British Airships in the First War
[Illustration: Airship over water]
Germany entered the first World War with high expectations as to one,
perhaps two of its new weapons of war. Its submarines might offset
Britain’s superiority at sea, and certainly the Zeppelins, which had
proved themselves in four years of commercial flying, would be able to
cross the English Channel and carry the war to the island which had seen
no invasion since William the Conqueror.
No nation except Germany had Zeppelins. And as the German people began
to feel the pinch of the blockade, cutting their life line of food and
supplies, they brought increasing public pressure on High Command to use
these weapons to punish England.
Later commentators have speculated as to whether, if Germany had held
its fire, waited till it could assemble an overpowering force of
Zeppelins and submarines and stage a joint attack, it might not have
been able to force a quick decision.
But the Zeppelins were sent over a few at a time, as fast as they could
be built, and England was given time to devise defenses. These were
chiefly higher altitude airplanes, farther ranging anti-aircraft guns,
sky piercing searchlights, which combined to force the invaders to fly
continuously higher as the war wore on, as high as 25,000 feet at times,
with corresponding sacrifice of bombing accuracy. And when machine guns,
synchronized with the propellers, were mounted in airplane cockpits, and
began to spit inflammable bullets into the hydrogen filled bags and send
them down in flames, the duel took on more even terms.
Less spectacularly the Zeppelins were used on a wide scale as
reconnaissance and scouting craft, which flying fast and far were given
credit on more than one occasion for saving German Naval squadrons from
being cut off by superior Allied forces, were acknowledged even by the
British to have played an important part in the Battle of Jutland.
It is a little hard to realize today that whatever air battles were
waged over water in the last war were conducted chiefly by
lighter-than-air craft. Planes staged spectacular battles along the
Allied lines in France, but lack of range and carrying capacity forced
them to leave sea battles to the airship. As a measure of that
situation, the great hangars at Friedrichshafen, spawning ground of the
Zeppelins, one of the outstanding targets in all Europe if England were
to draw the dirigible’s fangs, lay hardly more than a hundred miles from
the French borders, but even that distance was too great for effective
attack.
While these greater events were taking place, British airships, smaller
in size, less spectacular, were playing no small part in repelling
Germany’s other threat, the submarine.
Blimps Used to Search for U-Boats
Navy opinion around the world was skeptical at the beginning of the War
as to whether submarines would ever be practical. There were mechanical
troubles, accidents, usually costly. Even Germany, prior to 1914, used
to send an escort of warships along to convoy its subs to their
station—then send out for them afterward to bring them home again.
But the war was only a few weeks old when the captain of the U-9,
cruising down the Dutch coast, discovered that his gyro compass was off,
and when he got his bearings saw that he was 50 miles off course. He
wasted no breath, however, on many-syllabled German swear words, for off
on his southern horizon were the masts of three British ships. He dived,
came up alongside, and in 30 minutes, single handed, with well directed
torpedoes, had sunk in turn HMS Aboukir, Hogue and Cressy.
The morning of September 22, 1914, marked the beginning of a new era in
Naval warfare. The warring nations grew furiously busy building their
own U-boats and devising defenses against the enemy’s. Among these
defenses was the non-rigid airship.
These two vehicles, so widely different, have much in common. If we may
be technical for a minute we may say that the airship and the submarine
are both buoyant bodies, completely immersed and floating in a
medium—air and water respectively—of changing pressures, that each uses
dual sets of steering gear and rudders to control direction and
altitude. And further, that the airship in 1941 faces the same division
of opinion as the submarine faced in 1914, as to whether, particularly
with rigid airships, it will ever be widely used and accepted.
In any event in 1914 there was an urgent and immediate job to be done.
Indicator nets and high explosive mines might give some protection to
harbors, might be stretched across steamship lanes and planted around
the hiding places of the submarines, if those could be discovered. But
troop ships and munition ships and food ships must be dispatched without
interruption across the tricky waters of the English Channel to France,
and for this purpose convoy escorts were devised, with camouflaged
warships zigzagging alongside, while high aloft in lookout stations men
with binoculars strained their eyes, searching the waters, ahead,
astern, alongside, their search lingering long over every bit of
floating wreckage—and there was a lot of it—to make sure it was not a
periscope.
These lookouts aboard ship quickly had a new ally in the air. As the
submarine menace grew, binoculars began to flash too from the fuselages
of bobbing blimps overhead. At a few hundred or perhaps a thousand feet
elevation they could see deep below the surface, and quickly learned to
recognize at considerable distance the tell-tale trail of bubbles or
feathered waters or smear of oil which denoted the enemy’s presence,
might even pick out the shadowy form of the submerged craft itself.
The value of the airship in convoy was that it could fly slowly, could
throttle down its motors and march in step with its charges, cruise
ahead, alongside, behind. The very speed of its sister craft, the
airplane, handicapped its use in this field.
This characteristic of the blimp was even more useful in hunting U-boat
nests. The blimp could head into the wind, with its motors barely
turning over, hover for hours at zero speed over suspect areas. It could
fly at low altitudes, follow even slender clues. Seagulls following a
periscope sometimes gave highly useful information. An orange crate
moving against the tide attracted the attention of one alert pilot, for
the crate concealed a periscope, and the blimp dropped
bombs—successfully.
When a blimp discovered a submarine, it would give chase. With its 50
knots of reserve speed it was faster than any warship, much faster than
the poky wartime submarine, which could do only 10 or 12 knots on the
surface, much less than half that when submerged. If it was lucky the
airship might drop a bomb alongside before the sub got away.
And run for cover the submarine always did. It wanted no argument with a
ship which could see it under water, could out-run it, and might plunk a
bomb alongside before its presence was even suspected.
Airships did get their subs during the war. The records, always
incomplete in the case of submarines, whose casualties were invisible,
show that British blimps sighted 49 U-boats, led to the destruction of
27. But their greater usefulness lay in the fact that their mere
presence sent the underseas craft scuttling for submerged safety.
Between June, 1917, and the end of the war British blimps flew 1,500,000
miles, nearly as many as the Zeppelins. A French Commission made an
exhaustive study of dirigible operations after the war, and the late
Rear Admiral W. A. Moffett quoted from its reports in summarizing
lighter-than-air lessons taken from the war, when he told the Naval
Affairs Committee of the House of Representatives that “as far as they
could learn, no steamer was ever molested by submarines when escorted by
a non-rigid airship.”
France and Italy had long coast lines, used the blimps extensively along
the Bay of Biscay, the Mediterranean and the Adriatic, but England found
still greater use for them because it was an island. So blimp scouts
played a singularly useful role from Land’s End to the Orkneys, stood
watch at the mouth of the Firth of Forth, the Solway, the Humber, and
the Thames.