Integrated Product Team to Design/Build/Fly Full Scale Tiltrotor UAV in One Year

Ya gotta admire the folks who take on the BIG challenges... Following what Bell characterizes as the "remarkable success" of their 7/8 scale Bell Eagle Eye Tiltrotor UAV prototype (shown below, right), Bell CEO Mike Redenbaugh has announced a major new effort to design, build and fly a new full scale Bell Eagle Eye by November 1, 2004. Speaking to a handpicked team of about 40 aerospace engineers and manufacturing and production experts, Mr. Redenbaugh said, "there is a strong worldwide interest in the Bell Eagle Eye and we owe it to our customers to develop this full scale prototype to demonstrate the full capacity of this great tiltrotor product."

Bell's Director of UAV Programs Robert Dompka explained that while the one-year to flight status goal is a challenge, "Bell has a great history of tackling ambitious projects with teams of dedicated employees; such as the great effort to produce the first Cobra attack helicopter back in the mid-1960s, and more recently the development of the Bell 407 commercial helicopter in less than one year."

The Bell Eagle Eye tiltrotor Tactical VTOL unmanned aerial vehicle (UAV) is the greatest leap in UAV technology in the past half century. Traditionally UAVs have been small fixed wing aircraft requiring either a runway or netting for retrieval. Normally runways are unavailable in the field and netting has proven to be a very hazardous form of UAV retrieval aboard ship often resulting in serious damage to or destruction of the aircraft and very expensive.

Helicopters have the advantage of being able to takeoff and land anywhere. However, helicopter UAVs do not have the speed and range of fixed-wing UAV aircraft. Further, small short coupled tail rotor aircraft may not be stable when going through the burble experienced with landing on Navy Surface Combatants. The Bell Eagle Eye is the perfect solution. With its rotors in the vertical position, the Bell Eagle Eye can takeoff, hover and land like a traditional rotary wing aircraft. By tilting its rotors to the horizontal position the Bell Eagle Eye can fly with the high speed and range of a turbo-prop fixed wing airplane. Also, the counter rotating design provides improved stability through the burble.

The Bell Eagle Eye Tactical VTOL UAV Demonstrator flew under NAVAIR contract N00019-98-C-0051, VTOL UAV Demonstration Program at Yuma Proving Ground, Ariz. The contract required 50 hours of land based flight tests to evaluate the performance and maturity of the aircraft and control system. The Eagle Eye Demonstrator aircraft was the first to finish the 50-hour Land Based Flight Test Task.

In less than 90 days after its first flight on March 6, 1998, the single Eagle Eye Demonstrator flew 55.5 hours. It made 43 landings, 42 of which were within 15 minutes of the intended take-off time and it completed tests that have expanded the aircraft's envelope and proven its advertised performance and technology maturity claims. During the tests, the envelope was expanded to over 14,600 feet and more than 200 knots True Air Speed (TAS) in level cruise flight; while carrying 210 pounds of payload plus mission fuel, exceeding the objectives substantially. Performance in the "best endurance mission was more than 1.7 hours on station. And in the "best range" mission, the aircraft flew more than 315 nautical miles. Real time target imagery was provided during the flights.

Both the aircraft and ground control station performed flawlessly, getting up and going to work for every scheduled flight in a regimented 2-hour range test period. Maintenance requirements (other than pre-flight checks) were almost nonexistent.

The Eagle Eye Demonstrator executed all applicable demonstration objectives, and expanded the aircraft's flight envelope substantially. Capabilities demonstrated included:

• Routine VTOL take-off and landings to a 24' helicopter landing spot
• A launch and recovery accuracy better than the required 9.8'
• Automated hover and landing in winds gusting to 32 knots
• Stable hover out of ground effect at 1100 MSL in 95 temperatures while carrying 210 pounds of payload and 350 pounds of fuel
• Recovery at take-off gross weight
• The ability to fly (cruise) at speeds between 0 and 150 knots. (202 knots TAS cruise achieved with less than 90% power)
• Cruise at 14,600' with a 200 pound payload (aircraft design limit >20,000 ft)

PMA-263 assessed the contractor's ability to provide the required performance data. Bell Helicopter's Eagle Eye Demonstrator was rated at 95%. The next best was 60%. The best news seems to be that providing this capability to the military services is a relatively low cost, low risk process since most of the components are off-the-shelf man-rated helicopter parts.

Officials for Integrated Coast Guard Systems (ICGS) announced in February, 2003, that the Bell Eagle Eye was selected for the Unmanned Aerial Vehicle (VUAV) portion of the U.S. Coast Guard's Integrated Deepwater System contract. The Coast Guard's Integrated Deepwater System is a critical multi-year program to modernize and replace aging ships and aircraft, and improve command and control and logistics systems. Bell Helicopter is a subcontractor to Lockheed Martin Naval Electronics & Surveillance Systems, who is a major contractor to ICGS. Under this award, Bell Helicopter is scheduled to begin delivering the Bell Eagle Eye aircraft with a First Unit Equipped (FUE) date of 2006. The total anticipated contract is valued at over $1 billion over the life of the program.

Bell, a leader in Systems Integration developed the state-of-the-art, fully integrated redundant flight control system which boasts of highly automated flight control and built-in test software, as well as fully integrated surface mount circuitry.

Using tiltrotor technology, the Bell Eagle Eye System also adds the dimension of speed flexibility to the usual UAV performance parameters. With its rotors tilted forward it can cruise at speeds over 200 knots reducing time to get to an operational area, find moving targets 80-110 nautical miles away in minutes and be easily in-flight re-tasked for another mission. Conversely, it can loiter over a target 100 nm away for four hours. In the hover mode the Bell Eagle Eye can operate from confined spaces, launch and recover automatically from small ships.

The Bell Eagle Eye offers the Coast Guard and other sea service users numerous performance capabilities simply not available in helicopter drones.

FMI: www.textron.com