O.Thetford, P.Gray German Aircraft of the First World War (Putnam)

Brandenburg W 12

   Work was begun on the Brandenburg W 12 in the autumn of 1916, in response to a request from the seaplane stations for a defence fighter equipped with a machine-gun to fire rearwards. Although the single-seat defence fighters (Albatros W 4, Brandenburg K.D.W., etc.) had proved a useful weapon to the naval service, they were completely defenceless against attack from the rear, and a solution to this vulnerability was sought in the design of the W 12. The elevated siting of the rear gun mounting gave an excellent all-round field of fire, including forward over the top wing. In addition, the aircraft itself was technically first class, for in spite of its weight and size, it was in no way inferior to the single-seaters in speed and manoeuvrability. The single-bay wings and absence of interplane bracing cables were a unique feature on a two-seater seaplane, and undoubtedly contributed to the excellent performance.
   In January 1917 the prototype was completed at Briest works, but due to the water on the Havel River being frozen, it was shipped to the seaplane test establishment at Warnemunde. The initial test flight was a somewhat hectic affair in which the aircraft proved excessively tail heavy; however, a safe landing was contrived, and overnight modification of the wing structure corrected the centre of gravity and rectified this disconcerting trait. Although this prototype was later written off in an unlucky landing in breakers, the results thus far achieved, both in performance and general flying qualities, inspired sufficient confidence for a first series order to be placed.
   The designer of the W 12 was Ernst Heinkel, who had fathered earlier successful designs from the Hansa Brandenburg works and who, a couple of decades later, was to produce the famous bombers from his own factories. As subsequent batches of W 12s were produced, so they differed slightly in detail, as seems to be inevitably the case with the majority of German naval aircraft types. However, the basic airframe remained substantially the same.
   The fuselage was based on four main spruce longerons and spacers, with robust multi-ply formers forward of the cockpit supporting the engine bearers. The power-plant was either a 160 h.p. Mercedes D III or a 150 h.p. Benz Bz III according to series batch. Those with Mercedes motors were fitted with leading-edge-mounted radiators while W 12s with the Benz installation had a car-type radiator at the extreme nose. Immediately of the engine bearers, the longerons raked upwards towards the tail to give the elevated position for the gun mounting, which bestowed the improved field of fire. The slab sides tapered to a vertical knife-edge aft, with little or no taper in elevation, resulting in an extremely deep section at the tail end. This additional side area compensated for the float area and lack of vertical fin. The fuselage was plywood covered, and windows were provided in the floors of the cockpits to give improved downward visibility. The wooden cantilever tailplane was much thicker in section at the centre, and because of the resultant increase in airflow disturbance, the steel-tube-framed elevators had to be re-designed with a considerable degree of inverse taper to improve effectiveness. Mounted on top of the fuselage, the tailplane was well clear of the spray when taxi-ing, and the absence of bracing struts enabled the gunner to fire under the tail quite close in to the fuselage. The fabric-covered steel-tube rudder was attached to the fuselage sternpost, the balance portion extending below the fuselage to leave the area above the tailplane unrestricted for firing.
   The wing structure was made compact and additionally strong in order to dispense with interplane bracing cables, enabling the gunner to fire through the wings. Construction was orthodox, although a deep aerofoil section was employed to provide the required strength factor. Plywood ribs, flanged with soft timber, were closely spaced on the two spruce main pars; both wings were of constant chord and, after the first batch of six aircraft, had rounded tips. The upper wing was a one-piece structure scured to the centre-section struts; the cut-out was shallow in the first batch, but the reduction of stagger in later series necessitated a much deeper cut-out. Ailerons of welded steel-tube framing were fitted, and control cables were designed to provide independent operation should any combat damage occur. Later batches of aircraft were fitted with four ailerons, connected with a link strut, and the ample aileron area contributed to the W 12's outstanding manoeuvrability.
   The floats were supported on a chassis of steel-tube struts, faired with plywood and attached with ball joints. Additional "N" struts braced the floats to the wings at the junction of the interplane struts, lending additional rigidity to the wing cellule. The floats themselves were of wood; a basic framework of formers and stringers being covered with high-grade maritime three-ply.
   On entering service with the seaplane stations, the Brandenburg W 12 soon proved itself an excellent weapon against the Allied seaplanes. Particularly pleased to receive the W 12 were the pilots at Zeebrugge, who had suffered at the hands of the large, well-armed, British flying-boats in the North Sea. Oberleutnant Christiansen soon distinguished himself as a capable exponent of the W 12, and probably his most spectacular victory was the shooting down in flames of the British non-rigid airship C 27 on 17th December 1917. A colleague of Christiansen's at this time was a midshipman, von Wyk, who between the wars became famous as the pilot of the giant twelve-engined Dornier Do X.
   W 12s were also operated on reconnaissance, often venturing to British coastal waters. When used on such duties one of the forward-firing guns was dispensed with and radio apparatus carried in its stead.

TECHNICAL DATA
   Description: Two-seat fighter seaplane.
   Manufacturer: Hansa und Brandenburgische Flugzeug-Werke G.m.b.H.
   Power Plant:
   One 160 h.p. Mercedes D III 6 cylinder in-line water-cooled engine.
   One 150 h.p. Benz Bz III 6 cylinder in-line water-cooled engine.
   Dimensions: Span, 112m. (36 ft. 9 in.). Length, 9 6 m. (31 ft. 6 in.). Height, 3.3 m. (10 ft. 10 in.). Area, 35.3 sq.m. (381.25 sq.ft.).
   Weights: Empty, 997 kg. (2,193.4 lb.). Loaded, 1,454 kg. (3,198.8 lb.).
   Performance: Maximum speed, 159.5 km.hr. (100 m.p.h.). Climb, 1,000 m. (3,280 ft.) in 7 min.; 2,000 m. (6,560 ft.) in 18-9 min. Ceiling, 16,400 ft. Endurance, 3 1/2 hrs.
   Armament: One or two fixed Spandau machine-guns and one manually operated Parabellum in rear cockpit.
   Serial Numbers: One aircraft, Marine No. 2016, was experimentally fitted with vee-eight-type motor, probably 195 h.p. Benz Bz IIIb. 146 aircraft supplied,
   Marine numbers:
   1011-1016, 160 h.p. Mercedes, two machine-guns.
   1178 1187, 150 h.p. Benz, two machine-guns.
   1395-1414, 150 h.p. Benz, two machine-guns.
   2000-2019, 150 h.p. Benz, two machine-guns (except 2016 above).
   2023-2052, 150 h.p. Benz, three machine-guns.
   2093-2132, 160 h.p. Mercedes, two machine-guns.
   2217-2236, 160 h.p. Mercedes, two machine-guns, also radio fitted.

W.Green, G.Swanborough The Complete Book of Fighters

BRANDENBURG W 12 Germany

   A single-bay twin-float two-seat fighter biplane, the W 12 was flown for the first time in January 1917 with a 160 hp Mercedes D III six-cylinder water-cooled engine. Of wooden construction with plywood fuselage skinning, the W12 was produced for the German Navy with both the 160 hp Mercedes D IIIa engine and the 150 hp Benz Bz III, and proved outstandingly manoeuvrable. Its first operations were conducted from the seaplane station at Zeebrugge, from where it quickly distinguished itself in service. Standard armament comprised one forward-firing synchronised 7,92-mm LMG 08/15 machine gun and a Parabellum of similar calibre on a flexible mount in the rear cockpit, but of the 146 W 12s that had been built when production terminated in June 1918, one batch of 30 Benz-engined fighters had been delivered with a forward-firing armament of two LMGs.

Max speed, 99 mph (160 km/h).
Time to 3,280 ft (1000 m), 7.0 min, to 6,560 ft (2 000 m), 18.9 min.
Endurance, 3.5 hrs.
Empty weight, 2,198 lb (997 kg).
Loaded weight, 3,205 lb (1454 kg).
Span, 36 ft 8 7/8 in (11,2 m).
Length, 31 ft 6 in (9,60 m).
Height, 10 ft 10 in (3,30 in).
Wing area, 389.66 sq ft (36,2 m2).

J.Herris German Seaplane Fighters of WWI (A Centennial Perspective on Great War Airplanes 2)

Brandenburg W12

   The Brandenburg W12 two-seat floatplane fighter was a breakthrough design. Despite being a two-seater using the same engines powering the smaller single-seaters it replaced, it had similar speed and greater range coupled with better maneuverability and flying characteristics!
   Its two-seat configuration also provided greatly improved air-to-air combat effectiveness from its combination of fixed and flexible armament, and the second crewman was able to assist the pilot with over-water navigation, a particular operational challenge in the days before electronic navigation aids. Furthermore, some W 12s carried wireless senders and receivers for the observer, something none of the single-seat fighters could do that was a tactical advantage. The W12 made all preceding single-seat seaplane fighters obsolete at a stroke.
   The key secret of its success was its innovative structural design that used its sturdy float bracing to also support the wings, eliminating the need for separate, drag-producing bracing wires, a key to its good speed. Furthermore, its innovative tail design gave the observer excellent visibility and field of fire. In addition, the observer and his gun ring were mounted high enough that he could fire forward over the upper wing, giving him an unexcelled field of fire and further enhancing combat effectiveness.
   Despite its general excellence, the basic design was subject to a great deal of fine tuning to improve stability, maneuverability, and sea handling. In fact, none of the Brandenburg two-seat fighters were ever able to handle sea states as rough as the robust Friedrichshafen reconnaissance floatplanes, and there were continual problems with float maintenance. Fuselage length was extended in later aircraft to improve longitudinal stability, and late production aircraft had ailerons on all four wings for improved maneuverability. The center section was also redesigned during production to improve the pilot's field of view and ease of egress in emergencies. Some 30 later aircraft were fitted with two fixed guns for the pilot, and some aircraft with only a single gun for the pilot were fitted with wireless.


Brandenburg W12 Production Orders
Order Date Marine Numbers Qty Class Engine Notes
15 Oct. 1916 1014-1016 3 C2MG Mercedes D.III 1014 was prototype, short fuselage
22 Nov. 1916 1011-1013 3 C2MG Mercedes D.III Short fuselage
5 Jan. 1917 1178-1187 10 C2MG Benz Bz.III 1185 had longer fuselage
13 Mar. 1917 1395-1414 20 C2MG Benz Bz.III Short fuselages; 1413 had four ailerons
10 Sep.1917 2000-2019 20 C2MG Benz Bz.III Long fuselages start with this series. Larger wing cut-out.
Oct. 1917 2023-2052 30 C3MG Benz Bz.IH Two fixed machine guns. 2027 destroyed during acceptance testing.
Oct. 1917 2093-2112 20 C2MG Mercedes D.III -
Oct. 1917 2113-2132 20 C3MG Mercedes D.III Two fixed machine guns
Nov. 1917 2217-2236 20 C2MGHFT Mercedes D.IIIa Wireless equipment fitted

Note: Of 146 W12 aircraft built, 116 aircraft had one fixed gun; 30 aircraft had two fixed guns.

C.Owers Hansa-Brandenburg Aircraft of WWI Vol.2: Biplane Seaplanes (A Centennial Perspective on Great War Airplanes 18)

Type W.12
  
   The KDW and Albatros W.4 single-seater fighters performed well for their day, but were obsolescent by the end of 1916 and the Naval authorities had already determined to concentrate their limited raw materials to the development of two-seat fighter floatplanes that would be defended from the rear. The English were experimenting with the Curtiss America flying boats and the first Large America boat, the Curtiss H-8 serial 8650, arrived at Felixstowe for erection on 24 March 1916. The machine required much modification and the improved type, designated H-12, started to enter service at the end of the year, therefore the W.12 was not designed to counteract the Large America flying boats as has been suggested in some publications. The British Short floatplanes on anti-submarine patrols from Dunkirk were escorted by Sopwith Baby fighters. By May 1917 the Dunkirk seaplanes were unable to undertake meaningful work due to the opposition by German fighting aircraft, and it was suggested that the Baby seaplanes be replaced by fighter land planes.
   A combat on 19 June 1917, with Short 184 serial 9057 and its two escorting Sopwith Baby fighters of the Dunkirk Seaplane Squadron, emphasized the change in conditions. The British aircraft set out on a mine and U-Boat spotting patrol. When half an hour out and about 12 miles north-east of Dunkirk they were attacked by three enemy fighting seaplanes. Flt. Sub. Lt. J.E. Potvin in Baby N1015 was shot down by the German pilot Dyck, who was himself brought down with an abdomen wound when attacked by Flt. Lt. R. Graham in the other Baby. In the meantime the observer in the Short, Lt. T. Rogers, had been shot and killed by another of the attacking Germans. The Short's radiator and fuel tank had been hit, forcing the floatplane to alight. Graham's Baby was badly shot about and he was forced to leave the action with a failing engine. He alighted alongside a French destroyer and sent two messages by pigeon to Dunkirk. Graham wrote that the Short had been shot down and "Potvin?" His tank had been shot and he couldn't climb. He requested that more fighters be sent.
   Dyck had managed to alight safely and one of his companions landed alongside and removed the wounded pilot to his own single-seat fighter and succeeded in reaching Ostend, but in vain, as Dyck had died on the way. A thunderstorm meant that Dunkirk could not send out any aircraft and the decision was made to send out two of the then secret Coastal Motor Boats (CMB) as speed was essential. One of the boats suffered engine problems and was captured by the Germans. The other had an eventful cruise, being attacked by four enemy destroyers, and after firing a torpedo, unsuccessfully, returned without seeing anything. It was afterwards learned that German destroyers had reached the Short and taken aboard her pilot and dead observer. This episode resulted in the loss of two seaplanes and one of the new CMB vessels, and emphasized the need for first-class fighter aircraft to oppose the German seaplanes. The Baby seaplanes were replaced by Sopwith Pup fighters and later by Sopwith Camels when the Flight was expanded into the Seaplane Defence Squadron (later No.13 Squadron, RNAS).
   The first Brandenburg floatplane fighter to achieve fame, the W.12 exhibited characteristics that the late P.M. Grosz noted were inherited from the development of the Brandenburg Type K and KDD landplanes built for the Austro-Hungarian LFT. These characteristics were the high-sided fuselage with rudder under the tailplane giving the rear gunner an unparallel field of fire without danger of damaging his own aircraft. The Castiglioni group of companies shared information and it is probable that the fuselage design of the prototype that became the W.12 was influenced by the design efforts in Austro-Hungary that led to the Phonix and UFAG C.I reconnaissance two-seat biplanes.
   Heinkel states that he designed the W.12 in eight weeks. Heinkel was the Chief Designer but was not alone in working on the design. He states in his autobiography that he had to work hard to achieve the light, strong structure in order to meet the performance specification with the then available engines.
   The W.12 was designed in 1916 as a seaplane defence fighter having a gun for rearward protection. The German Navy placed an order for three W.12 prototypes on 15 October 1916, (MN 1014 - 1016). This was followed the next month by another order for three further prototypes (MN 1011 - 1013).(41)
   The W.12 was of conventional Brandenburg construction but possessed design characteristics that were to be carried forward through to the next models of Brandenburg fighters and to influence other manufacturers. The fuselage was based on four spruce longerons with multi-ply formers supporting the engine. The pilot was located behind the engine seated over the fuel tank. Immediately aft of the engine bearers the longerons swept up towards the tail giving an elevated gun position for the observer. The observer's cockpit was surmounted by a metal basin shaped structure containing the gun ring. This allowed plenty of room for handling the gun. He could fire his LMG 14/17 Parabellum machine gun over the wing and, if necessary, through the wings without concern that he would cut the bracing cables as the structure did not require any cables. The fuselage tapered to a vertical knife edge. The cantilever horizontal tailplane was ply covered and mounted flush with the upper longerons, well clear of spray. The tailplane was thicker at the centre and air flow disturbance caused the steel tube elevators to be redesigned. The cantilevered tailplane meant that the gunner could aim his gun close to the fuselage without tailplane bracing struts entering his field of fire. The elevators were welded metal framed steel tube with fabric covering as were the rudder and ailerons. The rudder was mounted on the stern post with the balance section underneath the fuselage. The deep fuselage compensated for the additional float area and lack of a fin. The fuselage was of usual Brandenburg construction and covered with ply eliminating the need for internal wire bracing. Easily detachable metal panels forward enclosed the engine. Those machines equipped with the 160-hp Mercedes D.III engine had a leading edge radiator whilst the batches equipped with the 150-hp Benz Bz.III had a radiator mounted in the nose.
   The wings were of conventional construction but were of a thick aerofoil section in order to be strong enough to eliminate the interplane bracing cables. Both wings were of the same chord, tapering towards the tips. The upper wing was slightly longer than the lower wing. The wings were constructed around two spars, the upper wing being in one piece. A cut-out in the trailing edge gave the observer clear upward vision although this had to be enlarged on production machines. Plain unbalanced ailerons were carried on the top wing only. Later machines had ailerons on all wings connected by a link strut.
   A compass of the liquid type with floating dial of about 110 mm diameter was mounted in the lower wing about 900 mm from the side of the fuselage. In some cases it was illuminated with a small electric bulb protected from the front, the wiring for which was carried out from the fuselage through the wing. An air speed indicator of the cup type was often mounted on an interplane strut.
   The single step floats were of wood being composed of five water tight compartments and covered with marine ply. Bituminous paint was often used as a finish to make them watertight. A chassis of steel tube struts, in the form of the letter "M" in front view, connected the floats to the fuselage, the points of the "M" being located at the roots of the wing spars. Additional struts brace the floats to the wings under the interplane struts completed the structure. These formed the letter "N" in side elevation. The struts were steel tubes faired with light veneer. The ends of the struts were fitted with a screw plug that would have been used to align the machines. These struts formed a strong, robust structure that helped support the wing cellule without having to resort to cable bracing. This system of support struts was to be carried through the W.19, W.29, W.33, W.34 and proposed W.37, and was seen on the Heinkel He.1 post-war floatplane.
   The W.12 was not an instant success. As the waters round Brandenburg were frozen, the machine was crated and shipped to the seaplane test unit at Warnemunde for its first flight. Heinkel records that the test pilot was named Walter Stagge. On its first flight the W.12 proved dangerously tail heavy, and the observer had to throw all ballast out in order to allow the machine to make a safe alighting. The floatplane had to be re-rigged before the Navy personnel were allowed to fly it.(42) MN 1014 had arrived at the SVK in January 1917 but was later wrecked in an emergency landing, having to be rebuilt and was returned to testing in June 1917. Initial testing was promising, the machine possessing a good turn of speed and manoeuvrability. Before the prototypes had flown an order had been placed for ten production W.12 fighters. These machines had round wingtips as against the prototypes square tips.
   As the W.12 was developed many improvements were tried and introduced into production batches. Later aircraft had four ailerons connected by a link strut that gave improved flight characteristics. A longer fuselage was introduced from MN 2000 that significantly improved longitudinal control and the rudder was reduced in area to compensate for the additional side area. Aerofoil radiators were tried as well as a narrow tailplane; there were at least three variations of the tailplane on production machines. The wings were basically the same on all batches.
   An early criticism was made to the location of the pilot under the upper wing. In the event of an accident, his chance of getting out was hampered by the interplane struts and wing. The cut-out was made larger on the first production batch, and increased later as a reduction in stagger moved the wing backwards. Redesigning the centre-section struts to facilitate entry/exit took longer. On early production machines the upper wing was supported by five struts, the odd leg carrying the fuel pipe to the upper wing gravity tank. Later machines had a revised system of two substantial support N struts.
   The modifications that were incorporated into production aircraft were faithfully recorded on the Atlas drawings of the various batches of the W.12 as reproduced in these pages.


W.12 in Service

   German Naval activities did not involve seeking out enemy seaplanes alone, in fact reconnaissance was more important. Dr. Fritz Stormer recalled that:
   Our submarines were particularly interested in changes of the buoys set out in our sector of the sea, as well as new blockade nettings, minefields, wrecks and other underwater obstacles, all of which we were supposed to report upon our return or landing at sea. Even if we could not convey the exact nautical position we could usually mention enough recognition points to make our report essentially clear, which was especially important when we pushed as far forward as High Margate in the Thames.
   The patrols would report whether the cleared channels for access for U-Boats were kept clear. As Dr Stormer noted:
   We did more than just interdict enemy aircraft. Indeed, our mission was mainly devoted to surveillance of maritime traffic in the entire blockade sector from the English coast to Holland. On many occasions, our aircraft pursued vessels and either dropped bombs near them or signalled them to halt by directing a stream of machine gun fire across their bows, after which a German boarding party would take over. In these instances the Staffeln reported the ship’s presence by wireless telegraphy and gave the precise location. Then a large seaplane would come out with a “prize officer” who was put aboard the captured vessel while our aircraft circled overhead and observed their slow progress towards our shore. Thus many large sailing ships, as well as two steamers, did not reach their intended ports of call and were, instead, brought into Zeebrugge. One of these prizes of war served as a barrack ship for the petty officers among our flying personnel.(43)
   In line with the above activities Christiansen's Staffel was credited with the destruction of the Dutch ship Agina on 12 July 1917.
   The W.12 entered active service in the autumn of 1916. By 12 February 1917, Zeebrugge had W.12 floatplanes MNs 1014 and 1015 in service. However it was not until October that the W.12 made its combat debut. A sortie by three Friedrichshafen FF 33L, an Albatros W.4 and Brandenburg W.12 MN 1183, left Zeebrugge at 1600 (German time). After one FF33L dropped out and alighted with engine trouble, and another returned to summons help to the downed biplane, the three remaining aircraft encountered a large British flying boat and attacked.
   This flying boat was Porte Baby 9810, a three-engined machine designed by John Porte at Felixstowe. The boat was on patrol from Felixstowe in the vicinity of the North Hinder Light Vessel when attacked by "an aeroplane and two fighting seaplanes." The pilot, Flt Cmdr N. Shoto Douglas, managed to avoid many of the attacks by sideslipping, until the port and centre engine were shot up and the boat forced to alight. Once on the water the Germans attacked but AM C. Spikings kept up return fire although he had been scalded when the engine near him had been set on fire. He also worked on the engines during the night despite having burned his hands. The boat managed to taxi to the Sizewell Gap, north of Oxford, where she was taken in tow.(44) The Baby was ill designed to withstand attacks by fighter aircraft. As a result of this action the Baby was not used where enemy aircraft were expected unless an escort of America flying boats could be given.
   The Germans claimed that the British flying boat was shot down with bullets in its left engine and radiator by the W.12. The pilot, Oberleutnant zur See Friedrich Christiansen, claiming his second victory.(45) This was to be the start of the increasing activities of the Zeebrugge Brandenburg biplanes and then monoplanes against the British patrolling flying boats that lasted until the end of the war.
   "Fiede" Christiansen's name now became synonymous with the activities of the Brandenburgs from Zeebrugge. The most spectacular victory achieved by Christiansen was the shooting down the British coastal non-rigid Astra-Torres type airship C27 on 11 December 1917, off the East Anglia coast. Three aircraft took off for an offensive patrol at 0900 (German time) and over the Outer Gabbard sighted a British airship in the vicinity of the North Hinder Lightship. MN 1183 began the fight and within two minutes the airship fell some 400 metres to the sea. The crew of five perished. In actuality Christiansen was responsible for the loss of two airships. The sister airship, C26, was lost the following day while searching for the missing C27. The non-rigid drifted into Eemnes, near the Zuyderzee, after its engine failed, resulting in the crew being interned in the Netherlands.(46) As a result of this, no airship patrols were to be flown where they were liable to be intercepted by German aircraft.
   Encounters with the "Large America" Curtiss H.12 and Felixstowe F2a flying boats often turned into running battles with the flying boats flying low over the water in order to prevent attacks from beneath. The Brandenburgs would fly alongside with the gunners trading fire over the short distance separating the two adversaries. The W.12 and later W.19 would fly mixed formations with Friedrichshafen reconnaissance aircraft. When conditions were suitable the Brandenburgs would alight and wait while the aircraft with longer endurance would search for patrolling British flying boats or ships. If it saw a formation it would try and get the British to follow it to the waiting Brandenburgs, or else call up the fighters by wireless while keeping the British engaged.
   The Brandenburgs did not have everything their own way. On 1 April 1918, two W.12 floatplanes, MNs 2102 and 2107, together with a Friedrichshafen FF49C HFT Class aircraft left Zeebrugge. According to German reports they encountered six enemy landplanes and in the ensuing fight the Friedrichshafen and one W.12 (MN 2102) were shot down. The surviving W.12 shot down one enemy aircraft and returned to the station. In actuality there were only three British aircraft but they were Sopwith Camels of No.213 Squadron, the RNAS and RFC being amalgamated on that day. No British aircraft were lost. The usual accidents associated with any military air base also took their toll. On 3 April W.12 MN 1413 collided with another aircraft while alighting. Both aircraft were destroyed and the Brandenburg's pilot, Ltn.d.RMI Johns, was drowned.
   The Germans now were active in attacking the British flying boats such that instead of a lone boat the British had to send out three and eventually up to five in order to ensure that the reconnaissance was carried out. This led to a debate within the British authorities as to what was needed to combat the new German fighters. The Curtiss H.12 had inadequate armament while the Felixstowe F.2a was more heavily armed but was still vulnerable to attacks from below. The bow position carried a single Lewis gun on a Scarff mounting, the pilot had a Lewis gun on a pivot mount, and there were three gun positions behind the wings. On each side of the hull a single or double Lewis gun could be mounted on a Gallows Mount, and in the center of the hull a Lewis gun on a ring mount. An attack from the rear and below could not be engaged from any of these positions, forcing the British boats to fly low over the water in order to prevent the Germans from getting beneath them.
   The situation became so bad that a special meeting was held in May 1918 where the British stated that "in addition to the fighting seaplanes, there were the fighting aeroplanes which came up from the German coast, and it frequently happened now that a reconnaissance was not carried out because the Boats found themselves up against a superior German formation." It was stated that three boats were required if one was to win through, and it was likely that up to five boats would be needed by the end of the summer.(47)
   Christiansen added the Curtiss H.12B serial N4338 on 15 February and Curtiss H.12 serial 8677 on 24 April 1918, to his score, and claimed another Curtiss on the 25th.
   The W.12 was popular with its crews and earned the colloquial name "Kamael", probably due to the distinctive fuselage. It remained in service alongside the W.29 until the end of the war.
   The German Naval contingent in Turkey received three W.12 biplanes: MN 2018 late in 1918 and MNs 2110 and 2112 in July 1918. Nothing further is known of their activities.(48)

(41) The out of sequence of the Marine Numbers was probably due to the bureaucracy finalising the documentation and not an attempt at confusing the enemy.
(42) The top wing had to be moved backwards 350 mm. Heinkel had a works crew carry this out overnight.
(43) Dr. Fritz Stormer served in the German Imperial Navy in WWI, first in the naval infantry, then as an observer in two-seat seaplanes based on the Flanders coast. Stormer, F. "Seaplanes in Combat", Cross & Cockade Journal, USA, Vol.20, No.2, 1979.
(44) Jones, H.A. The War in the Air, Vol.IV, P.67
(45) "The Hornets of Zeebrugge", Cross & Cockade Journal, USA. Vol.11, No.1, 1970. In fact the Porte Baby made it back to the UK and was returned to service surviving until December 1918, but the type was never used in areas where opposition from German marine aircraft could be expected.
(46) C26 came down in Holland on 13 December 1917. About 03.15 four men jumped out of the gondola at Poortugaal (SW of Rotterdam), they were brought by car to Rotterdam. Between 07.00 and 08.00 the last man jumped in the Biesbosch, opposite Sliedrecht. Local workers brought him over the Merwede River. He was brought by train at 09.00 to Dordrecht. At Wijngaarden, just north of Sliedrecht, a bomb was found. C26 ended at Eemnes-Buiten, a village about 5 km from the (then) Zuiderzee, now Gooimeer and Eemmeer.The airship caused enormous damage with broken electric and telephone lines. (Research by F Gerdessen.) For several photographs of the wreck of C26 enter www.geheugenvannederland.nl and then enter "Eemnes."
(47) Forty-Fifth Meeting of the Technical Committee, 30.05.18. Copy in NARA RG72 File O-ZS-7.The Meeting was held to discuss whether the construction of a fighting flying boat was warranted.
(48) Nikolajsen, O. Op Cit.


Brandenburg W.12 Specifications
Source Typenschau Gray & Thetford Brand. 3-View*
Dimensions in m
Span, Upper 11.20 11.20 11.200
Span, Lower 10.48 - 10.480
Length 9.60 9.6 9.605
Height - 3.3 -
Chord, Upper - - 1.800
Chord, Lower - - 1.800
Areas in m2
Wings 36.20 35.3 36.26
Ailerons 9.6
Elevators 1.8 1.50
Rudder 0.75 0.75
Empty Wt., kg 1,000 997 1,000
Loaded Wt., kg 1,463 1,454 1,463
Performance
Speed in km/hr 160 159.5 -
Time to 800 m 6 min. 6 min.
Time to 1000 m 8 min. 7 min. 8 min.
Time to 1500 m 13 min. 13 min.
Time to 2000 m 20 min. 18.9 min. 20 min.
Time to 3000 m 38.5 min. 38 min.
Motor 160-hp Mercedes; 150 hp Benz 160-hp Mercedes D.III; 150-hp Benz Bz.III 160-hp Mercedes
* Date 9.3.17, MN 1011 - 1016


Brandenburg W.12 Specifications
Source SVK MN 1014 SVK MN 1185 SVK MN 1413 SVK MN 2001 (2001 - 2019) SVK MN 2023
Dimensions in m
Span, Upper 11.250 11.200 11.200 11.200 11.200
Span, Lower 10.500 10.500 10.500 10.500 10.500
Length 8.470 9.450 8.690 9.600 9.600
Height 3.230 3.550 3.300 3.300 3.300
Chord 1.800 1.800 1.800 1.800 1.800
Stagger - - 0.220 0.225 0.128
Empty Wt, kg 857 977 959 997 1,056
Loaded Wt, kg 1,314 1,434 1,230 1,454 1,550
Performance
Time to 800 m 6 minutes 7.6 minutes 5.8 minutes 5.2 minutes 8.8 minutes
Time to 1000 m 8 minutes 9.6 minutes 7.7 minutes 7.0 minutes 11.1 minutes
Time to 1500 m 13 minutes 16.2 minutes 12.9 minutes 12.0 minutes 19.7 minutes
Time to 2000 m 20 minutes 24 minutes 20.9 minutes 18.4 minutes 30.5 minutes
Time to 3000 m 38.5 minutes - - - -
Engine 160-hp Mercedes 150-hp Benz 150-hp Benz 150-hp Benz 150 hp Benz

  
Brandenburg W.12 Production
Marine Numbers Class Engine Delivered Notes
1011 - 1013 C2MG D.III Feb. - Sep./Oct. 1917 2nd order for prototypes 22 Nov. 1916. Short fuselage.
1014 - 1016 C2MG D.III 1st order for prototypes 15 Oct. 1916. Short fuselage.
1178 - 1187 C2MG Bz.III July - Aug. 1917 1st production order Jan. 1917. Short fuselage. 1181 not delivered. 1185 long fuselage.
1395 - 1414 C2MG D.III Sep. - Dec. 1917 Ordered Mar. 1917. Short fuselage. 1413 four ailerons.
2000 - 2019 C2MG Bz.III Dec. 1917 - Mar. 1918 Ordered Sep. 1917. Long fuselage, larger wing cut-out. 2016 Hispano-Suiza, later Benz Bz.IIIb V-8 engine. 2018 to Turkey.
2023 - 2052 C3MG Bz.III Mar. - May 1918 Ordered Oct. 1917. Long fuselage. 2024 used for trials of motor machine gun. 2027 destroyed during acceptance.
2093 - 2132 C2MG D.III Feb. - May 1918 Ordered Oct. 1917. 2095 nose radiator. 2110 - 2112 to Turkey.
2217 - 2236 C2MGHFT D.IIIa Apr. - June 1918 Ordered Nov. 1917. Radio fitted.

M.Dusing German Aviation Industry in WWI. Volume 1 (A Centennial Perspective on Great War Airplanes 84)

Hansa und Brandenburgische Flugzeugwerke AG (Brand)

Aircraft Development:

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  Although the Type W.12 was completed in December 1916, weather conditions prevented it being tested until the following month. This was the first Brandenburg type with a field of fire from the observers’ guns which gave effective protection against a rear attack. The German Navy was very satisfied with its performance, and it was ordered into production.
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