AAWSAP DIRD, Laser Lightcraft Nanosatellites, November 2010

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.

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propulsion requires a modest 0.1 to 10 MW of total beam power. The ground-based
megawatt-class laser beam generator is state-of-the-art technology. The cost of
generating electrical power for the ground-based laser beam generator is ~ $0.10/kWh,
which translates to < $2/kg of payload. An SDIO study [10, 11] showed that all launch
to orbit conditions for a Lightcraft could be satisfied by a single, high -power ground
based laser - with or without the aid of a low altitude laser relay mirror or space-based
laser beam generator system. The majority of the system mass required to launch a
payload to orbit is left on the ground in the form of the beam generators and their
electrical power sources. The dry spacecraft mass can be further reduced by two
orders of magnitude, and thus the operating costs reduced by a factor of 10 (to <
$2/kg of payload), if Buckytubes are used to construct the vehicle and its subsystems.
LIGHTCRAFT NANOSATELLITE CONFIGURATION
As shown in Figure 7, the Lightcraft nanosat configuration consists of: 1) a con ically
shaped "forebody" for lift and aerodynamic compression of ingested airflow (prior to its
detonation by laser heating during atmospheric flight); 2) an annular "cowl" or "shroud"
with in which air detonation or propellant ablation (by intense laser heating) occurs; and
3) a parabola-shaped "afterbody" whose mirrored surface focuses beamed laser energy
into regions of sufficient sma llness for intense air or propellant heating to occur. And as
shown in Figure 8, the vehicle is powered by laser airbreathing propu lsion (by
detonation of air) until hypersonic speed within the sensible atmosphere is reached;
and then the vehicle is powered by laser rocket propulsion (by heating of propellant)
during flight above the sensible atmosphere, until cut-off velocity for orbital flight is
reached.
Shroud (Cowl):
within which Laser • Laser Airbreathing Flight
Heating of Airflow from Zero Velocity to
and Propellant Hypersonic Speed
Occurs
Afterbody: with
Mirrored Surface
for Focusing Laser
Energy into the Laser
Shroud (Cowl)
\ Beam
.______ ___ __ _________ }__
Forebody: for Lift
and Compression • Laser Rocket Flight from
of Airflow during Hypersonic to Orbital
Atmospheric Flight Axi-Symmetric Body Speed
Figure 7. Lightcraft Concept 1261.
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