BMW Fokker D.VII's

[Laserlloyd]

I looked up Achim's book but I don't think it's an E-Book. I did find his CD book on his site at FTS CD Books and more

Dave,
Not sure but you can try contacting Achim and I'm sure he would give you a copy..

Lloyd...

[Frommherz]

Gentlemen,

may I throw in a few words on the earlier question of the D.VII(F) designation?

Normally one would expect a significant technical difference like a higher rated engine to be made distinguishable by addition of a small letter "a" or "b" as had been done in the cases of the Roland D.VIa/D.VIb and the Hannover Cl.III/Cl.IIIa for example. We know there never was a Fokker D.VIIa or D.VIIb. Designations like

D.VII(B) for "BMW",
D.VIIü for "überkomprimiert/overcompressed" or
D.VII(H) for "Höhenmotor/high altitude engine"

would have been likely candidates yet the chosen designation proves to be D.VII(F). I can't think of any German word starting with "F" that fits the BMW engine.
I assume that the "F" simply differentiates the Fokker-built aircraft from the D.VII(Alb) and the D.VII(OAW) after the license contracts were signed. Anthony Fokker certainly made sure, that his aircraft would be equipped with the best available engines so that Fokker-products rated high with frontline pilots. A clever marketing move with future fighter trials and contracts in mind!
This is just speculation but it would mean that the "F" denotes the BMW engine only... indirectly.

Marvellous thread by the way!
Best wishes,
Frommherz

[Dan_San_Abbott]

Hi Dave:
Sorry I kept missing your question. What I did was select 14 serial numbers or so from the missing March numbers. It is too restrictive, it could have span a larger range. I most likely was being conservative.
I have a list of engines built by the varoius engine manufactures. I will post that for those who may be interested.
Blue skies Dave,
Dan-San

[Dave_Watts]

Hi all,

Yavor,
Great numbers for the Oberursels, thanks. I'm sure one of our "in-house" experts has numbers for BMW motors as well, it sounds like Dan-San is pulling them together.

Dan-San,
Thanks for the source nomenclature of who and what were in charge of the motors.
I'm not sure about the BMW shipments to the front. I went to BMW headquarters in Germany a few years ago, and found nearly nothing, and they had no interest in WW1 or aircraft.
Remember when I visited you after one of my trips to Daimler and shared the delivery sheets and I pointed out the delivery of 10 motors directly to "Jagdgeschwader Richtofen" (as it appeared in the Daimler delivery log book) on April 22nd. I felt this must have been in anticipation of the new D.VII's coming and they wanted backup motors to make certain they stayed in the air. As a side note, this was one of the earliest usages of Jagdgeschwader Richtofen I had seen in "official" usage and before the official decloration name change.
I look forward to your motor production numbers, especially the BMW's and Opel BMW's.

Lloyd,
I'm not certain if Achim has it, I have at least six of his CD's.

Frommherz,
Spot on with your designation suggestions with other aircraft. For clarity, "F" was for BMW powered Fokker built D.VII's only. Yes, correct, the "F" albeit we think for "F"okker certainly does indirectly mean BMW. I think this lends itself to support even more this was a designation completely thought up by Fokker and implemented, otherwise we would see the usage with Albatros and OAW built/BMW powered D.VII's...and we don't! A point you are indirectly bringing up and may be part of the answer, which is, Fokker may have wanted his namesake associated with the BMW powered D.VII as he knew it was so superior. Almost like a car manufacturer that built a model that came with a six-cylinder engine or a V-12 engine, and they only had their namesake on the front of the V-12 model, as they knew it would be the star/flagship car on the street and the association. As you stated, Fokker would want to associate his namesake to the BMW powered D.VII and not the Mercedes powered D.VII. To lastly reitterate; when a pilot got into an "F" D.VII, he knew he was getting into the "P-51/Merlin" of his time, and it was built by Fokker. At least that's a good/valid rational angle for an answer to the "F" paradox.

All,

What are other aircraft that would have eaten up numbers of BMW motors, and do we have production numbers for them? As I stated, Pfalz D.XII's used a chunk, what are their numbers. Was there any production of the Dornier D.1's or the Rumpler 7D.1's? I seem to recall them using BMW's.

Best wishes,
Dave W.

P.S. I think I may have to drop the Mana motors from the equation as the power doesn't seem to be as good as the BMW. Your opinion Dan-San?

[rammjaeger]

Hannes or other experts,
I swear I've seen a list posted on the Aerodrome on one of the threads that lists total production numbers for different German flugmotors. I tried searching the Aerodrome's old threads, but no luck. Anyone have it?

I am trying to remember the kind of data and its source but can not dig deeper before next week.

After WWI the "B.M.W. 185 PS" was quite often offered as complete machine or its spares in "Flugsport" etc by business and private persons alike.
I think it is clear the German commission did not report all modern airplanes and engines to the Allied powers. Finally 1136 serial numbers of airplanes and many motor numbers were missing in the great list and Germany had to pay once 50 million Mark and then another 25 million Mark for compensation.
So one can only speculate how many BMW motors were not recorded or records destroyed and motors stolen, moved away, secretly exported etc.

1 Pfalz D.XV with "B.M.W. 185 PS" was used by enterprise Breuler é hijo in Argentina in late 1920, Swiss civil aviation used the motor with Dornier and Junkers airplanes and even the Tschech built a combat airplane Ae.04 with this BMW-motor.

[YavorD]

Originally Posted by rammjaeger

...
1 Pfalz D.XV with "B.M.W. 185 PS" was used by enterprise Breuler é hijo in Argentina in late 1920, Swiss civil aviation used the motor with Dornier and Junkers airplanes and even the Tschech built a combat airplane Ae.04 with this BMW-motor.

In 1922 Junkers delivered several F 13 with BMW IIIa, and Junkers subsidiary in Fili, Russia, couple of A 20a/aw, and several H 21 (1924) too.
Even another Fok. D.VII F is listed in 1922 as fighter-trainer from Fokker Schwerin.

Source:
Helmut Stützer, Die deutschen Militärflugzeuge 1919-1934 : mit 143 Vierseitenrissen im Maßstab 1:144
Verlag E. S. Mittler & Sohn GmbH, Herford, 1984, 240 S., ISBN 3813201848.

Regards,
Yavor

P.S. Several Fok. D.VII and Fok. C.I with BMW IIIa found his way to Russia during 1920s (source: V. B. Shavrov). Officially, after 1923 BMW IIIa engines were assembled by Junkers-Fili in Russia.

[Varese2002]

Hi Yavor, just a late reaction on the yearly production numbers -

There is an article, published by Wilhelm Hoff (Z.A.K.) in Z.VDI, 1920, and translated by NACA as Technical Note No.56 in 1921. Yerly production of aeroplane engines is quoted as follows.

Quote:
Period ............... Stationary engines ... Rotary engines ... Total
----------------------------------------------------------------------
August to December 1914 .............. 748 .................. 100 .......... 848
January to December 1915 ............ 4544 .................. 493 ........ 5037
January to December 1916 ............ 6930 .................. 892 ........ 7822
January to December 1917 ........... 10364 ................. 836 ....... 11200
January to December 1918 ........... 13757 ................ 1785 ....... 15542
-----------------------------------------------------------------------
Total ........................................ 36343 ................ 4106 ...... 40449

The authorotative [Militärgeschichtliches Forschungsamt]

Gilles, J. A., and Karl Köhler. 1971. Flugmotoren 1910 bis 1918. Frankfurt/Main: E.S. Mittler & Sohn.

Gives the following numbers

Time........................................ Production

8/1914 - 12/1915 ....................... 6,007
1916 ........................................ 7,823
1917 ........................................ 12,029
1918 ........................................ 16,402

Total to 10/30/18 ....................... 41,012
Total to 12/31/18 ....................... 42,271
Total to 2/28/19 ......................... 43,486

The total numbers do not differ greatly from the numbers presented by Wilhelm Hoff. Hoff based his numbers on the figures presented by the last inspector of flying troops (Idflieg) Colonel Wilhelm Hähnelt.

Source: Morrow, John H. 1982. German air power in world war I. ISBN 0-8032-3076-1

Kees

[Bletchley]

Here is a post-war (1921) report on a Junkers JL-6 (SL-6) with a BMW 185 PS motor (it recommends a 50/50 benzol/petrol fuel).

air force | american junkers | test pilot | 1921 | 0315 | Flight Archive

(In this case, it looks as if the BMW IIIa may have been adapted for much lower altitude civil use by replacing the altitude compensating carburettor with a 'normal' one (service ceiling is low, climb between 10,000 and 13,000 ft very slow, and there is no mention of altitude controls), with a lot of benzol used to suppress detonation in the high compression engine. The reference to frequent backfires, and also a remarkably good fuel economy, seems to indicate that it was still a lean-burn engine.)

Bletchley

[YavorD]

Thank you, Kees!
Obviously, various sources presented agree within 5 to 6 %, which is remarcably close for the subject in question.
Is it possible the Hoff (Z.A.K.) figures does not include deliveries for Kriegsmarine?

Hi, Bletchley!
Excellent observation!
Full throttle height of this particular Junkers engine is probably about 1 000 m (3 280 feet).
Also, Sparrow (NACA-TR-135) reports maximum power at about 1 500 m (5 000 feet).

Regards,
Yavor

[Varese2002]

Originally Posted by YavorD

Thank you, Kees!
Obviously, various sources presented agree within 5 to 6 %, which is remarcably close for the subject in question.
Is it possible the Hoff (Z.A.K.) figures does not include deliveries for Kriegsmarine?

Hi, Bletchley!
Excellent observation!
Full throttle height of this particular Junkers engine is probably about 1 000 m (3 280 feet).
Also, Sparrow (NACA-TR-135) reports maximum power at about 1 500 m (5 000 feet).

Regards,
Yavor

Yavor, I think it highly unlikely that deliveries to the Kriegsmarine were included. The Kriegsmarine was totally seperated from the Army (Heer).

I checked if a copy of Gilles, Jakob. Flugzeugmotoren 1910 bis 1918 could be bought second hand, but the asking price is EUR 100. here.

Kees