Underwater positioning study of flight recorder

A flight recorder, which is also called the “black box,” is installed on each airplane, and it records the process of every flight. If the airplane crashes into water, the underwater locater beacon (ULB) of the flight recorder will be activated and emit ultrasonic sound at 37.5 kHz for 30 days. We propose using underwater acoustic detection simulation to enhance the search process by identifying the location with acoustic data assimilation and transmission loss simulation. The ULB of NA-706 Black Hawk Helicopter in the tragedy in February 2018 was salvaged successfully, and the location was close to the estimated location based on the scheme of the acoustic data assimilation and transmission loss simulation proposed in this paper. Aircraft manufactured from now on must be equipped with an 8.8 kHz flight recorder. This study compares the detection ranges of these two types of flight recorders. It can be found that the detection range of the 8.8 kHz recorder is greater. This is helpful to reduce the time required for search and rescue. © ICTCA2019 14th International Conference on Theoretical and Computational Acoustics.