SOME OF THE EFFECTS OF AN AIR ATTACK

Wanganui Chronicle, Volume 83, Issue 68, 22 March 1939, Page 3

SOME OF THE EFFECTS OF AN AIR ATTACK

Types of Bombs and Causes of Casualties

_£N the following article, which has appeared in the Lancet, Dr. P. H. Mitchiner and Dr. E. M. Cowell give many interesting facts concerning the effects of an air attack, types of bombs, and the cause of casualties. “ MODERN AIR FORCE has squadrons of heavy bombers capable of long-range flights at a height of 20,000 ft. and at a speed of 250 or more miles per hour, carrying 2-4 tons of bombs, and of medium bombers, which are much faster, can fly at 25,000 ft., and can carry a load up to 1 ton,” state Dr. Mitchiner and Dr. Cowell in the Lancet. “Composite formations of 27-36 machines—i.e., three or four squadrons—may be expected to arrive at such a height that they are almost invisible to the naked eye, even on a clear day. They can shut off their engines and approach their target under cover of clouds, swooping down with immense speed and completely surprising their victims. Repeated raids on the same locality are to be expected In Spain the main raid often takes place perhaps an hour after the first and after the ‘all clear’ signal has been given, when normal life is being resumed. “In Barcelona two distinct types of air-raids are recognised: the ‘objective’ raid, in which machines generally arrive at regular hours to bomb definite military targets, such as docks and barracks; and the ‘terror’ raid, in which machines either swoop down to attack crowded streets by day or arrive suddenly at night to interrupt the civil population at their pleasures or to disturb their night’s rest. Owing to the position of their base, the machines can approach from over the sea at a great height, swooping down silently on to the unsuspecting city. The first warning is often the first exploding bomb. “Three types of bomb may be used for inflicting damage on the civil population: high-explosive, incendiary, and gas. Occasionally machine-gun fire has been directed on trains or refugees crowding along the road. This is not likely to happen in this country, where

a well-organised defence against lowflying aircraft exists. “High-explosive bombs vary in size from 100 to 5001 b. are generally fitted with either a delayed-action percus-sion-fuse, enabling them to penetrate a tall building as far as the ground floor before exploding, or a contactfuse bursting higher up. “Occasionally bombs of 1000 kg. (equal to 1 ton) have been used. Some of the bombs used in Spain contain high explosive alone, whereas others contain shrapnel also. One type of bomb explodes on contact with the ground and makes a funnel-shaped pit, whose diameter and depth depend on its weight. Experts in Spain describe the following effects of bombs with delayed action fuses: — “(1) Penetration, depending on the weight of the bomb. “(2) Explosion, the action of the fuse transforming the explosive material | into gases. “(3) Destruction, spreading in a spherical manner, with a radius varying from 50 to 100 yards. “(4) Projection of fragments and shrapnel, up to 1,200 yards. “(5) Blast or pressure. “(6) Suction or aspiration, following (5) arid producing an even greater | effect. “(7) Commotion of the ground, like an earthquake. “(8) Fire, if there are inflammable materials near. “Casualties are due to people being trapped by falling masonry or injured in the resulting fires, to blast, or to flying glass or fragments of the bomb. No protection can be provided for a building against a direct hit. Air bombs generally fall obliquely and enter the building through one of the upper storeys. “If the bomb falls in a narrow street, the blast will kill without actually wounding. Casualties are picked up dead, without apparent wounds, and only showing blood-stained fluid trickling from the mouth or nose. Post mortem the lungs are found to be torn. The effect of blast on brick buildings is momentarily to push the walls in and then to suck them out so that the entire structure comes down, i

“In steel-frame buildings the walls are affected in the same way, leaving; the floors and perhaps the upper parts still standing. The steel uprights are twisted but remain standing with the floors intact. Ferro-concrete stands up best against these effects. A bomb falling on a hard surface in an open space will scatter fragments with an effective range up to 1,200 yards. The casing of the bomb bursts into small fragments, usually smaller than shell fragments. “They are, however, impelled by a greater force and in consequence do vastly more damage. A fragment the size of a pea, with a minute wound of entry, will comminute a bone. A publication may shortly be issued by the British Government describing the effects of high-explosive bombs, as observed from experimental bombing of buildings from the aid. . . . “The use of incendiary bombs has been discontinued in Spain, because the buildings are resistant, the fire services are efficient, and so many of the bombs have failed to explode. One type of thermite bomb used in Spain has a ribbed band at its base which is blown off on reaching its destination, allowing the powder to escape, blaze, and splutter. “It has recently been discovered that, if located immediately and covered by | a fine spray of water pumped by hand from a bucket, the bomb and its immediate surroundings may be kept cool and no general fire will result. One bomber can carry a thousand 1-kg. incendiary bombs and scatter them over a belt a hundred yards wide and three miles long in about a minute. In a town half of these will probably strike buildings and start fires. A fireproof paint has recently been described which will soon be on the market. “Gas has not so far been used in Europe in air attacks. Both persistent and non-persistent gases might be used, either by being dropped in containers or as clouds sprayed from the air. Protection, however, is easier to obtain than in the case of either highexplosive or incendiary bombs. In Great Britain each person has his respirator ready, and the public is well informed on the matter. A.R.P. schemes have been prepared everywhere, and it is unlikely that panic would result.”