BMW Fokker D.VII's

Dave_Watts · 4 November 2009, 01:15 PM

Hi all,

I thought I'd go ahead and post this on a separate thread.

First off I go into the possibility of MvR having flown a D.VII at the front.

Secondly I go into the markings of early D.VII's including BMW powered examples.

When was it they switched lettering formats on BMW "F" designated D.VII's?

Was it the early format on the first Fokker batch only, then the later format on the subsequent batches?

"Fok. D.VII 294F"

"Fok. D.VIIF 4252"

Let me state up front from the evidence we have at this date and time, there is no proof that MvR flew a D.VII in combat or one was delivered to him before his death. The number one statement against delivery is there is no photographic evidence of MvR with a D.VII to support it and the interest of this potential photo-op would have been too good to have been passed up by other pilots or even Fokker.

My point of discussion was more of a "what if". Logistically there is no reason MvR could not have had a D.VII before April 21st.

Mercedes must have had a fresh wet ink order from the Armee to send motors to Fokker before they were shutting the gates at the airfield at Johannestahl and closing the 1st D class Fighter Trials around February 19th, as we have Daimler shipping 10 D.IIIa motors on February 22nd. Another 10 were shipped on March 4th, 11 on the 5th, 9 on the 8th, 10 on the 11th, 9 on the 19th, and 10 on the 20th to close out March shipments totaling 69 motors.

The Armee Acceptance sheets for Fokker are missing for the months of February and March. From reverse logic of utilizing the other remaining acceptance sheets we can subtract the known acceptances from the pool of aircraft ordered from the Armee and believed to have all been delivered, we can deduce the aircraft that were accepted in the unknown months of.February and March to be 24;

227/18 = V.11/i or V.11/ii tested to destruction for type test.
228/18 = V.18 brought up to final D.VII form standard.
229/18 = V.21 considered to be the true D.VII final form.
230/18 = Aircraft submitted by Fokker to Adlershof, I believe covered by Adlershof and then given to Albatros.

232/18
233/18
234/18
235/18
236/18
237/18
238/18

240/18

242/18
243/18
244/18
245/18

247/18
248/18
249/18
250/18

252/18
253/18
254/18

256/18

The above missing sequential aircraft numbers are to be found in the listings of aircraft accepted in later months from Fokker. Logistically, I don't see how anyone can argue that one of these above accepted aircraft couldn't have gotten to MvR, if the "powers that be" wanted it to happen.

I've used the case of the two solitary F.I triplanes being rushed to the front as evidence that if it was deemed that a D.VII was ordered to be in the hands of MvR ASAP, they at the least could have gotten either 228/18 or 229/18 on the airfield at the front.

Michael Backus wrote earlier in the thread he refernced from acepilots.com.

Manfred von Richthofen, a great influence on German fighter plane development, looked forward anxiously to the D VII, writing Kogenluft on April 2, 1918:

"When can I expect to receive the [new] Fokker biplanes with the high compression engines? The superiority of British single-seat and reconnaissance aircraft makes it even more perceptibly unpleasant here. Their single-seaters fight by coming over at high altitudes and staying there. We cannot even shoot at them. Speed is the most important factor. We could shoot down five to ten times as many if we were faster. ... Please give me news soon about when we can count on the new machines."

Most likely MvR is referring to the new high-compression Mercedes motors, but with his plea, they likely would have known he would prefer a BMW.

This lends credence to the likelihood since MvR did not receive a D.VII before his demise, I would speculate 231/18F could be considered the best candidate of the intended aircraft for MvR. It was the first D.VIIF to have an early "experimental" BMW motor (Nr.V.5) and it wasn't until May 3rd that the 2nd BMW (Nr.1236) powered D.VII, 323/18F was accepted. 231/18F was accepted April 25th, (note just days after MvR's death), but it appears it was very likely used by Fokker as far back as March for demonstration purposes.

Fokker retained 229/18 = V.21( Mercedes powered) and 231/18F (BMW powered) as "yardsticks" (or maybe better stated "Meter sticks" in this case), to measure against the other new aircraft at the 2nd D Fighter trials, and ol' 231/18F was still on hand at the 3rd D Fighter trials.

The argument could be made that since Fokker retained 229/18 and 231/18F he would have done the same even if MvR survived, and then we would look at the first BMW powered D.VIIF's as "best bets". Let's go with Lloyd's posting of May 20th JG1 receiving D.VII's as the first known shipment of D.VII's to the front. On that basis here is a listing of every possible one;

294/18F Accepted May 8th BMW Nr.1234
314/18F Accepted May 4th BMW Nr.1229
323/18F Accepted May 3rd BMW Nr.1236
325/18F Accepted May 3rd BMW Nr.1232
362/18F Accepted May 3rd BMW Nr.1239
367/18F Accepted May 8th BMW Nr.1241
369/18F Accepted May 7th BMW Nr.1242
371/18F Accepted May 10th BMW Nr.1240
377/18F Accepted May 15th BMW Nr.1244
378/18F Accepted May 15th BMW Nr.1243

It could be argued the last two D.VIIF's being accepted on the 15th of May would be too late to make it into the shipment to arrive at the airfield on the 20th...it's close, (all other BMW acceptances were after the 20th and therefore not possible), I went back and looked at the photo from Peter Kilduff of JG1 and you can see "325/18F" and "377/18F" in the aircraft lineup, so May 15th made it with the others.

As an aside tie-in, I discussed in a previous thread on D.VII white serial numbers, these aircraft would have either had black serial numbers with streaky finished fuselages, while others would have had white serial numbers with streaky and/or lozenge covered fuselages.

227/18 - 305/18 = black "bestell" serial numbers
306/18 - 314/18F = so far unobserved
315/18 - 377/18F = white "bestell" serial numbers
378/18F = so far unobserved
379/18 onwards = back to black "bestell" numbers

227/18 - 373/18 = streaky finish fuselages
374/18 - 376/18 = so far unobserved
377/18F onwards = lozenge finish fuselages

Don't forget my questions at the top of the posting concerning the "F" marking format.

Best wishes,
Dave W.

Laserlloyd · 4 November 2009, 06:41 PM

I found this reference in Dan-San's article 'Fokker D.VII in Service"

Dave,

As I don't know anything on the "F" reference but looking at May Acceptance sheets what is the difference from the engines that you have listed in the 1200's to the ones in 41000 range as in 358/18 engine Nr.41263 on the 14th of May? Is this a different engine type?

Thanks.

Lloyd...

YavorD · 5 November 2009, 05:21 AM

Quote:

Originally Posted by Laserlloyd

... looking at May Acceptance sheets what is the difference from the engines that you have listed in the 1200's to the ones in 41000 range as in 358/18 engine Nr.41263 on the 14th of May? Is this a different engine type?
...

Nr.41263 belongs to an engine from Daimler (Mercedes) D.III family, not a BMW.
Regards,
Yavor

Dan_San_Abbott · 5 November 2009, 12:59 PM

Gentlemen:
Adding to what Dave Watts posted, there were 19 Fok.D.VII listed on the Front Bestand for 30 April 1918. While none were issued to any Jasta on that date, would imply they were at the Armee Flugpark 18 being processed for issue to Jasta 10 and other Jasta.
Blue skies,
Dan-San

Dave_Watts · 6 November 2009, 11:19 PM

Hi All,

Dan-San, thanks for the input of the Frontline number/date and the clarification of AFP 18 as cited by Lloyd, thanks Lloyd.

Dan-San, do you think the range you cited as "231/18 - 245/18" is too restrictive as those first delivered to Jasta 10/JG1? I assume your range came from observed aircraft in the Friedrich's wreck photos?

Is the Kilduff photo of JG1 showing 325/18F and 377/18F later and is showing aircraft delivered later?

Lloyd, the "F" designation is something that appears to be utilized by only Fokker in the lettering of Fokker D.VII's with BMW motors. Albatros/OAW did not utilize this lettering. I don't believe I've ever read a source explanation for it. The speculation is, the "F" designation is for the aircraft being built by Fokker and it carried a BMW motor. The speculated reason for Fokker to do this is he was trying to lay claim to the BMW motor and this would be a way for the BMW to find its way back to him if the aircraft was found to be non-airworthy, but the motor salvageable! I really don't know if that is true and if it worked.

We do have some supporting evidence from the Armee Acceptance Sheets repeated acceptances of the same BMW motor in different Fokker D.VII's;

BMW Nr.1247 D.VIIF 4364/18 Accepted August 21st
BMW Nr.1247 D.VIIF 5121/18 Accepted September 13th

BMW Nr.1248 D.VII 450/18F Accepted June 4th
BMW Nr.1248 D.VIIF 7685/18 Accepted October 14th

BMW Nr.1282 D.VII 494/18F Accepted June 17th
BMW Nr.1282 D.VII 502/18F Accepted June 19th
(I believe the above motor number is a typo on one of the aircraft, (likely 494) should be motor Nr.1281, acceptance dates too close and motor number 1281 is missing out of sequential motor numbers, range of 1257 - 1309, accepted in other D.VIIF's)

BMW Nr.1301 DVIIF 4275/18 Accepted July 19th
BMW Nr.1301 D.VIIF 4434/18 Accepted August 21st
BMW Nr.1301 D.VIIF 5136/18 Accepted September 21st

BMW Nr.1309 DVIIF 4285/18 Accepted July 19th
BMW Nr.1309 D.VIIF 4431/18 Accepted August 21st
BMW Nr.1309 D.VIIF 5120/18 Accepted September 24th

BMW Nr.1319 DVIIF 4298/18 Accepted July 19th
BMW Nr.1319 D.VIIF 5051/18 Accepted August 21st

BMW Nr.1329 DVIIF 4373/18 Accepted August 17th
BMW Nr.1329 D.VIIF 5137/18 Accepted September 30th

BMW Nr.1337 DVIIF 4331/18 Accepted July 23rd
BMW Nr.1337 D.VII 484/18F Accepted July 30th

BMW Nr.1342 D.VIIF 4358/18 Accepted August 16th
BMW Nr.1342 D.VIIF 5131/18 Accepted September 17th

BMW Nr.1346 D.VIIF 4360/18 Accepted August 17th
BMW Nr.1346 D.VIIF 5116/18 Accepted September 26th

BMW Nr.1348 D.VIIF 4371/18 Accepted August 16th
BMW Nr.1348 D.VIIF 5108/18 Accepted September 7th

BMW Nr.1353 D.VIIF 4410/18 Accepted August 21st
BMW Nr.1353 D.VIIF 5127/18 Accepted September 9th

BMW Nr.1354 D.VIIF 4390/18 Accepted August 21st
BMW Nr.1354 D.VIIF 5119/18 Accepted September 12th

BMW Nr.1359 D.VIIF 4429/18 Accepted August 20th
BMW Nr.1359 D.VIIF 5117/18 Accepted September 4th
BMW Nr.1359 D.VIIF 7710/18 Accepted October 8th

BMW Nr.1363 D.VIIF 4439/18 Accepted August 21st
BMW Nr.1363 D.VIIF 5135/18 Accepted September 25th

BMW Nr.1365 D.VIIF 4367/18 Accepted August 17th
BMW Nr.1365 D.VIIF 5109/18 Accepted September 12th

BMW Nr.1369 D.VIIF 4420/18 Accepted September 2nd
BMW Nr.1369 D.VIIF 7629/18 Accepted September 28th

BMW Nr.1370 D.VIIF 4441/18 Accepted September 2nd
BMW Nr.1370 D.VIIF 7610/18 Accepted October 8th

BMW Nr.1372 D.VIIF 4432/18 Accepted September 2nd
BMW Nr.1372 D.VIIF 7609/18 Accepted September 18th

BMW Nr.1373 D.VIIF 4443/18 Accepted August 21st
BMW Nr.1373 D.VIIF 5125/18 Accepted September 11th

BMW Nr.1376 D.VIIF 4426/18 Accepted September 7th
BMW Nr.1376 D.VIIF 4433/18 Accepted August 30th

BMW Nr.1380 D.VIIF 4407/18 Accepted August 16th
BMW Nr.1380 D.VIIF 5115/18 Accepted October 2nd

BMW Nr.1408 D.VIIF 5065/18 Accepted September 6th
BMW Nr.1408 D.VIIF 5148/18 Accepted October 17th

BMW Nr.1411 D.VIIF 5064/18 Accepted September 6th
BMW Nr.1411 D.VIIF 7635/18 Accepted September 27th

BMW Nr.1420 D.VIIF 5097/18 Accepted September 5th
BMW Nr.1420 D.VIIF 7618/18 Accepted September 18th

Sorry to post all of them, but I like to show raw source data so other may make their own conclusions I may miss, and/or they may use it for some other insight to another Fokker riddle.

I don't see any trends, like a batch of recovered BMW motors going to Fokker and being accepted on the same date, but I guess things do get blurry when you try to put it down to exact dates...that's too restricting.

We have 27 instances of Fokker re-installing a BMW out of 247 total BMW acceptances, (not including Opel built BMW's, none of which were re-installed). That shows about a 12% rate, is that enough to show any trend of motors being shipped back to Fokker because they were "his"?

There are around 14 instances of Mercedes motors being shipped back to Fokker and were re-installed out of approximately 556 Mercedes total acceptances. That's about 2%, much less than the BMW, so there may be a possibility?? It can be said that Mercedes motors were readily available as compared to the BMW's, so there would be much less a likelyhood for them to be re-cycled back to Fokker in the first place.

The bottom line is Fokker was getting BMW motors back from salvaged aircraft!

One may try to make the statement that the "F" was simply to make the distinction between the BMW and Mercedes powered aircraft to aid field commanders to group alike aircraft together for optimum attack. I think thin ice on that one. We have the letters from Goring when he was commander crying about the shortage of "F" D.VII's, and the mismatch of D.VII's when trying to attack. He certainly knew what a D.VII "F" was, he just couldn't get enough of them!

Best wishes,
Dave W.

dirtyshirt · 7 November 2009, 10:01 AM

Good evening Dave.
Thats one hell of an interesting post.
A 12% return rate on BMW engines versus a 2% return rate on Mercedes. No auditor would accept these figures without querying them.
Is it possible that Anthony Fokker had a financial inducement to deliver BMW engined D.VII's. I wonder if there is any record of any of the original D.VII's as delivered with BMW's continueing on in service but powered with Mercedes engines.
That sequence of deliveries and returns deserves probing.
Regards
Mike.

Dan_San_Abbott · 7 November 2009, 07:41 PM

Hi Dave:
The date of acceptance is the date the Bau Nr.13 at Fokker Flugzeugwerke had accepted the aircraft after a test flight and thorough inspection at Schwerin in Meckenberg. At this point it may et there several days before the Army personnel have disassembled the machine and loaded on a flat bed railway car. It could be a week before the train is made up and transported to the Armee Flugpark. There it had to be unloaded, moved to the hangars, inspected for transit damage and re-assembled, test flown and picked by the pilots from the assigned assigned Jasta. This process could be not less than two weeks and as much as three weeks before the machine is at the assigned Jasta. Idflieg assigned the aircraft to a specific Jasta by way of the Armee Flugpark. Dave, I tend to be conservative with assigments.
Blue skies Dave,
Dan-San

Dave_Watts · 8 November 2009, 03:34 PM

Sorry duplicate entry

Dave_Watts · 8 November 2009, 03:37 PM

Hi all,

Thanks Mike, you right, more probing could be done.

Dan-San, in a around about way you nudged me back in line on the "later" acceptances, (May 15th), not being capable of making it to the front by "May 20 - 26th. Well taken. I was just wondering where you pulled the serial numbers of "231/18 - 245/18" from? I figured you pulled it from the photos. Just to nudge you back

you should drop 231/18F from your range as we know it resided back with Fokker to be used in the next two figther competitions.

Anyone to chime in on the "F" designation riddle? There is nothing against speculation.

Best,
Dave W.

Laserlloyd · 8 November 2009, 04:26 PM

I had compared the number of days that it took between the acceptance date to that dispatched date on the Dr.I's and found that it varied a lot.

Only a hand full took less then 7 days before they were dispatched.
The next grouping would take 10-16 days before they were dispatched.
Then the next group would take 20-26 days before they were dispatched.

During the grounding of the Dr.I's it took about 42-44 days days before they were dispatched, this is to be expected.

Now I only have a few of the delivery dates for October 20th delivery that took only 7-10 days to transported to the Armee Flugpark, unloaded, rebuilt, test flown (?) the picked up by the assigned Jasta.

I only bring this up to what was happening on the delivery's up to around January of 1918. Since we don't have (or should I say I don't have) the dispatched dates for the missing months I speculate that it would take about the same number of days for the D.VII's too.

Dave, do you know if Peter Grosz had anything on the "F" (BMW motor) reference not to mention Taz or Greg.

BTW, great thread...

Lloyd...