There is some historical precedent, based on available scientific data, for sonic booms caused by aircraft correlating with mystery boom reports. These sonic booms may become audible over inland areas where, ordinarily, they would never be heard, when accompanied with unusual weather phenomenon.
Between 1977 and 1978, more than 600 reports of mystery booms were reported along the east coast of the United States, particularly between the regions of New Jersey and Nova Scotia. The frequency of reports around that time led to speculation about whether weapons tests might be underway, or if supersonic aircraft might be to blame; particularly with regard to reports of mystery booms heard over the Canadian coast.
Jeremy Stone, former president of the Federation of American Scientists, concluded that many of the booms reported during the late 1970s were the result of flight paths made by the Concorde, a turbojet-powered supersonic passenger jet airliner, which remained in service between 1976 and 2003. (1) The Concorde aircraft were forbidden to fly over land due to the sounds that resulted from their speeds; however, on particularly hot days, fuel carried within the jets would expand, reducing the amount of fuel capacity within the tanks. Therefore, Concorde pilots had routinely been making shortcuts over Nova Scotia in order to compensate for the fuel inefficiency associated with warmer days.
Meteorologist Richard Wood with the U.S. Weather Service in Tucson went on to supplement this data with his own study of atmospheric phenomena. Wood suggested that “an unusual snakelike configuration” of the jet stream coincided with days where a prevalence of boom reports had been catalogued. In particular, a mysterious boom reported around Charleston, SC that year had coincided with the jet stream blowing due north, which effectively carried supersonic booms of offshore aircraft further inland. (1)
Despite Wood’s appraisal, Gordon MacDonald disagreed that the former’s conclusions explained all of the “mystery booms.” A report that followed, written by MacDonald, concluded that only 413 of the 594 incidents could be directly linked with known supersonic aircraft; it was MacDonald’s opinion that perhaps a majority of the remaining 181 events “had a natural origin.” (1)
More recently, the theories about sonic booms from aircraft were revived, following press in the UK that detailed comparisons between mystery booms heard over parts of the UK and the US, and certain hypersonic jet engines which may be used by experimental aircraft. The Mail Online cited Dr Bhupendra Khandelwa, an engineering expert and authority on such craft, who believed the volume and repetition discernible in recordings of the “mystery booms” over the UK “sounded like an experimental jet engine called a pulse detonation engine (PDE).” (2) Numerous sites had previously written about what were believed to be experimental stealth aircraft that were photographed over Texas and Kansas in the early months of 2014 (for an expansive article on these aircraft, and various speculation about them, see this link).
For more information on the history of “mystery” aircraft, visit the Federation of American Scientist’s Intelligence Resource Program page on the subject here.
- Stone, Jeremy. Every Man Should Try: Adventures of a Public Interest Activist. Public Affairs, Perseus Books Group. 1999. Chapter 17, “Booms and Earthquakes: Saving the East Coast a Scare”: http://catalytic-diplomacy.org/everymanPDFs/Ch17.pdf
- “Is this proof mysterious bangs heard on both sides of Atlantic WERE caused by a top-secret US jet? Footage of hypersonic engine in action reveals it sounds almost identical to unexplained noises.” Daily Mail, http://www.dailymail.co.uk/sciencetech/article-2855802/Is-proof-mysterious-bangs-heard-sides-Atlantic-caused-secret-jet-Footage-hypersonic-engine-action-reveals-sounds-identical-unexplained-noises.html