Flexible blimps are bending the rules on UAV design.
- By Michael Klesius
- AirSpaceMag.com, December 18, 2009
(Page 2 of 2)
While research is moving ahead on how to get propeller-driven, airplane-type unmanned aerial vehicles (UAVs) to stay aloft for weeks, months, or even years—mainly with light, durable solar cells that charge batteries by day to keep the propellers turning at night—Sanswire-TAO claims they’re ready to fill a need now for more persistent UAV loitering where it’s needed: mainly in the military, but also for homeland security, border patrol, environmental study, commercial telecommunications, and maritime needs.
“We said, ‘Duration, duration, duration,’ measured in weeks. That’s what our soldiers need now,” says Erdberg. Sanswire-TAO conducted their latest demonstration of their airship on December 17 and 18 in Stuttgart. “We’ve built about 30 prototypes and have flown them thousands of times,” he says.
He claims that the cost of a Predator-class UAV is many times the cost of an airship of this kind. An STS-111 would run about $3 million to purchase, but only about $50 an hour to operate. “You crash a Predator, and that’s a tremendous cost, somewhere between $12 million and $18 million a pop,” says Erdberg. “Predators run around $2,000 an hour [to operate], and sometimes much more.”
The Stratellite, the company’s high-altitude vehicle, would find what Erdberg calls a “sweet spot” around 60,000 feet where it would experience the least amount of average wind. “Below and above that layer it’s very windy,” he says. “The idea,” he continues, “is to mix a balloon with an airship. Without fuel, it just becomes a balloon.”
Erdberg says that solar cell technology isn’t as far along as it needs to be. One of many problems for solar cells operating at very high altitudes is overheating from the sun’s powerful radiation. “We do believe that solar technology is the future,” says Erdberg. He claims that the company is doing research in that area. “But our gas technology is ready today.” In the second quarter of 2010, the company plans a public unveiling of their airships for two days at the Orlando Sanford International Airport.
“This is outside the box,” Erdberg says. “You’re taught something in school every day, but then this is something very different.”