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The Boeing 2707 SST program of the 1960's was very ambitious, aiming for 300 passenger aircraft flying at speeds of Mach 2.5 to 3.

The similarly sized XB-70 was test flown supersonicly along a potential commercial route over land, producing "numerous complaints of cracked glass and broken plaster". Rising fuel prices and political opposition canceled the program before prototypes could be completed.

What would the mathematical relationship be between the intensity of a sonic boom (of the same aircraft at the same altitude) at Mach 1.5 vs 3.0?

Would it be 1/2, 1/4, or be predictable at all?

What would be the sonic boom relationship be if a smaller scale version of 1/2 it's mass flew at the same Mach and altitude?

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  • $\begingroup$ I had not heard of a test along a commercial route. Sonic boom tests I know of that "targeted" civilians were the 1961 St. Louis tests using B-58 and F-106, and the 1964 Oklahoma City tests using B-58, F-106, F-104, and F-101. The 1964 test resulted in public complaints and negative publicity for the SST program. In 1966 the XB-70 conducted test flights at Dryden as part of the National Sonic Boom Program, according to the Dryden website these tests targeted instrumented buildings as well as "100 test personnel". $\endgroup$ Feb 12 at 20:06

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A larger and heavier aircraft must displace more air and create more lift to sustain flight, compared with small, light aircraft. Therefore, they will create sonic booms stronger and louder than those of smaller, lighter aircraft. The larger and heavier the aircraft, the stronger the shock waves will be.

Source: NASA Facts, Dryden Flight Research Center

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    $\begingroup$ Since the question asks for a mathematical relationship, you might want to add that sonic boom strength grows with the inverse of distance squared and linearly with airplane weight. $\endgroup$ Feb 12 at 18:57
  • $\begingroup$ @PeterKämpf thanks! Do you think designing an aircraft asymmetricly like the BV 141 might cause a more diffuse supersonic shock wave? $\endgroup$ Feb 12 at 19:43
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    $\begingroup$ Airplane shape has no bearing on it whatsoever? $\endgroup$
    – Sixtyfive
    Feb 12 at 20:29
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    $\begingroup$ @Sixtyfive It does! Slender aircraft cause weaker booms than blunt aircraft. Just look how long the tip of the X-59 is! But it is harder to express that in a simple mathematical relationship. $\endgroup$ Feb 13 at 9:25
  • $\begingroup$ @RobertDiGiovanni Interesting idea! I think a slender Sears-Haak-body will yield the best results, and asymmetry will not help. But that is just me guessing ... $\endgroup$ Feb 13 at 9:28

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