System

Technical challenges for the 2013-2017 timeframe 

are drawn from the project’s focus on a design for 

a low-sonic-boom airframe and on developing an 

understanding of community response to sonic 

booms with the intent of preparing for a potential 

flight demonstration of low-boom technology and 

acceptability. Additionally, the project will capitalize 

on previous success in the airport community noise 

research theme.

Scientists and engineers at NASA Armstrong Flight 

Research Center, Edwards, California, are working

to understand the characteristics of sonic booms and 

how they might affect future designs for commercial 

supersonic aircraft. Past efforts included the Superboom CausticAnalysis and Measurement Project

(SCAMP), Waveforms and Sonic boom Perception

and Response (WSPR), and Farfield Investigation of

No Boom Threshold (FaINT). SCAMP investigated

This schlieren image dramatically displays the shock wave of a supersonic jet flying over the Mojave Desert. Researchers used NASA-developed image processing software to remove the desert background, 

then combined and averaged multiple frames to produce a clear picture of the shock waves. 
FS-2015-10-107 AFRC

National Aeronautics and Space Administration

Armstrong Flight Research Center

P.O. Box 273

Edwards, California 93523

NASA Facts

focused sonic booms, which are produced when an airplane accelerates or maneuvers rapidly during supersonic flight, and create 

louder than normal booms. The WSPR project called upon 100

volunteers to share their impressions of booms made by a NASA 

F-18 flying overhead at EdwardsAir Force Base. The FaINT investigation examined the phenomenon of evanescent shock wave

fragments that produce a faint rumble.

Researchers have also used a technique called schlieren photography to create images of supersonic shock waves. Flow visualization is one of the fundamental tools of aeronautics research, and 

schlieren photography has been used for many years to visualize 

air density gradients caused by aerodynamic flow. This technique 

is usually used with a model in a wind tunnel. Capturing schlieren 

images of a full-scale aircraft in flight is much more challenging.

Two Armstrong projects, Air-to-air Schlieren Imaging System (ASIS) and Ground-to-Air Schlieren Photography System 

(GASPS), employed methods using the sun’s edge as a bright light 

source. These produced adequate results, but only two observations of each shockwave could be made as the target aircraft 

crossed the left and right sides of the sun. Two other experiments

used a speckled background upon which to observe shock wave 

patterns. Air-to-air Background Oriented Schlieren (AirBOS) 

involved using a high-speed camera on the underside of a NASA 

Beechcraft B200 King Air to capture images of a supersonic target 

aircraft passing underneath, using desert vegetation as a natural 

speckled background. A ground-based system called Background 

Oriented Schlieren using Celestial Objects (BOSCO) captured 

images of supersonic target aircraft with the sun’s filtered disk 

providing the necessary background. Modern image processing

methods proved key to revealing ever more detailed pictures, and 

researchers found ground-based methods to be significantly more 

economical than air-to-air methods.

Research has also led to development of a method to map sonic

boom effects in real time. Cockpit Interactive Sonic Boom Display

Avionics (CISBoomDA) is a revolutionary software system capable of displaying the location and intensity of shock waves caused 

by supersonic aircraft. Integrated into aircraft cockpits or groundbased control rooms, this technology could be used by pilots of 

future supersonic aircraft to place loud booms in specific locations, 

minimizing their impact in populated areas. This software application calculates an airplane’s sonic boom footprint using vehicle 

and flight parameters and current atmospheric conditions. Processed data provides real-time information regarding location and 

intensity of the airplane’s shock wave, enabling pilots to make the 

necessary flight adjustments to control the location and intensity of 

sonic booms. The CISBoomDA software can be used on currentgeneration supersonic aircraft, which generate loud sonic booms, 

but of greater interest are future-generation low-boom aircraft, 

anticipated to be quiet enough for flight over populated zones.

One of the instruments used for the WSPR project is the SNOOPI 

sonic boom recorder, short for Supersonic Notification of Overpressure Instrumentation, mounted inside a commercial doghouse. 

SNOOPI records local sonic booms by date, time and intensity, 

24-hours a day, seven days a week. 

CISBoomDA software is used to integrate vehicle and environmental data with a real-time, local-area moving-map capable 

of displaying an aircraft’s sonic boom footprint at all times and 

predicting effects of various maneuvers. This allows pilots to select 

a flight path or parameters to either avoid generating a sonic boom 

or to place the sonic boom in a specific location.