 Image courtesy Worldwide Aeros Corp. The Aeroscraft |
Passenger travel and shipping by airship died out in the late 1930s, after the infamous Hindenburg disaster. Since then, lighter-than-air craft have been used mainly for advertising or to provide aerial views for television cameras. In recent years, several companies have been introducing safer, more efficient airships to the world. These companies include the Zeppelin Company, makers of the Hindenburg, and Worldwide Aeros Corp, designers of the Aeroscraft.
A lighter-than-air craft, such as an airship (or blimp), is filled with a gas, such as helium or hydrogen, which provides buoyancy. Buoyancy is the effect of something rising up in relation to a heavier substance surrounding it. Air is lighter than water, so if you fill an inflatable ball with air, it will float in a swimming pool. The same thing happens with helium or hydrogen -- they're both lighter than air. (To learn more about how blimps fly, check out How Blimps Work.) A regular airplane is much heavier than air, so lift must be provided by some other means. Lift is a force on a wing immersed in a moving fluid (in this case, air), and it acts perpendicular to the flow of the fluid. When the plane moves through the air at sufficient speed, the deflection of air creates lift. This is a very basic explanation; check out How Airplanes Work for more detail about how lift is created.
 Image courtesy Worldwide Aeros Corp. The major parts of the Aeroscraft |
The Aeroscraft combines elements of a lighter-than-air craft with those of an airplane. It holds 14 million cubic feet of helium, which negates about 60 percent of the craft's weight [ref]. When the Aeroscraft is at cruising speed, its aerodynamic shape, as well as canards (forward fins) and empennages (aft, or rear fins), provide the remaining lift. That's pretty impressive when you consider the Aeroscraft's size: 165 feet high, 244 feet wide and 647 feet long. That's about as long as two football fields. It will carry up to 400 tons of cargo over a range of 6,000 miles. With a top speed of 174 mph, it will be able to cross the U.S. in about 18 hours [ref].
Operating the Aeroscraft
The Aeroscraft can take off and land vertically using six turbofan jet engines, thanks to an emergent technology called Dynamic Buoyancy Management. This capability will allow it to fly to and from areas without an extensive transportation infrastructure. Once the craft reaches cruising altitude (around 8,000 feet), giant aft propellers will move it forward, and the Aeroscraft's aerodynamic shape will generate enough lift to keep it in the air. Hydrogen fuel cells or another form of environmentally friendly fuel will fuel the electric propellers. This means the Aeroscraft will be both efficient and quiet.
 Image courtesy Worldwide Aeros Corp. |
On the Aeroscraft, the four canards and two empennages will keep it stable and allow the pilot to make minor adjustments to keep it flying level. Outside conditions, such as wind and air pressure, will be measured along with weight distribution inside the craft. If all the passengers suddenly run to the port side of the craft to see something, the control system can compensate for that. Air from outside will be sucked into holding tanks, where it will be compressed and used as ballast.
All pilot control and avionics systems will use Fly-by-Light (FBL) technology. The pilot's commands are fed into a flight control processor and sent to the surface actuators via electrical signals transmitted along fiber optic cables. In Fly-by-Wire (FBW) Systems, wires must be shielded from electromagnetic frequency (EMF) interference, which results in additional weight, cost and maintenance. FBL is immune to EMF interference, such as lightning strikes. The FBL, flight control processor and flight control devices make up the Onboard Data Exchange Managing System (ODEMS). This system means that the flight is mostly automated, with the two-person crew monitoring the flight conditions to ensure safety.
The Aeroscraft does not require an extensive ground crew for either takeoff or landing. Its Air Cushion Take-off/Landing System (ACTLS), located on the belly of the aircraft, creates a vacuum to anchor it upon landing. The ACTLS reverses upon takeoff.
Next, we'll look at proposed uses for the Aeroscraft.
- Dimensions (feet): 165 high x 244 wide x 647 long (in meters, 50 x 74 x 197)
- Range: 6,000 miles (9,656 km)
- Cruising Speed: 174 mph (78 m/s)
- Altitude Range: 0 to 8,000 ft (0 to 2438 m)
- Payload: Up to 250 passengers or 400 tons (362,874 kg) of cargo
Proposed Uses
Designers envision the Aeroscraft operating like a luxury cruise ship that sails through the air instead of the ocean. Up to 250 passengers will travel in comfort and style, with sleeping quarters, restaurants, a casino and other amenities. The Aeroscraft will be able to cruise past scenic landmarks to give passengers a stunning view, even if the landmark is in the middle of a jungle. The passenger version is the Aeros-ML, which would have a smaller configuration, with room for about 120 passengers or 20 tons of cargo.
 Image courtesy Worldwide Aeros Corp. |
The Aeroscraft also has potential as a cargo ship. There are two versions for freight -- the Aeros-D4 and the Aeros-D8. Currently, time-sensitive cargo is usually shipped by land because shipping by airplane is cost-prohibitive and has weight limitations. But the Aeroscraft's cargo hold of two acres can accommodate 400 to 500 tons of cargo, and it can handle huge items that can't be disassembled, like oil rigs or huge pieces of factory machinery. It will be able to move them without disrupting traffic, and much more quickly than trucks can. Aeroscraft's designers think it will be able to do so at a competitive cost. It may even be able to carry "an entire store's worth of merchandise directly to a Wal-Mart" [ref].
 Image courtesy Worldwide Aeros Corp. |
That kind of cargo capacity interests the military as well. It could carry an entire company (100 to 200 troops), all of their equipment, all their support troops, fuel, rations, water and everything else the company would need to set up and go to work fighting a war, all in an aircraft that could drop them anywhere. Such a craft could revolutionize military logistics.
Worldswide Aeros was one of two companies to receive a $3 million preliminary design contract to design a vehicle for DARPA's Walrus program. DARPA (Defense Advanced Research Projects Agency) is the research and development arm of the U.S. Department of Defense. The Walrus program was created to develop a large heavier-than-air aircraft to deploy both military personnel and equipment. However, the project is currently without government funding, and DARPA's budget request for the 2007 fiscal year called to terminate Walrus at the end of this developmental phase "in keeping with congressional intent" [ref]. The company is still moving forward with its prototype development and plans to have it ready within 18 months.
Recently, the U.S. Air Force awarded Aeroscraft with a Phase I Small Business Innovative Research Program (SBIR) Award. This award "encourages small businesses to explore their technological potential and provides the incentive to profit from its commercialization" [ref]. Aeroscraft will use the award to develop high-altitude, near-space aircraft that can perform many of the same duties as Earth-orbiting spacecraft or satellites at a fraction of the cost.
The Aeroscraft Company also thinks their airship will be perfect for commuter flights. According to their Web site:
For short-haul markets, The Short Take-Off and Landing ("STOL") capability of Aeroscraft, its relatively low noise, and efficient fuel consumption (due to lower power levels) give the Aeroscraft power advantages. Aeroscraft will be comfortably competitive in short-haul markets, which have to date been largely uneconomical for traditional airliners. The airlines have largely abandoned service routes between 20 and 300 miles, but Aeroscraft could operate profitably in these markets, restore service between city centers and even minor airports, and work as a feeder to international airports and hubs.
Some other suggested uses:
- Agriculture and Environmental - An Aeroscraft could carry a huge amount of water to dump on a fire in a remote location. It could also deliver fertilizer and assist in identifying sources of pollution.
- Disaster relief - In the wake of a natural disaster, the lack of infrastructure can make it very difficult to bring in aid supplies in large quantities. The Aeroscraft could haul medical supplies, drinking water and food directly to the affected areas.
Worldwide Aeros plans to have a prototype Aeroscraft ready for testing by 2010. It's too early in the development stage to know how much it will cost to manufacture an Aeroscraft. However, the company claims that they will cost 30 percent less in capital costs and 50 percent less in maintenance costs than conventional aircraft [ref]. Two companies have already signed agreements to receive the first Aeroscrafts when it is ready for commercial production.
For lots more information on the Aeroscraft and related topics, check out the links on the next page.
 Image courtesy Worldwide Aeros Corp. The Aerostat, a tethered balloon system made by Worldwide Aeros |
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