Ran in The Rocketeer on 25 June 1998

UCAVs may find niche in 21st Century

By Cliff Lawson
China Lake, CA-At first glance, this seems like the most sensible idea imaginable. Build an aircraft around a payload, instead of a pilot. Design the craft for up to 30 gs lateral acceleration, so that it can evade even the most capable air-intercept missiles and easily engage and destroy any manned aircraft. Fill the plane up with weapons, send it into the fiercest threat environments to attack the enemy, then bring it home. Reload, and do it again.

But in the ever-changing world of battlefield dynamics and warfighting technology, things are never that simple.

A multifaceted issue

In fact, the concepts, technologies and operational applications involved in the Uninhabited Air Combat Vehicle (UCAV) are remarkably complex. That's why NAWCWPNS has established a UCAV Strategic Thrust, which is currently being conducted in partnership with NAWCAD.

Scientists, engineers and analysts here and at Patuxent River are trying to determine the potential applications and operational benefits of UCAVs and, if a beneficial role is defined, to help the Navy develop and integrate these unusual weapons into the 21st century battlespace. "We're looking at a possible role for UCAVs as a complement to, rather than a replacement for, manned aircraft," says Dr. John Fischer, deputy leader of the UCAV Strategic Thrust. "We're asking `Is there a mission for UCAVs that isn't filled by current or planned weapons?'"

UCAVs versus UAVs

Aircraft without pilots are not new. In the Vietnam conflict, a thousand Lightning Bugs, remotely piloted vehicles produced by the Ryan Aeronautical Co., flew more than 3,000 reconnaissance sorties. These missions - some of them up to 1,400 nautical miles round trip - covered extremely hazardous territory. The Lightning Bugs saved the lives of countless manned-aircraft pilots and freed them for other missions.

Such unmanned reconnaissance vehicles, as well as the full-scale aerial targets (FSATs) that NAWCWPNS has been involved with since the early 1950s, are known as unmanned air vehicles, or UAVs. UAVs are already in widespread use in U.S. and foreign military services. They are also used by the private sector in roles such as crop dusting and weather research.

A critical difference exists, however, between a UAV and a UCAV. That difference is the weapons. If a reconnaissance UAV takes a photo of the wrong area, little harm is done. But if a UCAV expends its ordnance on the wrong target, the consequence can be catastrophic. Fischer says, "The fleet has made it clear to us. The possibility of blue-on-blue engagements with UCAVs must be absolutely zero."

A convergence of technologies

UCAVs are at the juncture of three converging trends, according to operations research analyst George Palfalvy. First, aircraft are becoming more autonomous and their computers are taking over more of the functions of targeting and weapons delivery. At the same time, weapons such as the Tomahawk cruise missile are becoming more sophisticated and capable of functions, such as target and aimpoint selection, that heretofore belonged to the delivery platform. Finally, UAVs are achieving ever-higher performance levels as new technology is incorporated into their design.

"The UCAV draws on all three of these trends," says Palfalvy. "The first actual UCAV might be a weapon system integrated with a UAV. But by the second or third generation, the UCAV will be its own distinct product."

Palfalvy's view is shared by Dr. Robert Schwartz who, along with physicist Terry Rogers, conducted a study of the Joint Semi-Autonomous Air Weapon System (JSAAWS). "We don't want an aircraft that just has the pilot taken out," says Schwartz. "But we also don't want to just put weapons on an existing UAV."

UCAV research at NAWCWPNS

In 1992, Palfalvy and Dr. David Andes, who was then researching artificial intelligence, were funded by ONR to conduct a feasibility study of building an unmanned, armed, reusable, highly maneuverable and mostly autonomous aerial weapon system. They called the system the Highly Maneuverable Lethal Vehicle (HMLV).

The HMLV program lasted four years. Palfalvy and Andes concluded that, while there was no current requirement for a UCAV, a time could come when combined fleets of UCAVs and manned aircraft would work in concert to achieve mission goals. The study indicated that a cost savings of up to 70 percent over manned aircraft might be realized over a 20-year period.

The researchers urged continued investigations into UCAV technology. They also suggested that some less-sophisticated UCAVs be built, demonstrated and put in the hands of the warfighters. In that manner, the operational units could begin to develop techniques for incorporating UCAVs with other assets.

Palfalvy and Andes were also the organizers of the nation's first-ever UCAV Conference, held at NAWCWPNS in January 1997. "That was the coming out party for UCAVs," says Fischer. The conference, keynoted by RAdm. McGinn, CNO N88, brought together more than 150 experts from government and industry to spend three days discussing UCAV technologies and applications.

In the 1996-97 JSAAWS study, Schwartz and Rogers looked at the concept of a low-cost, tactical UCAV. Their efforts laid a strong groundwork for future cooperative efforts with other naval aviation participants and established UCAV contacts throughout the operational community. The study resulted in the development of candidate mission roles and the generation of notional concepts-of-operations and notional UCAV concepts.

How much autonomy is enough?

One issue that generates debate in the UCAV community is the degree of autonomy that a UCAV should be permitted. At one extreme is complete operator control over the UCAV. A pilot sitting in a room far from the battle would "fly" the vehicle through its mission. At the other extreme - which Andes estimates is probably 50 years down the road - is total UCAV autonomy. "Send it off and say, `The target's over there,'" explains Andes. "`Go kill it.'"

With minimal UCAV autonomy, a continuous bidirectional communications/data link between the UCAV and the controller is required. Making a survivable, jam-proof link that can survive the heat of battle poses significant technological challenges.

However, as the degree of UCAV autonomy increases, the sophistication of the sensing and decision-making functions on board the UCAV must also increase. At the same time, the need for bidirectional communications and data-transfer decreases. Andes sums it up: "The more thinking on the vehicle, the less bandwidth required."

Most researchers appear to agree that the ideal level of autonomy is one that allows the vehicle to perform almost all functions without human intervention - that is, no joystick - but ensures that a human controller always retains final firing authority.

Inter-division and inter-service cooperation

The single largest effort involving UCAVs is a $140 million joint Air Force and Defense Advanced Research Projects Agency (DARPA) project. Fischer sees this as an advancement for the Navy as well. "The Air Force has been very willing to share the results of their work," he notes.

To avoid duplication of other service's efforts, the Weapons Division and Aircraft Division are concentrating on the Navy's role in UCAVs. "Our focus is Navy-unique requirements, such as ship launch and recovery," explains Fischer. The NAWC work is being carried out through the UCAV Advanced Development Project Office, directed by the Aircraft Division's Cdr. Osa Fitch, with deputies Julietta Booz at the Aircraft Division and Dr. John Fischer at the Weapons Division.

NAWCWPNS UCAV Strategic Thrust builds on the Division's long experience with FSATs, with weapon design and with weapon/aircraft integration. The thrust also draws on divisional expertise in such areas as operations and systems analysis (which can help define and clearly articulate a Navy role for UCAVs) and artificial intelligence (which has the potential to increase UCAV decision-making capability and autonomy).

Not long ago, the UCAV was a curious scheme that few but the most adventurous thinkers took seriously. Today, the Weapons and Aircraft divisions are working as a team to address the practical issues of UCAV applications and technology. The results of these efforts will determine the role of UCAVs in the Navy of tomorrow.