posted on Jun, 21 2004 @ 12:51 PM
Late in the year of 1954, the National Advisory Committee for Aeronautics
(NACA) issued a requirement for an air-launched manned research
vehicle with a maximum speed of more than Mach 6 and a maximum altitude
of more than fifty miles. North American Aviation Incorporated was
awarded the contract for the new research vehicle, the X-15.
Developed under USAF Project MX-1226, three X-15s were built and
together made 199 flights during a research program which lasted
from 1959 to 1968, exceeding all speed and altitude goals set. The
X-15 was designed to fly at speeds of Mach 6 and altitudes up to
250,000 feet. The aircraft went on to reach a maximum speed of Mach
6.7 and a maximum altitude of 354,200 feet. Mach 6 is about one
mile per second and flight above 265,000 feet qualifies an Air Force
pilot as an astronaut.
The X-15 made its public appearance on 15 October 1958 at North
American's Los Angeles facility and the first of the three X-15s
arrived at Edwards AFB two days later. On 10 March 1959, with project
pilot A. Scott Crossfield at the controls, the X-15 made its first
captive-carry flight under the right wing of a B-52 carrier aircraft.
On 8 June 1959, it made its first glide flight, reaching a speed
of 522mph (Mach 0.79) from a release altitude of 52,341 feet.
During a test flight, the X-15 would be air-launched by NASA's
converted B-52 at an altitude of 45,000 feet and a speed of 500
mph. Generally, there were two types of flight profiles: high-speed
or high-altitude. High-speed flights were usually conducted below
an altitude of 100,000 feet and flown as a conventional airplane
using aerodynamic controls. High-altitude flights began with a steep,
full-power climb to leave the atmosphere. This was followed by up
to two minutes of "coasting up" to peak altitude after the engine
was shut down. High-altitude flights usually lasted for 2-5 minutes
as it made a ballistic arc before reentering the atmosphere. A reaction
control system, employing hydrogen peroxide thrusters located on
the nose and wings, was used to maintain attitude above the atmosphere.
A typical research flight lasted about 10 or 11 minutes while
covering nearly 400 miles along a course that stretched from Smith
Ranch, Nevada to Edwards Air Force Base.
The X-15 program made many accomplishments, here is list of some
of its contributions to space flight:
First use of a full-pressure suit for spaceflight.
First use of reaction controls for maneuvering in space.
First use of a flight control system that automatically blended
aerodynamic and reaction controls.
Development of thermal protection for hypersonic reentry.
Development of the first large, restartable, and throttleable
Development of an inertial guidance system.
Demonstration of a pilot's ability to operate in "micro-gravity".
Demonstration of the first piloted reentry-to-landing from
Acquisition of hypersonic acoustic measurements, which influenced
structural design criteria for Mercury capsule.
Verification of the validity of hypersonic wind tunnel data,
which were later used in the design of the Space Shuttle.
(Special Research/Experimental A/C)
Jun 8 1959
No. of Engines:
Motors XLR-99 rocket engine