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    The Mojave Desert is home to Joshua trees, blistering sun, sandstorms and many bizarre-looking airplanes. The HL-10 qualifies as one of these strange desert birds that we love so much. She was the first Heavyweight Lifting Body to break the speed of sound and would go on to literally and figuratively change the shape of aerospace.

    She was delivered from Northrop to NASA Dryden Flight Research Center (now Armstrong) in January 1966 to join NASA’s fleet of Heavyweight Lifting Bodies, an idea fathered by R. Dale Reed in 1962. Reed realized that wings are not ideal for spaceflight because they are heavy, vulnerable and cumbersome at hypersonic reentry speeds. His idea was to create a reentry vehicle that had no wings, but could create enough lift from the fuselage alone to land on a conventional runway at relatively safe speeds. He imagined these vehicles as small personal spacecraft. This idea was embedded in the HL-10 name, standing for “Horizontal Landing”.

    The HL-10, along with other Heavyweight Lifting Bodies, had to be initially taken aloft to 45,000 feet by a B-52 mothership, then dropped into the wild blue yonder. The first drop was performed on December 22, 1966, piloted by Bruce Peterson. On this first flight, the HL-10 had no engine installed, so she simply glided back to a landing on Rogers Dry Lake adjacent to Dryden. The tenth flight, on September 24, 1968, included an XLR-11 rocket engine as part of the kit, but it wasn’t fired until the twelfth flight which took place on October 23, 1968. On this mission, the engine malfunctioned and Jerauld R. Gentry was forced to land on Rosamond Dry Lake, just west of Rogers.

    Finally, on May 9, 1969, flight number seventeen, John A. Manke became the first man to break the sound barrier in a Lifting Body. Flight thirty-four, February 18, 1970, went down in the history books as the fastest lifting body flight when Peter C. Hoag punched through Mach 1.861. Nine days later, Bill Dana took the thirty-fifth flight to an altitude of 90,300 feet, the highest flight of the lifting body fleet.

    She finally took her thirty-seventh and final flight on July 17, 1970, with Hoag at the controls. By this time, she handled like an F-104 Starfighter, better than the rest of the NASA Lifting Bodies. Dale Reed pushed for plans to launch an HL-10 on a Saturn V rocket and allow it to reenter, first unmanned, then with a brave astronaut aboard. He even spoke with Wernher von Braun who was happy to set two Saturn V vehicles aside for these flights. This plan was never realized.

    To prepare the HL-10 for spaceflight would have, of course, meant preparing the vehicle for the intense heating of reentry. Many major design modifications would have been required. One interesting problem was the windscreen; it is a curved bowl at the nose of the vehicle. During reentry, this area would have become the hottest surface, heating to approximately 3,000 °F. No transparent material could have withstood this heating, so the windscreen would have required relocation. This wasn’t all bad, though, because the curved windscreen created a fisheye effect, which made landings difficult, let alone the fact that they were touching down at a speed of 200 mph on a uniform dry lakebed surface which makes it hard to judge altitude. Overcoming these challenges speaks volumes about the engineers and pilots who work in this field.

    The HL-10 stands as a trophy of accomplishment in front of NASA Armstrong Flight Research Center at Edwards Air Force Base, California. Today, lifting body designs are being considered for travel to Low Earth Orbit, all thanks to the fleet that flew from Dryden.