The Cirrus stall-crash has resulted in related discussions about the relative safety of steep bank angles while descending. Paul says step bank angles can be made with relative impunity from stalls if descending. With due respect I join the dissenting side.
In November 1945, a British jet fighter the Gloster Meteor set a new official world speed record of 606.25 mph. It was two years later before the sound barrier was broken by an American aircraft the Bell X-1. Test pilot 'Chuck' Yeager named the aircraft 'Glamorous Glennis' after his wife.
If we take another look at the Mach 1 vs. altitude tables already discussed, we see that the speed of sound at 30,000 ft is 678.2 miles per hour. All we have to do is multiply this value by 3 to determine the speed of a vehicle traveling Mach 3 at 30,000 ft in miles per hour. The answer is 2,035 mph.