Monster at 20 ft.

Flying the Pelican will be a bit more complex than piloting conventional aircraft. Before a flight, crews and mission planners will use radar and photo imagery from satellites to check the weather en route, in order to exploit tailwinds and avoid storms. If the straight-line route lies across a landmass, the crew can decide whether it is better to fly around it or jump over it. Even if the ocean is raging, the engineers are confident that the airplane should be able to cruise at very low altitudes most of the time. "We grow up watching Victory at Sea on television or The Perfect Storm at the movies, and we naturally have the view of the ocean being tumultuous and violent," Rawdon says. "But the majority of the time it's relatively quiet, serene and flat."




But Hooker, the former DIA analyst, thinks that even over a quiet ocean, the Pelican will be a handful. "The uglier it is in free air, the better it is in ground effect, and vice versa," he cautions, meaning that Boeing's choice of a long, thin wingspan over a short, stumpy one may make the Pelican excessively hard to control, giving it a spongy, undulating ride. One lesson from the ekranoplans, he explains, is that the vortex under the wing acts like a spring, yielding resistance between the airplane and the surface. With a stubby ekranoplan wing, the vortex is a stiff spring like that of a racing car. A long-winged WIG floats like a Cadillac, making control more complex.




But Boeing is anticipating some complicated maneuvering, so the controls will be highly automated; nobody is going to hand-fly the monster at 300 mph and 50 feet up. High-resolution radar will scan the sea ahead for ships, and the automatic control system will either turn to avoid them or lift the big airplane over them. On the ground, the challenge will be steering the Pelican-with 76 wheels arrayed centipede-like under its body-around taxiways designed for airplanes half its size.




Hooker will watch with interest as Boeing continues its investigations in this area. He led a design study for a large ekranoplan, which included a look at whether a several-thousand-ton vehicle could use conventional airports. "It's not the runway," he says. "Most airports are located on high water tables, and the taxiways and aprons are built on round gravel." A giant vehicle, he says, sets up a long, gentle seismic wave. "First you get cracks in the toilets in the terminal building and after a few months, things start to fall down."




Will the Pelican fly, or join so many WIG concepts in short chapters of the aviation history books? Fortunately, Pelican should not require any breakthroughs in basic technologies, such as structures or propulsion. The next step, the engineers say, would be a three-year program to build and test a subscale Pelican. This wouldn't be a small airplane-it will need to be big enough to explore the ground effect over calm water-but it would be a simple one, using off-the-shelf technology. If the Army's mobility study shows that the Pelican could be useful, work could start late this year or in early 2004.