Introduction to How the Aeroscraft Works
The Aeroscraft is a heavier-than-air vehicle currently in development for use in the near future -- a prototype should be finished by 2010. It will be able to haul massive amounts of cargo and transport hundreds of passengers in luxury with quiet, electric engines. It will also be able to take off and land without an airstrip. The Aeroscraft is sort of a hybrid -- it carries helium, like a blimp, but its shape provides lift, like an airplane. In this article, we'll see how the Aeroscraft flies and what it will be able to do.
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.
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.
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. TheFBL, 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.