length of the course. That all sounded fine to

me, and Hugh confirmed that, if we got it all

right, in theory I could hydroplane as far as

I liked until the fuel tank ran dry. Once I was

on the water, it would all depend on achieving

a perfect balance between the thrust from

the rear wheel and the drag generated by my

progress through the water.

Now things were starting to sound a bit familiar.

Hydroplaning is all to do with a build-up of

water pressure beneath the wheels. We’ve

seen in the previous chapters the effect that

air pressure can have, especially in generating

lift when it flows over a wing. As a fluid, water

behaves in much the same way that air does,

and marine engineers have understood this

for many years. A wing, or foil, works the same

way in water as it does in the air. As long ago as

the 1890s, boat designers were experimenting

with foils on their boats – hydrofoils – to lift the

hulls of the boats out of the water. An Italian

called Enrico Forlanini spent years developing

his hydrofoil boat, which he tested on Lake

Maggiore in 1906. The boat had two huge

propellers, both mounted above the water line

to operate in the air like aeroplane props, and

different levels of foils attached to the hull.

When the boat was at rest the hydrofoils lay

in the water, but as the props powered the boat

forward the hydrofoils lifted the hull clear

of the water. Forlanini’s boat was very quick,

achieving more than 42 mph (68 km/h),

making it one of the fastest boats in the world

at that time.

Inventor Alexander Graham Bell, the man

credited with inventing the telephone, met with

Forlanini when Bell was touring the world in

1911. Bell was hugely enthusiastic about the

hydrofoil concept and had sought out Forlanini

to take a look at his boat. Along with his chief

engineer, Casey Baldwin, Bell took a ride in

Top: Forlanini’s hydrofoil

rising clear of the water

on Lake Maggiore in

1910.

Middle: Guy Gibson and

his ‘Dambusters’ crew

boarding their Lancaster

bomber in 1943.

Bottom: The Mohne Dam

after being hit by 617

Squadron’s bouncing

bombs.

DISCOVERING THE WORLD OF HydroPLANING   143