No supersonic boom for dinosaur tails

[Still Waters]

Diplodocids—large herbivorous dinosaurs with long necks and tails—may have been able to move their tails like bullwhips at speeds of up to 33 meters per second (more than 100 kilometers per hour), according to a modeling study published in Scientific Reports. However, these findings contradict those of a previous study, which proposed that a hypothetical structure attached to the end of a diplodocid tail—similar to a tuft at the end of a bullwhip—could move faster than the speed of sound (340 meters per second) and create a small supersonic boom.

Simone Conti and colleagues simulated diplodocid tail movements using a model based on five fossilized diplodocid specimens. The model tail is over 12 meters long, weighs 1,446 kilograms and consists of 82 cylinders—representing vertebrae—attached to an unmovable hip bone base. When the tail base moves in an arc, it generates a whip-like movement with a maximum speed of 33 meters per second—more than ten times slower than the speed of sound in standard air and too slow to create a supersonic boom.

https://phys.org/news/2022-12-paleontology-supersonic-boom-dinosaur-tails.html

https://www.nature.com/articles/s41598-022-21633-2