Although it struggled to do more than four knots, with a bit of help from the tide we got to within five miles of France before the cooling fan broke and the motor set fire to its surroundings.

The big problem with cars that want to be boats, other than them catching fire and leaving you a sitting duck for a supertanker, is that the wheels get in the way and cause drag, with the result that the boat will never get on the plane (when the boat lifts and only the stern is in the water).

The Gibbs Aquada gets around this problem by having wheels that fold up and a speedboat-shaped hull. At about eight knots the front of the hull lifts itself up and you are on the plane. After that, it's 'plane' sailing and the Aquada will whoosh on to just over 30mph, which doesn't sound much but is 330i-type performance in the marine world.
In a tester's normal life, coming to a conclusion about a new car often requires a fair bit of pencil sucking. But judging the Aquada is extremely simple: it works, simple as that. And nothing that has come before it ever has: Amphicar, Dutton Mariner, nothing.

The Aquada's engine is from a V6 Freelander - itself a bit of a boat - and so is the transmission. The powertrain is fitted in the back of the vehicle with two drive flanges turning driveshafts to the rear wheels and the flange on the side of the automatic 'box connecting to Gibbs' own jet drive unit instead of a rear differential.

The really crafty area is the suspension. Springing and damping is by Citro