It's an 'Osprey' We're Not Afraid to Fly

OK -- that's not fair. This little guy has been flying, and it's doing well. The Bell Eagle Eye Tiltrotor UAV (BEET-U? no; it's the "TR911D") is a new concept in what Bell hopes to be the next generation of ship-based surveillance machinery.

The single-engine (PW200-55) baby was originally presented to the Navy, about ten years ago, but lost the competition to what is now the Fire Scout. Now, Bell is working on the Coast Guard for deepwater deployment; and there's talk that Lockheed Martin may someday become part of the mix, as well.

The Eagle Eye first flew in low tethered hover in 1989, according to Bell's Brent Achttien, whom we met at the Association for Unmanned Vehicle Systems International (AUVSI) exhibition, which opens today in Orlando (FL).  After five years of on-and-off development, the project had accumulated 26 flight hours, and was moved to Yuma (AZ), where it languished, as resources were deployed on other projects. In 1998, Bell conducted a 50+ hour test regimen over 90 days, without a single mishap.

The props are small, but still, vertical takeoffs and landings are the only way to fly. This fully-autonomous machine can take off, rise (to about 100 feet), transition to horizontal flight, fly its mission, and return, hovering and then lowering itself at something less than 10 feet per second (vertical) into ground effect (the last five feet or so), whence it lands.

Even though there will never be a human on board, the Bell Eagle Eye has full dual redundancy on all controls (even throttle). There is also an override system, run by a human pilot, through Futaba controls. This system is used to start the engine, and to take the machine to its initial 100-foot hover, from where it transitions on its own to horizontal flight, and completes its mission, all under the influence of GPS, of course.

"It's small and quiet, too," said Jerry Massey, who is another of Bell's "Wizards of Ft Worth," as he helped with the display setup. It's small enough to fly from a Coast Guard 270-class ship, the smallest practical Coast Guard platform for the Eagle Eye, in Bell's estimation.

To get an idea of just how small this machine is, note that its wingspan is just over 15 feet; instead of the 38-footers of the Osprey, it's carrying three-bladed 9.5-foot rotors. Though it really likes a 36-foot-square "airstrip" for operations, it's extremely compact; and its nose, tail, and wings all fold.

Just six people can operate as many as four Eagle Eyes, simultaneously -- and training is, as you would expect, 'way simpler (and quicker and cheaper) than with anything like a manned equivalent.

What'll It Do?

So far, the twin-tail Eagle Eye has demonstrated its capabilities in low flight, vertical flight, hover, and transition. It has navigated and returned to its exact takeoff point, autonomously. It has also flown at density altitudes of 15,000 feet (Bell says it'll fly OK at 20,000), where it has demonstrated level flight at 200 knots.

Currently, its useful payload is about 200 pounds. With a representative fuel load, she'll stay in the air just under four hours. Maintenance, unlike most rotorcraft, takes a tiny bit less than an hour, for each hour of flight.

We'll keep you informed, as this little composite ship performs more air trials...

Anything Else New?

While it's not a UAV, it's an interesting Bell development. Would anyone like to see a "Quad Tiltrotor?" It's a two-winged tiltrotor, with four engines -- get this -- it's roughly the size, and has the carrying capacity, of a C-130!  No -- we don't have a photo of that one. It's in the concept stage.

FMI: www.bellhelicopter.com/products/tiltRotor/eagleEye