This is a bit off the topic of the thread, but....
From
http://en.wikipedia.org/wiki/Sound_barrier: “ Hans Guido Mutke claimed to have broken the sound barrier on April 9, 1945 in a Messerschmitt Me 262. However, this claim is disputed by most experts and lacks a scientific foundation.
George Welch apparently broke the sound barrier on October 1, 1947 while diving the subsonic XP-86 Sabre. 14 days later, 30 minutes before Yeager's historic flight, Welch apparently repeated his supersonic flight. Although evidence from witnesses and instruments strongly imply that Welch achieved supersonic speed, the flights were not properly monitored and cannot be officially recognized. (The XP-86 officially achieved supersonic speed on April 26, 1948.)
Chuck Yeager (then a Major in the US Air Force, later a Brigadier General, promoted in 2005, 30 years after his official retirement, to Major General) was the first person to break the sound barrier in level flight on October 14, 1947, flying the experimental Bell X-1 at Mach 1 at an altitude of 45,000 feet in a rocket. Yeager's flight was part of a test program with the goal of achieving supersonic flight so proper monitoring was in-place for the flight.
Chuck Yeager is officially credited with being the first person to break the sound barrier "in level flight" (see the video below). This leaves the door open for claims of previous supersonic flights made while diving.”
From
http://history.nasa.gov/x1/chuck.html: “On October 14, 1947, Yeager broke the sound barrier over the town of Victorville, California.”
From
http://www.who2.com/chuckyeager.html: “Chuck Yeager was the first human to fly faster than the speed of sound. A combat pilot in World War II, Yeager was shot down over France in 1943, but managed to escape without being captured. After the war he was put in charge of pilot training for experimental aircraft, and on October 14, 1947 became the first person to break the sound barrier, flying a rocket powered Bell X-1 jet.”
From
http://history.nasa.gov/x1/chuck.html: “On October 14, 1947, Yeager broke the sound barrier over the town of Victorville, California.”
From
http://www.popularmechanics.com/science/aviation/1280546.html?page=1&c=y: “Editor's Note: This article originally ran in our November 1987 issue. It was the 40th anniversary of the day Gen. Yeager climbed into the Bell X-1 and became the first man to travel faster than the speed of sound.”
