Are Modernized Ground Effect Vehicles the Answer to Greener Flying?

After reading our recent post "Hydrogen-Fueled Planes Could Meet One-Third of Air Travel Demands by 2050," a commenter floated what at first sounded like a wild idea:

"I do see nuke-powered Seaplanes like ground effect ships for transocean travel which likely made many of your jaws drop. There is some improved tech allowing very light portable inherently safe pebble bed reactors may be available in 5 yrs in the 1-5MW range. And GES are good at carrying loads so a 300mph travel with sleeper, bars, etc can easily be done."

Now forgive me a flight of fancy, but this might not be as silly as it sounds. It reminded me of the amazing ekranoplans (Russian for "sheet effect") designed in the former Soviet Union (USSR) in the '60s. These were ground effect vehicles (GEVs) designed to carry men and missiles at high speed just above the water. The A-90 Orlyonok in the image above was capable of carrying 150 people and could go 250 mph for up to 930 miles. It could also fly like an airplane, although it was much less efficient. The Lun-Class shown below could go 340 mph for 1,200 miles. (See amazing photos of it inside and out here.)

GEVs are like airplanes in that they have wings that produce lift when there is forward motion. The difference, according to Flite Test, is they take advantage of the ground effect, which is "the result of the relationship between a lifting wing and fixed surface located beneath it." Flite Test explains: "As air is directed downwards and pressurized by the wing, the fixed surface acts as a boundary which traps the air. The result of this is a 'cushion' of air." This also reduces drag, so it can be much more efficient than a conventional plane and carry heavier loads.

The A-90 Orlyonok isn't going to get Treehugger contributor Sami Grover home to see mom in the United Kingdom, but I wondered if there had been any progress in developing more modern GEVs. It turns out Boeing proposed the Pelican, a GEV, to the U.S. military in 2002. It was patented in 2005 and patents were still being issued in 2009.

The Pelican is huge. According to a 2002 Boeing press release:

"Dwarfing all previous flying giants, the Pelican, a high-capacity cargo plane concept currently being studied by Boeing Phantom Works, would stretch more than the length of a U.S. football field and have a wingspan of 500 feet and a wing area of more than an acre. It would have almost twice the external dimensions of the world's current largest aircraft, the Russian An225, and could transport five times its payload, up to 1,400 tons of cargo."

It was designed to be capable of flying like an airplane, although that was not nearly as efficient.

"Designed primarily for long-range, transoceanic transport, the Pelican would fly as low as 20 feet above the sea, taking advantage of an aerodynamic phenomenon that reduces drag and fuel burn. Over land, it would fly at altitudes of 20,000 feet or higher. Operating only from ordinary paved runways, the Pelican would use 38 fuselage-mounted landing gears with a total of 76 tires to distribute its weight."

According to program manager Blaine Rawdon, "It is much faster than ships at a fraction of the operational cost of current airplanes. This will be attractive to commercial and military operators who desire speed, worldwide range and high throughput."

Boeing said the ground effect occurs when "the wing downwash angle and tip vortices are suppressed, resulting in a major drag reduction and outstanding cruise efficiency."

"It's an effect that provides extraordinary range and efficiency," John Skorupa, then Boeing's senior manager of strategic development, said. "With a payload of 1.5 million pounds, the Pelican could fly 10,000 nautical miles over water and 6,500 nautical miles over land."

Those numbers work out to a 54% increase in efficiency due to the ground effect, so you get a lot further on a gallon of fuel.

The Pelican was powered by eight turboprop engines, each with an output of 60,000 kilowatts, spinning propellers that are 50 feet in diameter.

In freight configuration, the patents show it holding 200 shipping containers. In passenger configuration, it could hold 3,000 people.

That was all in 2002. The Pelican never got off the ground and was quietly shelved, but fast-forward twenty years and it might be time to look at it again. According to aviation expert Dan Rutherford, who's the program director for the International Council on Clean Transportation, the liquid hydrogen-powered plane described in our original post "won’t get you over the pond in this configuration without a stop in say Greenland.” But the Boeing Pelican has enough capacity to hold as much liquid hydrogen as you need. You might even be able to fill it with big batteries. And because it flies between 20 and 50 feet off the water, there is none of that pesky radiative forcing that you get from high-fliers.

The Pelican is slow compared to jets because the air is so much thicker down there but still goes  240 nautical mph (276 mph or 444 kph). A trip between New York and London is 3,000 nautical miles so the trip would take close to 11 hours; Los Angeles to Sydney would take 27 hours. But as our commenter suggests, there is enough capacity and room to put in sleepers and bars.

Here at Treehugger, I usually stay away from pie-in-the-sky schemes, and this is certainly one of them. But in 2002 Boeing said it could have the Pelican flying in 10 years. Perhaps building a hydrogen- or battery-powered Boeing Pelican is not such a silly idea. I am not so sure about our commenter's suggestion of nuclear power.