Precision-guided munitions, in their current form, generally are accurate but
still not adaptable enough to the complexities of urban combat, where targets
constantly are on the move, say military experts.
Incidents of fratricide and misdirected weapons seen during the conflict in
Iraq, for example, highlight one specific shortfall in Air Force missiles and
bombs: they cannot be retargeted after launch.
Combat scenarios of the sort seen in Iraq—with a complex target mix ranging
from moving missile launchers to deep bunkers, dispersed troops and dual-use
buildings—have stirred concerns among Air Force planners that their weapons
need to become “more precise and cause less collateral damage,”
said Air Force Col. Pamela Arias, head of the armament product directorate at
the Air Armaments Center.
Accuracy would improve if weapons could be retargeted in flight, officials
said. Cruise missiles and other satellite-guided munitions used today are programmed
with the target’s coordinates, but cannot be redirected if the target
moves after the weapon is launched.
The Air Force now is studying options to install two-way communications links
on weapons. The idea is to take advantage of real-time intelligence—such
as streaming video from unmanned drones—to track target movements and
reprogram the weapon after it leaves the aircraft, if necessary.
“As a result of this war, you will see a push towards that very thing,”
Arias said in a conference call with reporters.
The problem air-war planners face today is that the sources of target information—the
sensors—are sometimes far away from the weapons. Predator and Global Hawk
unmanned aircraft, for example, can see the target, but they don’t necessarily
carry weapons. (Only a small number of Predators are armed) The shooters—the
fighters and the bombers—don’t always see the target.
Although the Air Force for years has been working on technologies to shorten
what it calls the “sensor-to-shooter” cycle, there is still a certain
amount of latency in the process. That creates problems when targets move rapidly.
“The close air-support problem is a challenge, whether it’s in
the desert or whether it’s in a city, because you’re dealing with
delivering weapons in the close proximity of friendly troops,” said Air
Force Lt. Gen. Michael Moseley, the commander of air operations in the Iraq
war.
The answer to that problem is to “network the battlefield,” said
Steve Butler, director of engineering at the Air Armaments Center.
“Now, we give the coordinates to the airplane, not the weapon directly,”
Butler said in an interview. In cases when the enemy is constantly relocating
surface-to-air missile launchers, the only way to hit the target with precision
is to be able to update the location information, he explained. “The B-2
bomber can launch the weapon, but if the SAM keeps moving, the weapon will have
outdated target location. You need a data link on the weapon to be able to constantly
update the coordinates.”
A data link would turn every weapon into a sensor. “With a camera on
board, a small lightweight cruise missile can actually serve as an imaging asset,
like Predator,” said Butler.
The Navy already is developing a weapon that can be retargeted in flight. The
Tactical Tomahawk, a follow-on to the current Tomahawk cruise missile, has a
satellite link with its launch platform and can pass messages, according to
a Navy news release. The Tactical Tomahawk still is being tested and could be
ready for operations in about a year.
The Air Force weapon data link “might be very similar to Tactical Tomahawk,”
said Butler. “We want to get those data links at a lower cost so we can
provide them on lower-cost weapons.”
Limiting data links to just cruise missiles—which cost at least $500,000
each—would not create a big enough network, because cruise missiles are
not used as often as smaller aircraft-launched bombs.
“If you get to smaller weapons, you start thinking in a new way,”
said Butler. “Maybe the weapons start communicating amongst themselves
... share information, loiter—like a Predator—receive information
about targets and quickly respond.”
Weapons could receive target coordinates from Air Force controllers, from forward
observers on the ground, from “whoever had them,” said Butler.
Weapon Candidates
Two candidate weapons that could be upgraded with two-way communications links
in the next several years are the Joint Air-to-Surface Standoff Missile and
a small cruise missile called the Low Cost Autonomous Area Search munition.
The JASSM is scheduled to begin production late this year. The Air Armaments
Center is proposing that the Air Force demonstrate an in-flight retargeting
capability for JASSM. “So far that hasn’t been funded,” said
Butler.
With a data link on JASSM, “someone would be providing an update about
a moving target. JASSM could fly and pick up the target with its own seeker
and then finish the intercept,” said Randy Bigum, vice president for strike
weapons at Lockheed Martin, the manufacturer of both JASSM and LOCAAS.
“We have a heck of a time locating mobile targets,” he said. GPS-guided
cruise missiles or bombs don’t do well against moving vehicles. “We
need something to go in there, search, identify, engage and send back the results
of that mission.”
The Air Force has yet to decide what type of technology could be used to link
weapons. “That is a big question,” said Bigum. “What is the
standard that the Defense Department will establish so we can build a data link
that meets those protocols? We have done it pretty much in the platforms, with
Link 16. An equivalent for weapon data link has not been established.”
Lockheed Martin is working with the Air Force to demonstrate data link capabilities,
Bigum said. The problem is not the technology, but the cost, he said. “It
requires the money that nobody has in their budgets for development and demonstration.”
It would take about two years to engineer and test a data linked JASSM, Bigum
said.
The JASSM onboard computer can be programmed with eight different targets.
The order of the targets can be re-arranged, but cannot be changed after the
weapon is released from the aircraft. “With the data link, you can talk
to it in flight. ... Stealth would not be affected by a data link antenna. We
have antenna technology today that preserves signature.”
The LOCAAS, a loitering munition with a laser-radar seeker—still in development—will
have a two-way data link in 2006, said Arias.
After launch, the munition will loiter over a 25 square-km area and beam images
back to the control station. “Someone will be looking at the data the
LOCAAS is seeing, make a decision and give the authorization to shoot,”
Arias said.
LOCAAS will be competing for production funds under a new program called the
wide-area search autonomous attack munition, or WASAAM.
WASAAM could be described as a “small UAV with both ISR [intelligence
collection] and kill power,” said Arias. “You need a data link on
the weapon to gather data and send it back.” The Air Armaments Center
is lobbying for funds to start the program in 2006.
If LOCAAS works as planned, it would become the first weapon that can execute
“automatic target acquisition,” said Bigum. The laser-radar employs
a laser beam to create three-dimensional images of enemy vehicles, for example.
Those pictures would be compared against a library of models pre-programmed
into a computer, allowing the munition to identify the exact type of vehicle,
such as an SA-6 missile launcher or a T-72 tank. Then, “it will orbit
until you approve the engagement,” he said.
The resolution of the laser-radar is orders of magnitude higher than other
sensors, Bigum said. While two-dimensional radar resolution is measured in feet,
the laser-radar resolution is measured in fractions of an inch. That technology
can be useful for urban combat, because, Bigum said, the laser-radar is unlikely
to confuse a bus with a missile launcher.
Depending on the quantities produced, each LOCAAS would cost at least $100,000
per unit. If the Air Force funds the program in 2006, the munitions could be
in operation by 2010.
The notion of data-linking munitions such as LOCAAS opens up new concepts of
operations, said Butler. If LOCAAS or WASAAM could “talk to one another,”
they could coordinate “swarming” attacks, where all the weapons
are looking for one target. “One of the weapons sees the target, radios
everyone else, so they all swarm to that area and attack that one target.”
The swarming would make it difficult for a target to get away, said Butler.
“If there is a dispersion of targets, one of the weapons sees the target
and lets the others know.”