The Ride Aquatic

The 2-seat Hydra Spyder, built by Cool Amphibious Manufacturers International in Ridgeland, S.C, starts at $175,000 and is powered by a Chevrolet Corvette LS2 V8 engine. Drive it into the water, flip a switch, and the wheels retract into the vehicle's body, the doors deploy to cover the bottom of the wheel wells (much like when an airplane retracts its landing gear), and a marine gear engages a jet-drive engine like those used on personal watercraft. Now you are ready to set sail. Only five have been built so far, all bought by filthy rich folks who keep them on their multimillion-dollar yachts for shore leave.

View Pictures:  Aquatic Rides

If its wheels stayed in place, the Hydra Spyder would be no faster than its larger stablemate, the bus-sized Hydra Terra. "It doesn't matter if you put 500 horsepower on it, it's not going to go any faster, because it's limited by drag," says John Giljam, who founded Cool Amphibious Manufacturers in 1999 with his wife, Julie. The bulk of Giljam's business comes from the Terra, which is used commercially, mostly by tour operators in a 49-seat configuration. He's working on another high-speed amphibious vehicle for military use, which would take him full circle: Giljam first got into amphibious vehicles by converting an old LARC military cargo vehicle to run tours off Hilton Head Island.

Dave March, founder of WaterCar Inc., in Fountain Valley, Calif., got into building amphibious vehicles after restoring an old German Amphicar from the 1960s. Seeking something faster, he toyed with a small 2-seater that looked like a late-1990s Chevy Camaro. It had a Subaru WRX engine, retractable wheels and water-jet propulsion. Unfortunately, the vehicle's flat bottom didn't allow it to cut through the water smoothly. The Python is March's solution — a larger vehicle with V-shaped hull. Like the Hydra Spyder, it's powered by a Chevy LS V8. It's capable of 60 mph on the water, and zero to 60 mph in 4.5 seconds on land. Available as a kit car (sans engine and transfer case), the Python costs about $200,000.

In addition to the Python, WaterCar also offers a less expensive and slower model — capable of 8 mph on water — called the Gator, which looks like a Jeep but uses a Volkswagen Beetle chassis and engine. It's also available as a kit car. This allows WaterCar to circumvent federal crash tests and safety regulations, which would be prohibitively expensive for the start-up to comply with. The Gator kit costs $29,500 without the chassis and engine.

Bing: WaterCar

Gibbs Technologies is unique in this group in that it seeks to mass-produce an amphibious car that does 35 mph on water, is relatively affordable and complies with boat and road regulations in North American and Europe. The Aquada is a 3-seat, center-console vehicle with retractable wheels and a V-shaped hull for better stability at high speeds on the water. In 2004 Sir Richard Branson, founder of the Virgin empire, set an amphibious vehicle record by driving the Aquada across the English Channel in just over 100 minutes. The company had set a target price in the U.S. of $85,000 for this speedster and a release date of 2009, but a snag with emissions regulations has shelved production plans indefinitely.

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With the Aquada project on hold, Gibbs is focusing on a smaller model called the Quadski. This all-terrain vehicle can convert into a personal watercraft in less than five seconds. The goal is for it to be able to reach 45 mph on land and water. The first production run of about 2,500 units is expected to go on sale next summer. Pricing and further technical details have not been announced. Another model set to go on sale next year is based on an SUV-like prototype called the Humdinga. It will be larger than the Aquada and targeted at law enforcement and emergency-response agencies.

Bing: Gibbs Technologies

It's hard not to grin when you see the Rinspeed Splash drive into the water, deploy its hydrofoils, lower a propeller and start to glide a few feet above the waves. Piloting the Splash, probably the only hydrofoil car in existence, on the water can be tricky, however. "It's speed versus angle of the wings versus waves," says Frank Rinderknecht, Rinspeed founder and chief executive. The "wings" are attached to the vertical part of the front hydrofoils underwater. Much like the way water-skiers must hold their skis at a steep angle to get out of the water, the wings on the Splash must be positioned at a steep angle when the vehicle takes off, so that it can rise out of the water.

This Rinspeed creation is as equally intriguing as the Splash, but perhaps even more whimsical. The primary reason Rinderknecht cites for building the sQuba was to prove that a car like the white Lotus Esprit that James Bond drove into the Mediterranean Sea in the 1977 film "The Spy Who Loved Me" could actually be modified to do so. Rinspeed started with a Lotus Elise, removed its combustion engine and transmission, and replaced them with five electric motors: one to drive the wheels, two to power a couple of propellers at the rear, and two more to power nozzles on either side of the vehicle, just behind the front wheels.

Bing: Rinspeed

Matthew de Paula wanted to be an automotive journalist ever since reading his first car magazine in grade school. After a brief stint writing about finance, he helped launch ForbesAutos.com and became the site's editor in 2006. Matthew now freelances for various outlets.

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