A loud "Yippee" was heard over the radio, as Joe Walker landed the X-15. It was August 4, 1960, and he had just flown the experimental aircraft nearly 2,200 mph. This was only Walker's fourth flight in the rocketplane. His previous flight marked the first time anyone had broken Mach 3 and survived, yet this flight was special for him in that it had taken four attempts to fly. Three airborne aborts and nearly two months of weather delays had gotten Joe anxious to complete another successful flight.

He had nothing to worry about on this program, as he would be considered the most successful of the twelve pilots that flew this rocket research aircraft at speeds and altitudes no one had ever flown before. Walker went on to fly the X-15 to an unofficial speed record of 4,104 mph on June 27, 1962, and on August 22, 1963, reached an unofficial altitude record of 354,200 feet, proving once again that a winged-aircraft could be flown into space and landed safely. This flight also marked Walker as the first ever civilian to fly into space. He had twice before flown past the 50-mile altitude, recognized at that time as a the demarcation to outer space; however, this one flight, taking him 67 miles above the Earth, was the only time in the X-15 program a pilot flew above 100 kilometers, now the internationally-recognized limit for astronaut status.

Joe Walker was born February 20, 1921, and raised on a farm in Washington, Pennsylvania. He learned at an early age to work hard to achieve goals, and developed a thirst for knowledge. He began elementary school where several grades shared one room in the schoolhouse. The teacher would instruct one age group while the others would work on their assignments. It wasn't unusual for Walker to complete his assignments and join in on the discussions of a higher grade. Joe was mechanically inclined, too. As an early teen, he took an old farm motor and an old buggy and built a scooter. He got the thing to run, but, he forgot to incorporate brakes!

He graduated high school fourth in his class, and won a scholarship to Washington and Jefferson College in the fall of 1938. While in college, Joe taught physics, worked as a lab assistant and, of course, worked on the farm. During his senior year, he enrolled in the Civilian Pilot Training Program. The instructor told him he'd never be a pilot because he was too cautious. But Joe toughed it out, and when he took the aviation cadet examination, he made the highest score of any aviation cadet in the Pittsburgh area. Joe graduated from Washington and Jefferson with a B.A. in physics and went on to join the Army Air Force in 1942. He flew 58 missions between 1943 and 1944 as a photo reconnaissance pilot in a modified P-38 Lightning fighter. Recon pilots had to depend heavily on their flying skills, as they weren't equipped with much armament. This was great training for his next profession as a test pilot.

After the war, Joe began working as a physicist with the National Advisory Committee on Aeronautics (NACA, the precursor organization to present day NASA) in Cleveland, Ohio. However, when he heard a familiar sound--a P-38 firing up--it didn't take long for him to be back flying again. His research flights dealt mainly with aircraft icing both in the wind tunnel as well as in flight. In 1951, Joe had a chance to transfer to NACA's High Speed Flight Station at Edwards AFB, California--and he took it. Just four years earlier, the X-1 had broken the sound barrier, and Edwards was a hotbed of aeronautical research. He began flying the B-29 mothership and then went on to fly some of the hottest X-planes available in the NACA hangars. Among them were the D-558-I, D-558-II, X-1A, X-3, X-4, and X-5. He was also involved in research projects with the F-100, F-101, F-102, F-104, and B-47.

On a flight in the X-3 Stiletto, when Walker made an abrupt roll to the left, the aircraft suddenly began to pitch and yaw. He had just experienced his first encounter with inertial coupling. He managed to get the X-3 under control and tried the maneuver again, this time in a dive. The X-3 suddenly pitched downward and then abruptly pitched upward. Walker was able to regain control of the aircraft and landed promptly. The X-3 was instrumental in unlocking some of the mysteries of the phenomena known as roll coupling.

Joe Walker is remembered most for his work with the X-15. The X-15 was the most successful X-plane ever built, paving the way for the space shuttle, as well as gathering valuable information for the Mercury, Gemini, and Apollo projects. It flew higher and faster than any other winged aircraft, and during the early 1960s, Walker was NASA's Chief Test Pilot for the X-15. It wasn't records that interested him, but the information that could be gleaned from every flight. Walker was a promoter of winged space-flight and was involved in the X-15 program since its inception. He helped solve design problems in the X-15 program from a pilot's point of view using his experience on previous research flights. As an advocate for better pilot instrumentation, Walker continually worked with the technicians to improve the instrument display, giving the pilot essential data required for reentry into the atmosphere and safe landings.

Walker worked to develop the reaction control system (RCS) used to adjust the attitude of the X-15 while in the upper portion of the atmosphere where the dynamic pressure is so low that conventional flight controls such as flaps, ailerons, or speed brakes are useless. Testing of the hydrogen peroxide-fueled RCS was done with the small rocket nozzles installed in the wings and nose of a modified F-104. Walker climbed into the JF-104 one morning and smelled hot peroxide. He immediately climbed out of the aircraft just before the H2SO4 tank, located right behind the cockpit, exploded.

Joe Walker left the X-15 program after 25 flights between March 25, 1960, and August 22, 1963, and then moved on to other challenges at NASA. He was the first to pilot the Lunar Landing Research Vehicle (LLRV) which led to the development of the Lunar Landing Training Vehicle (LLTV) used by astronauts like Neil Armstrong before they landed on the Moon. After leaving the LLRV project, he moved on to the XB-70 triple-sonic bomber research project. During this time, he still served as chase pilot for various test programs and continued to travel across the country giving presentations on the X-15 and other research projects in progress at the NASA Flight Research Center (now known as Dryden Flight Research Center).

Walker was scheduled to make his first flight in the XB-70 on June 9, 1966. However, on the morning of June 8, he was flying chase to an XB-70 sonic boom test mission. After the flight tests were completed, several aircraft joined them in a photo opportunity for General Electric, who had manufactured the jet engines used in all the aircraft. They wanted photos for their corporate brochure for an upcoming stockholder's meeting. The in-flight photographers urged the pilots to tighten the formation for better photos. Due to the unique configuration of the XB-70, a wingtip vortex caught Walker's plane and the F-104N was cartwheeled over on top of the bomber, instantly killing Walker as his plane came apart and severed the tails from the bomber. XB-70 pilot Al White (backup pilot from North American Aviation on the X-15 program) was able to eject, but Major Carl Cross was unable to operate the ejection system and went down with the plane. Joseph A. Walker, an aviation icon was gone.

Walker received many awards for his life's achievements, which included the Air Medal with seven Oak Leaf Clusters, Distinguished Flying Cross, Octave Chanute Award, Iven C. Kincheloe Award, American Airlines Admiral of the Flagship Fleet Award, Harmon International Trophy for Aviators, Robert J. Collier Award, David C. Schilling Award, and the National Pilots Association's Pilot of the Year. His alma mater awarded him an honorary doctorate degree in Aeronautical Sciences, and there's even a crater on the Moon named after him! His family was awarded posthumous astronaut wings in a ceremony at the Dryden Flight Research Center, August 23, 2005, this was 42 years and one day after his last X-15 flight. 

Forty years after his death, some aviation enthusiasts have banded together to create the Joseph A. Walker Memorial Fund. The main goals of the Fund are two-fold: 1) to preserve our nation's historical experimental aircraft; and 2) to give financial support to send a student and faculty staff member from Joseph A. Walker Middle School in Quartz Hill, California, to a session of Space Camp each summer.

Other goals of the fund include: 1) placement of a plaque honoring Joe Walker and USAF Major Carl Cross at the F-104N/XB-70 crash site about 10 miles outside Barstow, California; 2) development of a partnership between the Joe Walker Middle School and a school from his home-town of Washington, Pennsylvania; 3) placement of a model of the X-15 on the grounds of the Joe Walker Middle School; and 4) a yearly celebration of Joe Walker's life and achievements

On June 8, 2006, a large white cross was erected at the site where the fuselage of Walker's F-104 came to rest on the desert floor exactly 40 years previously. Several aviation enthusiasts from the X-Hunters organization, Joe Walker's son Jim, and members of the Orange County Space Society were on hand to pay their respects to Joe Walker and Major Carl Cross, heroes of aviation history that helped pave our way to the stars.

NOTE: The views of this article are the author's and do not reflect the policies of the National Space Society.

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