Garage inventor builds amphibious vehicle that works
KETCHIKAN - Stan Hewitt might be the new king of garage inventors.
His amphibious vehicle - imagine a cross between a work skiff and a 1950s sci-fi movie Mars rover - looks cool and actually works.
Its tank-like rubber treads can carry the craft across land at speeds of up to 30 mph. And, in water, the treads flip up so the Volvo Penta SX outdrive can propel it just as fast on calm seas.
"This is not the regular, everyday rig you're going to see," Hewitt said recently, after testing the "Hewitt Amphib" prototype successfully in Tongass Narrows.
Its 17-foot aluminum hull gleams in Hewitt's garage, where he's spent much of the past 10 months building the vehicle. Except for the treads, engine/outdrive and some metal work, the amphib is entirely his creation, fabricated in his garage.
"I've got all the welding equipment and the presses to build this thing," he said.
But why would someone spend more than $70,000 and countless hours to build something like this? Duck hunting, for one.
Hewitt wanted an amphibious vehicle to access areas such as the mud flats near Wrangell that have prime duck habitat. He's also got property on Gravina Island that's basically inaccessible when the tide is down.
And, he simply enjoys making mechanical things.
Hewitt has a background that includes work as a mechanic in the Air Force and ownership of the Fireside Restaurant in Ketchikan. He's also a pilot and once operated an air-taxi service.
This is his second attempt at building an amphibious vehicle. His first was about 20 years ago, when he constructed a wheeled vehicle that went about 7 mph in the water.
He took it to Wrangell, but it wasn't fast enough to navigate well in river currents.
At a boat speed of 7 mph, "you're not going anywhere," he said. "You may be backing up."
Hewitt started thinking seriously about amphibious vehicles again when he traveled through Florida and Louisiana in 2002.
"Louisiana's got water everywhere," he said.
He began to research existing designs when he returned to Ketchikan.
"So many have been tried, and so many of them are failures," Hewitt said.
The main failure had been performance in water. The key is improving speed. And while speed was important, Hewitt also wanted a vehicle that could go just about anywhere on land.
"All I'm doing in the water is getting from this piece of land to that piece of land," he said. "This is 80 percent land vehicle and 20 percent boat."
A tracked vehicle solved the land side of the equation. An advantage tracks have over wheels is that they spread the vehicle's weight over a larger surface area, improving traction and reducing the vehicle's impact.
On Nov. 9, Hewitt powered it up for a spin in a calm Tongass Narrows.
"The thing went over 30 mph in the water, which was all I wanted it to do," Hewitt said. "I'd said if it would do 20, I'd be tickled to death, but it did 30. It felt like just as nice a boat as you were ever in."