Six-year old Falcon Heene was found safe at his home, following nationwide fears that he was inside a bizarre, homemade balloon that slowly descended in a Colorado field Thursday.

The aircraft was as an "experimental" ship built by the missing boy’s father, Richard Heene. But details on the 20x5 foot mylar homebuilt helium balloon are scarce, though the weather balloons used by storm chasers are fairly common, and have been for decades.

"We were working on an experimental craft," he told reporters. "I call it the 3D LAV, a low-altitude vehicle for people to pull out of their garage and hover above traffic for about 50 to 100 feet. It's still in the very early stages."

The Heene family was on the ABC reality TV show “wife swap.” The show’s Web site briefly describes the family’s hobby: "When the Heene family aren't chasing storms, they devote their time to scientific experiments that include looking for extraterrestrials and building a research-gathering flying saucer to send into the eye of the storm."

ABC News spoke with Dick Knapinski of the Experimental Aircraft Association, based in Oshkosh, Wis. He noted that "if you were to build something like this, it would need to be registered with the FAA," pointing out that "it would have to be inspected, and it would have to have markings showing its identity."

By Heene's own admission, the device was still in the early stages, not yet ready for flight. Heene has a history of building his own devices, including a magnetometer-carrying rocket and a specialized racing bike he rode under storms. He may have intended this experimental craft for similar studies of magnetic fields in storms.

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Nearly all stations in the United States that operate weather balloons use hydrogen gas to inflate them, as was the case with Richard Heene’s craft. The basic idea isn't to send weather balloons directly into storms but to have them probe the winds hundreds of miles around them: winds that steer a hurricane and determine its course. As such, the balloons are designed to fly unmanned at the rapid speeds created by storms.

Currently, researchers get information about those steering currents in several ways. Over land, National Weather Service offices launch weather balloons twice a day. Unlike the hurricane balloons, which will float for days, the weather service balloons send back data for between an hour and a half and two hours before they pop and fall back to land.

Ocean going balloons are somewhat more advanced. Sometimes equipped with a GPS units, they are designed to stay aloft from two to seven or more days, sending back their altitude and position every 15 minutes, before losing their helium and crashing into the ocean.

Click here for more on this story from MyFOXColorado.com.

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