NASA and AeroVironment, flew a prototype unmanned Helios aircraft running on sunlight during the day and fuel cells at night (photos).
During a test last week at the U.S. Navy’s Pacific Missile Range Facility on Kauai, Helios spent 14 hours aloft and glided to altitudes as high as 52,000 feet. The purpose of the flight was to demonstrate the ability of hydrogen-powered fuel-cells to power the 246-foot-long, solar-powered flying wing at night.
The aircraft, which is driven by 14 propellers turned by small 2-horsepower electric motors, ascended to 50,000 feet, ran on the fuel-cells for several hours and landed back at the missile range facility about 4 a.m. Sunday.
The 743-pound fuel-cell system combines oxygen from the atmosphere with hydrogen gas contained in two pressurized tanks mounted on Helios’ outboard wing sections. The hydrogen and oxygen are fed to a series of proton-exchange membrane fuel-cell “stacks” mounted in the central landing gear pod. The experimental fuel cell is expected to generate 15 kilowatts to power the aircraft’s 10 electric motors that turn propellers.
Researchers are also experimenting with liquid hydrogen. That would allow an aircraft to stay up for as long as two weeks and useful in areas like Alaska, where sunlight conditions are not suited for solar flight.
In 2001, the aircraft set an altitude record for a non-rocket powered aircraft of 96,500 feet .
NASA hopes to develop an unmanned aircraft that can stay aloft indefinitely and serve as a platform for photographic, sensing and communications platform. It would be cheaper to operate and easier to get into place than a satellite.
If it works, it will “be the equivalent of an 11-mile-high tower in the sky,” said Bob Curtin of AeroVironment Design Development Center during development of the project in 2001.
In the past three years, the military has been testing a new generation of mini-UAVs as part of their Dragon Eye program.
Although they resemble the model airplanes, they’re not toys. Unmanned Aerial Vehicles generally fly a preprogrammed route. Some carry microphones to listen for enemy vehicles, sniffers that can detect a chemical agent, and cameras. The idea is to give individual soldiers a better idea of what might be over the next hill.
AeroVironment, is competing against BAI Aerosystems, for the Dragon Eye contract. Lockheed Martin’s advanced technology unit is also at work on a small aircraft, the Sentry Owl, under an Air Force program.
The Defense Department is expected to spend about $1.5 billion for all UAVs for 2004. That includes larger craft like General Atomic’s Global Hawk, Northrop Grumman’s Predator, United Industrial’s Shadow, Boeing’s Unmanned Combat Air Vehicle, and AeroVironment’s Pointer, a glider-like airplane with an 8-foot, 4-inch wingspan which has been in service with the Army and Marines since 1989.
Daily Wireless has more on Unmanned Aerial Vehicles, War Flying and Flying Hot-Spots.
Next year: pinging your bank card RF-ID from 80,000 feet.
