Fokker G.1, G.2, G.3

[blockhaj]

Hello. I didnt find a thread dedicated to this amazing aircraft so i thought i start one. I personally dont know more about this plane than an average person ho has access to Wikipedia and google pictures. I thought we could collect data and history on it for future generations to see.

Variants:
Fokker G.1 Mercury, this variant used Bristol Mercury VIII engines. It had 8x 7.9 mm FN mg's in the nose and a single 7.9 mm FN gunner in a backwards facing turret thingy. It could also a carry 300 kg bombload.

Fokker G.1 Twin-wasp, this variant is almost the same as the one above but it used Pratt & Whitney SB4-G Twin Wasp Junior engines. It also differs in that it could take a bomb load of 400 kg.

Fokker G.1 Hispano, this variant was meant for export and was prototyped. It used Hispano-Suiza 14AB-02/03 engines and differed mainly in armament and size. It had 2x 7.9 mm FN mg's and 2x 23 mm Madsen cannons in the nose along with a 7.9 mm FN mg gunner. It was apparently smaller than the dutch service variant.

Fokker G.2, No info

Fokker G.3, No info

 

[hesham]

The G.2.

 

[blockhaj]

The G.2.

Nice

 

[Apophenia]

Fokker G.2, No info

Fokker G.3, No info

The G.2 project created a series of Ontwerp numbered variants and LVA designations -- CG.2, GC.2, C.XVI, etc.
A few G.I-related project numbers ...

Ontwerp 129 = G.I precursor (smaller nacelle, various engines)
- http://www.secretprojects.co.uk/forum/index.php/topic,2740.msg86732.html#msg86732
Ontwerp 130 = G.I (HS 14Ab, then P&W Twin Wasp Junior)
- G.I prototype 'X-1' (Hispano-Suiza 14Ab)
- G.I prototype conversion & G.IB (P&W Twin Wasp Junior)
Ontwerp 135 = 1936 'Super G.1' light bomber project (Mercury VIII)
Ontwerp 138 = Enlarged G.IA for LVA (Bristol Mercury VIII)
Ontwerp 152 = 1937 T.VI ( G.I/T.V hybrid project, Bristol Hercules)
Ontwerp 154 = G.2 project variant (1939 CG.2)
Ontwerp 163 = 193? G.I observation project (DB 600s)*
- All metal construction, * some sources say DB 601s
Ontwerp 179 = 1939 improved G.I fighter project
Ontwerp 186 = 1939 G.3 project (Bristol Taurus)
- 'Indische jachtkruiser'?
Ontwerp 195 = G.2 project variant
Ontwerp 198 = G.2 project variant
Ontwerp 199 = G.2 project variant

- http://www.secretprojects.co.uk/forum/index.php/topic,2740.0/all.html

Doubtless, there are more G.I-related Ontwerp numbers ;D

BTW, IMPS Nederland has a good summary of the fates of individual Fokker G.Is.
- https://www.ipms.nl/artikelen/nedmil-luchtvaart/vliegtuigen-f/vliegtuigen-f-fokker-g1.html

 

[hesham]

That's right my dear Apophenia.

 

[blockhaj]

Did they actually convert the prototype to twin wasp engines?

 

[Apophenia]

Yes. X-2 had its Hispano-Suizas removed after one of those engines was damaged due to overheating during its fifth flight. SB4-G Twin Wasp Juniors were then substituted. Visual cues for the engine swap are a longer carb intake (compared with your attached photos at the Paris Salon), an oil cooler housing beneath the nacelle, and cooling gills.

 

[lark]

The first Bristol Mercury VII powerd G.1 was not constructed. (drawing nr. 39207 of 4 November 1936)
As Apophenia mentions "301" flew 15 minutes with Mercury VIII on 19 November 1938.
Perhaps it's interesting to know that the Mercury powered G.1 variants were a bit larger compared with the G.1 protorype.

source Fokker G.1 Jachtkruiser : Vol 1 by Frits Gerdessen,Karel Kalkman,Cor Oosterveen & Willem Vredeling. Lanasta 2011.

 

[hesham]

From the book;

Fokker G-1 jachtkruiser – Deel 1,here is a Fokker G.3.

 

[blockhaj]

Does anyone have any picture of specifikations about the bombs that the mercury and wasp could carry? Im just guessing that they carried some 50 kg bombs externally under the wings and belly?

 

[blockhaj]

A bit of a necro but for the future reader here are some cool specs for the G.1 Hispano. I should note that my sources may not be 100% correct but i thought id throw this out while i had it on my mind.

• Max speed:
  485 km/h at 3500 meters
  430 km/h at sea level.
  
  
• Climb rate:
  14 m/s up to 5000 meters
  
  
• Armament:
  2x Fixed 7,92 mm (Mauser cartridge) Madsen aircraft machine guns with 450 rounds per gun.
  2x Fixed 23 mm Madsen aircraft autocannons with 60 rounds per gun.
  1x Movable 7,92 mm Madsen aircraft machine gun with 100 round drum magazines.
  
  
• Bomb bay:
  Prototype was trialed with several bomb bay configurations during its lifetime. A 350 kg bomb was the largest type that could be fitted. The bomb bay was suited for 400 kg of bombs max.

 

[Michel Van]

The Dutch Wikipedia claimed
That Fokker wanted to use Roll&Royce Kerstel for G.1
what was refused by British government, so they went for Bristol Mercury VIII

Is this true and are there more Information about this ?
it would change the G.1 fuselage

 

[Apophenia]

The Dutch Wikipedia claimed That Fokker wanted to use Roll&Royce Kerstel for G.1 what was refused by British government...

That seems highly improbable. As far back as 1931, the Netherlands had received Kestrels from the UK for use in military aircraft. Those Rolls-Royce engines powered in-service LVA Fokker C.Vd and C.X recce-bombers and D.XVII fighters.

Other sources say that it was the Merlin that Beeling and Schatzki wanted as replacements for the poorly performing Hispano-Suiza Type 80 (HS 14AB-02) radials. It would be more understandable if the British government was unwilling to export Merlins in the late 1930s.

BTW: When you say Merlin installation "would change the G.1 fuselage", are you referring to the twin booms or the central pod?

 

[Michel Van]

This makes allot more sense if Merlin is involved

What i mean are the twin booms, who have to house the two longer heavier Engines
The Bristol Mercury VIII were small: 1,194 m by 1,307 m ø with 438 kg
The Merlins are 2,25 m long and 1,05 m high 0,78 m wide. with 744 kg

Also with 2200 hp, pushing the Fokker G.1 into league of P-38 and DH.98 Mosquito.
What needs modification in wings and fuselage to support Dog fighting with that engine power...

 

[tallguy]

This makes allot more sense if Merlin is involved

What i mean are the twin booms, who have to house the two longer heavier Engines
The Bristol Mercury VIII were small: 1,194 m by 1,307 m ø with 438 kg
The Merlins are 2,25 m long and 1,05 m high 0,78 m wide. with 744 kg

Also with 2200 hp, pushing the Fokker G.1 into league of P-38 and DH.98 Mosquito.
What needs modification in wings and fuselage to support Dog fighting with that engine power...

744kg? That seems a bit high for an early Merlin.

 

[Justo Miranda]

In November 1936 the G.I was presented at the Paris Air Show, where it caused a sensation. But it doesn't get firm orders, it's too revolutionary and expensive. So he offers it to hungry Spanish Republican buyers. After visits to Fokker's facilities by "South American" officers in March and April 1937, the Republic firmly ordered, and paid for in advance, 27 aircraft, so that Fokker could build the assembly line, and offer the aircraft, cheaper, to the austere Dutch government. The Dutch examples cost less, but they have a British engine, Bristol Mercury VIII of 830 hp, more powerful than those destined for Spain, which to avoid problems with the United Kingdom mount American Twin Wasp Juniors, capable of developing 750 hp.

But there was a possibility that the English, French or German governments would find out who the real buyers of the planes were, so Fokker convinced the representatives of the Republic in January 1938 to make a new contract, not through the Republican purchasing agency in France, the SFTA, but through Estonia. For which they had to pay them again. And the new contract was only signed by a certain Tiivel.

In any case, Fokker continues to give priority to the production of Dutch devices. At the end of the Spanish Civil War, it built only six G.1s with Twin Wasp engines, and none were delivered. In the end, in December 1939, Fokker sold (for the third time) to the Dutch government sixteen "Spanish" examples, with American engines, as a reinforcement for their own. By May 1940, when the Germans invaded Holland, Belgium, France and Luxembourg, they still had no weaponry in place. Anthony Fokker will not get to see him, he died in New York of meningitis on December 23, at the age of 49.

 

[tallguy]

Was there a Merlin, db600/601, or Hispano powered design for the G1?

 

[Justo Miranda]

Some color profiles here

 

[Justo Miranda]

Post-2

 

[Justo Miranda]

Some additional info

 

[Apophenia]

Was there a Merlin, db600/601, or Hispano powered design for the G1?

As noted in reply #4, an all-metal G.I observation derivative project (Ontwerp 163) was to be powered by Daimler Benz engines (most sources say DB 600s, some say DB 601s).

AFAIK, the only Merlin-powered Fokker project was Ontwerp 151 - a 1937 follow-on project from the built D.XXI fighter.

I'm assuming that by "Hispano powered", you meant HS 12Y ... as opposed to HS 14A radials. If so, then no.

There were other HS 12Y-powered Fokker projects - eg: Ontwerp 119, a 1934 monoplane fighter design (akin to an inline-engined D.XXI). The D.XXIII is often mentioned but that is confusion with the Ontwerp 155 powered by twin HS 12Xcrs V12s.

 

[Justo Miranda]

- Denmark (9 April 1940)​

After the declaration of war carried out by France and Britain on 3 September 1939, the Germans were forced to invade Norway to secure the iron ore shipping from Narvik.

The plan Operation Weserübung Süd, included the capture on 9 April of the Danish Aalborg airfield in northern Jutland, for refuelling the Messerschmitt Bf 110 fighters. At that time the Danish Naval Flying Service did not have a single modern aircraft to its disposition and had only nine Hawker Nimrod L.B.V. biplane fighters at the Avnø Naval Air Station.

On the invasion day the entire four squadron-strong of the Danish Army Air Service consisted of 45 aircraft based in Copenhagen-Værløse airfield: thirteen Gloster Gauntlet II J biplane fighters, eight Fokker D.XXI monoplane fighters, twenty-two Fokker CV reconnaissance/light bomber biplanes, one de Havilland Dragonfly transport and one Cierva C.30 autogyro.

The main action took place in Aalborg with launch of paratroopers from Junkers Ju 52/3m aircraft, but large formations of Heinkel He 111 from Kampgeschwader 4, escorted by Messerschmitt Bf 110 C-1, also flew over the capital, dropping leaflets to secure the quick surrender of the Danish authorities. After the air show, entirely psychological, the Bf 110 of the ZG.1 and ZG.76 carried out a mission of strafing over Værløse destroying three D.XXI and one Gauntlet and damaging three D.XXI and several Gauntlets.

The Oberkommando der Luftwaffe (OKL) had overestimated the danger of the D.XXI because of the publicity given to the experimental installation of two 23 mm Madsen cannons on the J-42 plane in May 1939. The Madsen 23x106 had a rate of fire superior to the 20 mm Ikaria MG-FF cannon used by the Bf 110 and to the Hispano-Suiza H.S. 404 cannon used by the Morane MS 406, but its powerful recoil was considered excessive to install it on the wings of a single engine fighter.

The Danish D.XXI were armed with just two 7.9 mm Madsen machine guns that fired, synchronized with the propeller, through blast tubes located between the lower cylinders of the engine, in four and eight o'clock positions. At the outbreak of war, the Danish armed forces were partly mobilised and their aircraft received camouflage painting.

The manufacture of a new series of Fokker D.XXI was considered and negotiations started with the Italian government for the acquisition of twelve Macchi M.C.200 fighters in April 1940. The construction under licence of twelve Fairey P4/34 and twelve Fokker G.1 heavy fighters in Flyvertroppernes Vaerksteder-Klovermarken facilities started, but none entered service before the German invasion.

In anticipation of political circumstances prevented the import of the Italian fighters, the Naval Shipyard Orlogs Vaerftet began working on the design of the OV-J-1 Marinejager. It was a single-seat light fighter powered by an inverted-Vee, air-cooled engine, of the type Walter Sagitta or Isotta Fraschini Delta. It would have been completely manufactured in metal, with retractable landing gear and four 7.92mm Madsen machine guns. There was also to be a fighter-bomber version, with inverted gull-wing and ventral bomb-rack.

Bibliography



Books

De Jong, P., Le Fokker D.21, Lela Presse 2005.

Dildy, D., Denmark and Norway 1940: Hitler’s boldest operation, Osprey 2007.

Mason, F., Gloster Gauntlet, Profile Publications Nº10.

Nigel,T., Hitler’s Blitzkrieg Enemies 1940: Demark, Norway, Netherlands & Belgium, Osprey 2014.



Publications

Willadsen, K., “Denmark: April 1940”, Aircraft of the Small Air Forces (SAFO), April 1990, vol.14 nº2.

Larsen, G., “OV-J-1 Dansk Marinejagerprojekt 1940“ Flyvehistorisk Tidsskrift from Danks Flyvehistorisk Forening, vol.3, 1993.

Larsen, G., “Hawker Danish Nimrod”, Wingpan, June 1993.

Aphopenia, A., “Indigenous Danish Fighter?” https://www.secretprojects.co.uk/forum/index.php?topic=5357.30

http://www.natureandtech.com/?p=3057

https://www.tapatalk.com/groups/aaminis/orlogsv-rftet-j-1-jager-naval-fighter-t48088.html

 

[Justo Miranda]

The lack of indigenous aircraft engines was the main limitation of the Dutch aeronautical industry. When Fokker started the design of the successor of the D.XXI at the end of 1937, he made it taking into account that, in any future European war, it would be difficult to access the powerful 1,000 hp engines that were already being manufactured in Germany, France and Great Britain.



It was decided that the Fokker D.XXIII would be powered by two 500-700 hp engines, allowing to increase the CAP range using only one of them. A twin tail booms airframe, with short wingspan and tandem engines, was then chosen to obtain a fast aircraft. This configuration neutralised the gyroscopic coupling of the propellers and the power plants torque effect, giving the D.XXIII superior manoeuvrability compared to the Bf 110 and Potez 63 conventional twin-engine fighters. The D.XXIII could indistinctly use air-cooled engines of the types Walter Sagitta I.S.R. (528 hp), Isotta-Fraschini Delta (700 hp), Gnôme-Rhône 14 M-4 (700 hp) or liquid-cooled Rolls-Royce Kestrel V (755 hp), Hispano-Suiza H.S.12 Xcrs (690 hp) and Junkers Jumo 210 Ga (745 hp).



The project Ontwerp 156 was also considered. It was a version of the D.XXIII propelled by two 1,030 hp Rolls-Royce Merlin II which would have been the fastest fighter of its time.



The D.XXIII prototype flew for the first time in May 1937, surpassing the 500 kph and 9,000 m ceiling, propelled by two Walter Sagitta. Hit by a bomb on 10 May 1940, it never flew again.

The construction system of the airframe was the same than that of the D.XXI, but the idea was to use a wing entirely built of metal for the production version. It was armed with two 7.9 mm (synchronized) machine guns in the fuselage and two 13.2 mm FN/Browning heavy machine guns in the tail booms.

 

[Justo Miranda]

At the beginning of 1938 the engineer Van der Eyk designed the FK.58, a more conventional fighter able to fly at 500 kph powered by a Daimler-Benz DB 600. But the Munich Agreement cancelled the availability of German engines and Koolhoven was forced to start the production of the FK.58 using Gnôme-Rhône 14 N-39 radial engines that allowed a maximum speed of 475 kph only.



Historical circumstances converted the FK.58 into the 'panic fighter' that everyone wanted in 1939. On January the French acquired the eighteen aircraft that had been manufactured, four of them with 1,080 hp Hispano-Suiza 14 Aa radial engines and four 7.62 mm FN/Browning machine guns. On 22 July the Dutch Government commissioned the production of a new series of 26 aircraft with 1,060 hp Bristol Taurus III radial engines, but the British cancelled their export (2 March 1940) using them to propel the Beaufort bombers. Ten more units that had been manufactured by S.A.B.C.A. in Belgium were destroyed by the Luftwaffe on 10 May.

Yugoslavia commissioned the manufacturing in France of forty aircraft and Finland of another forty-six, but the rapid development of the Blitzkrieg ended all these plans.

 

[Justo Miranda]

-

The Dutch Government did not expect a war with Germany and chose to manufacture the D.XXI - designed to be exported to countries with limited resources - instead of a more advanced fighter for national defence: the projected Fokker D.XXI H (23 May 1936) would have been powered by a 910 hp Hispano-Suiza H.S. 12Y-45 ‘Vee’ engine with retractable landing gear, one 20mm H.S.9 cannon firing through the propeller hub and four wing mounted 7.9mm FN/Browning M-36 machine guns.



The Fokker D.XXII fighter project was considered at the end of 1937, either with a 1,050 hp Rolls-Royce Merlin II (Ontwerp 151- 12 January 1938) or with a 1,375 hp Bristol Hercules radial engine (Ontwerp 150- 27 September 1939). The Ontwerp 152 was a variant powered by a 1,090 hp German Daimler-Benz DB 600 H engine designed for the Swiss Government.



The D.XXII would be equipped with retractable undercarriage like that of the Ontwerp 150 and armed with four M-36 machine guns in the wings and two more on the nose. These machine guns were moved to the sides of the fuselage in the Ontwerp 151. The Ontwerp 152 would have a 7.9 mm MG 17 firing through the propeller hub and four more in the wings.



Again, calculations showed that the Ontwerp 151 would have been faster than the Hawker Hurricane Mk.I and a suitable opponent for the Messerschmitt Bf 109 E. On 19 June 1939, Fokker proposed the D. XXIV version. It basically was a D.XXI with retractable undercarriage and a 1,060 hp Bristol Taurus or a 905 hp Bristol Perseus radial engines.

 

[Apophenia]

...In anticipation of political circumstances prevented the import of the Italian fighters, the Naval Shipyard Orlogs Vaerftet began working on the design of the OV-J-1 Marinejager. It was a single-seat light fighter powered by an inverted-Vee, air-cooled engine, of the type Walter Sagitta or Isotta Fraschini Delta...​

Our guesses about OV J-1 Marinejager powerplants were just that - speculation. It was later confirmed that the OV J-1 was to have been powered by a very modest 240 hp Argus As 10 inverted V8 engine.

-- https://www.secretprojects.co.uk/threads/indigenous-danish-fighter.5357/#post-416749