The idea of aerial bombardment had to await the development of the airship and the airplane before it could become reality-a reality that soon became a nightmare for many after the First World War broke out in August 1914.
From the very beginning of the war, aircraft were used to drop bombs or heavy steel darts on enemy forces. With the exceptions of Germany’s use of zeppelins to drop bombs on Belgium and Britain’s bombing of zeppelin sheds-the destruction of which were aided by the hydrogen within the ships-the results of bombing early in the war produced more of a nuisance than anything else because of the lack of effective bombs and the limited carrying capacity of most early aircraft. The war, however, soon proved the adage that necessity is the mother of invention, as all powers, with varying degrees of success, began developing a new class of aircraft-the bomber- whose sole or primary purpose was to drop bombs on enemy troops or strategic positions deep behind enemy lines. As a result, the nature of the battlefield changed, making it three-dimensional by adding the attack from above, and extending its depth. In addition, the bomber blurred the lines between combatants and noncombatants. Although attempts were made to develop bombsights, these were crude and largely ineffective, making strikes against an intended target more a matter of luck than anything else. These problems were compounded as bombers and zeppelins were forced to operate at night because of their vulnerability to fighters. To the extent that civilians became “fair game,” the bomber helped usher in the era of total war.
After investing heavily in aircraft prior to the outbreak of the war, the French possessed a number of reconnaissance aircraft that were adapted for light bombing roles after the outbreak of the war. Among these were a series of Voisin pusher biplanes-designated Type 1 to Type 6 as more powerful engines were added-that were available at the outbreak of the war and entered service in the first 2 years of the war. Approximately 1,400 of all six types were produced in France, whereas Italy produced approximately 120 and Russia produced approximately 400. Of the Voisin types, the most commonly used for bombing purposes were the Type 3 and the Type 5, both of which had a wingspan of 48 ft 4.75 in. and a length of 31 ft 3.25 in. The Type 3 was powered by a 120 hp Salmson Canton-Unné radial motor, which produced a maximum speed of 62 mph, a ceiling of 2,743 m (9,000 ft), and an endurance of approximately 4 hours. It was armed with a Hotchkiss gun and could carry a bomb load of 330 lbs. The Type 5 was powered by a 150 hp Salmson Canton-Unné radial engine, which produced a maximum speed of 68 mph, a ceiling of 3,500 m (11,483 ft), and an endurance of 3 hours 30 minutes. Like the Type 3, it was armed with a Hotchkiss gun and could carry a bomb load of 330 lbs. Other reconnaissance aircraft that provided light bombing duties included the Nieuport 14 biplane, the Farman M. F. 7 and M. F. 11 pusher biplanes, and the twin-engine Caudron G. IV biplane.
The first French aircraft to see service primarily as a bomber was the Breguet-Michelin BrM4 biplane. It was based upon a Breguet BU. 3 prototype that had been developed in early 1914 and had been selected for production by André and Edouard Michelet, who had offered to build and donate 100 bombers for the Aviation Militaire. The BrM4 had a wingspan of 61 ft 8 in., a length of 32 ft 6 in., and a loaded weight of 4,660 lbs. Fifty were powered by a 200 hp Salmson Canton-Unné radial motor, which provided a maximum speed of 77 mph, whereas the other fifty were powered by a 220 hp Renault 8Gd inline engine, which provided a maximum speed of 84 mph. Both had a service ceiling of approximately 3,870 m (12,697 ft) and were capable of carrying forty 16-lb bombs in underwing racks. The BrM4 was also protected with either a Hotchkiss gun or Lewis gun. It entered service in late 1915 and served into 1916 before being withdrawn from the front and used as a trainer. The French also developed a variant, designated as the BrM5, which came equipped with a .37 mm Hotchkiss cannon. It was produced in small numbers, with most being sold to the British for service with the RNAS.
After concentrating primarily on building reconnaissance and fighter aircraft during the first 2 years of the war, the French military finally conceded to parliamentary demands and began development of aircraft specifically designed for service as bombers. Among the first to emerge from this effort were the Voisin Type 8 and Type 10 pusher biplanes. Both had a wingspan of 61 ft 8 in. and a length of 36 ft 2 in., but the Type 8 had a loaded weight of 4,100 lbs, whereas the Type 10 had a loaded weight of 4,850 lbs. The difference in weight was a reflection of the differences in engine and resulting bomb load capacity. Entering service in November 1916, the Type 8 was powered by a 220 hp Peugeot 8Aa inline motor, which produced a maximum speed of 82 mph and service ceiling of 4,300 m (14,108 ft), provided an endurance of 4 hours, and carried a bomb load of approximately 400 lbs. Entering service in late 1917, the Type 10 was powered by a 280 hp Renault 12Fe inline engine, which produced a maximum speed of 84 mph and a service ceiling of 4,300 m (14,108 ft), provided an endurance of 5 hours, and carried a bomb load of 660 lbs. Most Type 8 and Type 10 bombers were protected with one or two Hotchkiss guns, but some were equipped with a .37 mm Hotchkiss cannon. Approximately 1,100 Type 8 bombers and 900 Type 10 bombers were produced during the war. Even though they carried relatively small bomb loads and had to be used at night, their numbers provided some success in carrying out tactical missions against German troop concentrations and strategic missions against German transportation systems.
Introduced in September 1917, the Breguet 14 biplane provided the French with their most successful daytime bomber of the war; a large number were also used for armed reconnaissance and a few were even used as air ambulance aircraft. Although some of the early Breguet 14s were fitted with a 220 hp Renault inline motor, most were powered by a 300 hp Renault inline engine, which produced a maximum speed of 121 mph and a service ceiling of 5,800 m (19,029 ft), provided an endurance of 2 hours 45 minutes, and carried a bomb load of up to 520 lbs. The Breguet 14 had a wingspan of 48 ft 9 in., a length of 29 ft 1.25 in., and a loaded weight of 3,891 lbs. It was protected by one fixed, forward-firing, synchronized Vickers gun and two ring-mounted Lewis guns. A few were also fitted with a downward-firing Lewis gun and used to provide close ground support. By war’s end more than 3,500 Breguet 14s had been produced. An additional 5,000 were produced after the war until 1927. It remained in French service until 1932, seeing action in many colonial campaigns in North Africa and the Middle East. Numerous countries also purchased Breguet 14s for their air services in the 1920s.
Despite the pressure from French politicians, the French aircraft industry was slow to provide anything comparable to the heavy bombers being developed by other powers. This was partly because the army was more interested in fighters and reconnaissance aircraft and saw bombers as providing more of a supporting role for the infantry than a strategic role. Nevertheless, by late 1918 the French were experimenting with two prototype heavy bombers, the Caudron C. 23 biplane and the Farman F. 50 biplane. Although the former could carry a bomb load of approximately 1,750 lbs compared with the latter’s bomb load of approximately 1,100 lbs, the F. 50 was selected for production because of its superior climbing ability. Powered by two 275 hp Lorraine 8Bd inline motors, the F. 50 produced a maximum speed of 93 mph and could climb to 2,000 m (6,562 ft) in just 12 minutes 30 seconds. It had a service ceiling of 4,750 m (15,584 ft) and an endurance of 4 hours. The F. 50 had a wingspan of 75 ft, a length of 39 ft 5 in., and a loaded weight of 6,834 lbs. F. 50s began to enter service in early August 1918. Despite problems with the Lorraine engine, the F. 50 provided useful service during the Allied counteroffensive by bombing train stations and ammunition depots in a series of nighttime raids in October 1918. Approximately 50 were built by war’s end. After the war a few were sold to foreign powers. Although it came too late to make much of a difference in the war, the F. 50 did serve as the basis for the Farman F. 60 Goliath biplane, which was the main French bomber in the early 1920s.