LGarde, also L'Garde or L·Garde, is an American aerospace and defense technology company founded in 1971 in Orange County, CA[1] and is the primary contractor for the Sunjammer spacecraft, the world largest solar sail.

[7] The company's unusual name is an acronym formed by the initials of the founding partners: Bill Larkin, Gayle Bilyeu, Alan Hirasuna, Rich Walstrom, Don Davis.

[13] A project, conducted with JPL under NASA's Gossamer Spacecraft program[14] in 1999, sought to build an inflatable reflector to concentrate solar energy for space electrical power generation, while acting as a large aperture high gain antenna.

[15] Additional development came in 2005, when LGarde began utilizing material rigidization methods that provide a long lasting reflector shape without requiring continuous inflation.

In 2003, LGarde, together with partners JPL, Ball Aerospace, and Langley Research Center, under the direction of NASA, developed a solar sail configuration that utilized inflatable rigidized boom components to achieve 10,000 m2 sailcraft with a real density of 14.1 g/m2 and potential acceleration of 0.58 mm/s2.

[19] Additional advancement of the solar sail project came as LGarde engineers improved “sailcraft” coordinate systems and proposed a standard to report propulsion performance.

[23] To control its orientation, Sunjammer would have used gimballed vanes (each of which is itself a small solar sail) located at the tips of each of its 4 booms completely eliminating the need for standard propellant.