A former rocket scientist's 56-foot-long houseboat — parked in his Florida backyard — has passers-by guessing whether they've gone into another dimension.

"Most people think it's a spaceship," Dennis Schaller told the South Florida Sun-Sentinel. "It was originally designed to be a hovercraft. Now it looks like it's going to end up as a houseboat. I won't live long enough to get enough money to make it a hovercraft — not unless I went back to work full time; and then I wouldn't have the time to work on it."

The creation — measuring 56 feet long, 20 feet wide and 17 feet tall — is a 20-year work in progress by Schaller, a former rocket engine mechanic in the Air Force before becoming an electrical engineer with North American Aviation, where he worked on several Apollo missions, including the Apollo 11 craft that landed on the moon.

Schaller, of Gifford, Fla., started building rockets as a kid and at age 15, took first place in the engineering division of the 1960 Georgia State Science Fair for his rocket, the Sun-Sentinel reports.

Schaller hopes to one day float his houseboat in Lake Okeechobee.

"I've got two more years to go if I keep working steady every day," Schaller told the Sun-Sentinel. "Of course, I've been saying 'two more years' for about 10 years now."

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