Defense Intelligence Reference Document Laser Lightcraft Nanosatellites

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Lightcraft Air to Space Investigation
One Ballistic Missile Defense (BMD) mission already being investigated by the Air Force
for high-power airborne laser systems is the focusing of their intense beam energy on
enemy ballistic missiles over dwell times sufficient to heat missile materials to high
temperature thus causing structural failure. Another BMD mission that involves high-
power airborne laser systems was examined during this investigation (see Figure 15).
This mission entails ballistic missile destruction above the atmosphere during the
missile's unpowered descent phase of flight. In this case, it is envisioned that the high-
pulsed power within high-energy laser beams would first be used to rapidly examine
each object within the incoming threat cloud and, based on each threat-object's
response, discriminate warhead-carrying vehicles from lighter decoys and non-
threatening debris. Next the pulsed power within the high-energy laser beam would
guide a Lightcraft to the warhead-carrying vehicles while accelerating the Lightcraft to
the flight velocity needed for warhead vehicle destruction by kinetic energy kill. And
intermittently during the trajectory, the laser illuminates the warhead vehicle instead of
the Lightcraft for guidance updates and terminal semi-active seeker homing.
Threats from space, other than ballistic missiles, were mentioned in the Rumsfeld 2001
Space Commission Report [27]. Dne threat to U.S. space assets specifically cited was
microwave signal-jamming from relatively unsophisticated and inexpensive enemy
satellites [28]. Eliminating such satellite threats has not been examined in detail, but
they could be rapidly eliminated by air-to-space Lightcraft, if sufficiently precise
azimuth and elevation information can be obtained to point Lightcraft lasers at the
jammers.
"Hit-to-kill" accuracy and high impact energy requires Lightcraft maneuvering such that
ballistic missile intercept occurs at relatively small angles from a head-on collision
course. Tables 4 and 5 show the influence of such angles, together with Lightcraft
velocity and enemy ballistic missile velocity, on Lightcraft impact energy and required
mass. It is seen in both tables that intercept angles up to 45° from head-on collision
courses do not significantly influence Lightcraft impact energy or required mass; that
high Lightcraft impact energies are achieved with relatively low masses (1.0 kg); and
that required Lightcraft masses for relatively high impact energies (10 MJ) are very low
for Lightcraft velocities in the 2 km/sec to 4 km/sec range. It is also seen that the
interception of longer range ballistic missile threats results in higher collision energy for
a given Lightcraft mass and speed. That is because the higher entry speed of longer-
range missiles contributes more collision velocity (target plus Lightcraft velocity
component along the target velocity vector).
This BMD air-to-space mission appears to be more favorable for Lightcraft than air-to-
ground/sea or air-to-air missions, which are not considered here because they are
beyond the scope of this report. This mission results in higher altitude flight where
atmospheric propagation losses of laser beams are lower, and in higher impact
velocities for higher Lightcraft impact energy or lower mass. But like air-to-air
missions, BMD would require semi-active terminal guidance using uncooled IR detectors
and chemical rocket thrusters for end-game maneuvering to ensure hit-to-kill accuracy.
It is therefore estimated that the air-to-space Lightcraft dry mass would be about the
same as the air-to-air Lightcraft (approximately 2.0 kg). This particular Lightcraft
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