# Learjet 722 Bravo Delta Crash: Mach Tuck and Possible Tail Breakup - Original post: https://www.twitter.com/i/status/2117744297332363294 - Source account: [@JG_CSTT](https://x.com/JG_CSTT) - Source language: English - Duration: 2:59 - Published: 2026-11-06 - Canonical URL: https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup ## Transcript [0:00](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup) Declare emergency, 722 Bravo Delta. We are in an overspeed condition, descending 20,000 feet per minute. [0:07](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup?t=7) Overspeed. That's what the crew of Learjet 722 Bravo Delta radioed as they fell from 35,000 feet. [0:15](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup?t=15) 75 seconds later, it crashed, killing all nine people on board. [0:20](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup?t=20) Did a Mach tuck bring it down? [0:24](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup?t=24) Mach is speed compared to the speed of sound. [0:27](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup?t=27) Air flowing over the top of a wing moves faster than the air underneath. [0:32](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup?t=32) Faster air has lower pressure, so the higher pressure below pushes the wing up. [0:37](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup?t=37) That's lift. But go fast enough and the air on top goes supersonic and a shock wave forms. [0:44](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup?t=44) As speed builds, the shock slides back and the lift slides back with it behind the center of gravity. [0:51](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup?t=51) The nose drops, the jet speeds up, and the nose drops more. [0:55](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup?t=55) That's a Mach tuck. The Learjet 60 cruises close to that edge. [1:00](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup?t=60) Its limit is Mach.81, and before the upset, this jet was at about .75. [1:07](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup?t=67) Learjets carry a Mach trim system that raises the nose automatically as speed builds. [1:13](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup?t=73) Hand flying without it, the 60's limit drops to .77, and in 1980, the NTSB warned that once earlier Learjets got into a fast, steep dive, recovery may be impossible. [1:26](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup?t=86) Here's the transponder data. The crew reported ice and turbulence and asked to climb. [1:31](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup?t=91) Then the nose went down, wings level. In 13 seconds, the jet blew through its Mach limit and kept going past Mach .9. [1:40](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup?t=100) Then it rolled into a steep right spiral where pulling back only tightens the turn. [1:46](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup?t=106) We are descending 22,000 feet and we are banking 60 degrees. [1:53](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup?t=113) Could that tear off the tail? The physics say yes. [1:56](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup?t=116) By 9,000 feet, it was doing almost 500 knots against a limit of 340. [2:02](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup?t=122) That's twice the air pressure on every surface. [2:06](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup?t=126) Pushed that far, a tail can flutter and shake itself apart, or the pull to recover can snap it. [2:12](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup?t=132) In 1985, a China Airlines 747 dove 30,000 feet and the pullout tore away pieces of its tail. [2:21](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup?t=141) The NTSB says there's some evidence of a breakup before impact, and the dash cam appears to show the jet without its horizontal tail. [2:29](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup?t=149) Which came first? A jet that loses its tail tumbles and slows down. [2:34](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup?t=154) This one kept flying a smooth, tightening spiral, its airspeed still climbing down to 9,000 feet. [2:41](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup?t=161) So if the tail came off, it most likely came off late, torn away by the dive. [2:47](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup?t=167) What started the upset is still unknown. [2:49](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup?t=169) Where the tail pieces landed will tell investigators when they came off. [2:54](https://www.translate.mom/transcript/HVsUPmjB3Q4f/en/learjet-722-bravo-delta-crash-mach-tuck-and-possible-tail-breakup?t=174) Until then, the precise cause of the crash remains unknown.