The US Air Force Research Laboratory's Propulsion Directorate, Edwards AFB, California, has conducted two test flights of a prototype of the Lightcraft laser-propelled spacecraft, in a laboratory at the White Sands Missile Range, New Mexico.
The first test reached a distance of 4.2m, and the second achieved 121m horizontally. Flights to an altitude of 1km are now planned.
The 50g, 150mm-diameter solid aluminium prototype was propelled by a ground-based10kW Textron high-energy, pulsed carbon-dioxide, infra-red laser. The Lightcraft - intended originally as a Strategic Missile Defense Initiative microsatellite - is designed to convert kilojoule pulses of laser energy, focused ten times a second onto a parabolic mirror at its base, into propulsive thrust.
The laser energy is concentrated to extremely high intensities, sufficient to burst inlet air momentarily into highly luminous plasma (10-30,000¹K), with up to ten atmospheres pressure, providing thrust.
An operational Lightcraft, with onboard propellant, would fly to Mach 5 on an airbreathing engine and then shift to laser-propelled rocket mode.
Source: Flight International