Documents / Official release
This Defense Intelligence Reference Document (DIA-08-1011-001), dated 1 November 2010, was prepared by the Defense Intelligence Agency's Defense Warning Office under the Advanced Aerospace Weapon System Applications program. It covers nanosatellite technologies, laser Lightcraft propulsion, a weapon mission selection study and a multi-megawatt laser study. The author recommends that the Department of Defense, working with NASA, bring laser Lightcraft propulsion research back to the United States and restart the Air Force X-50LR test flight program.
From the source:Release of 2026-09-18 Incident: 11/1/10, Las Vegas, Nevada. Released with redactions. This document is a Defense Intelligence Reference Document (DIRD), a technical reference format used by the Defense Intelligence Agency (DIA) to capture baseline knowledge on a specific topic for later analytic use. DIRDs are best understood as reference and synthesis products rather than as original research. It is one of 38 DIRDs produced under the Advanced Aerospace Weapon System Applications Program (AAWSAP) between 2009 and 2011. Because AAWSAP’s scope permitted a broad range of supporting topics, not every DIRD in the series directly concerns aerospace systems or future threat assessment. The following summary reflects the DIRD’s scope and framing at the time of writing and should not be read as implying current validation of the concepts discussed. This DIRD examines laser-propelled “Lightcraft” as a possible low-cost method to launch very small satellites into low Earth orbit by using a remote high-energy laser to supply most of the propulsion energy rather than relying entirely on onboard energy sources. The report combines a survey of nanosatellite trends with a review of “Lightcraft” propulsion concepts, vehicle design, beam-control requirements, and mission studies, and argues that the most promising application is the launch of nano- or pico-satellites, especially Earth- and space-observing payloads of a few kilograms or less. It presents the concept as potentially much cheaper than conventional multistage rockets for very small payloads, while also noting significant practical constraints including strict beam-riding geometry, atmospheric losses, demanding pointing and adaptive-optics requirements, and heavy dependence on large ground-, sea-, or air-based laser infrastructure. Overall, the document presents laser “Lightcraft” as a technically plausible launch concept whose attractiveness depends on whether the supporting laser and beam-control system can be made reliable and economical at operational scale.
UNCLASSIFIED/;'POR: OPPICIAE USE 014Lf deemed possible with emerging MEMS technologies being developed under the National Nanotechnology Initiative for both chemica l and FEEP thrusters (see Chapter 2 for details). It was also found that the currently configured composite structure for the Lightcraft forebody must be reduced from 2-ply to 3-ply (with the same ply-thickness) to meet Lightcraft airframe mass requirements. Another important finding in the study was the significant influence of the ground - based laser wavelength (>..) on Lightcraft performance. Figure 8 illustrates the adverse beam propagation geometry associated with ETO laser propulsion by means of ground-based lasers. It is seen that beam propagation distances through the Earth's atmosphere are short during initial flight phases when the path length traveled by laser energy to the Lightcraft is least. But during latter flight phases (when the vehicle itself is above the sensible atmosphere) the beam propagation path within the atmosphere is much longer, and power losses due to atmospheric attenuation become ever greater with increasing range. And since power losses due to laser beam spread ing - even in vacuo - also increase with increasing distance from the laser, power losses are greatest at the end of laser propulsion (when vehicle distance from the laser is greatest). For a ground-based laser with given aperture diameter, adaptive optics, atmospheric conditions, and radiated power, the laser power collected by the Lightcraft was found to be extremely sensitive to laser wavelength. Here, >.. determined the amount of radiated laser power lost through "thermal blooming," turbu lence, and "extinction" during beam passage through the Earth's atmosphere in addition to the power lost from "diffraction" (beam spreading at longer ranges) during propagation through the vacuum of space. And since each loss mechanism was a function of>.., Froning and Davis considered each loss mechanism in their estimation of lost power for the six different laser wavelengths associated with the six different ground-based laser candidates that were evaluated in the study. Shown in Figure 10 (without dimensions) is the fraction of radiated laser power collected by the Lightcraft at maximum laser propulsion range (when necessary "cut off" velocity for orbital flight is achieved) for the spectrum of wavelengths investigated. It is seen that a significant fraction of laser-radiated power is lost, even if there were no atmospheric transmission losses at all. And add itional losses associated with beam propagation through the atmosphere are seen to result in power losses on the order of 75% to 99%. Figure 11 shows that significantly more power would be available at the end of laser airbreathing flight than at the end of laser rocket flight. This might benefit surface-to-air Lightcraft missions that would mainly entail airbreathing flight. UNCLASSIFIED'I i'FAA: 061i1Clali.k W&& 8PtLY 21
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Official release, from the pursue collection. The PDF is mirrored here; the original link is above. 77 pages are in the text index: search them above, or from the library's search.