WNW Dr.1 engine - is it Rhone or is it an Oberursel?

[19squadron]

Researching Oberursel's so called "UR.II, it seems there is a lot of conflicting evidence. Astute observers will note that many if not most wartime pics of F,1's and Dr.1's as wwell as E.v's credited with a 110bp Oberursel UR.II are in fact fitted with a Rhone 9Ja or copy of such. Whereas some Dr.1's and Richthofen's crashed and recovered tripe engine is credited as being a UR.II but is clearly in fact a copy of the Rhone 9Jb long stroke 130bhp engine.

 

Did Oberursel in fact make copies of the short stroke 110bhp 9Ja and the long stroke 9Jb 130bhp engine and call them both "UR.II's? or Did Mr Fokker manage to salvage a hell of a lot of Rhone short stroke engines to fit to the majority of this triplanes and E.V's which are called Oberursels by mistake? The Oberusels in existence that have maker's plates, in Berlin and there is the Richthofen engine at the IWM, are both 9Jb copies and as such look very different from the pics of most Dr.1's in service which are unmistakably 9Ja's or copies of same.

 

 

- anybody got any ideas?

 

the literature is very confused, and there are no Oberursel records that I am aware of to shed light on this.

Edited August 21, 2019 by 19squadron

[Juggernut]

It has been told to me that the LeRhone engine was a prized item and many a German aircraft were retrofitted with it when the could get them.

[19squadron]

2 hours ago, Juggernut said:

It has been told to me that the LeRhone engine was a prized item and many a German aircraft were retrofitted with it when the could get them.

 

 

Yes and I wonder if that is in fact true? and not a myth?

 

and  in fact that most Dr.1's had a Oberursel copy of the Rhone 9Ja and pilots prized not a genuine Rhone but an Oberursel copy of a Rhone 9Jb, such as the one in Berlin with an Oberursel maker's plate, or the recovered Oberursel copy of a 9Jb from Richthofen's downed Dr.1 which was falsly credited as being a Le Rhone engine in april 1918 and is famously and mistakenly phgographed with a hand written sign saying "Richthofen's Le Rhone"

 

-- and that both the Oberursel copy of the Rhone 9Ja and Rhone 9Jb are called UR.II's despite them looking completely different. If that is not the case, very few Fokker E.v's and Dr.1's were in fact Oberursel engined, they were in fact Le Rhone engined, which would imply that there were a hell of a lot of recovered Rhone engines that went into German aircraft.......at the factory!

 

 the WNW site for Le Rhone/UR.II engine sprue photo archive illustrates the point.

 

 

http://www.wingnutwings.com/ww/productdetail?productid=3169&cat=1

Edited August 21, 2019 by 19squadron

[19squadron]

All the above aircraft appear to have Rhone 9Ja engines rather than Oberursel UR.II engines or Rhone 9Jb engines. I do not think this has been discussed much before - WNW have broached it in their F.1/Early Dr.1 kit, but not all the above aircraft are early Dr.1's.

[bobster]

I have been under the impression that the main difference when modeling either the German made Oberursel or the British made le Rhone was the color of the piping found behind the cylinders.  As I recall, copper color for British and sliver for German?  Are there other external cues to consider?

[19squadron]

31 minutes ago, bobster said:

I have been under the impression that the main difference when modeling either the German made Oberursel or the British made le Rhone was the color of the piping found behind the cylinders.  As I recall, copper color for British and sliver for German?  Are there other external cues to consider?

there are many Le Rhone engines -

 

But these Fokker triplanes above all have a Rhone 9Ja or copy fitted. Above a Rhone 9Ja

 

Edited August 22, 2019 by 19squadron

[19squadron]

32 minutes ago, bobster said:

I have been under the impression that the main difference when modeling either the German made Oberursel or the British made le Rhone was the color of the piping found behind the cylinders.  As I recall, copper color for British and sliver for German?  Are there other external cues to consider?

This is a genuine Oberursel UR.II. note two piece crank cover over an uprated main bearing, lightened rockers and more machining on the crankcase

[19squadron]

41 minutes ago, bobster said:

I have been under the impression that the main difference when modeling either the German made Oberursel or the British made le Rhone was the color of the piping found behind the cylinders.  As I recall, copper color for British and sliver for German?  Are there other external cues to consider?

This is a British licence built Rhone 9Jb, of which the above UR.II is a copy, and totally different from the Rhone 9Ja top. All the books etc quote the Triplanr as being fitted with an Oberursel UR.II [with odd exceptions such as Josef Jacobs Clerget Triplanes] - however this is patently not true. WNW has pointed up 9Ja's in the three F.1's and "early Triplanes [look at the expanded diagram, - but it seems to me there are many Dr.1's fitted with the smaller engine.