Fokker Spinne

  After Bruno Buechner, Fokker's associate, destroyed the first airplane Fokker had helped build, Fokker started his first completely original design. Due to its extensive wire bracing, Fokker called this first design Spinne (Spider).
  The Spinne was a monoplane with flat horizontal tail and no vertical fin nor rudder. It was power by a 50 hp Argus engine cooled by side radiators. The monoplane wings had steel tubing framework, were swept back, and had significant dihedral for natural stability. Roll control was by wing warping. The 'fuselage' was formed of two wood longerons with wood cross braces that the engine was attached to. The pilot's seat was directly behind the engine. The general configuration was based on model gliders that Fokker had built.
  For this first original design, Fokker was in partnership with Franc von Daum, who provided funding for the engine and contributed to building it. During Fokker's test hops with the machine a number of changes were made. To improve controllability a movable elevator was added, then a vertical rudder. However, when Fokker went home to Amsterdam for Christmas 1910, von Daum, who had been prevented from trying the aircraft, attempted to fly it and crashed into a tree. Spinne I was destroyed but the Argus engine survived.
  Fokker then built a second, somewhat more advanced Spinne, using the 50 hp Argus engine from the first. This second Spinne was built in the workshop of Jacob Goedecker, another aviation pioneer who was also a qualified engineer. Goedecker assisted with detail design; however, the second Spinne was closely related to the first. Fokker fitted the second Spinne with ailerons instead of wing warping and fitted a rudder.
  Fokker taught himself to fly in this second Spinne. After gaining some flight experience he requested a pilot's certificate, which he was granted on 7 June 1911 after passing the flight test.
As part of their agreement, von Daum was to get ownership of Spinne II as soon as Fokker had gained his flying license, and Fokker was to teach him to fly. Von Daum crashed the second Spinne while flying it. Fokker, meanwhile, had been building a third Spinne at the Goedecker workshop.

Fokker Spinne

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  Von Daum crashed the second Spinne while flying it. Fokker, meanwhile, had been building a third Spinne at the Goedecker workshop.
  Spinne III was to the same basic design as the earlier aircraft, but was smaller and lighter. Despite its smaller size, Fokker built it as a two-seater with pilot in back. Spinne II had proved stable and Fokker built Spinne III with wing warping instead of ailerons.
  In 1911 Fokker went to work for Goedecker as a flight instructor. However, in December 1911 he moved to Johannistal, center of Prussian, and thus German aviation, and took Spinne III with him. In January 1912 he gave an impressive flying demonstration in Spinne III during a strong, gusting wind. His success was covered in Berliner Zeitung am Mittag and his reputation as a flyer was made. The next month he registered his company as Fokker Aviatik GmbH, although he never used this name and his company letterhead from the beginning read Fokker Aeroplanbau. Fokker then built a number of Spinne machines that differed little from Spinne III. Some had a 70 hp engine and another a 100 hp engine. Both wood and aluminum nacelles were applied for streamlining, giving these models a distinctive appearance.


Fokker M.1

  Fokker had long wanted to sell aircraft to the German Army, and in 1913 he got that opportunity. He received an order for two Spinnen, one powered by a 100 hp Argus engine (A37/13, work number 15) and the other by a new 95 hp Mercedes engine (A38/13, work number 16). The Army had issued a new requirement that all airplanes it purchased have a manufacturer's designation, so Fokker called these Spinnen the M.1, with the 'M' indicating militarisch (military).
  The aircraft powered by the Argus engine flew first because that engine was available first. Fokker successfully flew it to 600 m in 9 minutes while carrying enough fuel for a 3 hour flight. On 3 March 1913 it was flown by an Army pilot from Fokker's factory to the test center at Doberitz. Later in March the Mercedes engine was delivered and the second M.1 was completed. Fokker then flew it to Dobertiz.
  After evaluating the M.1, the Army decided it was not suitable for demanding military use and did not order any more.

Fokker M.1 Specifications
   Engine: 95 hp Mercedes
   Wing: Span 13.20 m
   General:
Length 8.60 m
Height 3.00 m
   Climb: 600m 2 min

Fokker M.6
  
  By the outbreak of war in August 1914, the German Army, like other European powers, realized that two-seat aircraft would be more effective for reconnaissance. The pilot was preoccupied flying the aircraft, so provision of an observer who could give complete attention to the task of reconnaissance could give better results.
  The M.6 was a two-seat derivative of the M.5 with the front wing spar raised 40 cm above the top longeron to give the crew a good field of view downward between the wing root and fuselage. Unfortunately, the downward view was not as good as anticipated and the cockpit was cramped.
  Power was from an 80 hp Oberursel and the fuselage was slightly longer than the M.5 due to the second seat. The pilot sat in front.
  The only M.6 was built in June 1914 and crashed on the 23rd, due to a faulty setting of the fuel cock. Pilot Oblt. Kolbe was killed and passenger Hptm. Ruff was badly injured.

Fokker M.6 Specifications
   Engine: 80 hp Oberursel U.0


Fokker M.8 (A.I)

  The M.8 monoplane was very similar in configuration to the M.6 but had the widened fuselage of the M.7, although it had a single large cockpit. The pilot sat in front. The wings were larger in span and chord to reduce wing loading and improve performance and handling. Wing warping was used for roll control. Construction was typical Fokker; wooden wings and welded steel tube fuselage and tail surfaces.
  A space was left between the wings and fuselage to give the crew a good downward view. The engine was an 80 hp Oberursel and the control column was fitted with a two-handle grip that had been standard on Fokker designs since the M.5.
  The Army bought about 80 M.8 aircraft for reconnaissance duties and gave it the military designation Fokker A.I.
  The Fliegerschule used 22 A.I, s/n S.1-S.22. Work number 97 was S.20; later it became A 20/16 when assigned to the Fliegertruppe.
  When the Fliegerschule was closed, the Fliegertruppe took over these aircraft as A.I 1-22/16.

Fokker M.8 (A.I) Specifications
   Engine: 80 hp Oberursel U.0

Fokker M.7 (B.I)
  
  The M.7 was Fokker's first successful biplane design. Fokker's earlier designs had been monoplanes, but given the primitive structural technology of the time, the biplane configuration generally offered a better combination of strength with light weight, a mix that was very important considering the modest engine power available from contemporary aero-engines.
  Power was from an 80 hp Oberursel U.0, and there were two cockpits for the crew. The M.7 was designed for the German Navy, which ordered seven aircraft. However, the Army was pressuring Fokker for a development of the M.6, which became the M.8, and because the Army bought 20 times the number of airplanes the Navy did, the M.8 monoplane was produced before the M.7.
  The fuselage of the M.7 and M.8 were nearly the same, both being about 40% wider than that of the M.6, giving the crew more room to work. The wings were a sesquiplane design with the upper wing much longer than the lower. Construction details followed the M.5 (steel tube frames for the fuselage and tail surfaces, wooden wings, all fabric covered) except for the configuration.
  The enforced delay of the M.7 meant that the prototype was not completed until January 1916. Performance was good for the time but flight experience demonstrated that the upper wing and bracing structure needed to be strengthened. The added weight reduced performance. Regardless, the Navy bought 21 examples for coastal defense flights that were designated Fokker B. The Army bought three but these were not used at the front and almost certainly were used as trainers.
  The Austro-Hungarians bought 15 aircraft. These first served at the front as unarmed reconnaissance aircraft but after a time were reassigned to training service due to their modest performance.


Fokker M.7 (B.l) Specifications
Engine: 80 hp Oberursel U.0
Wing: Span Upper 11.7m
Span Lower 7.2 m
Wing Area 26.0 m2
General: Length 8.00 m
Height 2.95 m
Empty Weight 380 kg
Loaded Weight. 679 kg
Maximum Speed: 130 km/h
Climb: 1000m 8 min
2000m 15.5 min


Fokker M.10 (B.I & B.II)

  The M.10 was a development of the M.7 biplane. The Army needed a two-seater with wireless capability for artillery cooperation, and the wing warping controls were moved aft to give the observer more room for the wireless. The wings were strengthened to carry the extra weight of the wireless. Originally an 80 hp Oberursel U.0 was fitted but the extra weight of the wireless and strengthened wings meant more power was needed for adequate performance and the 80 hp engine was replaced with a 100 hp engine. At first a water-cooled 100 hp Mercedes was tried but the extra weight of the engine and cooling system absorbed the additional power, so it was replaced with a 100 hp Oberursel U.I rotary.
  Two versions of the M.10 were built. First was the M.10E (E for einstielig = single-bay). This was normally fitted with the 80 hp Oberursel U.0, with which they were seriously under-powered. Nevertheless, the Army bought the M.10E and used it at the front. The Austro-Hungarian Army also bought 23 airplanes and used them at the front. Later both Armies used them for training after they were retired from the front. The military designation was B.I, which was the same designation as the M.7 aircraft bought by the military.
  The second version of the M10 was the M.10Z (Z for zweistielig = two-bay); this had redesigned two-bay wings and most were powered by the 100 hp Oberursel U.I rotary. The M.10Z was designated the Fokker B.II in service and was used at the front by the German Army and Navy and the Austro-Hungarian Army. After being retired from the front the surviving examples were used for training.

Fokker M.10 (B.I) Specifications
Engine: 80 hp Oberursel U.0
Wing: Span Upper 11.3 m
Span Lower 7.77 m
Chord (U & L) 1.6 m
Wing Area 28.0 m2
General: Length 7.50 m
Height 2.50 m
Empty Weight 409 kg
Loaded Weight 712 kg
Maximum Speed: 130 km/h
Climb: 2000m 25 min


Fokker B.I in Austro-Hungarian Service
Type Series Numbers Order Date
M.7 03.01,02,04-12 20 Sep. 1914
M.5L 03.03 29 Jan.1915
M.10 03.13-24 17 Oct. 1914
M.7 03.25-28 6 May 1915
M.10 03.29-40 29 Jan. 1915
Notes:
  1. Last two orders were less engines.
  2. The M.7 aircraft 03.25-03.28 ordered in May 1915 were rebuilt, not new, aircraft.
  3. Source: Austro-Hungarian Army Aircraft of World War One by Peter M. Grosz, et. al.