Abstract
The founders of Laser Propulsion (LP) viewed laser ablation as a key physical mechanism for generation of thrust. Three decades of systematic studies have shown that the role of laser ablation in LP is rather indirect and different from what has been expected. This paper reviews the effort to revise the original idea of using “direct” laser ablation of matter for propulsion, conducted at the University of Alabama in Huntsville. The study evolved from the formulation of the concept in 1999 to the first in-lab flight demonstrations in 2004. The physical principles of ablative laser propulsion (ALP) will be reviewed. The discussion will be focussed on our studies, conducted with three independent techniques: ion time-of-flight, force measurements and plasma imaging. From these experiments such characteristic parameters as specific impulse, coupling coefficient and efficiency were deduced. These results were finally corroborated by flight demonstration. The paper is concluded with discussion of future prospects for development of ALP.
