Perspective on Research in Laser Propulsion

Overview

The document titled "Perspective on One Decade of Laser Propulsion Research at the Air Force Research Laboratory" provides an overview of the advancements and research conducted in the field of laser propulsion over nearly a decade. Authored by C. William Larson from the Electric Propulsion Laboratory at the Air Force Research Laboratory, the paper discusses the experimental research carried out using the Pulsed Laser Vulnerability Test System (PLVTS) at the High Energy Laser Systems Test Facility located at White Sands Missile Range, New Mexico.

The Air Force Laser Propulsion Program, which spanned approximately ten years, involved around 35 weeks of experimental research. The PLVTS is a pulsed CO2 laser capable of producing up to 10 kW of power in a spot size of about 10 cm², operating at a wavelength of 10.6 microns. It can achieve a pulse repetition rate of up to 25 Hz, with pulse durations of approximately 20 microseconds. The research focused on generating propulsion thrust from laser energy through the heating of air and the ablation of various candidate rocket propellant fuels.

One of the significant achievements highlighted in the document is the successful flight tests conducted with an ablation fuel known as Delrin, which, when combined with air, allowed a model Laser Lightcraft vehicle to reach altitudes exceeding 200 feet. The vehicle was optimized for propulsion using the PLVTS at its maximum output of 10 kW and 400 J per pulse.

Additionally, the paper discusses the development of a mini-thruster standard for testing chemically enhanced fuels and presents theoretical calculations regarding the performance of formulations containing ammonium nitrate and Delrin. These contributions are crucial for advancing the technology and understanding the potential applications of laser propulsion systems.

The document also notes the increasing frequency of peer-reviewed publications on laser propulsion, indicating a growing interest and investment in this area of research since 1973. Overall, the paper serves as a comprehensive summary of the progress made in laser propulsion technology, emphasizing its potential for future applications in aerospace and other fields.