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

Brandenburg W 33
   Twenty-six W 33s had been delivered by the end of the war and were mostly in use at the North Sea air stations, augmenting the W 29, of which the W 33 was a larger and more powerful variant. Although spanning over 50 ft., it was remarkably clean, as may be seen from the illustration. This depicts a machine brought over to the Isle of Grain for evaluation after the Armistice, and the R.A.F. roundels may just be discerned below the wings. Engine, 245 h.p. Maybach Mb IV. Span, 15.85 m. (52 ft. 0 in.). Length, 11.10 m. (36 ft. 5 1/8 in.). Height, 3.37 m. (11 ft. 0 5/8 in.). Area, 44 sq.m. (475 sq.ft.). Weights: Empty, 1,420 kg. (3,124 lb.). Loaded, 2,050 kg. (4,510 lb.). Speed, 173 km.hr. (108.125 m.p.h.). Climb, 1,000 m. (3,280 ft.) in 5.4 min. Armament, one Parabellum and two Spandau machine-guns. One aircraft, No. 2543, fitted with cannon. Naval Nos. 2538-2563.

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

BRANDENBURG W 34 Germany

   Continuing the line of two-seat patrol fighter monoplanes initiated with the W 29, the W 34 was the final WWI development of the series of float seaplanes designed for the Hansa- und Brandenburgische Flugzeug-Werke by Ernst Heinkel and Hans Klemm. Essentially a scaled-up W 33 intended for the 300 hp Basse und Selve BuS IVa six-cylinder water-cooled engine, only one prototype of the W 34 had been completed by the end of the War. Additional examples powered by the 300 hp Fiat A 12bis engine were built after the termination of hostilities.

Max speed, 109 mph (175 km/h).
Empty weight, 3,382 lb (1 534 kg).
Loaded weight, 5,004 lb (2 270 kg).
Span, 55 ft 5 1/2 in (16,60 m).
Length, 36 ft 5 in (11,10 m).
Wing area, 527.45 sq ft (49.0 m2).

J.Herris Development of German Warplanes in WWI (A Centennial Perspective on Great War Airplanes 1)

Brandenburg W33

   Just as the Brandenburg W19 was an enlarged, more powerful development of the W12 for longer range and endurance and greater payload, the W33 was an enlarged, more powerful W29 for more range and pay load. A large aircraft, it was aerodynamically clean and strongly built, and had similar speed and maneuverability as the smaller W29, which it joined on operations in the late summer of 1918.
   The W29 and W33 enjoyed long, successful post-war careers in Denmark, Norway, Finland, and other countries needing reliable floatplanes in a demanding environment.

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

Brandenburg W33, W34, & W37

   Just as the W19 was a larger, more powerful development of the W12 biplane for greater range and endurance, the Brandenburg W33 was a larger, more powerful development of the W29 monoplane. The larger size of the W33 enabled it to carry more fuel for a longer range and greater endurance, and its greater power made it as fast. The first three W33s were powered by the 260 hp Maybach Mb.IVa, but the 260 hp Mercedes D.IVa and 275-300 hp Basse & Selve BuS.IVa were also used.
   The Brandenburg W29 went into operational service in April/May 1918 and had an immediate impact on the fighting over the North Sea. The larger W33 followed in the late summer.
   Although only seven W33 aircraft were delivered during the war, they were ordered in three classes; the C3MG, armed with three machine guns, the C2MG HFT with a fixed gun, a flexible gun, and wireless (radio) equipment, and a CK class with two fixed machine guns and a flexible Becker 20mm cannon instead of a Parabellum machine gun for the observer.
   Like the earlier W12, W19, and W29, the W33 aircraft were used primarily from North Sea air stations where they performed armed reconnaissance missions and opposed the British flying boats that were performing anti-submarine patrols. The W33 was ordered in very limited numbers and may have been an interim step to the enlarged W34. Three W34 floatplanes in the C3MG class were also ordered and delivered but were too late to serve operationally before the armistice. Drawings show the W34 had an enlarged gun ring capable of mounting a 20mm Becker cannon. Work on the similar but even larger W37 was halted post armistice and these three aircraft were not completed. However, eleven W37 aircraft, powered by the 260 hp Maybach Mb.IV, were built in Germany post-war and shipped to Sweden for assembly as the Caspar S.I, and others were built in Sweden by the Heinkel company.
   Along with the smaller W29, the W33 enjoyed a long and successful postwar career in Norway and Finland. The W33 was produced under license in Finland from 1922-1925, 120 aircraft being built. The 220 hp Benz Bz.IV was not available so 300 hp Fiat A-12bis engines were purchased from France. The first 57 aircraft built had provision for a fixed Vickers gun for the pilot, but these were not fitted to aircraft in service. The observer had a pair of Lewis guns on a flexible gun ring. Known as the IVL A.22 in Finnish service, the type served until 1936. License production of the W33 was also undertaken in Norway, 24 aircraft being delivered during 1920-1929 and serving until 1935. Most Norwegian W33s used the 260 hp Mercedes D.IVa engine.
  
Brandenburg W33, W34, & W37 Production Orders
Order Date Type Marine Nos. Qty Category Engine
24 Apr. 1918 W33 2538-2540 3 C3MG 260 hp Mercedes D.Iva
24 Apr. 1918 W33 2541 1 C2MG HFT 260 hp Maybach Mb.Iva
24 Apr. 1918 W33 2542 1 C3MG 275-300 hp BuS.Iva
24 Apr. 1918 W33 2543 1 CK 275-300 hp BuS.Iva
24 Apr. 1918 W33 2726 1 C3MG 260 hp Mercedes D.Iva
29 Aug. 1918 W34 2727-2729 3 C3MG 275-300 hp BuS.Iva
24 Aug. 1918 W37 2723-2725 3 CHFT 220 hp Benz Bz.IV

C.Owers Hansa-Brandenburg Aircraft of WWI Vol.3: Monoplane Seaplanes (A Centennial Perspective on Great War Airplanes 19)

Type W.33

   The W.33 was the most successful of the Brandenburg monoplane fighting floatplanes in terms of numbers built and length of service, and this was post-war. A larger version of the successful W.29, only 26 were in service by the end of the war. The usual power plant was the 260-hp Maybach Mb IVb, however three, MNs 2541-2543, were equipped with the 245-hp Maybach Mb IVa. The Typenschau gives the batch 2544-2563 as W.33 monoplanes; however, research by P.M. Grosz confirms these as W.19 biplanes.
   Italy received MN 2541 post-war as reparations. Post-war the W.33 was built in and served with the air services of Norway, Finland, and Latvia.(24)

(24)Nowarra, H.J., Marine Aircraft of the 1914-1918 War, Harleyford Publications, UK, 1966, incorrectly identifies the Finnish and Latvian Brandenburgs as the Type W.34.


Brandenburg W.33 Production
Marine Nummers Class Engine Notes
2538-2540 C3MG Mb.IVa 2538 CK
2541 C2MGHFT Mb.IVa Originally BuS IVa engine intended. To Italy 15.09.20.
2542 C3MG Mb.IVa Originally BuS IVa engine intended.
2543 CK Mb.IVa Also 1MG1MK Si C3MG. Originally BuS IVa engine intended.
2726 C3MG Mb.IVa


Brandenburg W.33 Specifications
Source Typenschau Gray & Thetford PMG Data MN 2543 Brandenburg 3-View MN 2543 NAF W.33 Jane’s AWA NAF W.33 Norsk Flyhistorisk Tiosskrift No.2/1996
Dimensions in m
Span 15.85 15.85 15.85 15.850 15.6 15.6* 15.6
Chord (max.) 3.25 3.250
Length 11.10 11.10 11.10 ca. 11.100 11 11.0 11.0
Height 3.37 3.37 3.370 3.3 3.3 3.3
Wing Area, m2 44.60 44 44.0 44 43.5
Empty Wt., kg 1,470 1,420 1,420 1,420 1,430 1,380 1,430
Loaded Wt., kg 2,100 2,050 2,050 2,050 2,051 1,990 2,050
Performance
Speed in km/hr 170 173 173 173 167 160 160
Time to 1000 m 5.4 min 5.4 min 5.4 min 6 min 10 min 7 min
Time to 2000 m 12.8 min 12.8 min
Time to 3000 m 22.3 min 22.3 min 33 min 35 min
Ceiling, m 4,400 4,200 4,000
Engine 260-hp Maybach 245-hp Maybach Mb.IV 245-hp Mb.IVa 240-hp Maybach 200-hp Mercedes 220-hp Benz 260-hp Mercedes
* The Army's Make II had a wingspan of 15.85 m while the Navy's seaplanes had a span of 15.6 m.


The W.33 in Norway

   The Norwegian Marinens Flyvaben (Royal Norwegian Naval Air Force) learned on the quiet that a licence arrangement to build the Brandenburg W.33 could be arranged at a reasonable price. Through the British legation in Oslo sanction for this action was obtained and a representative carrying 5,000 Norwegian crowns in cash was sent to Hamburg and Berlin. Johan Hover recalled that there
   was no Hansa Br-burg (sic) works in 1920, when I went to “an office” in Hamburg. It had been closed by (the) Peace Treaty. I don't remember any names, but there was no Mr. Heinkel, whom I met in 1927 in Rostock. I collected a complete set of drawings for the Hansa Br-burg W33 seaplane and some information and descriptions re the building lizence (sic) for the Norwegian Dept, for Defence. The Dept, could thus place orders for the “W.33” with any aircraft factory desired - chiefly the Marinens Flyvebaatfabrik. The British Embassy’s concurrence was in order.(25)
   The matter was settled in a short time and there were even some funds left over. Drawings, technical specifications, and the like were sent to Norway as diplomatic mail. Production of four seaplanes started immediately at the Marinens Flyvebatfabrikk (Naval Aircraft Factory) as the funds had been voted for the 1920-21 financial year. This was based on a 1913 plan that had still not been approved by the Defence Department. In all the Factory produced 24 of the Brandenburg seaplanes for the Navy and one for the Army.
   At Hamburg it had been learned that many semi-finished parts were available there and in the neighbourhood. These were considered scrap and so were accordingly low in price. The Norwegian representatives on the spot were able to purchase enough parts to fill several railway cars. These were transported to Norway where they were incorporated into the Norwegian aircraft.
   The plywood required for the Brandenburgs was not available in Norway and the local lumber firms would not take on the production of the small amounts required by the aircraft production program. Unlike the Finns, the opportunity to develop an aircraft plywood industry was lost. The factory had to gather plywood from four or five countries.
   The first year's production comprised F.52 to F.58, that is F.52, F.54, F.56, and F.58, the Navy using even numbers, the Army odd numbers. Water-cooled Benz engines of 220/260-hp that had been acquired cheaply in Sweden were installed. All subsequent aircraft from 1923 on were equipped with 260-hp Mercedes engines from Sweden and France. The Mercedes engines were heavier and stood up better to the rigors of service, lasting throughout the time the aircraft were in service, that is until 1935!
   F.52 made its initial flight on 25 October 1921. During the autumn and winter F.52, together with F.54 that had been completed on 1 April 1922, successfully completed all testing of the type. After the last two of the batch had been accepted, it was decided to send F.56 and F.58 on a demonstration flight along the whole coast of Norway, all the way to Kirkenes. Pilots were 1st Lt. Riiser-Larsen and 1st Lt. Lutzow-Holm with mechanics Engeland and Myhre as passengers. Petrol dumps had been arranged in advance at five convenient positions along the coast. The flight commenced on 12 July 1922, from the Horten Naval base. The total distance covered was 2,600 km in 21.5 hours flying time.
   On landing at Hammerfest on the return flight, Lutzow-Holm was asked to fly the doctor to Alta where the district doctor lay sick. This was accomplished in two hours whereas it would have taken 48 hours in a boat. The following day Lutzow-Holm made another mercy flight when he took the doctor to Simavik on Star Island where an outbreak of typhus had occurred.
   On the return flight all the coastal cities were visited and flown over. F.56 was damaged while force landing at Valder Sound due to a fuel feed blockage. Riiser-Larsen alighted some 10 meters from the water. Although the machine was "bruised" somewhat they continued, arriving unannounced at Horten on 25 July. F.58 was awarded a "Polar Star" for its exploits, and this was painted on the rear fuselage.
   As a reconnaissance aircraft the W.33 had to carry a radio and as the gunner/observer could not be spared, some of these aircraft were modified into three seaters. Space was at a premium. Armament was a fixed, synchronised Vickers gun for the pilot and a flexible Lewis gun on the rear gun ring. Sometimes 50 kg bombs would be carried as well.
   Construction started in 1920 and continued to 1929, the Marinens Flyvebatfabrikk (Naval Aircraft Factory) ultimately delivering 24 of the type to the Navy. In addition, the Haerens Flyvemaskinfabrikk (Royal Norwegian Army Aircraft Factory) at Kjeller completed the six Make II seaplanes that had been contracted to the A/S Norsk Aeroplanfabrikk in Tonsberg, but were taken over by the Army after the company went bankrupt. The Make II is sometimes referred to as a hybrid of the W.29 and W.33; however, according to J. Hover the Make II serial "509 - W.33 was one of those planes taken over by the Naval Air service in 1928, and identical with our first W.33 (Benz) and thus no "hybrid" W.29/W.33."(26) The Army factory then built another four W.33 floatplanes sometimes referred to a Make III. These latter machines went straight to the Navy in 1928 after little or no use by the Army.
   The W.33 was used in expeditions between 81° North and 73° South, between Severn Island and Bouvet in the Queen Maud region. Two Brandenburgs were sent to Svalbard in 1923, 1925, and 1928 in connection with Roald Amundsen's expeditions and flew thousands of kilometres in the Antarctic, 12,000 km in 1928 alone.
   The last W.33 in Norwegian service was written off in 1935. In the intervening years they gave sterling service. They were used by the military and also by the postal service and for fishery patrols. F.38 III had been chartered by the Norwegian postal service as N-47 from 5 August to 17 November 1931, for us on the mail route between Oslo and Gothenburg. The last aircraft on the original Norwegian civil register was N-48, an ex-Navy F.52. It was also used for air-mail flights.
   The Norwegian machines had a c/n issued by the factory, and a registration/serial number that was carried on the aircraft. This number could be used more than once on the same or different types.
   On 1 June 1928 the Coastal Artillery was handed over to the Navy and the surviving Army floatplanes were handed over to the Navy and as the Army had paid the Navy for the licence to build the type, it is reported that they were unhappy with the arrangement proposing that the Brandenburgs be operated on wheels and skis, but this was vetoed by the minister. The army and navy had separate air forces until they were amalgamated in 1942 while in exile due to the Second World War.
   The Brandenburgs were considered to be excellent in good weather and sea conditions.
   In cases of turbulence, which you often have along the steep, rocky coast of Norway, they were rather sluggish and heavy to keep steady. In case of forced landing in rough seas on account of motor cut out, we could usually get them down all right, but when drifting before the wind, the tips of the low wings had a tendency of dipping into the sea tops with disastrous result to the aircraft.
   In spin they were dangerous. Only one man, a test pilot, has managed to get her out and survive. We all knew that so as soon as there was any indication of a start of unintended spin: Nose down, full throttle and hope you had enough height to clear the drink(27)
   A W.33 had been completed by the A.S. Norsk Aeroplanfabrikk before bankruptcy and this machine entered the civil register as N-21. It was operated by the J.L. Tiedmanns Tobaksfabrik for advertising purposed after their Friedrichshafen FF.49 crashed in 1922. Christened "Tiger" this aircraft has the dubious distinction of being the first civil registered aircraft on the Norwegian civil register to be involved in a fatal accident when it crashed near Rorvik in the Namsdalen Valley on 22 July 1922, killing the two occupants.

(25) Letter from J. Hover to author, 12.06.1976.
(26) Letter from J. Hover to author, 06.12.76.
(27) Tor Kleppe, retired Commodore of the Royal Norwegian Navy "consulted a couple of other tottering veterans, and together" they came to the conclusions recorded here. T. Kleppe, Marinemuseet, letter to author, 01.12.75.


Norwegian Army Brandenburg W.33
C/N Const. Reg. No. Version Notes
1 NA 505 Make II W/Off September 1925
2 NA 507 Make II W/Off Oct. 1926
3 NA 509 Make II To Navy as F.60 with 268:15 flying hours
4 NA 511 Make II W/Off June 1928
5 NA 513 Make II W/Off June 1928
6 NA 515 Make II W/Off November 1925
57 MF 517 W.33 To Navy as F.40 II
HF 519 W.33 To Navy as F.36 II
HF 521 W.33 To Navy as F.50 II
HF 523 W.33 To Navy as F.48 II
HF 525 W.33 To Navy as F.38 in
NA = Norsk Aeroplanefabrikk; MF = Marinens Flyvebatfabrikk; HF = Haerens Flyvenmaskinfabrikk


Norwegian Navy Brandenburg W.33
C/N Registration No. Version Notes
35 F.52 R2 Became civil N-48 in 1931
36 F.54 R2 Total loss 30.07.25
37 F.56 R2 Total wreck, Valders, 24.07.22
38 F.58 R2 W/Off 28.07.26, midair collision
41 F.14 II R2 Total wreck 25.07.25
42 F.16 II R2 Scrapped 18.11.33
43 F.18 II R2 Fatal crash 30.07.28
44 F.20 II R2/R3 W/Off 25.08.33. Crash two killed
48 F.56 II R2 Total wreck 05.07.26
49 F.22 III R2/R3 Total wreck 06.07.31
50 F.24 II R2/R3 Scrapped 06.09.35
51 F.32 II R2 Scrapped March 1935
52 F.34 II R2 Total wreck 17.09.28
55 F. 14 III R2/R3 W/Off 16.09.25. Fatal crash
57 FAO II R2 Ex-Army 517. Scrapped March 1935
58 F.14 IV R2/R3 Total wreck 23.10.30
62 F.54 II R2/R3 Total wreck 24.08.32
65 F.56 III R2 Total wreck 16.08.29
66 F.58 II R2 Scrapped March 1935
71 F.10 IV R2 Scrapped 26.04.34
74 F.26 II R2 Scrapped September 1935
75 F.28 II R2/R3 Scrapped March 1935
76 F.30 II R2/R3 Scrapped March 1935
- F.36 II R2/R3 Ex-Army 519. Reserve March 1935. W/Off December 1937
- F.38 III R2 Ex-Army 525. Charted as N.47 in 1931. Scrapped March 1935
- F.48 II R2 Ex-Army 523. Total wreck 12.07.29
- F.50 II R2/R3 Ex-Army 521. Scrapped March 1935
78 F. 18 III R2R3 Scrapped 18.11.33
- FAO R2 Ex-Army 509. W/Off June 1932
79 F.34 III R2/R3 Fatal crash 14.01.31

  
The Industria Valtion Lentokonetehdas A.22

   After the events of 1918-1919, the Finnish aviation corps could only be described as being a mess. Aircraft had been collected from abandoned Russian and German bases. As French political influence was important in helping the new nation gain recognition, Finland purchased 20 Breguet 14 biplanes and 12 Georges-Levy flying boats from France. By 1920 the seaplanes were found to be dangerous and a complete failure. The country wanted reconnaissance aircraft for land and sea, single-seat fighters, and bombers. Finnish pilots, trained in Germany, were in favor of the Brandenburg W.29 and the government tried to obtain these from Germany; however, the Allies refused.
   Lt. Paul Hjelt then purchased a licence to construct the W.33 for 400,000 FM (Finnish marks) on 14 May 1921, in Hamburg, the aircraft to be manufactured at the projected Industria Valtion Lentokonetehdas (State Aircraft Factory) usually known by its initials as IVL. Hjelt, chief technical officer of the air arm, was chosen to go to Germany to handle the handover of plans and technical data. He was an excellent choice as he had graduated from a technical university's chemistry department in 1917, had trained as an observer in Germany, and had received flight training in France in 1920. He had also studied aeronautical engineering in Paris.
   Hjelt checked the blueprints and paid for the licence agreement but could not take the blueprints with him as the permit to do so had been forgotten and left in the Foreign Office's safe. They were later sent via diplomatic pouches. Much work had to be done to translate the instructions into Finnish and redrafting the blueprints. Gunnar Semenius did this task at night in his parent's kitchen which he later described as "the first drawing office of the Aeroplane Factory." There was urgency in this task as it was feared that the French might insist that the plans be returned to Germany. Building a German aircraft was a political issue and Finland's continued independence was dependent on foreign influence. Some of the material, such as stress calculations, had to be obtained secretly. Brandenburg had made several modifications to the W.33 that were not evident on the plans provided. All other equipment such as armament, instruments, etc., had to be obtained elsewhere. The licence was only for the airframe but did not include a royalty no matter how many aircraft were produced.
   As part of the agreement, six German craftsmen, under Ernst Schneider, went to Finland to assist in setting up the production line. The aviation dock at Santahaminna was the most logical place to establish the factory; however, the establishment of the aircraft factory had to be done on the cheap, as there was not enough capital to allow for a new facility. The factory was set up at Suomenlinna dry dock located outside Helsinki. Only two machines could be hungered indoors at the same time, so final erection was done outside prior to a test flight. A woodworking department was set up in the Suomenlinna Fortress. An assembly hall was found by forcing the protesting Uudenmaa Regiment infantry out of their garrison building.
   Parts were manufactured and partial assembly began in the summer of 1922 under Production Manager Gunnar Semenius and the German staff. It took about six months to obtain or build all the jigs and equipment needed to commence manufacture. Attempts to obtain 220 hp Benz engines failed and the 300 hp Fiat A-12bis was selected Initially they cost 48,000 FM each, but later surplus engines obtained from Versailles were only 10,000 FM each. A total of 221 engines were purchased, some used, and all requiring Finnish modifications, such as stronger con rods, before use. Changing from the Maybach meant that there were changes required to the engine beds, radiator circulation as the frontal radiator of the W.33 was abandoned and French Lamblin radiator "eggs" were situated under the fuselage. This enabled a neater cowling to be fitted which improved the Hansa's looks. In addition the fuel and oil systems had to be redesigned. The A.22 was taller than the W.33 due to the increased height of the Fiat engine. The pilot's cockpit was relocated and the observer's cockpit had a French gun ring for twin guns.
   The W.33 had a light-weight structure that was complicated and difficult to manufacture, demanding high standards of construction. The result was a good performance for the available horsepower. The manufacture of the W.33 introduced much new technology to Finland. The fuselage was constructed around four longerons that were spindled to narrow at the rear. The fuselage was ply covered with diagonal stiffeners between the frames. All joints were glued, with copper rivets and brass screws being used in some locations. The early aircraft were built using plywood and material imported from Germany.
   The wing was difficult to manufacture, each of the 22 ribs being different in section and chord. The ribs were constructed of birch plywood with ash strips. The templates for the ribs were especially demanding as there were over 100 different radii and all had to be very accurate. The box spars were of spruce with steel spacers and steel bracing. Control surfaces were of steel tube. Wing and control surfaces were covered with doped fabric. Control wires were run inside the structures to minimize drag. The floats were constructed in a similar manner to the fuselage and comprised watertight compartments. The struts that carried the wings and floats did away with external cable bracing to reduce drag.
   Known as the IVL A.22 in Finnish service, the first W.33 or "Hansa" was rolled out on 15 October 1922. This machine, 4.D.1 was first flown on the 21st by Lt. Tauno Hannelius with the Factory Foreman Osaka Sorsa as passenger. Semenius recalled that this was not necessarily the first flight as one Saturday after the day's work, the machine was taxied towards Harmaja when it rose to about 50 m but landed directly ahead, perhaps an unintended first "flight." Hannelius stated afterwards that the "speed was terrific."
   Performance trials were carried out in November 1922. With a French airscrew the machine climbed better than the original W.33. With the later standard Finnish airscrew the climb was poorer but the speed was faster. Hannelius tested the first two A.22 floatplanes, all the rest being test flown by Georg Jaderholm. Finland was to be the major user of the W.33, the factory constructing 120 in four years in batches of six at a time. Minor differences occurred between batches with different equipment being installed. Early aircraft had Lamblin radiators slung under the fuselage. From early 1924, commencing with A.22 No.27, a frontal radiator was installed. The first 57 aircraft had provision for carrying a fixed synchronised Vickers machine gun, but these were removed in 1925. The US Counsel provided a report on the IVL A.22 in January 1923, wherein he noted that the "on account of its high speed and heavy armament it approaches the fighting machine rather than aeroplanes completely used for reconnaissance."(28)
As production continued the number of manhours to build a machine was halved. This was achieved by contract out parts, having ample spare parts available at all times, and by the acquisition of the necessary skills by the workers.
From the 60th seaplane the airframes were stored as the numbers required for operations were in service. Machines were delivered directly to the air force to replace aircraft written off in accidents or returned to the factory for repair. Production was to cease after 78 monoplanes were completed at the end of 1925. The factory was to then manufacture an indigenous fighter but this project failed and more Hansas were constructed to keep the factory occupied. In all 120 Hansas were constructed, the last being delivered in July 1926.
   The Hansas were the subject to many modifications in their long service. Supply difficulties with obtaining Lamblin radiators led to the development of a frontal radiator in 1923. Nose heavy aircraft had their elevators fitted with ground adjustable trim tabs and an extension to the leading edge of the horizontal stabiliser. On aircraft No. 69 a reduction in weight of 19 kg was achieved by replacing the 3 mm aspen plywood of the rear fuselage with 1.5 mm birch plywood, and the front fuselage ply with 2.5 mm birch plywood, the Germans had used 1.5 mm and 2.5 mm aspen plywood respectively in these locations.
   The W.33 had been designed as a light wartime machine with a short life, and when machines came up for overhaul after three years service they were in such bad condition that it was recommended that they be struck off rather than waste funds refurbishing them, and as new machines were in storage. Poor quality plywood had rotted and warped. Frames had broken. In 1927 the cost of a full overhaul was 50,000 FM, that was 30% more than a new aircraft from the final production run.
   The A.22 gave Finland an aircraft that suited its requirements and it had a marked influence on the development of Finnish aviation. The 1920s was described as the "golden age" of the Hansas when there was much freedom in mission orders and flying was even irresponsible in some cases. No parachutes or seat belts were used.
   There were 42 fatalities in 20 accidents with the floatplanes. The A.22 floatplanes saw long service, 20 being written off in fatal accidents. IL-91 was lost due to a mid-air collision on 21 May 1928. Part of a formation flight, one of the aircraft flew too close to IL-91 striking the aircraft and breaking the elevators. The machine went into a dive, throwing the passenger out. He fell through the roof of a school. The aircraft plunged into the streets of Turkinsaari and burst into flames that engulfed a motor car. Two civilians as well as the two crew members were killed as a result of this accident.
   The A.22 was used at every naval air station in Finland. By the end of 1932, 105 had been written off. The last service public appearance of the machine was on 3 August 1935, at the Sur-Merijoki air show. Total flying time racked up by the A.22 was about 35,000 hours with several having over 700 hours and IL.48 leading with 801 hours.
   Latvia requested two 260-hp Maybach powered Hansas in 1926 following a tour by the A.22 floatplanes in Latvia. This request was examined but the modifications were too great to warrant for a mere two machines. Two of the IVL monoplanes, c/n 99 and 100, were delivered in December 1926, and received the Latvian serials Nos. 12 and 13. Both machines crashed attempting to alight in heavy fog on 4 March 1927. The wreckage was so destroyed in the recovery operation that it was little help in reconstructing the two aircraft, so Karlis Irbitis and his team used measurements of the wrecks and what little technical advice they could get from Finland to reconstruct the two aircraft. Returned to service in 1928 they were operated for a number of years by the Naval Aviation unit at Liepaja. They were struck off on 10 August 1933, although other reports state this occurred in May 1936 when the Naval Aviation Division was reorganised.(29) There were only 120 FVL A.22 floatplanes built. The total of 122 usually quoted comes from the fact that the Latvian ones are counted twice.
   One IVL A.22, No.2, survives in the Finnish Aviation Museum, Helsinki, the only surviving Brandenburg monoplane.

(28) G2 Report "Aviation in Finland," dated 23.01.23. Copy in Smithsonian NASM Technical File AI-90000-01 IVL (Finnish National Aircraft Factory) A-22.
(29) http://latvianaviation.com/IVL_A22.html, 16.07.2005.


   The Finns used a rather cumbersome serial system that changed over the period the A.22 was in service. The number 4 designated the role of the aircraft, in this case maritime reconnaissance, while the letter designated the year of manufacture, E meaning it was constructed/purchased in 1923. The system was changed on 1 June 1927, with each aircraft receiving its own serial designator, the A.22 receiving IL. All surviving aircraft received a new serial with gaps for write-offs and exports.
Year Serial
1922 4D.1 to 4D.2
1923 4E.3 to 4E.26
1924 4F.27 to 4F.66
1925 4G.67 to 4G.106
1926 4H.107 to 4H.120


Type W.34

   The W.34 was a slightly larger version of the W.33. Three were ordered, MNs 2727-2729, but only MN 2727 was completed, the other two were waiting their 300-hp Basse und Selve BuS.IVa engines when the war ended. MN T7T7 was taken over and tested by the French post-war but no documents as to the trials has been found to date. According to Green and Swanborough some were fitted with 300-hp Fiat A.12bis engines after the Armistice but this has not been confirmed. Even Heinkel's Typenschau lists the Fiat engine. The post-war versions of the W.33 built in Norway and Finland used the Fiat engine and this may have led to the statement that it was used in the W.34.

Brandenburg W.34 Production
Marine Nummers Class Engine Notes
2727-2729 C3MG BuS.IVa Only MN 2727 completed


Brandenburg W.34 Specifications
Source Typenschau P.M. Grosz Data Brandenburg 3-View MN 2727 (Dated 1919)
Span, m 16.60 16.60 16.600
Chord (max), m - 3.43 3.425
Length, m 11.10 11.10 ca 11.100
Height, m - 4.21 3.370
Wing Area, m2 49.00 49.0 49
Empty Wt, kg 1,534 1,534 1,534
Loaded Wt, kg 2,270 2,270 2,270
Speed in km/hr 175 ca 175 ca 175
Engine 300-hp Fiat* 300-hp BuS.IVa 300-hp Puss (sic)
* The Fiat engine was fitted to the W.33 & IVL A.22 post-war.


Type W.37

   An enlarged monoplane derived from the earlier W.29 to W.34 series of floatplanes, three prototypes were ordered in August 1918. When the Navy stopped work in December only one fuselage had been completed, however, with design refinements this machine eventually appeared as the Caspar S.I post-war. Jane's All the World's Aircraft noted that the S.I "is derived from the Hansa-Brandenburg sea-monoplane so well known during the war." The modifications introduced since the war were the installation of a roomy cabin for four passengers, a better mounting of the engine to facilitate inspections, a stronger undercarriage and improved float design. Instead of the 260-hp Maybach Mb.IV previously fitted, a Mercedes D.IV of the same horsepower was fitted. The version being built for the Swedish Navy was stated to have the 240-hp Siddeley Puma engine, and one model was to be built with the Rolls-Royce Eagle IX engine.
   The S.I was built in Germany and smuggled in parts to Sweden where it was assembled at the Svenska Aero AB in Hastholmen, the company started by the pilot Clemens Bucker. This aircraft was taken on charge by the Swedish navy as the Hansa-Brandenburg Type 31 after its Swedish serial No.31. Test flown over about 11 months it accumulated only 29 hours and had at least three different engines during this time. It was written off on 29 June 1927. The type was to be built in Sweden as the Hansa-Brandenburg Type 32 and serials Nos. 32 to 41 were allocated to the type. One civil Caspar S.I was used in Norway. This was N-23, ex-German D-292, that was registered in 1923 but crashed 15 August 1924.


Brandenburg W.37 Production
Marine Nummers Class Engine Notes
2723-2725 CHFT Bz.IV Work stopped December 1918


Brandenburg W.37 Specifications
Source Typenschau P.M. Grosz Data Caspar S.I (Jane’s ATWA)
Span, m 17.70 17.70 17.5
Chord (max), m - 3.52 -
Length, m 12.39 12.39 12.65
Height, m - 4.15 3.85
Wing Area, m2 55.00 55.0 52.5
Empty Wt, kg 1,500 1,500 -
Loaded Wt, kg 2,177 2,177 2,600
Performance
Speed in km/hr 155 ca 155 165
Climb to 1000 m - - 7 min
Ceiling, m - - 5,500
Engine - 220-hp Bz.IV -
Note: The Typenschau refers to the W.34 as the S.I = Heinkel He 1.

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:

<...>
  The last Brandenburg machine which was produced in any quantity was the W.33 of mid-1918, a larger and more powerful development of the W.29. Twenty-six aircraft had been delivered by November, 23 powered by the Maybach Mb. IVb of 260 hp. and 3 fitted with the Maybach Mb.IVa of 245 hp. (Some sources state that these machines were, in fact, W.29’s; that the latter three machines were fitted initially with the 300 hp Basse und Selve BuS.V, and that these engines were later changed to 260 hp Maybachs in order to standardise the power plant. No information on these statements is available).
  The W.34 was a slightly larger version of the W.33 and was powered with the 300 hp Basse und Selve BuS.V engine. Six were ordered, but only one example was completed, five were awaiting installation of power plants at the Armistice. The W.34 was the last Brandenburg machine completed in Germany in 1918.
<...>
  Brandenburg Types W.36 and W.37 were projects and although the former never got beyond the layout stage, the latter was eventually built in 1921 as the Caspar S.l (or He.l).