Amphibious aircraft

“ An airship can be anchored more easily with the point against the wind on water. It is quite impossible to anchor on land when assistance is not forthcoming to hold down the airship. On water, also, the airship will give a little to side winds and to alterations in the direction of the wind, without overturning. On land this danger is not excluded, even with rigid airships. Of course, a watertight and seaworthy car is a necessary condition for landing on water. ”

“ But the navigation of the air, whether by airship or aeroplane, is now recognized for the more formidable novelty. The progress of the war has proved that within the narrow seas the submarine can be countered, and that the extension of its capabilities on the high seas is beset with difficulties. For aircraft the possibilities are immense. It is not extravagant to say that the 17th of December 1903, when the Wright brothers made the first free flight through the air in a power-driven machine, marks the beginning of a new era in the history of the world. ”

“ The aeroplane and the air-ship are recent accessions to the list of fighting craft. Their rôle in naval warfare cannot yet be defined, because the machines themselves have not yet reached an advanced stage of development, and their probable performance cannot be forecast. There is no doubt, however, in the minds of naval men that the rôle of aircraft is to be important and distinguished. ”

“ Emphasis has been laid on the changes in the design or construction of aeroplanes and dirigibles, which show the evolution of flight and aircraft from early experiments with balloons and gliders to the transatlantic flights of the NC-4, the Vickers “Vimy” Bomber, and the R-34. Only those things have been singled out which indicated a step forward in the science of aeronautics. Emphasis is placed upon the commercial accomplishments of the aeroplane and the dirigible, and many of the present uses and future possibilities of aircraft as a commercial vehicle have been pointed out. ”

“ They are endowed with sustaining power and stability.
As the envelopes of airships are filled with a gas which lifts and sustains, the great disadvantage of instability which is the bugbear of aëroplanists is absent. If engines break down or stop, it does not necessarily mean that the airship must immediately descend. It can often remain in the air while the machinery is being repaired. ”

“ For example, if the tail plane or flat, finlike surface that projects from the sides of the tail of the body, or fuselage, has too much “incidence,” or, in other words, is slanted at too sharp an angle downward, it has a tendency in flight to lift the rear of the machine and to make it dive. A seaplane, when properly constructed, is so evenly balanced that, when the crane that lifts it off the mother ship holds it suspended in the air, the machine is equipoised like a bird with wings spread in flight. ”

“ Naval aviation is a specialized problem. It involves not only the relatively simple problem of flight operations with aircraft, but also combined with this are the more complex problems of utilizing aircraft under the practical conditions of naval warfare. Planes must be used offensively and defensively in naval manoeuvres a thousand or more miles from a land base. They must operate from surface ships and must be closely coordinated with the plane and manoeuvres of the fleet organization. ”

“ It is no easy trick at first, to control the "penguin" and keep its course direct. Then he will try the "jumps" in a machine that leaps into the air and descends automatically after a twenty to forty yards' flight. As Darius Green expressed it so long ago, the trouble about flying comes when you want to alight. That holds as true to-day with the most perfect airplanes, as in boyhood days when one jumped from the barn in perfect confidence that the family umbrella would serve as a parachute. ”

“ The flying-boat has one large boat instead of a fuselage, with a small pontoon on the end of each wing. The former is used for fast flying, but owing to the air resistance to the pontoons, and especially to the boats, the speed cannot be compared to that of the scout aeroplanes. Moreover, they are much harder to do stunts with and few are known to have looped the loop. Like the big land bombers the flying-boats may be equipped with as many as three motors. One of these has carried as many as fifty passengers at one time. ”

“ No one who has considered rigid airship design and studied rapid strides which aeroplanes have made in the last three and a half years can doubt for a moment that an airship could be built in the course of the next two years which would have a disposal lift—or, [224] in aeroplane parlance, a ‘useful load’—of over two hundred tons, giving it an endurance of anything up to three weeks at a speed of forty to forty-five miles an hour. ”

“ France must be credited with at least eighteen airships of various types—England had only seven—Russia had probably not more than three airships available—Belgium had one airship Austria had not less than three, not more than five airships available—Germany had twenty three airships of the rigid, semi-rigid, and non-rigid type. ”

“ Steering was done by means of rudder or the engines, or both, and the airship was kept on an even keel by use of lateral planes. The airship could be brought down by forcing the gas out of the bags into the gas-tanks, thus decreasing the volume, and by increasing the air in the various compartments.
This airship had a flying radius of 800 miles, could climb to 12,000 feet, could carry a useful load of 30 tons, and could remain in the air for 50 hours. ”

“ The rear end of the keel is expanded into fixed vertical and horizontal fins, and carries a vertical and a horizontal rudder.
The rear end of the gas bag is fitted with thin fixed planes (compare with the pear shaped or tubular fins of the "Astra" class) .
The cars are provided underneath with an extraordinarily strong conical structure, which takes the shock of striking the ground and distributes it over the whole car.
Aeroplanes are now fitted, one each side of the keel, well forward. ”

“ It is no exaggeration to say that the ground manipulation of large airships necessitates the73 attendance of quite an army. In the case of a Zeppelin the exigencies of wind may call for the assistance of 300 trained sappers on landing. This is the reason why it is so advisable to have the resting-places of large airships on water. In the case of rigid airships a slight bump on the earth may do considerable damage. ”

“ Displacement, size, motive power, speed, radius of action, and armament were gradually increased until the "E" class contained boats possessing the following features: Submerged displacement, 800 tons; length 176 feet; beam 22-1⁄2 feet; heavy oil engines of 2000 H.-P.; electric engines of 800 H.-P.; surface speed 16 knots; submerged speed 10 knots; cruising range 5000 miles; armament: 4 torpedo tubes, space for 6 torpedoes, and two 3-inch quick-firing, high-angle, disappearing guns; armoured conning-towers and decks; wireless equipment ”

“ For vertical steering there are sixteen planes provided in sets of four on each side of the front and rear ends of the balloons. These can be independently inclined upwards or downwards. When the forward ones are inclined upwards and the after planes downwards, the reaction of the air on the planes as the airship is driven forwards causes the front part to rise22 and the rear part to sink, and the airship is propelled in an inclined direction to a higher level. ”

“ So far as the scouting aeroplane is concerned, the obvious solution to the difficulty is the provision of a floating aeroplane base, capable of accompanying, or acting in co-operation with, the fleet on the high seas, or of acting independently if required. ”

“ With the huge wing-like planes expanded to the full, the Ocean Flyer coasted aslant the air-waves. The cloud belt encircling the globe was penetrated and passed through, leaving small drops of moisture glistening all over the glass of the portholes. The moon’s rays made the metal body of the vessel [77] glitter like so much silver. As they dropped lower and lower, the world became dimly visible, seeming to be literally rising to meet the descending aviators. At an altitude of three thousand feet, the downward planing was discontinued and level flight again maintained. ”

“ On the other hand, the airship, being provided with engines to propel it through the air, and with rudders and elevators to control it for direction and height, can be steered in whatever direction is desired, and voyages can be made from one place to another--always provided that the force of the wind is not sufficiently strong to overcome the power of the engines. ”

“ As if the occupants of the airship had heard the words of the aged inventor, they headed their craft toward earth. The combined aeroplane and dirigible balloon, a most wonderful traveler of the air, swung around, and then, with the deflection rudders slanted downward, came on with a rush. When near the landing place, just at the side of the house, the motor was stopped, and the gas, with a hissing noise, rushed into the red aluminum container. This immediately made the ship more buoyant and it landed almost as gently as a feather. ”

“ Owing to its ceiling, rate of climb and speed, which we take to be from 70 to 80 miles per hour in the airship of the future, the airship may be regarded as comparatively safe against attack from the ordinary type of seaplane. The chief danger to be apprehended is attack from small scouting seaplanes, possessing great speed and the power to climb to a great height, or from aeroplanes launched from the decks of ships. ”

“ The arrangements made for handling airships on the ground and while landing, and also for moving them in the open, provide scope for great ingenuity. An airship when about to land is brought over the aerodrome and is "ballasted up" so that she becomes considerably lighter than the air which she displaces. ”

“ Thirdly, there is the streamline envelope with tangential suspensions, which has been adopted for all classes of the S.S. airship, and which has proved for its purpose in every way highly satisfactory.
Of these three types the rigid has the inherent disadvantage of not being able to be dismantled, if it should become compelled to make a forced landing away from its base. Even if it were so fortunate as to escape damage in the actual landing, there is the practical certainty that it would be completely wrecked immediately any increase occurred in the force of the wind. ”

“ Owing to the clearness of the water in tropical regions, objects can be located at a great depth when viewed from the air, and it is imagined that an airship will be of great assistance in searching for likely places. Sponges and coral are also obtained by diving, and here the airship's co-operation will be of value. Small ships such as the S.S. Zero would be ideal craft for these and similar operations. ”

“ A non-rigid airship in a nasty wind can land and deflate itself at once by ripping the panel in the envelope, at no greater price than the loss of its gas, and probably some damage to its car. To land in a rigid ship is at best a ticklish business; indeed, the rigid airship is in exactly the same case as a large sea-going vessel; its chief dangers are from the land, which it cannot touch with impunity. ”

“ Yet another point in favor of the airship as a medium for trans-ocean flight is its greater safety. An aëroplane is entirely dependent for sustentation in the air on the proper working of all its motors. Should two motors—in some cases even one—break down, the result would be a forced descent into the water, with the possibility of total loss on a rough sea, even though the craft be a solid flying boat. In the case of an airship the only result of the failure of any of the motors is reduction of speed. ”

“ Experience in the war has proved that for military purposes the large rigid, capable of long hours of endurances and the small non-rigid made thoroughly reliable, are the most valuable types for future development. The larger non-rigids, with the possible exception of the North Sea, do not appear to be likely to fulfil any very useful function.
Airship design introduces so many problems which are not met with in the ordinary theory of structures, that a whole volume could easily be devoted to the subject, and even then much valuable information would have to be omitted from lack of space. ”

“ The airship is, therefore, nothing else than a dirigible balloon, for the engines and other weights connected with the structure are supported in the air by an envelope or balloon, or a series of such chambers, according to design, filled with hydrogen or gas of some other nature. ”

“ As my air-ship ploughed ahead the wind struck my face and fluttered my coat, as on the deck of a transatlantic liner, though in other respects it will be more accurate to liken aerial to river navigation with a steamboat. It is not like sail navigation, and all talk about "tacking" is meaningless. If there is any wind at all it is in a given direction, so that the analogy with a river current is complete. When there is no wind at all we may liken it to the navigation of a smooth lake or pond. ”

“ The submarine will not be the only danger to be guarded against from an unexpected quarter. The aeroplane and airship will play their parts in the next naval war. Experiments have already been tried in starting a flight of an aeroplane from a platform at the bows of an American warship, and this being accomplished, it is not too much to anticipate that aeroplanes for purposes of observation or attack may become part of the equipment of every battleship or large cruiser. ”