“You get paid for this?”

The question sounds familiar to David Eichstedt, one of a half-dozen or so engineers working on Desert Hawk at Lockheed Martin Advanced Development Programs in Palmdale, California. However, the occasional ribbing from coworkers does not detract from the project. “The airplane may look like a toy, but it performs a serious mission,” says Eichstedt.

That mission is force protection. And this toy-like, yet very sophisticated, device performs it very well. So well, in fact, that the Desert Hawk was the US Air Force’s nominee for the 2002 Collier Trophy.

The Desert Hawk is the flying portion of a larger aerial reconnaissance system formally called the Force Protection Airborne Surveillance System, or FPASS for short. The aircraft, powered by an electric motor, acts as a flying sentry. It quietly surveys large areas with its three tiny internally mounted video cameras. A one-pound payload capability also accommodates an infrared imaging system, which provides night vision. A transmitter on the Desert Hawk sends video images directly to a ground station in real time. From there, the images can be shared over existing networks.

FPASS is different from all other small UAV systems. “Operators basically launch and watch,” Eichstedt explains. “The system has no joystick and requires no pilot. Flight paths are set on a laptop control screen. The airplane navigates autonomously. An operator can change the flight path in flight, however. An ‘orbit here now’ button on the computer screen immediately sends the Desert Hawk into a circular pattern and keeps the cameras pointed at the center of the orbit.”

Origins And Evolution

FPASS traces its origins to a 1996 Defense Advanced Research Projects Agency program called Micro Air Vehicle. The goal of the DARPA MAV program was to develop a reconnaissance airplane that has no dimension greater than six inches. The vehicles had to be able to conduct realtime imaging, have ranges of up to ten kilometers, and speeds up to thirty miles per hour for missions ranging from twenty minutes to two hours. Several micro UAVs resulted, including the MicroStar from Lockheed Martin and the Black Widow from AeroVironment.

Lockheed Martin engineers learned large from these minuscule beginnings. “We found that tiny vehicles get tossed around in the wind,” notes Eichstedt. “Image quality suffers. So, we built a series of larger vehicles to determine an optimum size.”

The six-inch MicroStar begat platforms of increasing wingspans of nine, fifteen, and twenty-four inches. “We found that the bigger the vehicle, the greater its operational utility,” says Eichstedt. “Larger wingspans can, of course, carry more weight. More importantly, the aerodynamic damping characteristics create a much more stable platform as well. The minimum size for a stable operational vehicle has a wing span of about two feet.”

The DARPA MAV program did not spawn any production decisions, but Lockheed Martin continued developing MAV technology, including an autopilot system.

Surfing The Net

Many of the technologies developed for MAV were applied to the FPASS program by chance when a Skunk Works engineer ran across a request for information in 2001. “Joe Wurts, a top configuration designer who happens to be a world champion radio-control glider pilot, was out surfing an Air Force opportunities website and noticed a request for information for a small, inexpensive UAV,” recounts Eichstedt.

Wurts and a small group of engineers replied to the request with information they had developed in their own MAV studies. The Air Force asked for a flying demonstration based the response.

During the demonstration, one of the USAF evaluators asked the Lockheed Martin team to redirect the airplane to orbit a cluster of static airplanes he had spotted on the laptop display. After a simple keyboard command, the UAV began orbiting the parked aircraft and sent back clear and steady video. “The system did a great job of retasking and keeping the area of interest in sight,” says Eichstedt. “The evaluators realized our system was a step beyond other systems. None of the others approach the autonomy and ease of use we’ve achieved.”

Furthermore, the Skunk Works was the only team that could deliver the system in a short timeframe. The Air Force signed a contract letter in late February 2002. Lockheed Martin delivered the first two systems 127 days later to Electronic Systems Center at Hanscom AFB in Massachusetts, which is responsible for force protection for USAF forces. Six more systems were delivered in October.

Each system consists of six airplanes, a ground control station, a remote viewing terminal, and a field support kit that has spare items, such as servos, motors, patch kits, battery chargers, and the bungee launcher. The ground control station includes a commercially available ruggedized laptop. In fact, the program uses as much off-the-shelf and non-developmental hardware as possible. FPASS is shipped in ruggedized and water-proof shipping containers. A complete system takes up a space of only eight by eight by four feet and weighs about 520 pounds.

The Desert Hawk itself has a wingspan of fifty-two inches and measures thirty-four inches from nose to tail. Payload and the flight duration requirements set the size. The engine and propeller are rear-mounted to soften landings. The Styrofoam-like material is mold-injected expanded polypropylene foam, which is more durable than extruded polystyrene (better known by its brand name of Styrofoam). Kevlar skids on the nose and tail improve durability as well. The sensors are carried in the middle of the fuselage. A notched area in the lower fuselage provides operating space for the color or infrared cameras. GPS and other antennas are mounted on the wings.

The Desert Hawk is launched with a long bungee cord. Once airborne, the UAV executes its flight path and feeds data back to the operator at a mobile ground station. In addition to the ability to change the vehicle’s flight path with the click of a mouse, the operator can mark targets with GPS coordinate and record the entire flight on mini-DV camcorder tape. A single system as delivered can support 24/7 flight operations.

“We can train enlisted personnel to operate the system in about one week,” notes Eichstedt. “Since the system doesn’t need a pilot in the loop, operators don’t have to learn how to fly a radio-controlled airplane, which is an acquired skill. Since we aren’t using the imagery from the airplane to fly it, operators can focus their attention on finding targets.”

Future

The success of the Desert Hawk spurred interest from a variety of potential customers. “We’ve demonstrated the system for several agencies that fall under the new Department of Homeland Defense,” notes Kent Burns, the FPASS program manager for Lockheed Martin. “We see a large market for the system.” Other potential customers include local police forces and other security agencies that monitor pipelines, aqueducts, and harbors.

Engineers in Palmdale are looking at ways to improve the system. “We can drive out a lot of the cost by moving to a mass manufacturing environment,” Burns continues. “We’re monitoring improvements in battery and fuel cell technology as well as sensor technology. Software improvements will allow multiple UAVs to work together so the system can cover a wider path of ground and find targets faster.”

Collier Candidate

While FPASS didn’t win the 2002 Collier Trophy (the Sikorsky S-92 helicopter did), being the US Air Force’s nomination for that prestigious award was an honor in itself. “We didn’t really expect to win,” Eichstedt admits. “But having our customer nominate us is a huge compliment.

“We have received attention far greater than the contract value,” Eichstedt continues. “Part of that attention can be attributed to the FPASS’s unclassified status. We happen to be one of the few programs the company can talk about in public. On the other hand, we delivered a capable system in a very short timeframe. We are also the only fully operational, totally autonomous UAV. We really do have something special here”.

Burns, Eichstedt, and others working on FPASS didn’t need a Collier Trophy for motivation. “The program was conducted under a letter of urgent and compelling need from the customer,” Eichstedt explains. “They had to get these systems in the field as soon as possible to protect American forces and personnel. Patriotic pride motivated the team members to put in an extra effort to get the system completed as soon as possible. Everyone understood that FPASS would directly protect American lives. The technology itself is fun. The work of bringing together the components and suppliers to meet the specs and aggressive schedule is somewhat stressful. But knowing that we might be saving some lives is the real payoff.”

Eric Hehs is the editor of Code One.