Airship Of Io
By Henry Gade
Io, Moon of Jupiter, is one of the most wildly
jumbled and mountainous worlds,
thus its aircraft are supreme.
Since this world, a satellite of giant Jupiter, is almost entirely coveral by a terrible jumble of mountain ranges, travel over its surface is a difficult thing, and its people, who live almost exclusively in underground cities built of pure crystal, have developed aerial travel to a high degree of perfection.
Their airehips would be the envy of Earth engineers, both as to construction design and motive power. A hundred thousand years of civilization have developed the airship of Io to almost one hundred per cent efficiency and perfection.
Io might be termed the arctic world of the solar system. It is a desolate waste of mountains and snow and giaciets, with desert areas between the mountains where nothing grows but a hardy cactus. The cities of Io are constructed of crystal, which occurs in natural formation on this world which abounds in silicon. Roofed over, with crystal roofs which collect and direct the meagre sunlight downward, their only practical access to the outside worid is by air, or by tunnel. A system of tunnels do exist, but are not extensively used. It is the airship that carries the burden of travd.
Airlocks in the domes of the cities admit the ships very conveniently, and great elevators take them down to city level.
On Earth, science is still experimenting with atomic power, using U-235 as fuel. On Io, this power has been used for centuries. Pitchblende deposits are available on Io in great quantity, having been exposed by the torture of its creation, which hurled its gigantic mountain ranges into being.
Therefore, U-235, available in quantities which make it the only practical fuel, has been developed until it has become the wonder-fuel of the solar system. The airship is the classic example of its highest development.
Strictly speaking, since Io has an atmosphere, the airship of Io is exactly that. It is an airplane, and has wings to support it. However, it more dosely resembles a rocket ship designed to traverse space than it does a plane.
Its body is a slim, streamlined, torpedo-like structure, peihape two hundred feet long. Its wings are very much like those of a bird, and rather short and stubby compared to the weight they are required to carry.
However, the super-power of atomic energy makes these smaller wings desirable, since power is cheap and available in great quantity and they make for greater maneuverability and greater stability and strength.
Rocket tubes, mounted in each wing, form the motive power, plus the directional power. Steering is by means of the motors almost entirely, simply by a delicate control of the jets. The plane itsdf operates mostly on the glider principle insofar as operation is concerned.
Actually, we might say that the airship of Io is a "steam" ship. It operates on water, which is broken down by the action of U-235 into its component atoms. Water is carried in four tanks, two located at the tail of the ship in streamlined containers, to add balance to the ship and in two more mounted in the forward part of the rocket tubes themselves. The water carried can drive the ship for many complete circuits of the planet, without being replenished. Mainly the quantity carried is to provide weight. Io has a light gravity pull, and added mass is desirable in the plane.
Braking rockets are not built into the plane because of the danger of opposing forces tearing the ship apart, or crushing it. Thus, water tanks are used in a unique method to halt the ship. The rocket tubes are so mounted that they can be swung around on the wings and reversed, jets pointing forward when a stop is desired. This brings the weight of the water in the rocket tubes to the rear, and to balance the ship the water in the rear tanks is diverted by means of pipes into the fuselage of the plane itself, more nearly at the center of gravity.
In case of an emergency landing, the rear water tanks keep the tail down, and allow the ship to glide in the snow without digging in. However, such landings are so infrequent that they are a matter of record by centuries rather than by year.
In maneuvering around mountains at low-level flying, diverting water from one tank to the other provide a constant and dep«idable method of controlling a turn, simply by the exact amount of mass that can be transferred to swing the ship around by the tail.
Constant temperature is maintained by diverted steam from the rockets.
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