Fokker Triplane variants?

[keithjs]

With reference to the 2 forthcoming kits from Wingnuts, what would be the actual difference between an 'early' version and a 'late'?  All I can really find is they have a  different engine? Thanks in advance.

Edited September 17, 2019 by keithjs

[europapete]

Hi Keith, the early kit is of the F1, which could be considered production prototypes, and 3 were built. The late kit is the standard production Dr1. The main differences are the tailplane, which has a curved leading edge on the F1, straight on the Dr1. No wingtip skids on the F1, a narrow lip under the cowl and smaller ailerons on the F1. There are a bunch of other small detail differences such as access hatches etc too, but these are the main ones. Regards, Pete in RI

Edited September 17, 2019 by europapete

[europapete]

With regards to the engine, they all had the same type. Only Voss's F1 had a captured LeRhone installed, as they were more powerful and reliable than the stock Oberusel. 

[keithjs]

Thank you Pete. Much appreciated. I think I shall go for the 'late' version then...

[Tony Edmundson]

the early version will have large 'elephant ear' aileron balances and the cowling on the F1s were different in hole placement  as well.

 

Tony

[Jure Miljevic]

Use of captured rotary engines in Dr.I by Germans was a common occurrence during WWI. I believe von Richthofen's Dr.I 425/17 also had captured Le Rhone installed. Jacobs' Dr.I 450/17 had license built Clerget, complete with Camel's propeller, and his other black triplane had also been equipped with captured engine. Reportedly Jacobs offered a case of champagne for every reparable engine, ˝supplied˝ by front line infantry units. Cheers

Jure

[Kev The Modeller]

How interesting and makes perfect sense.

[Tony Edmundson]

On 9/25/2019 at 9:16 PM, Jure Miljevic said:

Use of captured rotary engines in Dr.I by Germans was a common occurrence during WWI. I believe von Richthofen's Dr.I 425/17 also had captured Le Rhone installed. Jacobs' Dr.I 450/17 had license built Clerget, complete with Camel's propeller, and his other black triplane had also been equipped with captured engine. Reportedly Jacobs offered a case of champagne for every reparable engine, ˝supplied˝ by front line infantry units. Cheers

Jure

Richthofen's 425/17 had a Oberursel engine, NOT a Le Rhone.  It sat at the IWM for years.   Never heard that Jacobs had two Clerget Triplanes either.

 

Tony

 

[Jeff.K]

my understanding is that the 'early' kit will be buildable as early production Dr.Is, not just the F.I. 

it's interesting that WNW admitted to caving in to demand for this kit... also the number of repops issued lately seems to indicate another shift, toward behaving more like a mainstream company and less like a limited run company. dropping Albatri when an Albatros is still available is something new for them. 

[Kev The Modeller]

2 hours ago, Tony Edmundson said:

Richthofen's 425/17 had a Oberursel engine, NOT a Le Rhone.  It sat at the IWM for years.   Never heard that Jacobs had two Clerget Triplanes either.

 

Tony

 

Having given this some more thought, I can see the logic behind using a captured engine if it's more powerful and reliable as stated above.  That said their use also poses other issues like spare parts, manuals etc as I said very interesting and worth some more research.       

[Pauls9cb]

Adding to Tony Edmundson's earlier comment about the ailerons, my understanding was that the F1s and the early Dr 1s had ailerons of type a and that later in the production run a different type (Type b) were fitted. The difference was that with type a, the aileron chord gradually increased from the inboard point where it joined the uper wing mid section, created by having the aileron rib nearest the mid section shorter than the 5 outer aileron ribs. In tpe b, all the aileron ribs had the same chord. Nobody seems clear why or when the change was made, but the effect was a slight increase in the ailerons' area and a resulting increase in sensitivity. Examples are also known where both type a and type b ailerons were fitted while in service, Dr 1 144/17 W Nr 1856 being one well illustrated example. There were also some internal strengthening fittings to the upper wing following the withdrawal from service of the first batch of Dr 1s after serious and fatal wing failures. I guess some of these may have been visible through the wing fabric but that's perhaps too much detail. Paul Leaman's book goes into much detail on a lot of this. Well worth it if you can find one. Paul

[Jure Miljevic]

Hello

I stand corrected. There is a post-war photo, published in Peter Kilduff's book The illustrated Red baron, which shows the engine of von Richthofen's Dreidecker on display, complete with a sign which reads: ˝Le Rhone engine. Horse power 110 Maker's No 2478 ...˝. Probably this had been done deliberately as U R IIs were copies of Le Rhone 9J anyway. Kilduff correctly captioned the photo as showing U R II engine, but I glanced over it without reading it properly, so ...

Tony, in his book ˝The Fokker triplane˝ Alex Imrie published this photo of Josef Jacobs, standing in front of one of his Dr.Is, which is clearly equipped with British license built Clerget and Sopwith Camel's propeller. In caption Imrie states that 450/17 and 470/17 ˝were both periodically powered by captured Clergets˝. It is suggested that ˝The machine shown is probably 470/17 ...˝, but I suspect the photo actually shows 450/17 after the repaint (note thin white Balkenkreuz outline, just visible on the upper surface of the lower left wing). Given that both Jacobs' triplanes survived almost to the Armistice, Imrie's claim about their engines sounds plausible.

Kev, for the first two years of war Germany relied on Oberursel produced copies of French Gnome and did not start developing their own rotaries until mid-1916. Two years later this resulted in several outstanding new engines, including impressive over-compressed double-rotary Siemens-Halske Sh.IIIa, but it was too little, too late. Rotaries that came from Austro-Hungary were far too few in numbers and while a well-known ˝Swedish connection˝ story makes for a very entertaining reading, it had been rebuffed many times over. Desperate times call for desperate measures so it is probably not surprising Germans resorted to use of captured engines. An added bonus with Le Rhones was the ability of these engines to run reasonably well even on substandard castor oil substitute Volt-Öl. Cheers

Jure