A short history of bombers
The bomber is the ace of air power. The nation that can send the greatest number of first-line bombers over enemy territory, and can drop the heaviest weight of bombs consistently on military and industrial objectives, will win this global war.
The history of the bombing airplane is closely related with the history of war, but in the present conflict the bomber has played a more important part than ever before, and is likely to be the dominating factor in the achievement of ultimate victory. In 1942 bombing from the air attained its thirtieth birthday.
During the Balkan War of 1912, an English soldier of fortune named Snowdon Smedley, flying for the Italians, dropped a 100-pound bomb on the Turks. Of its effect we have no record, but he was the pioneer of attack from the air. We have progressed a long way since then.
Today the bomb aimer, which is the British term for bombardier, of a Halifax or Stirling, flying through dense clouds, fog and snow, can locate his target on the ground underneath by means of a "seeking" device, a combination of infra-red photography and television , and drop his bombs through the overcast with astonishing accuracy. No longer do the night bombing squadrons grope blindly through the darkness. Science has come to their aid, and provided the astonishing instrument that feels the contours of the ground and selects the target.
With his eye to the aperture of a powerful telescope through which he sees his target plainly framed between sighting hairs, and his finger controlling the knobs of the Norden or Sperry gyroscopic bombsight, the bombardier of an American high-altitude bomber can hit a target fifty yards in diameter from a height of 30,000 feet. Today young Americans are flying the war skies in huge armored battleships of the air, powered by four mighty engines , manned by a crew of eight to ten men. These streamlined monsters are precision built from nose to tail; they fight their way through the heavily defended skies of Axis territory, shooting down enemy fighters that challenge them, and wreaking terrible destruction on objectives below that would not be visible to the naked eye. A captured German prisoner told the intelligence department of the Eighth Air Force that he and his comrades could not understand the accuracy of American bombing, recalling how, after an attack on one target, the military objectives were destroyed completely while the hospital and civilian installations were unhurt except for blast.
The accuracy of modern bombing has been demonstrated repeatedly since the United States Army Air Forces went into action against our enemies. One of the first instances of this was the sinking of the Japanese battleship Haruna by Corporal Meyer Levin, the bombardier of the Fortress piloted by Captain Colin Kelly. Levin had three bombs in his bomb bay when the Haruna was sighted through the clouds. From 20,000 feet a battleship on the surface of the sea appears little bigger than our view of a small insect on the ground.
Levin, carefully and painstakingly trained in the United States Army bombardment school, took over the command of the plane, which is the prerogative of the bombardier when making an attack.
From that moment until he gives the signal "Bombs away" he is complete master of the aircraft. In this case Meyer Levin ordered his captain to come down to 18,000 feet. Levin then directed his run over the target, crossing the forward track of the Jap vessel. He unloosed his bombs as the ship came into the range of the sight. The first was a near miss, the second hit the Haruna smack amidships, the third grazed her side. It was remarkable shooting. It justified the United States Army Air Forces belief in precision bombing; it was a tribute to bombardier training and crew discipline. But it was only the beginning. Soon afterward from the Pacific came a report of how another bombardier, Lieutenant Smelser, sank or damaged six Japanese ships with eight bombs, an all-time high record for economy of weapons and precision aiming.
In the Battle of Midway, and later in the Coral Sea, American land-based bombers, supporting the onslaughts of torpedo and dive bombers, extracted a high toll from Japanese warships and transports . These early successes, however, were not perfection. They showed there was much to be done. Equipment had to be improved, tactics had to be evolved to meet unusual circumstances, and an ever-increasing amount of combat data had to be made available to the rapidly enlarging air forces. Of all weapons in this war the bomber has made the fastest and most effective progress, particularly the American bomber. The reason for this is that the United States alone, of all the belligerents, has the industrial facilities to build and modify planes while actually at war. The Army Air Forces make a practice of asking for modifications to existing types based on combat experience. These suggestions are forwarded to the Materiel Command which passes them on to the manufacturers, and the improvements are embodied in the machines before delivery.
It was recently revealed that no fewer than four hundred modifications were made in one type of bomber before the type itself reached the combat zone.
How these modifications are achieved without affecting production is one of the miracles of America's wartime ingenuity. In order to apply to new airplanes the requirements demonstrated by combat, the U.S.A.A.F. Materiel Command has dotted the nation with a series of modification centers. To these centers head the bombers direct from the production line. At each center are listed the improvements for each type as decided upon by the Materiel Command at Wright Field, Ohio. The planes are immediately passed through a miniature production line, where the changes are incorporated by specially trained Air Force ground crews, many of whom have had combat experience. Modifications may range from a new* angle setting for a supercharger to the fitting of a new plexiglas nose complete with guns and bombardier equipment. Routine adustments include the fitting of exhaust dampers for machines destined for night flying, the provision of equipment for arctic flights, and readjustment of gun positions, based on reports from overseas. In some cases additional bomb racks may be provided; other machines may be adapted for special photographic missions.
The system has many advantages. The chief of these is that it enables our warplanes to reach the combat lines absolutely up-todate . If the suggested modifications were executed on the actual production lines, valuable man hours would be lost while continual adjustment was being made to assembly equipment, to tools and jigs. In Germany and in England, where machines are manufactured almost under the shadow of the wings of enemy planes, this modification , which would require retooling and increase of man hours, is not always possible. In America it is a "must," and as such is responsible for the superiority of our bombardment forces.
Bombardment by airplane made its first real start in World War I. It was not very scientific, and it called for a great deal of courage on the part of the fliers, and some degree of skill. About it there was an element of sport, rather than precision skill. It was something like going hunting and taking a shot at a running deer with a .30caliber rifle, or shooting at a pigeon on the wing with an arrow.
Under certain conditions you obtained a hit; more often you did not. If you had to make a hit, you flew so low that you ran the risk of being blown up by the explosion of your own bombs, which sometimes happened.
The early bombing planes were actually built for reconnaissance purposes. The German and Allied armies prior to 1914 looked upon the airplane as the eyes of the army. Just as in 1870 the French and German armies sent up balloons to act as observation posts, so it was intended that the airplane fly over enemy territory to enable trained observers to spot the position of rival armies. In the early days both the sides used airplanes for this purpose, and when the rival planes met each other the pilots would greet each other with a wave of the hand.
The high commands on both sides, however, were thinking of bombing as an offensive weapon. In the United States and in Paris competitions had already been held to see if it was possible to obtain any accuracy of drop, and some astonishing results had been obtained. The British were the first to strike with the new weapon.
Four aviators attached to the British Navy set out from Antwerp in Belgium to bomb the Zeppelin shed at Diisseldorf and actually scored a direct hit, burning a huge gasbag which the enemy was doubtless preparing for raids on England. Another naval aviator flew to Cologne on the same day and hit the railway station, causing considerable alarm among the population, according to intelligence reports received.
The planes used were Sopwith biplanes. The bombs, which weighed twenty-five pounds, were crude affairs and were carried in racks underneath the fuselage. To release them the observer pulled out a pin, and down went the bomb, to which was attached a cloth tail to give it some degree of directional control. There were no bombsights , which meant that the fliers had to use their judgment, and fly as low as possible to be sure of hitting something. Shortly after the two successful sorties one of the same airmen lost himself over Germany and on returning aimed his bomb at a column of German troops. His aim was wild and the bomb fell in neutral Holland.
Immediately reports blossomed like daisies in summer that hundreds of women and children had been killed, the target allegedly being a church and a school. The incident had a sobering effect on the British public, however, and several spokesmen advocated stopping the practice.
The Germans were not long in replying. On Christmas Day, 1914, after the British had bombed the Zeppelin factory at Friedrichshafen , a lone German aviator flew over Dover and dropped the first bomb on the British Isles. It did no damage, but it was a symbol that the air arm was going to play rough. From that moment bombing became a recognized form of attack, although it was not for a good two years or more that bombs were dropped from airplanes with any degree of accuracy.
For the first year and a half the Germans were using Zeppelins, which made regular visits to England and Scotland. Their bombing , however, was of the terrorist kind, and did little real damage. The British could not retaliate by similar bombing of Germany.
All they could do was to shoot down the Zeppelins, which were highly vulnerable, being filled with inflammable gas. Night-flying planes and improved antiaircraft guns soon made the use of these airships too costly, so the Germans developed the Gotha bomber, probably the best bomber of the last war. Its outstanding feature was that the bombs and gasoline were massed round the center of gravity, making it extremely easy to fly. These Gothas made several daylight raids on Britain. Many were shot down by R.F.C. scout planes and antiaircraft guns. Then, as in this war, when British defenses and scout planes made it unprofitable for the Germans to make raids by daylight, they confined themselves to raids at night, or at dusk. In the latter days of the war the Gothas made a practice of coming over to bomb the airfields from which night bombers were operating. These raids were rendered ineffective by the simple procedure of constructing dummy airfields marked out with flare pots to draw the enemy bombs.
In many respects the pattern of air warfare in 1914-18 followed that of this present conflict. The British did not start their bombing until late in the war, and not until they had first worn down the enemy bomber and fighter strength. It was not until Sopwith triplanes and the FE-2b fighters, later to be used as bombers, had mastered the German Fokkers and Albatross scouts, that the British began to think of using the airplane as a bombardment support for ground forces. From the beginning of 1915 until the end of 1916 things were going badly for the Allies. The German scouts were mastering the skies, and the fields of Flanders were littered with broken wings.
Two machines did more than any others to turn the tide of battle. One was the FE-2b, a pusher biplane which had an extraordinary degree of maneuverability, even if it was slow. The outstanding feature of the FE-2b was that the observer or air-gunner sat in front of the pilot with a flexible machine gun, later with two on a single mounting. While the Germans with their new synchronized guns had to aim their machines at the target, as does the modern fighter plane, the FE-2b gunner had a wide range of fire. When attacked, the pilot of the FE-2b put his machine into a vertical bank, kept it there, turning tightly, and the gunner played havoc with the attacking German planes. The FE-2b had such a sturdy construction and weight-lifting ability that it was soon fitted with bomb racks, and thus combined the duties of bombing and fighting.
Then came the super-machine of the war, the Bristol fighter. A young flying officer named Frank Barnwell, who had been a designer of airplanes before the war, went to France and saw the destruction wrought by the Germans on the British planes. He returned to England with an idea. This was that if a plane could be designed which would be able to bomb by daylight as well as fight, air supremacy would be a matter of time and numbers of planes put into the air. Barnwell had seen many of his squadron mates shot down as a result of the enemy getting on their tails. He decided that the tail of a plane must be defended, and at the same time the pilot must have forward-firing guns to enable him to follow orthodox fighter practice. Barnwell had already designed a monoplane fighter which was years ahead of its time, but the Air Ministry had turned it down, because of its high landing speed. This time he was to produce a biplane that was needed. The men at the top of the Air Ministry believed in him, and he went to work to put everything he knew, everything he dreamed of, into the new plane.
In designing the plane, he had an additional incentive. His brother Harold, who had shared his early efforts to fly, had been killed in action with the Royal Flying Corps.
One day early in 1917 the new fighter-bomber arrived. The Bristol Fighter, as it was termed, was the last word in aerial efficiency.
Powered by a 250-hp. Rolls-Royce engine, it was a sturdy biplane with a humpback fuselage. The hump was the gunner's cockpit.
Here within talking distance of the pilot the gunner sat with a Lewis gun on a scarf mounting. His field of fire covered the entire rear of the plane, and if need be he could shoot forward and up, or forward and down. The pilot had two guns at his disposal, one a Vickers machine gun, the other a Lewis mounted on the top plane. Underneath the wings were bomb racks. The machine had the speed of the average fighter, a formidable dive, and could be thrown about with astonishing ease. How well Barnwell had succeeded was quickly demonstrated. R.F.C. pilots were crazy about their new mounts.
The first squadron equipped with Bristols was attacked by a formation of German Albatrosses, over Amiens. The Germans swept down with complete confidence. The Bristols turned to give battle still in formation, and shot down four of the enemy without loss.
That was the beginning. Soon the German scouts began to treat the Bristols with respect and the fame of the two-seater fighter became a legend.
In 1917 the British began to use the Bristols and the De Havilland as a similar type of machine for short distance daylight raids, employing the FE-2b as the medium distance night-raider. These machines, engaged in bombing railheads and dumps and troops, inaugurated the first regular program of strategic bombing which followed a definite pattern until the end of the war. The FE-2b could stay in the air for about three and a half hours and carry one 250-pound bomb and four 25-pounders. It was ideal for night flying , being extremely docile and capable of landing at low speed— about forty miles per hour.
Memories of night-bombing raids over Belgium and behind the German lines in France are still vivid to the writer. Day-flying pilots considered the night-flier as a miracle man, and a little bit of a crazy man for volunteering for such a "risky" operation, while we of the night-flying squadrons thought we had the softest job of the war, because we rarely encountered opposition more dangerous than antiaircraft fire, and searchlights which were easily avoided.
Our greatest danger at the time seemed to be the possibility of engine failure over enemy lines, and the difficulty of making forced landings at night. Some of us were lucky; those who were not did not survive to tell their experiences. The old FE-2b was a honey for night flying. Loaded to capacity with one 112-pound bomb, and two or four 2 5-pound bombs, it would stagger into the air after an astonishingly short run and take an amazing amount of punishment.
If a forced landing was necessary the machine could be put down on the proverbial handkerchief, and should it turn turtle it had the obliging habit of throwing the pilot and observer clear of the wreckage. Its water-cooled 120-hp. engine was as reliable as any, being capable of flying home with red-hot cylinders, fractured water jackets, and with shattered propellers.
Night bombing in those days was far from scientific. Ve flew with our senses and a little navigation. The observer was the navigator , the pilot the bomb aimer. We had bombsights which gave us the direction of our run, made into wind to avoid the effect of drift.
On arriving at the target area we used to fly around, spot what might or might not be the target—our ability to see it depended entirely on the visibility—and then let go the bomb or bombs. In some cases we dropped parachute flares to illuminate the ground below . On moonlight nights our work was comparatively easy; on cloudy nights it was exasperating. Weather conditions were the night-bombing squadrons' worst enemy. At take-off the sky would be cloudless, and half an hour later a thick fog would envelop the countryside. Night-landing fields were few and far between. The machines had radio for sending, not for receiving; if a pilot was lost, he had to find himself by the stars or landmarks, and get back as best he could. Yet losses were surprisingly low, and the results gratifying . This form of bombing continued until the signing of the Armistice.
In 1917 the British decided to carry the war to Germany and produced two bombers that had many of the features we find in the modern American bomber, which basically is without doubt the best in the world in all classes.
The first British long-distance bomber of note was the twinmotored Handley-Page, the same concern that today produces the giant Halifaxes. The first Handley-Page carried more than a ton of bombs, was armor plated, and powered by two 250-hp. Rolls-Royce engines. Later, fitted with 350-hp. motors and electrically operated bomb bays, other machines of this type flew regularly against German munitions plants in the Rhineland.
In the meantime the father of the modern bomber was being born. Handley-Page built a machine intended to bomb Berlin, to give the Germans a taste of what they had given London with their Gothas.
This was a big four-motored biplane capable of carrying six tons of useful load, including three tons of bombs, and a thousand gallons of gasoline which gave it a range of one thousand miles. During its test this remarkable machine took to the air over London with forty passengers. It went into production too late, however, for use against the Germans, but in subsequent operations the four-engined giant did good work in Irak, India, and Palestine.
Both the French and the Italians had also been steadily developing their big bombers. The Italians produced a three-engined Caproni with a formidable weight-lifting capacity. One of the most interesting features of this machine was that it had a double tricycle undercarriage, and landed with its tail up, just as do many of our own front-line bombers today.
Although few American planes got to France during World War I, the American conception of bombing, which is winning this war today, was born in France. General Billy Mitchell was operating with American-built but British-designed DH-9's, and with French Farmans . He came back to the United States with the profound conviction that bombing was the dominant factor in air power.
American industry, which had been building the DH-9a and the famous Packard Liberty motor that powered the 9a, was also concentrating on the production of bombers, and many outstanding types were produced. In most cases the designers were ahead of the materials at their disposal. Existing engines were heavy for the power they produced and construction materials were not adequate for the stresses imposed on them. The desire to produce a bomber with good clean lines and high performance was, however, predominant , and in the years immediately following the war the concept of the present American bomber was actually born.
Many remarkable machines were produced. The Curtiss Company , Glenn Martin, and other names now famous in our war production turned their attention to the building of bombers. One machine built in 1920 was powered by two motors giving 1000 hp. and carried three tons of bombs.
Another machine, the Gaulelet, was years ahead of its time. This was a low-winged single-engined monoplane which had everything but performance. Its construction was too flimsy, its engines too heavy. Only its design was good.
There was a night bomber with three 450-hp. Liberty motors, and the Barling bomber with six engines giving 2400 hp. Although it never went into service, this machine demonstrated that the United States could build big bombers as well as any other country.
By 1924 the United States Army had become bomber conscious and there began a long line of bombers that fathered the type in use today.
In 1925 the first Keystone bomber made its appearance. It had a 66-foot span and was powered by a single 800-hp. engine, and was fitted with machine guns for protection.
Then came the era of twin-engined bombers. The United States Army Air Corps decided that it needed bombers and not freak giants of unproven capabilities. The first of the planes to meet the demand was the famous Curtiss Condor, a twin-engined biplane with a high performance for its day. Then came twin-engined machines bearing such famous names as Douglas, Martin, Consolidated , Boeing, and Lockheed.
From 1927 onwards American designers concentrated on fast twin-motored ships. In 1932 Glenn Martin produced the B-10, with two 650-hp. Wright Cyclone motors, fastest medium bomber of its day, the forerunner of the now famous Maryland. From Tom Douglas 's all-metal ship with two supercharged Wright Cyclones, and capable of 210 miles per hour, we can trace the ancestry of the Boston and the Havoc, American-made bombers which have played an important part in the defense of Britain.
1934 saw the most important event in the history of American bombers, the birth of the Boeing Flying Fortress, which is without a doubt the best all-round aircraft in service today. We shall talk more about the Boeing later. Sufficient to say here that no other country can match it for performance and utility.
Modern bombers are divided into three classes: heavy, medium, and light or fighter-bombers, with the dive bomber, an early American invention, in the third class. Among America's heavies we have the Boeing B-17G and B-29 and the Consolidated B-24 Liberator , four-engined giants capable of carrying heavy loads over considerable distances. In the extra heavy class we have the experimental Douglas B-19 and the Martin Mars. British big fellows are the Short Stirling, Handley-Page Halifax, and Avro Lancaster. In the American medium class are the Martin B-26 Marauder, the Douglas A-20 (Boston or Havoc), and the North American B-25 Mitchell, that accomplished the famous raid on Tokyo.
In the light or dive-bomber class we have the Douglas Dauntless (the Army's A-24), the Vultee Vengeance, and the Curtiss Helldiver (the Army's A-25), which is said to be the most powerful dive bomber in any service.
In. considering all military airplanes we must remember one important fact. Each is a tailor-made job for a certain task. In some cases American-manufactured bombers have been pressed into service as fighters and have distinguished themselves because of their superior speed. An exceptional example of this is the Douglas Boston, used for short daylight raids over France by the R.A.F. and doubling as a night fighter. A slightly modified version of the A-20 distinguished itself as a fast low-flying attack plane in the North African campaign, and reports from Europe tell of its successful activity as a dive bomber.
The ideal bomber must be a good weight carrier. It must also have a long range, which means a large fuel-carrying capacity, and it must carry enough defensive armament to be able to beat off attacks from enemy fighters. In producing such machines the designer is faced with many problems. He must fit high lift wings to get a high power loading. In doing this he sacrifices maneuverability.
He must give his machine the greatest feasible speed and a high rate of climb and he must fit armor to protect pilot and crew against attack by enemy fighters.
The reason that the British have done the greater part of their bombing at night is because they designed their bombers to carry the greatest possible load over a comparatively short distance, eight tons over an 800-mile round trip at a medium altitude.
American heavy bombers were originally designed to carry smaller bomb loads at high altitude to engage in precision bombing.
Using turbosupercharged motors, they achieve heights above normal antiaircraft fire and attain a speed at high altitudes that nearly matches that of enemy fighter ships. Now with increased load capacity and armament and an ever-increasing range they carry the war to areas that would normally be out of reach.
While it is difficult to label any aircraft as the "best," there is no doubt that in heavy high-altitude bombers the United States has a corner on the world market.