>>1099482

"The GE-90 has a fan diameter of 3124 mm and a rotational speed of 3475 RPM. Their circumferential velocity is d·π·57.917 = 568 m/s or Mach 1.67 at sea level and ISO atmosphere."

https:// aviation.stackexchange.com/questions/22316/why-do-turbofan-blade-tips-exceed-the-speed-of-sound-while-prop-tips-should-not

>>1100063

This circumferential velocity of Mach 1.67 is perpendicular to the direction of travel of the aircraft.

>>1099589

USGS performs a valuable service to the nation. Defunding isn't the answer. Cleaning house would be the way to go, IMO.