Multipath Interpretation of Secondary Sonic Boom Signatures

This paper reports on the rediscovery of one aspect of secondary sonic booms from supersonic aircraft that were originally brought forward by Edward Rickley and Allan Pierce. The phenomenon explains why secondary sonic booms often have a longer duration than one would expect. The term rediscovery is used since the ideas are not new, since Rickley, Pierce, and others knew about, or at least suspected, this phenomenon previously. The current paper brings back this old hypothesis and reports on preliminary simulations that support the ideas Rickley and Pierce put forward. The evidence shows that secondary sonic booms have longer durations because secondary sonic boom signatures are comprised of multiple arrivals along multiple source and propagation paths, whereas primary carpet sonic boom signatures usually arrive along a single ray.