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Famous Speedboats of the World
- Boats That Can Almost Fly
Published in Famous Speedboats
of the World 1959, Written by: D Phillips-Birt
You may be wondering what can happen next to make yet faster
boats and higher world's speed records. This is a difficult
question to answer, for you have no doubt already realise
that the record breakers of the last ten years or so are only
just boats. They are boats on the verge of flyingflying
boats without wings, which cannot take to the air yet do no
more than merely touch the water that carries them. But so
great is their speed that though only a few square inches
of the boat may at any moment be' in contact with the water,
each touch of it is like the blow of a giants' hammer threatening
to break open the skin of the hull. And all the while is the
ever-present danger that forces of the air rushing past the
hull may hurl it over on its side or back to destruction.
Perhaps there is a limit not far away beyond where we are
now when further speed becomes impossible. We have come a
long way in the half century that separates Dixie cutting
through the water at about 40 miles an hour and Bluebird skimming
over it at nearly 250 miles an hour. Speeds have been increased
by five times, a total of 200 miles an hour, and a little
arithmetic will show that this averages an increase in speed
of five miles an hour for every year since the early part
of the century. A little more arithmetic will show that if
the same rate of progress were to continue boats would be
able to travel at between 400-500 miles an hour by the year
A.D. 2000. Will this happen? I do not think so. Before long
higher speeds will become impossible. This need not surprise
you. You may remember that in the first chapter it was shown
that the speeds of ships during the many centuries when the
only way of propelling them was by means of wind in sails
or the muscles of men using oars, speeds increased very little.
A limit of development had been reached. The same thing may
happen again. The laws of nature may forbid yet faster speedboats.
You need not be disappointed either. We are speaking here
only of maximum speeds, the speeds that make the world's records.
Though the jet-propelled hydroplanes of this kind may now
be able to do more than 250 miles an hour, the fastest type
of boat capable of going to sea in even a modest way, and
making short passages along a coastline or across the Channel,
cannot manage more than about 50 knots or 572 miles an hour.
You see what a huge gap there is between the world's record
and the fastest type of boat that is capable of any useful
work, carrying passengers or crossing an ordinary sort of
seaway. This is a gap that waits to have a bridge thrown across
it. Already today some progress is being made in the work.
In its way it is almost as exciting as record breaking.
We have seen that the record-breaking boats of today are
of no use for anything but running over measured miles or
kilometres on the most placid lake water, and they do even
this at considerable risk to the pilot. It does not mean that
the boats are useless; they may be able to provide valuable
lessons to guide the design of slower but more practical vessels.
We have also studied the types of fast boat used in the Mosquito
fleets during two world wars-boats owing a debt to what was
learned from the record breakers of their day. These small,
fast warships, having to carry their load of guns, torpedoes,
and ammunition and to remain at sea in rough weather were
unable to achieve much more than 45 knots. Yet we should remember
that this is about as fast as any seagoing ship of any size
has ever moved. A naval destroyer is not so fast, and the
express Atlantic liners rarely exceed 31 knots.
The problem of designing really fast boats that are at the
same time moderately seaworthy and able to carry a useful
load is a difficult one. Not only must they be able to drive
their way or skim over the dense and "sticky" substance
that water is, but they must be able to face waves. For the
surface of the sea, even in the calmest weather, is rarely
quite flat, and in only a light wind waves are raised capable
of endangering the record-breaking kind of boat. It is the
fact that the sea is always more or less rough, and sometimes
very rough indeed, that makes speed over it so difficult!
Though you may be able to produce a boat able to reach 100
knots or so it will be forced down in speed to a mere ten
knots and less as soon as the wind whips the surface of the
water into even small waves. Against the enormous storm waves
of the ocean, of course, few ships can move at even this speed,
and often they are forced to heave-to, that is, to stop going
ahead at all.
The aeroplane is able to avoid the turmoil of the ocean surface
by soaring above it; the submarine by diving beneath into
the dark regions of water which are perpetually still however
tumultuous the storm waves above. The ship alone is tied to
the tumult and compelled to fight it.
During recent years a brilliant though not new idea has been
applied to fast boats. This consists of nothing less than
lifting them out of the water on what we may think of as water
wings fixed to stilts projecting below the surface. By this
means the hull itself is in the air, above the rough surface
of the sea, free from its resistance and the blows of the
waves.
You will wonder how this is done. You know that an aeroplane
is carried on its wings. Wings are long, slender, more or
less flat objects, and when these pass through the air at
a suitable angle they are able to generate what is aptly called
"lift", which is a force acting upwards and able
to support the aircraft. Wings are able to work in water as
well as air. They are able to do so more effectively, in fact,
for water is the thicker or more dense substance.
Suppose therefore we arrange for a boat to be fitted with
wings on legs so arranged that they may project down into
the water under the hull. Then, when the boat gathers speed
the wings are able to lift the boat; when it is going fast
enough they are able to lift the hull altogether out of the
water. Then you have nothing in the water but the wings themselves,
supporting the hull clear of the sea. Such wings are called
"hydrofoils" just as the wings of an aeroplane may
be called "aerofoils".
It is easy to see that the idea of hydrofoil craft is a most
promising one, and during the last few years big developments
have been made with them. Like many other good ideas this
one was born years before it produced any striking results.
At the time when the early skimming boat Maple Leaf IV was
becoming famous, two Americans fitted hydrofoils on a small
rowing dinghy. The foils were no more than narrow wings fixed
across the hull a few feet beneath the bottom. When the dinghy
was towed astern of a motor boat it was lifted on the hydrofoils
clear above the surface of the water. At a speed of only six
knots-unspectacular even for those days-the hull of the dinghy
was raised by the hydrofoils altogether out of the sea.
Other experiments were made, especially with models, for
here as elsewhere models proved of the greatest value in discovering
the value of new ideas. In 1919 trials were made with hydrofoils
arranged like a ladder under the hull of a boat, and this
is of particular interest because it is one of the systems
in use today. You will be able to understand the arrangement
from the illustrations. But still at this time, though the
idea appeared interesting, there seemed no practical application
for it, and few important developments have occurred. However,
in 1914, a hydrofoil craft known as HD/4 reached a speed of
a little more than 70 m.p.h. on the Bras d'Or lake in Nova
Scotia, Canada. She was thus the fastest boat in the world
at that time, proving capable of higher speeds than the skimming
boats of her day; but because nobody could regard a craft
that was lifted above the sea by wings on stilts as a true
boat the achievement did not lead to any sustained interest
or further progress. There was still so much to be done in
producing faster boats of a more ordinary kind.
But hydrofoil vessels were not wholly forgotten, though much
more attention was devoted to the skimming speedboats that
we have been dealing with earlier. The Germans were especially
interested in the hydrofoil idea, and this culminated during
the Second World War when a number of hydrofoil craft were
designed, built and tested under the authority of the government.
One such boat was 46 ft. long and was able to carry a pair
of torpedoes at a speed of 55 knots. Here obviously was a
great achievement, but the Germans found many snags in their
efforts to produce hydrofoil craft capable of taking an effective
part in the operations of war, and in spite of their efforts
none was ever used for fighting.
After the war the British Admiralty were able to examine
what the Germans had achieved. We now reach the point in our
story when Sir Malcolm Campbell was trying to raise his speed
record of 141.7 m.p.h., when naval torpedo and fast gunboats
were capable of 50 knots; when, in fact, speeds over the water
were so high that it appeared difficult to make them any higher,
especially if a craft able to operate in a rough sea was needed.
The hydrofoil principle now gained a new significance. Here
perhaps was the way of achieving not world record breaking
speeds, but at least speeds far higher than any previously
within the range of possibility so long as boats had to plough
through the surface of breaking waves.
The British and Americans both settled to work. A British
inventor, Christopher Hook, patented a type of hydrofoil craft;
the American Navy instigated a programme of research. A hydrofoil
craft named White Hawk owned by two English people, Mr. and
Mrs. Hanning-Lee, reached a speed of 125 m.p.h. on Lake Windermere,
where Sir Henry Segrave and one of his mechanics had been
killed going at almost the same speed in Miss England II,
more than twenty years earlier. The important day of the hydrofoil
craft-though such had been known and used for nearly half
a century-was opening.
Now the firm of Saunders-Roe, which built some of the earliest
of the speedboats that we have discussed, and which have continued
throughout our story of speed at sea to build important craft,
was commissioned by the Canadian Government to design and
build a hydrofoil vessel 60 ft. in length. She had her sets
of hydrofoils forward and aft arranged on the ladder system,
and she was named Bras D'or after the lake where thirty-two
years earlier the HD/4 had achieved a speed of 70 m.p.h.
We can expect that in the future more and more use will be
made of hydrofoil craft, and they may become quite a common
sight round the coast and for short sea passages where speed
is important. This does not mean that large ocean-going ships
like liners or aircraft carriers will be lifted on hydrofoils.
For reasons that we need not discuss, there is a limit to
the size that hydrofoil craft may be. Exactly what this limit
is nobody can yet be sure, but it would be far below that
of the liner or bulk cargo carrier. But they will come to
be used as ferries and for similar fast passenger purposes,
perhaps across the Channel and in the North Sea. For the first
time in the history of seafaring, vessels as fast as certain
types of speedboats will be able to cross stormy stretches
of the sea without loss in speed, carried in the air, above
the disturbance, on their hydrofoils. This, you will agree,
is an exciting development to expect.
Meanwhile, speedboats of the skimming type continue to be
used for many purposes. These are fairly good seagoing vessels,
but not nearly so fast as the world's record breakers we have
been describing. But they are capable of speeds of from 40
to 5o knots, of remaining at sea in rough weather, and performing
many vital services. Such craft may be used for ambulance
purposes, for fire fighting, and for carrying passengers.
Working craft of this kind are the development of the last
fifty or so years, during which men have been striving towards
ever higher speeds over the water.

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