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Илья Григоренко
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21.02.2001 13:05:16
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Рубрики
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Современность; Армия;
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US Army
The Evolving Battlefield
National defense with maximum precision and minimum unintended damage should be
an attractive challenge for scientists seeking to improve the human condition.
John S. Foster and Larry D. Welch
In recent years, physics and other sciences have contributed extensively to an
emerging national-security goal that "for every desired battlefield outcome there
should be a precise and well-defined action."
Since before World War II, the US military has been benefiting from an accelerating
cascade of scientific and technological advances: turbojet engines, radar, nuclear
weapons, missiles, computers, high-resolution sensors, navigation aids, satellites--a
continuing and expanding list. These capabilities revolutionized the effectiveness of
military forces in their day. But, over the past two decades, we have seen a new
revolution in the precision of military capabilities, once again underwritten by science
and technology: precision weapons, precision navigation, precision surveillance, and
precision command and control.
Precision plays a key role in the present reality and future expectations of military
force application. Achieving a desired precise outcome requires precision across a
spectrum of activities ranging from geopolitical judgments to weapons accuracy.
Much of what one needs for improving geopolitical judgment is, of course, beyond
the purview of science. But even there, the products of science and technology
make important contributions. Nonetheless, we focus here primarily on the
contributions of science and technology to achieving the desired result against
military targets, and on the need for their future contributions to improving precision
in selecting and engaging such targets.
The evolution of precision
The implications of precision in the application of military force are far-reaching.
Scientists have faced a moral dilemma. Their discoveries served to promote
important human values, but often at the price of increasingly more destructive
weapons that produced not only more combat casualties but also more collateral
death and destruction outside battlefields and military targets.
But in the past two decades, the application of science and technology has made
possible a dramatic reversal of this baleful trend. In the last five months of World
War II, for example, American bombing raids claimed the lives of almost a million
Japanese civilians--not counting Hiroshima and Nagasaki. On one night in March of
that final war year, 234 B-29s dropped a thousand tons of incendiary bombs over
downtown Tokyo, killing 84 000 people.1 More than two decades later, in the
Vietnam conflict, the US dropped almost three times as much explosive tonnage as
we used in World War II, killing an estimated 365 000 Vietnamese civilians.2
Then in Desert Storm we saw the implications of precision in selecting targets and
directing force against them. Every incident of unintended destruction against
noncombatants became an object of press, public, and political attention. For the
first time, the pursuit of more effective military force was compatible with dramatic
reduction of unintended death and destruction. This new capability also became a
political imperative.
Meeting the demands of this political imperative has led to ever more demanding
standards of precision. In World War II, "daylight precision bombing" was the
euphemism for armadas of heavy bombers delivering many hundreds of bombs, with
large average errors, in the hope of inflicting significant damage on a military target.
How much have things changed? In World War II,
successfully attacking a 60-by-100-foot target
required 3000 sorties dropping 9000 bombs with a
circular error radius of more than 3000 feet.3 Most
of the damage was not to the intended military
target but instead to nearby streets and buildings.
Today, by "precision" we mean achieving the
desired result with a single weapon delivered with
high accuracy at the right time to advance the military objective. (See figure 1.) And
the standard continues to change. For some years, the goal was to achieve a
consistent accuracy of better than 10 meters. Now it is argued that the term
"precision" should be reserved for a consistent accuracy of 1 m or less. But
precision has to do with a broader range of capabilities than just the spatial accuracy
of delivery. The imperative for more precision also extends to "friendly" combat
losses.
Reducing the cost to combatants
During the buildup for the Gulf War, estimates of expected US casualties4 in ground
combat ranged up to 30 000. There was good reason for such estimates. Table 1
provides some historical insight into such an expectation, and contrasts it with the
much more benign eventual outcome.5
Combat aircraft losses followed a similar pattern. Even though US aircraft were
facing extraordinary advances in air defenses, our combat planes drastically and
continuously cut their losses. By the time of the Kosovo conflict, we could expect
very close to zero losses. That expectation became reality as NATO lost only two
aircraft and no crew members in some 10 000 attacks against ground targets.6
There were many reasons for the drop in casualties among aircrews and ground
forces, but prominent among them is the concept of "rapid decisive operations,"
made possible by scientific and technological innovations. Rapid decisive operations
are designed to achieve an operational goal with greatly reduced exposure to risk.
Their impact is also evident in table 1, which reminds us how many more sorties
were flown in Vietnam, with high cost and questionable success, than in the much
more quickly resolved Gulf War.7
Regimes of precision
Producing the desired results from precision use of
force requires a connected set of "regimes of
precision." The capabilities range from battlefield
action to concept formulation. The precision
regimes range from defining purpose to assessing
results and adjusting goals, means, strategy, and
tactics. These regimes interact in continuous
iteration. Figure 2 illustrates a set of these regimes
and the layers of enabling activities they require.
Precision in purpose and objectives is the essential starting point. It has both political
and operational dimensions. While acknowledging the importance of the precision in
the political aspects, we focus here on the operational dimensions.
An important prerequisite to operational precision is knowing, at the outset, what is
likely to be possible and adjusting to what actually turns out to be possible as the
results unfold. Precision in assessing results must serve the purpose of adjusting
objectives that prove to have been unrealistic.
Precision will lead to operations in which very agile forces can respond potently
within hours to shape the battlespace before the adversary can set the conditions.
Interdependent forces will, at first, deploy only essential capabilities to the conflict
site, relying on robust communications and precise remote firepower support as
needed.
Commanders at all levels will share a continually updated understanding of
objectives and the operations of both friendly and enemy forces. The commanders
can then act in harmony, quickly and decisively, at a pace that no adversary can
match, regardless of his access to commercially available communications and
sensors.
Layered surveillance and reconnaissance systems--satellite, airborne, and
ground--will provide commanders at all levels with the operating picture most
relevant to their situations. Each commander will be able to continually tailor the
requisite information for battlespace decisions to meet changing needs. The
battlespace will be increasingly dynamic, and static information will quickly become
irrelevant.
Lightweight, fuel-efficient vehicles will provide mobility. Units will be able to
maneuver rapidly to engage the adversary under conditions controlled and selected
by friendly forces. Our forces will operate under a protective shield based on
information and agility. They should quickly be able to establish the conditions for
operations virtually free of enemy interference. The adversary will be quickly driven
to a reactive, defensive mode.
Rapid decisive operations
Science has made possible an impressive array of technologies for enhancing military
precision. "Rapid decisive operations" is a useful unifying rubric. It can apply to any
battlespace or to other venues, ranging from supporting humanitarian operations to
responding to major aggression. Figure 3 illustrates some of the concepts that help
us define what is needed from science and technology.
The inner ring in the figure lists very general capabilities required for the achievement
of rapid decisive operations:8 Strategic and operational agility is the ability to
assemble the needed forces rapidly where they are needed. Decision superiority
results from having better information than the adversary. It makes possible the
operational pace and precision that ensure full control of the situation at the lowest
human cost. Multi-dimensional precision engagement describes the ability to
apply varying levels of appropriate force when and where intended while avoiding
unintended consequences such as collateral damage. Full-dimensional protection
is achieved when our operations can proceed virtually free of enemy interference.
The outer ring of figure 3 lists more specific
requirements for implementing the general goals.
These specific needs involve technological and
scientific challenges. Table 2 lists a number of such
specific challenges.
The challenges
"No-move" zones. A no-fly zone has been used effectively in Iraq. This experience
suggests the desirability of something broader--a no-move zone that could be
enforced against ground vehicles. Such a capability could deter an invasion force. It
could also detect and target missile launchers and other mobile weapons that emerge
from hiding.
One possibility would be to deploy radar satellites in sufficient numbers to provide
almost continuous coverage of areas under scrutiny. The satellites would search for
moving targets and then revert to imaging mode to identify an interloper for targeting.
In the synthetic-aperture mode, the radar's wideband waveforms can provide spatial
resolution of less than a meter. For good angular resolution, the signal processing
would use the radar satellite's motion to provide differential Doppler shifts at
different angles.
This emphasis on detecting movement suggests a new surveillance and intelligence
discipline, in addition to the traditional concentration on signals, imaging,
measurement, and human intelligence activity. In the dynamic battlespace,
"movement intelligence" might well be the most valuable kind of information for
commanders. Near real-time response might be achieved with high-speed ground or
air-launched standoff missiles guided by information from the Global Positioning
System. That would require either additional onboard sensors or accurate registering
of the operations area and accurate update of the GPS coordinates.
At all hours, in all weather. For much of the last half century, our opponents owned
the night. Night was their time of recovery and repair, because US air and heavy
ground forces were largely ineffective in the dark. Furthermore, we were unable to
use air power, one of our greatest advantages, in marginal weather. Thus we were
disadvantaged more than half the time.
We saw a sharp reversal of such limitations in the Gulf War. But precision night
capability is still only available in a limited part of our air and ground force. And
precision all-weather capability, provided by highly accurate radar accurately
registered to geographic references, is available to only a small fraction of our
forces. Over Kosovo, only the half-dozen B-2 bombers provided true all-hours,
all-weather precision capability. They achieved the requisite precision by using
synthetic-aperture radar to get bearings and range to target. This information was
used to update GPS information and the initial measurements. The updated
information was given to the weapon that was to be launched and guided to the
target.
Although technological solutions already exist, they are expensive and complex. So,
once again, we need scientific and technological breakthroughs to provide
affordable, lightweight, reliable capabilities. Given the exponential increases in
computer processing power and the commercial proliferation of sensors, it should be
possible to reduce cost and complexity by at least an order of magnitude, so that
true all-weather, all-hours precision strikes become the operational standard.
Beyond the line of sight. Historically, tank cannon have provided precision
capability within the line of sight. During Desert Storm, for example, US forces
repeatedly demonstrated that our tanks could score a high percentage of first-round
hits when the target was within sight. But there are compelling reasons for wanting
that capability to extend beyond the line of sight.
The Defense Advanced Research Projects Agency (DARPA), the army, the navy,
and supporting contractors are pursuing this goal. One approach is a GPS-guided
5-inch artillery round with inertial backup guidance provided by a
microelectromechanical system (MEMS) on a chip. Rocket assist provides
extended range. The goal is an accuracy of about 10 meters at a range of 100 km.
But one needs to reduce sharply the present cost of about $40 000 per round. We
will also need a compatible targeting and damage-assessment system.
Through trees and buildings. Precision warfare requires the ability to locate targets
concealed under heavy foliage or in built-up urban environments. Microwave radars
can provide precision location by detecting motion or employing synthetic-aperture
modes. But microwave radar suffers high attenuation (of order 99%) when passing
through heavy foliage.
At longer wavelengths (UHF and VHF), radar
is much better in dealing with foliage. Several
such radars on airborne platforms have
demonstrated the ability to detect moving and
stationary targets under foliage. Figure 4
displays the results of experiments by the
Lincoln Laboratory on the probability of
detecting and identifying targets from above a
forest in Maine at various radar frequencies.
The low frequencies, however, require large
antennas to provide range and resolution. Therefore, practical approaches to
detecting targets under foliage remain a formidable technical challenge. Furthermore,
none of the radar solutions is practicable in urban settings. The urban solution is
likely to require combinations of microelectronics, miniature optical systems, and
microrobots.
DARPA currently has a program to develop the necessary microrobots. The
principal sensor for such tiny vehicles is a silicon CCD electro-optical device with
both narrow and wide fields of view, capable of operating in daylight and starlight.
Data can either be stored for later readout or transmitted via a communications
relay. The robots could navigate by GPS or other means. Propulsion might be
provided by miniature fuel cells. Miniaturizing communications and antennas is
another substantial challenge.
Finding land mines. An estimated 100 million land mines are currently deployed
around the globe. Each month, these mines claim about 2000 unintended victims. In
the Bosnian conflict alone, more than two million mines were laid. These mines
continue to constitute a serious threat.
An intensive campaign by DARPA and the army over the past several years has
demonstrated some revolutionary techniques. The campaign has included
competitive teams made up of people from academia, industry, and government
laboratories. The techniques range from using vapor-sensitive polymers to the use of
Raman scattering, which shifts the radio frequencies by an amount unique to each
chemical structure. The quadrupole resonance technique, which has shown great
promise, is similar to magnetic resonance imaging. The ground is irradiated with
frequencies of a few megahertz in submillisecond pulses that tip nuclear spins. The
nuclei then reradiate at frequencies that are unique to the compounds of interest
(such as TNT, PDX, or HMX).
While work on these techniques has moved the state of the art to real possibilities,
the scope of the challenge continues to demand more efficient, reliable, and
affordable approaches.
Jam-resistant communications and navigation. Precision military operations will
depend critically on making better information available to the decision-maker--at
every level from the senior political leadership to the squad leader. This will require
reliable, high-bandwidth, readily available communications that can reach anywhere,
anytime, with precise information on the location of hostile, friendly, and neutral
forces. At present, such a ubiquitous capability depends on space-based support.
For a number of years, an underlying assumption has been that the commercial
demand for space-based communications would provide a ready resource for much
of our national security needs--even in remote places--and that such capability
would be reliable, high-bandwidth, reasonably secure, and reasonably jam resistant.
In recent years, however, we have seen trends that may necessitate reassessment.
There has been a drastic change in the expectation of growth in demand for
commercial communications satellite services. For a rapidly expanding set of
applications, new technologies are making fiber optics the preferred approach. It is
often cheaper and more reliable, and it is increasingly available where commercial
demand is high. Further advances, such as 128-color fiber optics, will only enhance
the marketplace preference for fiber optics over satellite communications.
Unfortunately, fiber optics may not serve national security needs in places where
wideband, reliable, secure communication is required. We may be operating in
locations where there is no entry to a fiber optic system. Furthermore, in some
settings, fiber optics can be vulnerable to hostile action. Thus we will need
breakthroughs in satellite communications that will serve the needs of both
commercial and national-security customers. The requirement is easily described:
We will need the same order-of-magnitude improvements in the effectiveness of the
transponders on space-based systems that we have come to expect in terrestrial
communications. Absent such improvements, we will either have to devote very
large additional resources to inefficient systems or we must accept a lower standard
of precision application of national power.
Managing sensor complexes. With the advent of precision guided munitions, the
key to precision application of combat power has shifted from lethality to target
detection and selection. This will inevitably require layers of distributed sensors. That
creates a demand for a new battlespace function: sensor management. Controlling a
suite of sensors will require artificial-intelligence algorithms that can assist in rapidly
optimizing and reconciling sensor coverage.
Rapid and continuous visualization tools are also needed to assist the human
controller. And more reliable automatic target-recognition will be essential to the
efficient use of sensor data to direct effective operations.
Extensive experimentation will be needed to learn what works. There will also have
to be more powerful human-in-the-loop battlespace simulations, to work out
doctrines and procedures, test concepts, rehearse operations, and train operators.
Real robotics for real combat. For at least three decades, the promise of robotics
has largely been just that: a promise of things to come. Still, important technological
advances have been made over a wide range of development paths. For this
discussion, we chose to use the broadest definition of robotics. In this context, the
purpose of robotics is to perform the many tasks now performed by human
combatants that could be performed better or more safely by machines.
Extensive and exciting work is going on in robotics. Let us consider some often
overlooked, though widespread, application of robotics already used in combat
systems. Modern aircraft flight-control systems, computer-driven stability systems in
armored vehicles, and aircraft approach systems are examples of robotics
performing tasks better than human combatants and allowing the human to focus on
those tasks at which we are better than the machines.
Competitive advantage would seem to be the appropriate criterion for deciding what
to attempt with robotics. Humans are generally better than machines at quickly
assimilating large amounts of information from a variety of organic and other sensors,
and organizing that information for making fast decisions across a wide range of
situations. On the other hand, robotics generally has the advantage for relatively
simple tasks.
The point is that, for some years to come, robotics will be most useful when it
enhances the human capability for making decisions. In uninhabited air combat
vehicles, for example, the robotic system is likely to be most effective and versatile if
we take the pilot's brain along, so to speak, and leave the body back on the ground.
In fact, for some applications we might use one brain to manage several vehicles; for
others we might want several brains for one vehicle.
All this is possible if we can work out how to reliably connect the pilot's brain to the
pilotless vehicle. The advantages could be revolutionary. Freed of the need to
support and conform to the limitations of the human body, we can have combat
systems of unprecedented effectiveness and versatility. We could have surveillance
vehicles that stay aloft for a week, or fighter planes that could maneuver at 20 Gs.
We could also have miniature systems--about the size of birds or small
mammals--that operate freely in urban terrains.
Underlying science and technology
There are still missing pieces needed to provide even the limited set of capabilities
described above. Having seen the startling results already achieved in commercial
communication, computational science, biochemistry, and other fast-moving
technological fields, we believe that the best way to address these national security
challenges is to focus the attention of some of the best minds in the world of science
and technology on them.
The goal is to support national security interests with the greatest possible precision
and the least possible unintended damage. That must surely be an attractive
challenge to scientists who would much prefer that their contributions serve to