The attitude of the fighting airmen is somewhat reminiscent of that of America's greatest sea-fighter, Admiral Farragut. Always opposed to ironclads, the hero of Mobile Bay used to say that when he went to sea he did not want to go in an iron coffin, and that when a shell had made its way through one side of his ship he didn't want any obstacle presented to impede its passing out of the other side.
[Illustration: © U. & U.
Launching a Hydroaëroplane.]
The all important and even vital necessity for speed also detracted much from the value of aircraft in offensive operations. It was found early that you could not mount on a flying machine guns of sufficient calibre to be of material use in attacking fortified positions. If it was necessary for the planes to proceed any material distance before reaching their objective, the weight of the necessary fuel would preclude the carriage of heavy artillery. In the case of seaplanes which might be carried on the deck of a battleship to a point reasonably contiguous to the object to be attacked, this difficulty was not so serious. This was demonstrated to some extent by the British raids on the German naval bases of Cuxhaven and Wilhelmshaven, but even in these instances it was bombs dropped by aviators, not gunfire that injured the enemy's works. But for the airplane proper this added weight was so positive a handicap as to practically destroy its usefulness as an assailant of fortified positions.
The heavier weapons of offence which could be carried by the airplane even of the highest development were the bombs. These once landed might cause the greatest destruction, but the difficulty of depositing them directly upon a desired target was not to be overcome. The dirigible balloon enjoyed a great advantage over the airplane in this respect, for it was able to hover over the spot which it desired to hit and to discharge its bombs in a direct perpendicular line with enough initial velocity from a spring gun to overcome largely any tendency to deviate from the perpendicular. But an airplane cannot stop. When it stops it must descend. If it is moving at the moderate speed of sixty miles an hour when it drops its missile, the bomb itself will move forward at the rate of sixty miles an hour until gravity has overcome the initial forward force. Years before the war broke out, tests were held in Germany and France of the ability of aviators to drop a missile upon a target marked out upon the ground. One such test in France required the dropping of bombs from a height of 2400 feet upon a target 170 feet long by 40 broad--or about the dimensions of a small and rather stubby ship. The results were uniformly disappointing. The most creditable record was made by an American aviator, Lieutenant Scott, formerly of the United States Army. His first three shots missed altogether, but thereafter he landed eight within the limits. In Germany the same year the test was to drop bombs upon two targets, one resembling a captive Zeppelin, the other a military camp 330 feet square. The altitude limit was set at 660 feet. This, though a comparatively easy test, was virtually a failure. Only two competitors succeeded in dropping a bomb into the square at all, while the balloon was hit but once.
The character and size of the bombs employed by aircraft naturally differed very widely, particularly as to size, between those carried by dirigibles and those used by airplanes. The Zeppelin shell varied in weight between two hundred and two hundred and fifty pounds. It was about forty-seven inches long by eight and a half inches in diameter. Its charge varied according to the use to which it was to be put. If it was hoped that it would drop in a crowded spot and inflict the greatest amount of damage to human life and limb it would carry a bursting charge, shrapnel, and bits of iron, all of which on the impact of the missile upon the earth would be hurled in every direction to a radius exceeding forty yards. If damage to buildings, on the other hand, was desired, some high explosive such as picric acid would be used which would totally wreck any moderate-sized building upon which the shell might fall. In many instances, particularly in raids upon cities such as London, incendiary shells were used charged with some form of liquid fire, which rapidly spread the conflagration, and which itself was practically inextinguishable.