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Human Perception of
Sonic Bccms from Supersonic
Alexandra Louheau Advances in human response research will help pave the way for a new
Address: era nfcammerciul supersanicflight.
Structural Acoustics Branch
NASA Langley Research Center '"""‘°d‘-'°"i°"
MS 453 The lure of faster speeds and reduced travel time for commercial flights may
Hampton, Virginia 23681 come to fruition soon with advances in low-boom technology. The Concorde
USA “was a technological marvel that astounded the world with its beauty of design
and speed, halving passenger flight times to distant destinations” (Rogers and
Em”: Maglieri, 2015). Its last flight on October 24, 2003, ended the first era in supersonic
“'1°“b"“@““5“'g°v commercial travel. Although supersonic flight of the Concorde resulted in loud
sonic booms, decades of low-boom research have demonstrated the feasibility of
adapting the aerodynamic shape and tailoring the off-body pressure distribution
lune‘ Page from a supersonic vehicle to decrease or control the sonic boom, a technique
Address: known as sonic boom shaping. Sparrow (2006) provides a snapshot of the history
Environmental Measurement of sonic boom minimization. With this new technology, research of the human
and Modeling response to sonic boom noise is being conducted to better understand the factors
Volpe National Transportation that contribute to annoyance from sonic boom sounds so that theycan be “shaped”
Systems Center for minimal disturbance, thereby potentially resulting in a new era in supersonic
US Department of Transportation Commercial travel. Indeed, recent advances in understanding and predicting
55 Broadway human perception of sonic booms have coincided with renewed interest from
Cambridge, Massachusetts 02142 industry in pursuing development of a new generation of quiet commercial
USA supersonic aircraft and have also led to the newlexicon “sonic thump” that reflects
Email: their quieter sounds (explained in Unique Qualities of Sonic Booms). Low-frequency energy, the transient nature of the sound, and high-frequency
energy at shocks are qualities of sonic booms that differ from conventional
subsonic aircraft noise. Thus the noise metrics that are currently used for airport
noise ca.nnot be used for evaluation of community a.nnoyance and acceptance for
sonic booms. Although perceived level (PL; Stevens, 1972) has been identified as a
preferred metric (Leatherwood et al., 2002) for describing sonic boom annoyance
in outdoor environments, there is no internationally agreed on standard noise
metric that can be used to quantify the sonic boom level.
Data gathered from planned future community tests with a supersonic demonstrator
aircraft will be provided to regulatory organizations such as the International Civil
Aviation Organization (ICAO) to provide the scientific basis for development of
new noise certification standards for supersonic aircraft. Today’s research will help
prepare for this future community testing to ensure gathering of accurate data in an
eflicient manner.
Unique Gualitiee of Sonic Bunnie
The transient nature of the sonic boom and large amount of low-frequency
energy in the signal result in a sound character that is perceived much differently
volume 14, 1551493 [ Fall 2013 | Accuslzlcl Tnday | ea

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