It’s already been demonstrated that unmanned underwater vehicles
can sail from point A to point B and back. But the UUV development
programs currently under way have yet to yield useful war-fighting
capabilities for the Navy, said a senior service official. He is
hopeful, he said, that those technologies will come to fruition
in the near future.
“We have high school students who can demonstrate, build
and operate UUVs,” said Rear Admiral Michael Sharp, the Navy’s
program executive officer for mine and undersea warfare. “We
need to get beyond the fact that we have UUVs that can go around
and come back,” he told a conference organized by the Association
of Unmanned Vehicle Systems.
However, according to Navy Capt. John D. Lambert, the program manager
for unmanned underwater vehicles, the technology is progressing
rapidly. “It’s amazing what we can do with autonomy
and sensors,” he said. “But the problem is to make all
the programs talk to each other on a common interface.”
According to the Navy’s UUV master plan, released in 2001,
the fleet has little UUV-based capability today, “despite
the fact that there are literally hundreds of UUVs under development
or in operational use worldwide which have logged thousands of dive
hours.” The master plan cites lack of funding and coordination
as the two major reasons for not having more capabilities, although
there are many government agencies and contractors eager to work
on advancing the technology.
That was last year, however. The financial outlook for UUV programs
has improved since then. Sharp’s office has a budget of $1.5
billion over the next seven years. He said that only submarines
and UUV-related programs are funded. He said he would like to see
the Navy fund the integration of UUVs into the DD-X next-generation
surface combatant, a program slated to begin this year. “I
keep pushing for the DD-X and future ships to accommodate a family
of UUV and unmanned surface vehicles (USVs),” Sharp said.
The new surface combatants should be able to store and launch the
unmanned vehicles, said Sharp. He acknowledged this is still wishful
thinking, because there is no funded program to do this today.
According to the UUV master plan, launch and recovery of large
vehicles from a surface craft is a significant engineering challenge.
“Operations in high-sea states with or without divers would
be difficult, but not insurmountable,” said the report. “Cruiser/destroyer
type platforms are the least capable of taking on such a task, but
have the advantage of usually operating forward and possess relatively
low freeboard. Large deck ships are either not suited to the task,
have no room in the well deck or are not always operating forward.”
Sharp said that currently only small UUVs could be launched from
surface ships, but it would be problematic to do it with larger
ones, because of significant liability implications.
Nevertheless, said Sharp, the future Navy will need larger UUVs.
“The bigger the payload, the bigger the energy source, the
longer the duration and a lot of things get easier with larger UUVs,”
he said. There are conceptual designs, for example, of large UUVs
that carry small UUVs. “We have got to get there with the
large UUVs. There’s a lot of missions you can do with large
UUVs.”
He said that there are short-term efforts to demonstrate that a
UUV can operate from a Trident submarine. But Sharp is more concerned
about the long term—what vehicles actually can be produced.
“We know we can put a UUV on an SSGN and see what the consensus
is and put that into the budget.”
Sharp presented a future submarine concept where the outer hull
of the submarine is pockmarked with cavities to accommodate UUVs
or external weapons. He said he wants to see some of the payload
outside the actual boundary of the hull. “I am expecting the
Virginia class [attack submarine] will move towards the capability,”
he said. “It just takes some work of shaping the vehicle differently.”
He predicted it would take a decade to bring those concepts from
the lab to the fleet.
Multimission Vehicle
Sharp warned that he did not expect to have 10 different UUVs to
do 10 different missions. “We want one UUV to do multiple
missions,” he said.
Lambert stressed that the Navy wants flexible UUVs that can operate
both from surface ships and submarines. “We want to have a
mission reconfigurable UUV,” he said. The core of the master
plan is the development of UUVs that can be adjusted to various
missions. “With common functional modules and standardized
internal interfaces, great flexibility and transition between systems
can be achieved,” the report said. “Standardization
of module sizes is recommended: small 6-12 inch diameter modules
and larger, nominally 21-inch diameter modules. These standards
will form the foundation for a variety of UUV sizes and capabilities.”
One promising system is the mini modular UUV, that would provide
communications and navigation capabilities. “As these standard
modules are developed, payload modules will be developed on a parallel
path, thus insuring system compatibility,” the master plan
said. “These payload modules will include specific packages
such as oceanographic sensors, communication links and navigation
systems.”
A tactical modular UUV would address the Navy’s requirements
for maritime reconnaissance, said the report. The first step with
these UUVs would be the standardization of module size and contents,
“with special attention paid to those capabilities needed
by a system vehicle as a whole,” said the master plan. “The
approach can lead to an initial maritime reconnaissance capability
by fiscal year 2007.”
Before any modular UUVs are developed, however, the vehicle’s
capabilities to operate autonomously are among the most urgent problems
that need to be worked out. The robotic capability of UUVs today
would not be advanced enough to make them go after submarines autonomously,
said Sharp. “I don’t think our UUVs would be very good
at that today.” He said that a fairly “large leap in
technology” would be required for the track-and-trail capability.
That capability would allow a UUV to go and find and enemy sub,
identify it as such and figure out what it is doing and complete
the mission, said Sharp.
According to the UUV master plan, the “ultimate submarine
track-and-trail capability” could be provided by a large UUV
housing several sensor suites.
“The sensor suite would likely include: a passive acoustics
suite; a non-acoustic suite, which is used for the initial detection
and as an aid in maintaining trail, and a short range, very high
frequency, low probability of intercept sonar for obstacle avoidance
and close tracking,” said the report. The UUV also would have
extensive communications capabilities, including satellite links.
Communication and real-time connectivity are some of the major
shortfalls in current UUVs, said Sharp. “If they are going
to operate submerged, the ability to get information from them in
real time is limited,” he said. “With a small vehicle
and a small antenna, your information relay is going to be low.”
Fiber optics system should be explored, Sharp suggested. “When
you try to get real time, you have a trade-off,” he warned.
“You really want to send the raw sensor and sonar data and
that requires impossibly large bandwidth in any of these scenarios.”
In his opinion, the vehicle needs to send back useful tactical information
rather than just send back raw data. That will require immense improvements
in computational power and intelligence-agent software.
Officials agreed that, in general, the technologies that need further
development in order for UUVs to become useful military vehicles
are energy sources, real-time connectivity, automatic target recognition,
autonomous navigation and sensor payloads.
The batteries often used in UUVs are lithium batteries, which have
a short life and do not allow for more than a few hours of operation.
“I would like to see the UUVs when we can operate in days
rather than hours,” Sharp said. “The real concept is
to drop the UUV and let it do its thing and then come back and recover
it.”
One of the alternatives for energy would be diesel fuel, like in
the Remote Minehunting System, developed by Lockheed Martin Corp.,
for use on Aegis destroyers. The company recently received a $130
million contract to continue the development of RMS and deliver
two prototypes in 2004.
Another countermine program, the Long-Term Mine Reconnaissance
System, also is an unmanned vehicle that operates on lithium batteries.
The contractor, Boeing, plans to test the system later this year,
said Margret Calomino, the program manager for un-manned underwater
vehicle systems.
“LMRS is a system, not just one vehicle,” she said.
The vehicle that is submerged under water is 21 inches in diameter
and 240 inches in length. It weighs 2,800 pounds and operates at
depths of 1,500 feet. Its maximum speed is 7 knots. The launch/recovery
arm assembly began in January 2002, said Calomino. LMRS is scheduled
to be operational in 2004, said Lambert.
The Multi-Mission Reconfigurable UUV (MRUUV) is an evolution on
the LMRS. The concept will be studied until 2003, said Lambert.
After that, the design work will start. The payload development
will start in fiscal year 2005 and is supposed to end in 2009. According
to Sharp, the large diameter MRUUV should have robust sensor capabilities
for reconnaissance and surveillance, the ability to launch missiles
and drones and to track enemy submarines.
Rear Adm. Malcolm Fages, the Navy’s director of undersea
warfare, wrote that the MRUUV could be used to deploy data collection
assets, like periscopes, antennae, or acoustic sensors that can
be placed up rivers and in waters too shallow for submarine operations.
“UUVs could also be used in concert with the Advanced Deployable
System (ADS) for submarine track and trail,” he wrote. “An
ADS trip-wire detection could be used to cue a UUV handoff, or the
MRUUV might service an ADS field, downloading data and uploading
search parameters.
“UUV’s could be employed to sample for evidence of
WMD (weapons of mass destruction) precursors or relay launch orders
to pre-staged weapon pods for land-attack strikes. The possibilities
opened up by building covert, autonomous, vehicles with modular
payload capacities are essentially unlimited.”