Abstract by Aaron Vaughn
Physics and Astronomy
On the possibility of Mach reflections in shock-containing noise near tactical aircraft
Ground-based measurements near a tactical aircraft show greater than pressure doubling for shock events, when compared to nearby microphones off the ground. A possible explanation for this phenomenon is the occurrence of irregular (Mach) reflections of the shock waves at the ground. Two-point cross correlation of windowed shock events from adjacent microphones are used to estimate the source location of the shock events and the corresponding angle of incidence to the ground. The combined angle of incidence with the measured shock pressure rises show that Mach reflections are likely. The associated pressure increase at the shocks appears to enhance shock-related metrics, such as the skewness of the pressure time-derivative, relative to microphones off the ground.