In the annals of experimental aircraft, the X-15 is not as revered or as remembered as the Bell X-1, which had the distinction of being the first plane to break the sound barrier. This is the case even though the X-15 still holds the record for the fastest speed by a manned aircraft and for the highest-flying manned aircraft, with no competitors in sight, despite its last flight taking place on Oct. 24, 1968. Authors John Anderson and Richard Passman’s X-15: The World’s Fastest Rocket Plane and the Pilots Who Ushered in the Space Age lays out the case for why the X-15 was and continues to be such an important aircraft.
Authors John Anderson and Richard Passman’s X-15: The World’s Fastest Rocket Plane and the Pilots Who Ushered in the Space Age lays out the case for why the X-15 was and continues to be such an important aircraft.
Anderson and Passman’s love affair with the X-15 is no surprise, given their involvement with the National Air and Space Museum in Washington, D.C. Anderson currently serves as the curator for aerodynamics, while Passman is a volunteer historian. In fact, the book is envisioned as a companion book for the X-15 on display at the National Air and Space Museum. X-15 delivers a short, concise history of the plane’s 199 flights and of those who flew them. Of the three X-15s built by North American, besides the one hanging at the National Air and Space Museum, one is on display at the National Museum of the U.S. Air Force. The third aircraft was destroyed in a crash on Nov. 15, 1967, that killed test pilot Michael Adams.
X-15: The World’s Fastest Rocket Plane and the Pilots Who Ushered in the Space Age, by John Anderson and Richard Passman; Zenith Press; 144 pages
Much of X-15 is made up of sometimes dense technical details that explain how the aerodynamic properties of the aircraft enabled it to fly so fast and so high – Mach 6.7 and 354,200 feet respectively. Interestingly for a Cold War program, the X-15 and its flights were unclassified. The authors succeed in explaining the technical details in a way that even a lay reader can understand. Sidebars with brief explanations on subjects such as monocoque construction, ablative coating, the air data inertial reference unit (ASIRU), and lifting bodies, are also helpful tools in understanding some of the complex technical details.
One North American Aviation pilot, five Air Force officers, one Navy officer, and five NASA pilots set records in the cockpit of the X-15. This group includes Neil Armstrong, the first man on the Moon, who made seven flights in the X-15.
Some of the most compelling reading in the book consists of the stories of the 12 pilots who flew the X-15. Befitting a joint program made up of contributions from the U.S. Air Force, NASA, and the U.S. Navy, the pilots made up a diverse group. One North American Aviation pilot, five Air Force officers, one Navy officer, and five NASA pilots set records in the cockpit of the X-15. This group includes Neil Armstrong, the first man on the Moon, who made seven flights in the X-15. Eight of the pilots earned astronaut wings for taking the X-15 above 50 miles, although the three civilian NASA pilots who achieved the feat had to wait until Aug. 23, 2005, to receive their wings.
X-15 pilots. From left to right: U.S. Air Force Capt. Joseph H. Engle, Air Force Maj. Robert A. Rushworth, NASA pilot John B. “Jack” McKay, Air Force pilot William J. “Pete” Knight, NASA pilot Milton O. Thompson, and NASA pilot Bill Dana. Of their 125 X-15 flights, 8 were above the 50 miles that constituted the Air Force’s definition of the beginning of space (Engle 3, Dana 2, Rushworth, Knight, and McKay one each). NASA photo
Another area where X-15 excels is in its generous use of photography. Although the dimensions of the book preclude it from being labeled a coffee table book, X-15 is filled with hundreds of photos. The photos, many of them in color, show every conceivable part of the X-15 program. From launch preparations, to flight, to landing, it’s all there.
One area where X-15 could have greatly benefited might have been in a more complete telling about why the X-15 program was so important, and in how lessons learned from the program were applied to future aircraft and spaceship design. The authors seems to assume that its obvious to the reader that the X-15 contributed directly to the Space Shuttle or that it being air-launched from a B-52 Stratofortress was the genesis of the private SpaceShipOne and SpaceShipTwo.
Followed by a Lockheed F-104A Starfighter chase plane, the North American X-15 ship #3 (56-6672) sinks toward touchdown on Rogers Dry Lake, Calif., following a research flight. In the foreground is green smoke, used to indicate wind direction. The F-104 chase pilot joined up with the X-15 as it glided to the landing. The chase pilot was there to warn the X-15 pilot of any problems and to call out the altitude above the lakebed. F-104 aircraft were also used for X-15 pilot training to simulate the landing characteristics of the rocket-powered airplane, which landed without engine power since the rocket engine had already burned all of its propellant before the landing. The F-104s could simulate the steep descent of the X-15 as it glided to a landing. They did this by extending the landing gear and speed brakes while setting the throttle to idle. NASA photo
The contributions of the X-15 and its pilots are still being studied and used today to plan the future of aviation. This book makes the reader want to visit the National Air and Space Museum and view the X-15 up-close in a whole new light, in which its aerospace accomplishments rank alongside other distinguished aircraft on display at the museum such as the Douglas World Cruiser “Chicago,” “Spirit of St. Louis,” and Bell X-1.