Underwater acoustic measurements with a flying wing glider

Abstract

Liberdade, a new class of underwater glider based on a flying wing design, has been under development for the past 3 years in a joint project between the Marine Physical Laboratory, Scripps Institution of Oceanography and the Applied Physics Laboratory, University of Washington. This hydrodynamically efficient design maximizes the horizontal distance traveled between changes in buoyancy, thereby minimizing average power consumed in horizontal transport to achieve ‘‘persistence.’’ The first fully autonomous glider of this class, ‘‘XRay,’’ was deployed and operated successfully in the Monterey Bay 2006 experiment. Communications, including real-time glider status reports, were accomplished using an underwater acoustic modem as well as with an Iridium satellite system while on the surface. The payload included hydrophone array, with 10 kHz per channel bandwidth, located in a sonar dome along the leading edge of the 6.1-m-span wing. Narrowband tones from 3.0 to 8.5 kHz were transmitted from a ship-deployed controlled underwater source. During the glider’s flight, lift-to-drag ratios (equal to the inverse of the glide slope) exceeded 10/1. However, specific flight behaviors that deviated from this efficient horizontal transport mode allowed for improved detection and localization by the hydrophone array. [Work sponsored by the Office of Naval Research.]

Oceanic Wave Glider Overview; Development and Applications

“…The glider is very quiet, making it hard to detect using passive acoustic sensing. The XRay glider is hoped to achieve 1-3 knot cruise speeds, have a 1200-1500 km range, and be able to remain on-station up to 6 months in partial buoyant glides [35].…”

Hydroacoustic equipment of autonomous underwater profilers

“…АНПА оснащают акустическим доплеровским профилографом течений (ADCP) для проведения измерений по маршруту движения. Для гидроакустического мониторинга наиболее приспособлены глайдеры, бесшумно планирующие под водой (D'Spain et al, 2005;D'Spain et al, 2007;D'Spain et al, 2007). Планер глайдера X-Ray имеет широкие крылья, несущие решетки гидроакустических антенн.…”

Flying wing underwater glider: Design, analysis, and performance prediction

“…Jenkins [4]. To further study the influence of Flying Wing shape on the lift-drag ratio, we developed an underwater glider (HFWUG) based on the configuration design.…”