Crossfield was the first of twelve pilots who flew the North American X-15, an experimental spaceplane jointly operated by the United States Air Force and NASA.

Crossfield graduated from Boistfort High School southwest of Chehalis, attended the University of Washington in Seattle, then worked for Boeing.

In later years, Crossfield often cited his curiosity about this solo spin anomaly and his desire to analyze what was going on and why it happened, as the start of his test pilot career.

With 99 flights in the rocket-powered X-1 and D-558-II, Crossfield had—by a wide margin—more experience with rocketplanes than any other pilot in the world by the time he left Edwards to join North American Aviation in 1955.

Crossfield was not only involved with the design of X-15 from the beginning, but introduced many innovations, including putting engine controls of the rocket plane into the cockpit.

Unable to jettison his propellants, Crossfield was forced to make an emergency landing during which the excessive load on the aircraft broke its back just behind the cockpit.

Once again he was uninjured as Dr. Toby Freedman, NAA Medical Director, pried open the cockpit to save him and despite being subjected to a later calculated acceleration force of near 50 Gs (although Crossfield stated in the Discovery Channel's series Frontiers of Flight that he began to have debilitating issues with his night vision after the accident) and the airplane was completely rebuilt.

In his remarks to a number of aviation groups, Crossfield cited the X-15 as one of few aircraft that caused grown men to cry upon its retirement.

In 2004, White Knight carried Space Ship One to its successful launch and winning of the Ansari X-Prize, the first attempt by a plane since the X-15 cancellation.

Crossfield co-authored Always Another Dawn, a story of a rocket test pilot, with Clay Blair Jr, and authored "Onward and Upward" Research Airplanes, Act II.

The training was successful, but the December 17, 2003 re-creation failed due to low engine power and the flyer's rain-soaked fabric covering which added considerably to its takeoff weight.

The Wright replica ultimately flew successfully at Kill Devil Hills, North Carolina after the Centennial jubilee but without media coverage.

On April 19, 2006, a Cessna 210A piloted by Crossfield was reported missing while flying from Prattville, Alabama toward Manassas, Virginia, near his home in Herndon.

[15] On April 20, authorities confirmed his body was found in the wreckage of his plane in a remote area of Ludville in Pickens County Georgia.

There were severe thunderstorms in the area when air traffic controllers lost radio and radar contact with Crossfield's plane.

[2] The Gordon County Sheriff's department reported that debris from Crossfield's aircraft was found in three different locations within a quarter mile,[16] suggesting that the plane broke up while it was still in the air.

On September 27, 2007, the National Transportation Safety Board issued a report stating the probable cause of his crash to be as follows: "The pilot's failure to obtain updated en route weather information, which resulted in his continued instrument flight into a widespread area of severe convective activity, and the air traffic controller's failure to provide adverse weather avoidance assistance, as required by Federal Aviation Administration directives, both of which led to the airplane's encounter with a severe thunderstorm and subsequent loss of control."

[citation needed] An elementary school was named in his honor near his last residence, in Herndon, Virginia (a community just northeast of Dulles International Airport).

[citation needed] He was also most proud of his A. Scott Crossfield Aerospace Education Teacher of the Year Award which is awarded annually at what is known as the "Oscar Night" in aviation, the Annual Enshrinement Ceremony Weekend at the National Aviation Hall of Fame held each year at the end of July in Dayton, Ohio.