Such was the assessment of Jonathan Klinger, vice president of press relations for Hagerty Insurance, a specialist company that covers collector cars. The machine that inspires such fulsome praise? The 1961-68 Amphicar.

Flying cars are nowhere in our skies and James Bond’s Lotus Esprit submarine remains but a fictitious point of fascination, but for much of the ‘60s it was possible to buy a mass-produced, turn-key car that also functioned as a boat.

Related: ‘Where is my flying car?’

Though not superlative, the Amphicar was serviceable in its dual roles, and its manufacturer was owned by BMW’s parent, the Quandt Group, not some fly-by-night backyard operator. This was a real product, not a glued-together kit car.

The Amphicar is notable not just for just presenting a novel way to chase ducks in a pond. Hagerty Insurance began its corporate life covering boats, and its Amphicar customers get two policies: a car policy and a boat policy. “Cars aren’t covered in the water,” Klinger says. “Just as the vehicle has two registrations, one as a car and one as a boat, it has two policy numbers.”

Not an inexpensive proposition, then, this Amphicar ownership.

Developed by German designer Hans Trippel – more fondly remembered for his work on Mercedes-Benz 300SL’s “gullwing” doors – the Amphicar looks like many other German compact sedans penned during the ’50s. Think DKW crossed with Wartburg and Trabant – on tip-toes.

The Amphicar’s smoothed underside rises high above the protruding wheels to avoid scraping as it slides into the water from boat landings. The pointed bottom side of the prow is somewhat discrete beneath the Amphicar’s fairly conventional nose, helping hide its secret identity, like Clark Kent’s suit covering a blazing “S”.

But like Superman’s cape peeking out from Kent’s shirttail, the Amphicar’s double life is laid bare at the stern, where twin propellers betray the car’s other powers.

US President Lyndon Johnson, an Amphicar owner, was reportedly fond of shouting, “The brakes don’t work, we’re going in,” while piloting his Lagoon Blue Amphicar into a pond on his ranch. The US National Park Service, which administers a park in Johnson’s native Texas that is named after the 36th US president, notes that he used this experience to test the mettle of prospective staffers.

A hole in the bottom of a car is an annoyance; a hole in the bottom of a boat is a disaster.

With Amphicar survivors ranging between 48 and 55 years old, some testing of their metal, as it were, is in order before splashing down. If drivers are not diligent with their bilge pumping, water will collect in the bottom of the hull, rusting holes right through the car. A hole in the bottom of a car is an annoyance; a hole in the bottom of a boat is a disaster.

“You want a rust-free vehicle, not only from a structural point of view, but also so that it is waterproof,” Klinger counsels. “If it was ever used in salt water, and some of them were, that can cause some serious issues.” Even among cars sound enough for a quick spin in the water, “you might not want to tie them up at the dock and walk away,” he says.

According to its brochure materials, the Amphicar’s engine was a 38-horsepower 1,147cc four-cylinder borrowed from the Triumph Herald saloon. The engine mounts in the rear, driving the rear wheels through a four-speed manual transmission. Through a transfer case like those found on four-wheel-drive vehicles of a certain vintage, the engine spins the dual propellers.

Alas, no volume of froth from those props will get the Amphicar up on plane, so it can merely chug like an aquatic tractor through the water; no pulling water-skiers behind this rig (at least not very quickly).

Because its wheels hang down in the murk, the Amphicar’s official top aquatic speed is limited to 7.5mph. The front wheels also serve as rudders, steering the Amphicar through the water as they do on terra firma.

The doors have secondary rubber seals to keep water out while under sail, and the folding convertible top and roll-up side windows provided all-weather utility on water and land. With only 55 centimeters of clearance between water and window line, however, use in anything but light seas would have the car awash, so the Amphicar is strictly a fair-weather toy.

A radio was optional, as was commonly the case among cars of this vintage. Paddles, life jackets and fire extinguisher were also optional – and less common, then as now.

The Amphicar’s mediocrity as a boat and a car limited sales to slightly fewer than 4,000 units during the machine’s production run. Interest among collectors continues to be steady, if not spectacular. “They are rare enough that they are going to continually increase in value,” says Klinger of Amphicars. “For someone who really wants to have a diversified car collection, it is a good addition.”

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