For an Advanced SST the quote near the end is, "Advances in aircraft technology suggest that sonic boom amplitudes for this type of aircraft, also referred to a

For an Advanced SST the quote near the end is, "Advances in aircraft technology suggest that sonic boom amplitudes for this type of aircraft, also referred to as a High Speed Civil Transport (HSCTJ or the "Orient Express". could be made substantially lower than first generation SSTs. potentially to the point that overland flight could be acceptable." I'm not sure what to make of Fig. 10. I'm sure they are accurately plotting their equations, but the impulse for the SST is a minimum at 50,000 feet and increases for higher altitudes altitudes. The impulse for the HST generally increases with altitude. OTOH they discuss the N-wave forming in the far field and maintaining its shape, but also broadening which seems like it would reduce the impulse just like the overpressure. The references 31-33 have alot of data. Here is a link to the first one: https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19640014910.pdf https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/196400... PS - If you are getting three digits of accuracy eyeballing Fig. 10, you must have gotten a much cleaner copy than I did. ;)