"The Boeing Co. 737-800 was knifing through the air at more than 640 miles (966 kilometers) per hour, and at times may have exceeded 700 mph, according to data from Flightradar24, a website that tracks planes.
"The preliminary data indicate it was near the speed of sound," said John Hansman, a Massachusetts Institute of Technology astronautics and aeronautics professor who reviewed Bloomberg's calculation of the jet's speed. "It was coming down steep.""
"China Plane Was Travelling At Speed Of Sound As It Slammed Into Hill":
https://www.ndtv.com/world-news/china-jets-fatal-dive-took-i...
"The Boeing Co. 737-800 was knifing through the air at more than 640 miles (966 kilometers) per hour, and at times may have exceeded 700 mph, according to data from Flightradar24, a website that tracks planes.
"The preliminary data indicate it was near the speed of sound," said John Hansman, a Massachusetts Institute of Technology astronautics and aeronautics professor who reviewed Bloomberg's calculation of the jet's speed. "It was coming down steep.""