В.Кондратьев Самолеты первой мировой войны
Осенью 1915 года, в ответ на появление на Западном фронте первых истребителей Фоккера многие британские авиаконструкторы спешно начали создавать машины, способные противостоять этой угрозе. Инженеры завод РАФ решили сделать истребитель на базе BE.2. Опытный экземпляр, получивший индекс BE.12, построили к концу года путем переделки одного из серийных BE.2.
Переделка свелась к минимуму. Самолет оснастили гораздо более мощным 150-сильным мотором РАФ 4а, а экипаж сократили до одного человека. Вооружение составлял один пулемет "Льюис", размещенный на левом борту фюзеляжа. Его испытывали как в синхронном, так и в несинхронном варианте (с отсекателями пуль на лопастях винта). Предпочтение было отдано варианту с синхронизатором.
На серийных экземплярах, вместо "Льюиса", ставили синхропулемет "Виккерс" с ленточным питанием. В качестве альтернативного варианта иногда применялся несинхронный курсовой "Льюис", установленный над верхним крылом для стрельбы поверх винта, но из-за невозможности перезарядки в полете этот вариант не получил распространения.
Самолет запущен в серию в мае 1916 года, после того, как опытный экземпляр прошел испытания на боевое применение во Франции. 25 августа первый английский дивизион, укомплектованный BE.12, был отправлен на фронт, а уже в середине сентября из-за тяжелых потерь эту часть отвели в тыл. Дело в том, что самолет, создававшийся как оппонент "Фоккеру", оказался морально устаревшим уже к моменту вступления в бой. Его летные характеристики не позволяли драться на равных с новыми немецкими истребителями "Альбатрос" и "Хальберштадт".
Даже оснащение BE.12 еще более мощным 180-сильным двигателем "Испано-Сюиза" не помогло улучшить ситуацию. Для одноместного истребителя он был слишком переразмеренным, тяжелым и слабоманевренным.
Самолет переклассифицировали в легкий фронтовой бомбардировщик (установив подвески для 100 кг. бомб) и в ночной истребитель ПВО (с дополнительными пулеметами "Льюис" на "лафетах Стрейнджа"). Некоторые экземпляры передали в патрульные дивизионы береговой обороны и в летные школы.
В качестве бомбардировщика машина применялась до середины 1918 года, преимущественно, на второстепенных фронтах. Более сотни машин, (из них 36 - с "Испано-Сюизами"), в 1917-18 годах входили в состав ПВО Великобритании. На некоторых из них количество дополнительных пулеметов, установленных под углом вверх, доходило до четырех! Также иногда применялись ракеты "Ле-Прие".
Всего построено примерно 600 BE.12. Около 500 из них - на заводе английского филиала фирмы "Даймлер". Еще по 50 экземпляров выпустили фирмы "Ковентри Орднэнс Уоркс" и "Стандард Мотор Компани".
BE.12а - полуторапланная коробка крыльев.
ВЕ.12b - двигатель "Испано-Сюиза", 180 или 200л.с.
Размах, м 11,28
Длина, м 8,31
Высота, м 3.39
Площадь крыла, кв. м 34,5
Сухой вес, кг 742
Взлетный вес, кг 1067
Скорость максимальная, км/ч 156
Время набора высоты
2000 м, мин. 18
Потолок практический, м 3810
Продолжительность полета, ч 3
Экипаж, чел 1
P.Hare Royal Aircraft Factory (Putnam)
Conceived about May 1915, when the B.E.2c continued to be the most effective aeroplane operated by the RFC and serious aerial combat was still a thing of the future, the design which became known as the B.E.12 was intended to give improved performance for roles such as bombing or photography, for which an observer was not usually carried. That it was not, initially, intended as a fighter is perhaps most clearly illustrated by the fact that the type had been in production for several months before any attempt was made to fit a gun to it.
The prototype was created by the conversion of standard production Bristol-built B.E.2c 1697. The front cockpit was eliminated, and the engine bearers were modified to accept the 140hp R.A.F.4 V-12 engine. This had separate exhaust pipes from each cylinder, and they were led to a single vertical exhaust stack in the form of an inverted 'Y' on the aeroplane's centreline, where it can have done nothing to improve the pilot's forward view. Twin air scoops were mounted in tandem in the cylinder-head vee to assist engine cooling. A large pressurised fuel tank, shaped to follow the line of the fuselage top decking, was mounted between the centre-section struts. The skid-equipped undercarriage with which 1697 had originally been fitted was replaced by the more modern vee-strut type.
This work was completed by 28 July, when the machine was presented for its preflight inspection, and testing and development proceeded at a fairly unhurried pace thereafter. By the end of August a large, single air scoop had been fitted, necessitating the division of the exhaust into separate stacks for each cylinder bank.
The B.E.12 remained at Farnborough for most of the next month, supposedly for bomb-dropping experiments, although no evidence has been found of a bomb rack being fitted. On 22 September a larger, curved fin, as was to become standard for later B.E.2s, was fitted, and 1697 then went to France for service trials.
Production orders were placed with the Coventry Ordnance Works, the Standard Motor Company and Daimler, the last also undertaking production of the R.A.F.4a engine. Perhaps coincidentally, all three companies were based in Coventry.
Delays in engine manufacture held up completion of the first production B.E.12 until late March 1916, when Daimler-built 6478 arrived at Farnborough. Production aircraft differed from the prototype in having their upper fuselage longerons set down to a lower level forward of the cockpit, the engine mounting being similarly lowered. This improved the forward view over the engine air scoop, and allowed a larger petrol tank to be fitted. A streamlined gravity tank was also provided, under the port wing. Early examples had the original triangular fin, a larger fin of a type already fitted to 1697 being introduced later. All production machines were equipped with a camera mounting on the starboard side of the fuselage, outside the cockpit.
The prototype remained at the Factory and, from March 1916, was fitted with a number of experimental gun installations. Since there was still no British synchronisation gear, the initial installation, using a Lewis gun, featured blocks fitted to the propeller to deflect bullets. A later installation had the six-pounder Davis gun firing upwards at an angle of forty-five degrees, the muzzle being level with the top wing to place the breech within easy reach of the pilot. This was presumably intended for use against high-flying Zeppelins, but it was not adopted for service use.
Finally, the newly developed Vickers-Challenger interrupter gear was adopted, operated a belt-fed Vickers machine gun mounted on the port side of the fuselage. The engine's air scoop prevented its installation in the favoured position on top of the decking, immediately in front of the cockpit. This fuselage-side mounting made jam clearing difficult, as the pilot had to reach far outside the cockpit. Unfortunately the sights also needed to be positioned on the aircraft's side for the same reason, forcing the pilot to lean out into the slipstream to take aim.
In mid-1916, in the wake of the 'Fokker scourge', the B.E.12 was pressed into service as a fighter, but its use in this role was soon curtailed following reports that it lacked even the limited manoeuvrability of the B.E.2c. In July the smaller tailplane designed for the B.E.2e was adopted for the B.E.12, and brought some improvement in handling, but the type quickly returned to the bomber role for which it had been designed, and in which it continued until February 1917.
Like the B.E.2c from which it was derived, its stability made it eminently suitable for use as a night fighter. It replaced the B.E.2c in this duty, and its greatest success occurred on 17 June 1917, when Lt L P Watkins of No 37 Squadron, flying 6610, brought down the Zeppelin L48.
Experiments in rendering aeroplanes less visible led, in February 1917, to the rear fuselage of 6148 being covered in transparent celluloid instead of fabric, but a lack of success is suggested by the early termination of the experiment.
Like many machines designed in the early part of the war, the B.E.12 continued in service for longer than its suitability dictated, new and less demanding roles being found as obsolescence approached. Thus the B.E.12 served almost to the end of the war as a trainer and on anti-submarine patrols, for which duty it was usually armed with two 112lb bombs.
The uprated R.A.F.4d, developing 200hp, was fitted to B.E.12 C3188 at the Orfordness experimental establishment, but no details of improvements in performance are available.
Powerplant: 140hp R.A.F.4a V-12
span 37ft 0in;
chord 5ft 6in;
gap 6ft 3 1/4in;
wing area 354sqft;
dihedral 3 1/2;
stagger 2ft 0in;
incidence: 4° 9''.
length 27ft 3in;
height 11f t 1 1/2in.
max speed 102mph at sea level;
97mph at 6,000ft;
6min to 3,000ft;
14 min to 6,000ft.
Since the B.E.2e was viewed, at the time of its inception, as being almost infinitely superior to previous variants, it was inevitable that the B.E.12 should also be modified to have the new unequal-span wings. In this form the machine was initially designated the B.E.12Ae, but this was quickly simplified to the more conventional B.E.12a. Production orders, each for fifty aircraft, were placed with Daimler and the Coventry Ordnance Works.
The B.E.12a was initially judged to be easier to land and manoeuvre than its two-bay predecessor but, in reality, it showed little improvement over the earlier type and its use was largely confined to Home Defence units and the less-demanding theatre of operations in the Middle East. Some also served with the Royal Australian Air Force.
In November 1916 a new set of wings was constructed which had increased tip rake and included ailerons, incorporating large balance areas, on the top wing only. These wings were fitted to 6511, which had originally been built as a B.E.12, and on the 13th of that month Frank Goodden began flight tests. These showed no significant improvement in performance, and were reported to render the handling characteristics 'unpleasant', so the design was dropped, although a similar wingtip plan was reintroduced with the F.E.9.
Powerplant: 140hp R.A.F.4a V-12
40ft 6in (upper);
30ft 6in (lower);
chord 5ft 6in;
stagger 2ft 0in;
gap 6ft 3in;
wing area 360sq ft;
length 27ft 3in;
height 12ft 0in.
max speed 105mph at sea level;
93mph at 6,000ft;
5min to 3,000ft;
11 1/2min to 6,000ft.
Despite occasional successes by Home Defence squadrons, Zeppelin raids continued to cause widespread concern, and the raiders usually escaped simply because the defending aeroplanes lacked sufficient performance to reach the airships' normal operating altitudes in time to catch them. Therefore, in September 1917, a 200hp Hispano-Suiza engine was fitted to a B.E.12, this machine being preferred by service pilots to its single-bay successor. A car-type radiator gave the new machine a nose profile similar to that of the S.E.5, and long exhaust pipes, terminating aft of the cockpit, were fitted. It is possible that the installation was made by the Southern Aircraft Repair Depot, which shared the Farnborough site, but, whatever the case, the designers of the Royal Aircraft Factory were closely involved.
The new machine, designated B.E. 12b, was found to possess a rate of climb so much improved that, despite the (ever-pressing) shortage of Hispano-Suiza engines or the licence-built variants, 100 examples were ordered to be built by Daimler.
The B.E.12b was normally armed with a single Lewis gun on an overwing mounting, firing over the propeller disc, the wing shielding the pilot's eyes from the muzzle flash. Some examples sported twin guns, similarly positioned. A ring-and-bead sight was provided, fixed to the starboard centre-section struts. In view of their intended role as night fighters, B.E.12bs were provided with navigation lights and Holt flare brackets under their lower wingtips to facilitate landing. Some machines had exhaust pipes with their ends flared out to act as flame dampers. The normal B.E.12 fuel tank was retained but, as this was shaped to continue the slope of the air scoop needed with the R.A.F.4a engine, it was turned around so that it sloped upwards to the rear, thus reducing its resistance.
As the Zeppelin attacks had virtually stopped before many B.E.12bs could be built, few ever saw service. It is possible that many airframes never actually received Hispano-Suiza-type engines and may have been completed as standard B.E. 12s powered by R.A.F.4as.
Powerplant: 200hp Hispano-Suiza V-8
Dimensions: As B.E.12a.
F.Manson British Bomber Since 1914 (Putnam)
Royal Aircraft Factory B.E.12
The growing clamour during the latter half of 1915 over the inferior aircraft being supplied to the RFC in France was focused principally on the Factory's B.E.2C, an aeroplane that had been applauded early in its Service life on account of its inherent stability in all three axes a laudable quality for unopposed reconnaissance work but suicidal in the presence of enemy fighters. It was slow and simply incapable of evasive manoeuvre and, when required to carry bombs, suffered enormous losses. Nor was the B.E.8's performance significantly better.
For months the Army remained deaf to calls for an enquiry into the administration of the Factory and the reasoning behind the continued letting of contracts for B.E.2 production. Moreover, during the early months of 1916, as a result of further Parliamentary charges by Noel Pemberton Billing, the Burbidge Committee's report was published, only to demonstrate steadfast support for the B.E.2C as an effective operational aeroplane. None of the report's authors was a close witness to events over the Western Front.
Discomfited by further charges in Parliament, the War Office halted production of the B.E.2C in mid-1916, although the aircraft continued in service for a further year. It had, however, been divulged that the Factory had already, in mid-1915, initiated action to further develop the B.E.2/B.E.8 formula, and a marginally improved aircraft, the B.E.12, was first flown in August that year.
Nevertheless, it was the War Office's clear intention to introduce a fighter aircraft into service (the Airco D.H.2), capable of meeting the German fighting scouts on equal terms, rather than to pursue fundamental changes in existing bombing and reconnaissance aircraft, believing that providing escorts for the established B.E.s would halt the rising losses being suffered.
Little urgency was therefore lent to the B.E.12's development. The prototype was a converted B.E.2C, No 1697, in which the front cockpit was deleted and a 140hp R.A.F.4A twelve-cylinder air-cooled in-line engine replaced the 90hp R.A.F. 1 A. No gun armament was provided initially (confirming that the new aircraft was conceived as yet another bomber/reconnaissance type, for which fighter escort would be available).
While No 1697 went to France during the autumn of 1915 for Service trials, production orders were placed with three Coventry-based manufacturers, Daimler also being contracted to produce the Factory's R.A.F.4A engine. Delays with the latter prevented completion of the first production B.E.12s until March 1916, and it was midsummer before examples were reaching the Squadrons in France, by which time the superior German scouts had been demonstrating their ability to evade the RFC's escorts to attack the reconnaissance machines.
As a result, the B.E.12s were provided with a single fixed, forward-firing Vickers gun on the side of the fuselage, but this was found to be virtually useless as the B.E. still lacked the manoeuvrability to engage in any sort of dogfighting. By adopting the smaller tailplane of the B.E.2E, some improvement in handling was evident, but when a Lewis gun was also provided on a pillar mounting behind the pilot's left shoulder, the aircraft proved almost unmanageable and the gun incapable o f being aimed. In August 1916, therefore, the aircraft was withdrawn from daylight reconnaissance duties and transferred almost exclusively to night bombing, a task which it continued to perform until February 1917.
In mid-1916 an attempt was made to improve the B.E.12's manoeuvrability by adopting the B.E.2E's single-bay wings of unequal span, this version - the B.E.12A arriving on the Squadrons at the end of the year, but with little real evidence of improvement. (The B.E.12B, of late 1917, was an anti-Zeppelin fighter, powered by a 200hp Hispano-Suiza engine, and therefore lies outside the scope of this work.)
A few B.E. 12s served with No 17 Squadron at Mikra Bay, near Salonika, from November 1916, being flown as fighters, bombers and reconnaissance aircraft, as opportunity dictated; and it was this Squadron's well-known pilot, Capt Gilbert Ware Murlis-Green (later Gp Capt, DSO, MC, RAF) who achieved the rare score of three enemy aircraft shot down while flying the B.E.12.
These operations only served to extend the original B.E.'s dismal service and anachronistic operational role. That B.E.s continued to be manufactured and flown on operations long after they had been shown to be disastrously outdated emphasised the War Office's wholly unjustified dependence on the products of the Royal Aircraft Factory.
Type: Single-engine, single-seat, two-bay biplane light reconnaissance/bomber.
Manufacturers: The Daimler Co Ltd, Coventry; The Standard Motor Co Ltd, Coventry; The Coventry Ordnance Works Ltd, Coventry.
Powerplant: One 140hp R.A.F.4A in-line engine driving four-blade propeller.
Dimensions: Span, 37ft 0in; length, 27ft 3in; height, 11ft 1 1/2in; wing area, 371 sq ft.
Weights: Tare, 1,635 lb; all-up, 2,352 lb.
Performance: Max speed, 102 mph at sea level, 91 mph at 10,000ft; climb to 10,000ft, 33 min; service ceiling, 12,500ft; endurance, 3 hr.
Armament: Gun armament comprised one 0 303in Vickers machine gun on nose with Vickers mechanical interrupter gear, and occasionally one Lewis gun on pillar mounting aft of the cockpit on the port side; bomb load of up to two 112 lb, four 65 lb, sixteen 16 lb or eight 20 lb or 25 lb bombs carried under the wings.
Prototype: No 1697 (a converted Bristol-built B.E.2C), first flown at Farnborough by Frank Goodden in August 1915.
Production: A total of about 400 B.E.12s was built but, bv the time the aircraft began bombing operations, many had been lost in action while flown as fighting scouts. The following are known to have been built: Nos 6136-6185 (Standard Motors, 50, all built as B.E.12s); Nos 6478-6677 (Daimler, 200, all built as B.E.12s); A562-A611 (Coventry Ordnance, 50; six completed as B.E.12As); A4006-A4055 (Daimler, 50; three completed as B.E.12As); A6301-A6350 (Daimler, 50; three completed as B.E.12As); C3081-C3280 (Daimler, 200; mixed B.E.12s, B.E.12As and B.E.12Bs).
Summary of Service: B.E. 12s served with Nos 10, 19 and 21 Squadrons on light bombing duties over the Western Front, and No 17 Squadron at Salonika.
H.King Armament of British Aircraft (Putnam)
B.E.12. The earliest recorded armament tests with a B.E.12 involved the dropping of bombs and darts (Farnborough, September 1915). By March 1916 an experimental gun-mounting of indeterminate type had been installed, and in June of the same year one machine was tested with a Lewis gun and deflector plates on the airscrew. A fixed Lewis gun on the starboard side, firing through the disc swept by an airscrew having deflector plates, was to be numbered among standard installations, and Oliver Stewart records 'one or two Lewis guns mounted to clear the disc swept by the airscrew'. He comments: 'There were brackets alongside the pilot, and the guns fixed to these brackets were splayed outwards. Control of the guns was either directly by hand or by means of Bowden cables.' Not surprisingly, the complicated problems of deflection involved in the 'crab' method of attack necessitated gave poor results. In May 1916 the Central Flying School tested a B.E.12 having a fixed Vickers gun with Vickers synchronising gear, and this was to become another standard installation, together with a Lewis gun on a Strange mounting, as illustrated. Sometimes there were two Lewis guns on Strange mountings. A Lewis gun actuated by the Vickers gear is also on record. For Home Defence work the Vickers gun was fed with ordinary ball ammunition, with one round of Sparklet in five, whereas the Lewis gun fired explosive/incendiary ammunition. Some Home Defence B.E.12s had as many as four Lewis guns, and Le Prieur rockets were also fitted. Probably the most spectacular installation was that involving a six-pdr Davis recoilless gun. This gun fired upwards at 45 degrees; the muzzle was at the level of the upper wing, which was cut away accordingly as far as the front spar. For reloading the gun was lowered to the horizontal.
Bomb loads were one or two 112-lb or up to sixteen 20-lb.
B.E.12a. When used as a bomber (typically with one 112-lb bomb under the fuselage) this aircraft sometimes had a Lewis gun on a Strange mounting ahead of the cockpit. There was also an installation of a fixed Vickers gun.
B.E.12b. Although it could carry two 112-lb bombs under the lower inner wings, this single-seater was introduced in 1917 primarily for Home Defence. The armament for this duty was one or two Lewis guns, mounted over the centre-section and firing special ammunition above the airscrew arc. The Neame illuminated sight was fitted (on the starboard gun when a pair was mounted). Additionally there was a ring-and-bead sight, the two elements of which were attached to the starboard centre-section struts. The mounting for the gun(s) was one of the most elaborate of the war. Running between the rear centre-section struts was a cross-bar, and pivoted to this was a steel-tube assembly which constituted the mounting proper. A cable running over a pulley at the top of the front forward centre-section strut connected the mounting to a large lever attached outside the cockpit on the starboard side, somewhat reminiscent of the multipurpose lever in the Blackburn Blackburd. With the lever pulled to the rear the gun(s) were in a position to fire forwards above the airscrew; when the lever was moved forward the gun(s) were moved into a vertical position for reloading or upward firing.
P.Lewis The British Fighter since 1912 (Putnam)
While the F.E.2b and F.E.2d were thus playing their part in the air war, another Royal Aircraft Factory design, the B.E.2c, was modified as a singleseat fighter in response to pressing demands from the Royal Flying Corps for such a type. Rather than set about designing a completely fresh machine, the Factory decided that the most expeditious way of meeting the case would be to modify the B.E.2c as dictated by the requirements.
Airframe 1697 was selected for conversion into the prototype B.E.12, the designation allotted to the project. A new engine, the 150 h.p. R.A.F.4a, was installed in the nose and the front cockpit was deleted. Production B.E.12s embodied several detail modifications to provide increased fuel capacity and improved performance. Normal armament applied to the B.E.12 consisted of a single Vickers gun mounted to port on the fuselage and equipped with Vickers interrupter gear. Occasionally, additional fire-power was provided by a Lewis gun installed to starboard on a Strange mounting and alternative armament fitted consisted of a pair of fuselage Lewis guns on Strange mountings.
The B.E.12 arrived in France to do battle in mid-Summer of 1916 but, in producing the conversion, the fundamental fact had been overlooked that inherent stability was a highly-developed feature of the B.E.2c but was not a quality which was in the least compatible with a fighter’s primary and essential requirement of manoeuvrability. The extra power and armament did nothing to meet this need and the B.E.12 was patently unable to rise to the requirements for which, in good faith, it had been designed. After but a few months’ use as a fighter, the B.E.12 was relegated to duties as a single-seat bomber.
And yet, a further attempt was made to turn the B.E.12 into a successful fighter by producing a new version with single-bay wings. This was the B.E.12a which had the same 150 h.p. R.A.F.4a engine but was fitted with greatly extended tips to the upper wings. These tips terminated in ailerons given exaggerated horn balances which reached forward to the leading edge. The design proved unsatisfactory and was modified to use normal B.E.2e wings with strut-connected ailerons on each tip. At first this revised type was known as the B.E.12Ae but soon reverted in nomenclature to B.E.12a. All of this endeavour was in vain as the B.E.12a was as much a failure as the B.E.12 and served only in small numbers.
An addition to the Home Defence fighter force during 1917 was a more powerful version of the B.E.12 with the 200 h.p. Hispano-Suiza engine and designated B.E.12b. A pair of Lewis guns on the upper centre-section armed the machine, thirty-six of which operated with Home Defence units.
F.Mason The British Fighter since 1912 (Putnam)
It is believed that the Royal Aircraft Factory’s B.E.12 was first flown at about the same time as the Sopwith Pup. No two fighters, conceived to counter the same threat, can have been more different, yet well illustrate the different approaches to the supply of military aircraft by Government and commercial industry. Whereas the Sopwith Pup was an inspired design born of independent thought, the B.E.12 was evolved, for reasons of expediency, from an existing design of barely adequate mediocrity.
To meet urgent demands from the RFC in France for a single-seat fighter to meet the threat posed by the new German scouts, the Royal Aircraft Factory simply adapted the B.E.2C, producing a prototype by modifying a Bristol-built aircraft (No 1697) by installing a 150hp RAF 4A engine, changing to single-bay wings and deleting the front cockpit. Sub-contracted production was put in hand at the Coventry Ordnance Works, Daimler and Standard Motors, all in Coventry.
By the beginning of July 1916 a single B.E.12 had been delivered to No 10 Squadron at Chocques in France, and the first Squadron, fully equipped with the aircraft, was No 19 which arrived at Fienvilliers on 1 August under the command of Maj R M Rodwell. No 21 Squadron re-equipped with B.E.12s later the same month. It soon became apparent that by simply increasing the engine power and adopting single-bay wings did not transform the B.E.2C into an effective fighter, and in the following month it was - at the insistence of General Trenchard himself - withdrawn from the fighter role in France and transferred to bombing. Losses had become prohibitive.
Meanwhile the Factory had attempted to improve the B.E.12’s manoeuvrability by fitting a top wing similar to that of the B.E.2E, but adding extended ailerons on the top wing only, with enormous horn balances. This aircraft, No 6511, was termed the B.E.12A, but after trouble was experienced during flight tests, the aircraft reverted to standard ailerons on upper and lower wings; the aircraft’s designation was temporarily changed to B.E.12Ae, but soon reverted to B.E.12A. Needless to say, after the previous experiences, B.E.12As were not issued to RFC squadrons in France, although a small number was sent to Palestine in 1917 for use by No 67 (Australian) Squadron until early the following year.
Both B.E. 12s and 12As were issued to Home Defence squadrons at the end of 1916, and on the night of 16/17 June 1917 Lieut L P Watkins of No 37 Squadron, flying B.E.12 No 6610, shot down Zeppelin L48 from 14,000 feet over Theberton, Suffolk.
The B.E.12B was a version specially developed in 1917 as a night fighter and was powered by a 200hp Hispano-Suiza engine. Its armament comprised a pair of Lewis guns side-by-side on a special mounting above the upper wing centresection; the starboard gun was fitted with a Hutton illuminated sight and, for firing directly ahead (over the propeller), a plain ring and bead sight was attached to the starboard cabane struts. For upward firing and changing the ammunition drums, the guns pivoted downwards so as to be within reach of the cockpit. The engine and exhaust system were similar to those on the S.E.5A - by then being developed by the Factory.
A total of thirty-six B.E.12Bs was issued to Home Defence Squadrons.
Type: Single-engine, single-seat, single-bay biplane scout.
Manufacturers: The Royal Aircraft Factory, Farnborough, Hants; The Coventry Ordnance Works Ltd, Coventry; The Daimler Co Ltd, Coventry; The Standard Motor Co Ltd, Coventry.
Powerplant: B.E.12 and 12A. One 150hp RAF 4A engine. B.E.12B. 200hp Hispano-Suiza.
Structure: Wooden construction with fabric covering; plain V-strut, twin-wheel undercarriage without skids.
Dimensions: Span (B.E.12 and 12B), 37ft 0in; length, 27ft 3in; height (B.E.12), 11ft 1 1/2 in; wing area, 371 sq ft.
Weights: (B.E.12A) Tare, 1,610 lb; all-up, 2,327lb.
Performance: B.E.12A. Max speed, 100 mph at sea level; climb to 10,000ft, 24 min 15 sec; service ceiling, approx 12,000ft.
Armament: B.E.12. Either one synchronized 0.303in Vickers machine gun or one fixed Lewis gun on each side of the fuselage on Strange mountings. B.E.12B. Twin Lewis guns mounted on upper wing centre section to fire above the propeller arc.
Prototypes: One B.E.12 prototype, No 1697, modified (probably first flown in February 1916). One B.E.12A prototype, No 6511.
Production: 600, according to known serial numbers. (50 by Standard, Nos 6136-6185; 50 by Coventry Ordnance, A562-A611; and 500 by Daimler, Nos 6478-6677, A4006-A4055, A6301-A6350 and C3081-C3280).
Summary of Service: B.E.12s served with Nos 10, 19 and 21 Squadrons, RFC, in France; Nos 17, 47 and 150 Squadrons, RFC, in Macedonia; Nos 36, 37, 50, 51, 76 and 76 (Home Defence) Squadrons, RFC. B.E.12As served with No 67 (Australian) Squadron in Palestine, and Nos 50, 76 and 112 (Home Defence) Squadrons, RFC. B.E.12Bs served with Nos 50, 51, 76 and 77 (Home Defence) Squadrons, RFC.
W.Green, G.Swanborough The Complete Book of Fighters
ROYAL AIRCRAFT FACTORY B.E.12 UK
Evolved at Farnborough during 1915 as a marriage of the B.E.2c airframe with the then-new R.A.F.4 air-cooled 12-cylinder Vee-type engine of 140 hp, the B.E.12 prototype began test flying at the end of July that year. Although flown from the start as a single-seater, it was at first unarmed and was intended for such roles as bombing and photography rather than as a fighter. The prototype was tested in France in September 1915 and its generally satisfactory performance encouraged the War Office to order production of the B.E.12 in that same month. Delivered from March 1916 onwards, production aircraft had the R.A.F.4a engine (with increased stroke), twin upright exhaust stacks, an auxiliary gravity fuel tank under the port upper wing and, after the first few, an enlarged rudder with curved leading edge. At first serving with RFC squadrons in France for general duties, the B.E.12 was fitted with a 0.303-in (7,7-mm) Lewis machine gun on an oblique mounting on the fuselage side, or over the wing centre section, but several other experimental installations were tried at Farnborough before the decision to adopt the newly-available Vickers-Challenger interrupter gear, using a Vickers gun firing through the propeller disc. Difficulties with the gear, combined with the excessive stability of the B.E.12 (to overcome which the B.E.2e-type tailplane and elevators were used on some B.E.12s), made the type ineffectual as a fighter, however, and it was soon withdrawn from France, having served with only two squadrons. B.E.12s remained in service with Home Defence squadrons through 1917, many alternative armament installations being tried, including a quartet of Lewis guns, and sets of Le Prieur rockets on the interplane struts. One Zeppelin was shot down by a B.E.12, in June 1917. At Farnborough, one was tested with a Davis six-pounder recoilless gun, firing upwards at 45 deg for anti-Zeppelin use, but this was not adopted for production. Contracts were placed with two companies for B.E.12 production, Daimler building 200 and Standard Motor Co, 50, against the original orders placed in 1915, and Daimler receiving a contract for 200 more in August 1917. Many of the latter, however, were completed as B.E.12b's (which see).
Max speed, 102 mph (164 km/h) at sea level, 91 mph (146 km/h) at 10,000 ft (3 050 m).
Time to 10,000 ft (3050 m), 33 min.
Service ceiling, 12,500 ft (3810 m).
Endurance, 3 hrs.
Empty weight, 1,635 lb (742 kg).
Loaded weight, 2,352 lb (1067 kg).
Span, 37ft 0 in (11,3 m).
Length, 27 ft 3 in (8,31 m).
Height, 11 ft 1 1/2 in (3,39 m).
Wing area, 371 sq ft (34,47 m2).
ROYAL AIRCRAFT FACTORY B.E.12A UK
With the B.E.12 established in production in 1916, based on the B.E.2c airframe with its equi-span two-bay wing and massive horizontal tail surfaces, a further marriage was arranged to combine the R.A.F.4a engine with the newer B.E.2e airframe. This introduced the single-bay cellule with overhanging upper wing and a smaller tailplane/elevator combination, together with the larger, rounded fin of the B.E.12. Designated B.E.12a in this form, the type was ordered from Coventry Ordnance Works and Daimler, each of which received contracts for 50 during 1916 (some of the Daimler batch being completed as B.E.12s). The B.E.12a’s served briefly with Home Defence units and more extensively in Palestine, with the Australian-manned No 67 Squadron.
Max speed, 105 mph (169 km/h) at sea level, 80.5 mph (129.5 km/h) at 10,000 ft (3 050 m).
Time to 10,0 ft (3 050 m), 24.25 min.
Empty weight, 1,610 lb (730 kg).
Loaded weight, 2,327 lb (1056 kg).
Span, 40 ft 0 in (12,19 m).
Length, 27 ft 3 in (8,30 m).
Height, 12 ft 0 in (3,66 m).
Wing area, 360 sq ft (33,44 m2).
ROYAL AIRCRAFT FACTORY B.E.12B UK
In an attempt to improve the performance of the B.E.12, primarily for the benefit of Home Defence squadrons, a 200 hp Hispano-Suiza water-cooled eight-cylinder Vee-type engine was substituted for the 150 hp R.A.F.4a. The first such installation was completed in September 1917 by the Southern Aircraft Repair Depot at Farnborough and demonstrated a dramatic improvement in speed and climb performance. Consequently, it was decided that 150 of the 200 B.E.12s ordered from Daimler in August 1917 should be completed with the Hispano engines as B.E.12b’s. Airframes built by Daimler were fitted with these engines at the Northern Aircraft Repair Depot at Aston, near Sheffield, and deliveries began late in 1917. As Zeppelin raids on the UK had by this time virtually come to an end, many B.E.12b’s went straight into store, their urgently-needed engines being removed for use in other aircraft types, such as the S.E.5a. It is believed that production of B.E.12b’s ended some 12-20 short of the intended total. The standard armament of the B.E.12b comprised a 0.303-in (7,7-mm) Lewis gun above the centre section, firing over the propeller disc. Performance and weight data for the B.E.12b are not recorded. Dimensions similar to those of the B.E.12.