mrob already provided you with an answer. There's some more info here: https://en.wikipedia.org/wiki/Supersonic_transport#History https://en.wikipedia.org/wiki/

mrob already provided you with an answer. There's some more info here: https://en.wikipedia.org/wiki/Supersonic_transport#History https://en.wikipedia.org/wiki/Supersonic_transport#History I thought it was common knowledge. We learned about ozone layer hazards (and SST was among the most destructive ones) in elementary school (7th or 8th grade, Europe) when we learned about ozone layer.