The noise dose range of the X-59 estimated from propagation simulations

Abstract

NASA’s X-59 aircraft will soon be flown in a series of low-boom community noise surveys across the USA. Community test experimental designs will include noise dose schedules, which require an estimate of the noise dose range that X-59 can produce. To determine the dose range, propagation simulations using NASA’s PCBoom code were completed using CFD-generated X-59 C612A near-field pressure data for an on-design condition (Mach 1.4 at 53 200 ft) and two off-design conditions (Mach 1.4 at 46 000 ft and Mach 1.3 at 43 000 ft). Near-field data at four cardinal aircraft headings were propagated through one year of realistic atmospheric profiles from the Climate Forecast System Version 2 database at several USA locations. Statistics of the mean and range of the Perceived Level (PL) of the booms in the inner 40 km of each carpet as well as the carpet width were computed. Results indicate the typical inner carpet mean PL is approximately 70–87dB depending on the aircraft condition. The typical PL range across the inner carpet is 6–8 dB (on-design) and 5–13 dB (off-designs). The carpet widths ranged from 32–55 km. Understanding these quantities for various flight and atmospheric conditions is important for planning X-59 community noise surveys.