The 205,000-cu-ft hot-air blimp with a ribbed envelope flies for the first time.

A duct (blue-colored tube) that carries air from the fan into the bottom of the ship is visible on the right side of the photograph. The envelope is filled about halfway with cold air before the burners are fired up.

It might not be the perfect vehicle for everyone, but the personal hot-air blimp could be the next big thing for the pilot who wants to launch from the backyard. The blimp's designer, Dan Nachbar of Amherst, Mass., recently completed 10 hr of test flights.

Unlike other hot-air blimps, Nachbar's design has a rigid internal frame. And unlike helium blimps, it can be deflated and stored between flights without a hangar. The internal frame folds for storage. The blimp, which is 102-ft long and 70 ft in diameter, is capable of slow, low-level flight as well as turn-on-a-dime steering, according to Nachbar.

Nachbar plans to further develop his prototype and seek FAA approval to produce the airship commercially. A blimp would probably cost between $100,000 and $200,000, depending on configuration, he says. The ship could prove useful for tasks such as forest canopy research, wetlands survey/management, eco-tourism, aerial photography, and filmmaking.