A model of interior cockpit noise for the F-35A

Abstract

Characterization of environmental noise is vital to protection of hearing. A measurement campaign to understand the nature of the noise in the cockpit of fifth-generation fighter aircraft has been completed. Measurements during multiple missions for each variant of the F-35 aircraft characterized the cockpit acoustic levels during various stages of flight. Additional data collection defined the aircraft state during the acoustic data collection. An initial model of the F-35A represents the A-weighted overall sound pressure level (LA) within the cockpit by a series of random decision forest models. Sensitivity analysis conducted on these models demonstrates that airspeed and the environmental control system (ECS) flow rate are the two most important parameters determining the interior acoustic levels. However, the measurements cover a subset of the full dynamic envelope of the aircraft. Since machine-learning algorithms are susceptible to greater uncertainty where no acoustic data exists, a curve fit model defines acoustic levels throughout the envelope. This model adds the ECS flow rate to the dynamic pressure calculations and produces a more accurate model of LA within the cockpit of the F-35A. This research is sponsored, in part, by F-35 Joint Program Office.