U.S. Special Operations Command officials are considering novel
weapons enhancements for AC-130 gunships, beloved by operators for
their ability to bring withering fire on enemies. Ideas include
controlling weaponized unmanned craft and lobbing mortar rounds
from the aircraft.
Although these projects have been discussed for years, only recently
has SOCOM taken steps to fund alternatives for its gunship fleet.
These concepts are being tested while a change in weapons is already
underway. The 25 mm and 40 mm guns currently on board will be replaced
with two 30 mm Mk44 Bushmaster II cannons, the first-ever use of
the weapons from a fixed-wing aircraft.
Bofors Defense manufactures the M61A1 40 mm cannons, and General
Dynamics makes the GAU-12 25 mm weapons currently used on the AC-130.
The M61A1 has already been removed from the active inventory, SOCOM
sources told National Defense, and the 25 mm guns are next to go.
“General Dynamics will still make the mounts, but the new
weapons will be made by someone else,” confirmed General Dynamics
spokesman John Suttle.
Alliant Techsystems produces the 30 mm Bushmaster. The MK44 is
also the U.S. Marine Corps’ weapon for its Advanced Amphibious
“The GAU-12, while very capable, is a highly complex system
that requires extensive maintenance to keep up,” said Air
Force Maj. Ken Hoffman, spokesman for SOCOM. “Long-term costs
of both the gun and munitions necessitate a lower cost and a more
The first of four 30 mm-configured airplanes will be delivered
to the Air Force Special Operations Command late this year, according
to Tom Larock, of Boeing Integrated Defense Systems. The rest will
go into service in 2006.
Alliant stated in a news release that the weapon “will enhance
the aircraft’s ability to destroy enemy armored vehicles by
significantly increasing its stand-off distance while providing
more firepower on target.”
While the increase in range is welcome, the new gun systems will
not fully address the most pressing concern about the AC-130—its
vulnerability to anti-aircraft weapons, especially missiles.
The AC-130 gunship is a C-130 transport modified with side mounted
guns and various sensors. It comes in H and U variants, the former
hailing from the Vietnam era and the latter built in the 1990s.
SOCOM said current plans have the gunships remaining in service
through 2030. The planes earned their reputation during the Vietnam
War, when the gunships were credited by the military with destroying
more than 10,000 trucks, as well as providing critical close air
support. But as air defenses became more sophisticated and widespread,
the gunships were forced to fly at higher altitudes. This kept them
safer, but also hampered the aircraft’s ability to hit targets
Analysts and military officials saw the problem looming, and dedicated
studies to finding a solution. And although the problem was clear,
no remedies were attempted.
“Intending to counter this trend, the Air Force commissioned
a number of studies during the early 1990s to examine alternative
weapons,” wrote Dean Simmons, an analyst with the Institute
of Defense Analyses, who in 1999 headed the group’s own study
of the topic. “Unfortunately, a consistently preferred alternative
did not emerge from these studies, nor did the studies consider
any of the new guided munitions that are now being developed by
The IDA report recommended the current change to 30 mm cannons,
but also suggested Maverick, Hellfire II and guided 2.75-inch rockets
as acceptable armaments for a future gunship.
Government labs and contractors are taking fresh looks at these
options. There are a couple existing weapons that SOCOM could choose,
adapted for the AC-130 by the Naval Surface Warfare Center at Dahlgren,
Researchers there have been investigating improvements to the AC-130’s
weapons systems for several years. Their latest attempt, according
to Dahlgren senior mechanical engineer Michael Canaday, entails
lobbing 120 mm mortar rounds from the platform, fired from a breach-loaded,
side-mounted gun. The AC-130 would have 360-degree coverage.
“We have completed the initial systems engineering analysis
and demonstrations,” Canaday said. “The next phase is
supporting the Air Force Special Operations Command, Air Force Research
Laboratory and SOCOM in the development of munitions alternatives
that will be part of their 2008 budget cycle.”
Planners at Dahlgren considered using a 105 mm round, but the 120
mm system required fewer modifications to make it aircraft-worthy,
Canaday said. While the munitions’ size and firing mechanism
have been decided, the warhead and guidance are still unresolved,
he added. “This work still needs to be done.”
SOCOM sees advantages in the mortar system developed by Canaday’s
“The 120 mm mortar offers a range of tactical flexibility
and capability over current gun systems and munitions,” said
Hoffmann. “Additionally, with the U.S. Army moving to the
M-395 Precision Guided Mortar Munition, the potential to leverage
already developed munitions is present. If this technology was developed,
it could decrease overall life cycle costs for weapons, munitions
The warhead types being examined speak to the prospective use of
the weapon in urban terrain. Penetration demonstrations against
steel and concrete have been conducted.
In test footage, the round appears as a large football with stabilizing
fins, sailing 900 feet per second into concrete at a 90-degree angle.
Upon impact, a large portion of the concrete disintegrates into
a cloud of debris.
Canaday noted that more wind tunnel testing is needed to factor
in the influence of crosswinds.
In another example of a future weapon system, Dahlgren in 2003
conducted a proof-of-concept demonstration at Arizona’s Yuma
Proving Ground using an armed unmanned aerial vehicle. The UAV was
launched and controlled from an airborne C-130.
“The UAV located a distant target and fired an air-to-surface
Hellfire launch against that target,” Canaday said. “The
target was destroyed, and its destruction was confirmed by the UAV.”
Funding for the weapons program is waiting for guidance from the
special operations community. Direction will be provided chiefly
through the fiscal year 2008 program objective memorandum, or POM.
The POM includes an analysis of future missions and the equipment
needed to complete them. “There is no program of record at
this time and until the POM process is complete, any future efforts
are to be determined,” Canaday said.
Even with the new capabilities, the AC-130 gunships appear to be
approaching obsolescence, and SOCOM is examining possible replacements.
“Evolving threat capabilities may preclude AC-130 employment
in many areas of the world within the next 10 to 20 years,”
said Hoffman. “Therefore, consideration must be given to fielding
a replacement system over the next 10 years.” To address the
shortfalls, the chief of staff of the Air Force directed the initiation
of an analysis of the next generation gunship. The results of this
study are leaning towards two alternative classes of aircraft, SOCOM
Preliminary results indicate two promising concepts—the “State-of-the-Art
Low Observable Manned Aircraft” and “State-of-the-Art
Unmanned Combat Aerial Vehicles.” Continuing studies will
determine which systems would be better at killing—and staying
alive—on the modern battlefield, Hoffman said.
In both alternatives, air-launched UAVs will provide off-board
sensor capabilities to boost the AC-130’s ability to track
targets in bad weather, between tall buildings and at the entrances
to caves, Hoffman added.
A standoff precision weapon, configured with either lethal or less-than-lethal
warheads, will enable either alternative to attack at ground ranges
out to 15 nautical miles.