From http://www.findagrave.com/cgi-bin/fg.cgi?page=gr&GRid=78273160

Birth:  Apr. 9, 1924
Buffalo
Wilson County
Kansas, USA
Death:  Sep. 27, 1956
California, USA

Milburn G. "Mel" Apt

He was a US test pilot. He was killed in the destruction of the Bell X-2 during a test flight.
After having been launched from a B-50 bomber over the Mojave Desert in California, Capt. Milburn G. Apt (USAF), flying an X-2 rocket-powered plane on its 13th powered flight, set a record speed of 3,377 km/h, or Mach 3.196 at 19,977 m (65,541 ft). Subsequent loss of control from inertia coupling led to the breakup of the aircraft and the death of the pilot. The X-2, initially an Air Force program, was scheduled to be transferred to the civilian National Advisory Committee for Aeronautics (NACA) for scientific research. The Air Force delayed turning the aircraft over to the NACA in the hope of attaining Mach 3 in the airplane. The service requested and received a two-month extension to qualify another Air Force test pilot, Capt. Milburn "Mel" Apt, in the X-2 and attempt to exceed Mach 3. In the run-up to his first rocket-plane flight, Apt had several ground briefings in the simulator. His simulator training had indicated control difficulties in high-speed flight, and possible techniques for handling them. On 27 September 1956, Apt made his first X-2 flight. Apt raced away from the B-50 under full power, quickly outdistancing the F-100 chase planes. At high altitude, he nosed over, accelerating rapidly. At 65,000 feet, the X-2 reached Mach 3.2 (2,094 mph), making Apt the first man to fly more than three times the speed of sound. Upon rocket burnout, Apt found himself further from home than anticipated. The planned flight profile called for slowing to Mach 2.4 before turning back to base. The additional time to slow before turning may have put him beyond safe gliding range of his planned runway. Still above Mach 3, he began a turn back to Edwards. The X-2 began a series of diverging rolls and tumbled out of control. Apt tried to regain control of the aircraft. Unable to do so, Apt separated the escape capsule. Too late, he attempted to bail out and was killed when the capsule hit the Edwards bombing range. The rest of the X-2 crashed five miles away. Apt earned a B.S. in Engineering Sciences from the Air Force Institute of Technology in 1951.
 
Burial:
Buffalo Cemetery
Buffalo
Wilson County
Kansas, USA

See also https://en.wikipedia.org/wiki/Milburn_G._Apt