Royal Aircraft Factory: B.E.12
Note: This is a sub-section of Royal Aircraft Factory.
The Royal Aircraft Factory B.E.12 was a British single-seat aeroplane of the First World War designed at the Royal Aircraft Factory. 601 were built.
The B.E.12 was essentially a B.E.2c with the front (observer’s) cockpit replaced by a large fuel tank, and the 90hp Royal Aircraft Factory 1 engine of the standard B.E.2c replaced by the new 150 hp RAF 4.
Aviation historians once considered the type purely as a failed attempt to create a fighter aircraft based on the B.E.2 - that was hastily improvised, and rushed into service to meet the Fokker threat.
The prototype (a modified B.E.2c airframe fitted with the more powerful 150hp (112 kW) RAF 4a air-cooled V12 engine) was already in the process of conversion in June 1915, while the Fokker scourge cannot be said to have started before the first victory by a Fokker E.I, on the 1st of August, when Max Immelmann shot down a British aircraft that was bombing Douai aerodrome. At the time the B.E.12 was conceived the necessity for a warplane to be able to defend itself in the air was by no means as clear as it became later – certainly the new type cannot have been produced specifically as an “answer” to the Fokker.
In mid 1915 there was as yet no way for a British single seat tractor aircraft to carry an effective forward firing armament – as the Vickers-Challenger “interrupter” gear did not exist until December, and was not available in numbers until the following March. The latest Royal Aircraft Factory single seat fighter of the time, the F.E.8, was a nimble little pusher.
Trials with the B.E.12 prototype continued through late 1915 – and seem to have been mainly concerned with the development of the new RAF 4 engine, especially the design of a satisfactory air scoop. Cooling of the rear cylinders of the RAF 4, an air-cooled V12, and later the power-plant of the R.E.8, was always rather problematic. The type was also tested as a bomber.
It was May 1916 (when the "Fokker scourge", as a period of real German air superiority, was over) that it was decided to fit a synchronised Vickers gun to the type – although armament trials had already been undertaken with upward firing Lewis guns, similar to those used by the night fighter version of the B.E.2c.
The B.E.12a variant flew for the first time in February 1916 and had the modified wings of the B.E.2e. It was rather more manoeuvrable than the B.E.12, but was otherwise little improvement.
The B.E.12b used the B.E.2c airframe but had the 200 hp Hispano-Suiza engine. It was intended as a pure night fighter, and carried wing mounted Lewis guns in place of the synchronised Vickers. Apparently it had a good performance, but the engine was more urgently needed for the S.E.5a and very few B.E.12b fighters went into service with home defence squadrons. Some of those built may in fact never have received engines.
The first B.E.12 squadron, No. 19, did not reach France until the 1st of August 1916. It was followed by the only other squadron to fly the type in France, No. 21, on the 25th of the same month. As might have been expected, the new type had all the inherent stability of the B.E.2c and was quite useless in the fighting role, especially in the face of the new German Halberstadt and Albatros fighters then coming into service.
It continued to be employed as a bomber – but since an effective defensive gun could not be mounted it was too vulnerable for this role, and was finally withdrawn from all front line duties in France in March 1917. By the time the B.E.12a became available in numbers the B.E.12 had already proved to be unsatisfactory, and this variant was never used operationally in France.
Several Home defence squadrons flew B.E.12s, along with examples of the B.E.12a and B.E.12b variants. Its stability and range were obvious advantages in an aircraft that had to fly at night, but its rate of climb was inadequate when called on to intercept aeroplane raiders. The Zeppelin L.48 was shot down by a Home Defence B.E.12 on the 17th of June 1917 – but otherwise there are few recorded successes of the type in this role.
In the Middle East theatre, and in Macedonia, the B.E.12 and B.E.12a proved more useful – although typically as long range reconnaissance aircraft rather than as fighters. An exception to this rule was the machine of Captain G.W. Murlis-Green of No. 17 Squadron – who shot down several enemy aircraft, probably the only B.E.12 ace!
The B.E.12b served only with Home Defence squadrons - deliveries began in late 1917.
- B.E.12 - Initial production version powered by a RAF 4a engine - basically a B.E.2c conversion (250 built by Daimler, 50 built by Standard Motors)
- B.E.12a – With the wings and tail unit of the B.E.2e (50 built by Daimler, 50 built by Coventry Ordnance Works)
- B.E.12b - Re-engined version powered by a 200hp (149 Kw) Hispano-Suiza engine (200 built by Daimler)
Sources of Information
- The Royal Aircraft Factory by Paul R. Hare. ISBN 0-85177-843-7
-  Wikipedia