The Breguet Br 4 and 5 series of aircraft were the products of a French government specification calling for a bomber capable of carrying 300kg of bombs over a range of 600km. The specification was itself a product of pressure form the Michelin brothers (who owned the tyre company) who argued that the French ought to be able to carry out bombing raids on enemy territory.
The Breguet pusher design was chosen to meet the specification and the Michelin brothers offered to build and donate 100 of the type provided that the French government paid for the engines. By November 1915 47 examples had been delivered. The slow rate of production was caused, as so often was the case with aircraft at this time, by delays in the manufacture of the engines.
In common with other pusher types the delays meant that by the time the machines reached front line squadrons they were becoming obsolete, and the Breguet pushers were no exception. In addition many pilots had accidents when attempting to learn how to handle these pushers, so that the machine was never popular. By the time sufficient numbers were in service to allow day raids to take place the type was too slow and too vulnerable to be used, and after only a few sorties the type was withdrawn from daylight raids.
The Br M 4 had Michelin designed bomb containers under the wings and was provided with a Lewis or Hotchkiss machine gun for the observer in the front cockpit. The Br 5 was intended to act as an escort to the bombers and was armed with a 37mm cannon in the front cockpit: frequently this was replaced with a machine gun. A second gun was provided for the observer which was mounted on rails so that it could fire over the head of the pilot and over the top wing. Needless to say this arrangement was ineffective in defence from attacks from below and the type was never widely used as a fighter. When the type was withdrawn from day bombing it was used for night bombing instead, where it served with the French until January 1918.
The RNAS bought 30 Breguets from France and an additional 10 were built by Grahame White and powered by Rolls Royce 250hp engines. These served with no 3 Wing in the Dunkirk area and some were sent to the Aegean, but they too were never popular with their crews as they were too slow and difficult to land.
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