Inaccurate performance data for BOB fighters in COD comparing to RL data

[Kurfürst]

Originally Posted by csThor

It's most likely II./JG 26 which received the DB 601N-powered aircraft but I am still hesitant to see this type as more than a "candy bar" for the most successful pilots (still too much of a guess rather than knowledge).

Agreed. For the most part of the big daylight battles, the 109s with 601N weren't that numerous to justify the coding required. A 110C-x/N on the other hand is a must IMHO, with roughly half the ZGs were flying, and giving the 110 flying some favour. And it's probably II/JG 26 as you say, though I'd wager that it wasn't handed out to the most successfull pilots of seperate JGs initially. The 19 July memo specifically mentions a Gruppe, plus otherwise logistics and maintaince would be nightmarish, with a mix of 601A and 601N powered Emils...

If I had to choose the line-up, I'd do this:

Bf 109E-1 of 1939, as E-3, but with four MG 17s
[b]Bf 109E-3 (what we have now) of 1939, manual prop pitch, probably no armor(?), 601A. This is pretty much as the 109E started the war in September. A good stand in for May 1940 France battles as well.

Bf 109E-4, 1940. Auto prop pitch, pilot/fuel tank armor in the fuselage. Optionally head/windscreen armor (the latter seems to have been randomly appearing on planes), MG FF/Ms (Mine shells ). Standard DB 601A. 'Boxy' canopy instead of the rounded one. This would represent the detail improvements made in the meantime of September 1939 - May-August 1940, just like the CSP/armor thing on BoB Spitties/Hurris. Plus most E-3 were converted to E-4 by August anyway (the designation was changed because of the MG - FF/M cannon, slightly modified to fire high capacity HE shells).

Bf 109E-7/N. As E-4, but with 601N, and the E-7 can also carry drop tank. Not only it could represent E-7s that started to arrive in August 1940 and become the major production model, it could step-in as the early few E-3/N or E-4/N 'candy bars', as well as older E-1/E-3/E-4 retrofitted with droptanks, and could be well used for later adds ons and scenarios, such as Afrika or Barbarossa, by which time the remaining Emils were typically E-7/Ns beside 109Fs.. I'd skip the basic E-7 entirely, it only differes from the E-4 in the droptank option, and the slightly more powerful (ca +50 HP..) DB 601Aa... needless waste of development time IMHO.

[TheGrunch]

Originally Posted by Kurfürst

Some (two?) Bristol Blenheim Squadrons also seem to have used it.

Was just about to mention this myself, yes.

Thanks for the info above Kurfürst, certainly the fact that the 601N could only use the C3 fuel does simplify matters considerably.

Moggy: Thanks for that info! Now we have to work out what 'operational' means! It's also worth considering whether it's a later edition of the manual, perhaps? It's definitely worth making sure we're 100% on the matter.

[Moggy]

Originally Posted by TheGrunch

Moggy: Thanks for that info! Now we have to work out what 'operational' means! It's also worth considering whether it's a later edition of the manual, perhaps? It's definitely worth making sure we're 100% on the matter.

The Lord giveth, the Lord taketh away. I've just checked the date on the top of Section 2 and it's January 1942.

[Kurfürst]

Originally Posted by TheGrunch

It's a pity the German record situation is not as complete or available.

If you mean German 100 octane (designated C-3) use, indeed the exact units are unclear, but the matter is simplier because in practice it only effects those 109/110 units that were re-engined to the DB 601N.

We know from the transcript of the Generalluftzeugmeister meeting on 19 July 1940 that 1 Gruppe (Wing, usually with 3 Staffeln, or Squadrons. Most likely one of the JG 26 Gruppen, evidenced by the photos) of Bf 109E and 3 Gruppen of 110C had been already converted to 601N. That's roughly 30-40 109s and 100-120 Bf 110s with 601N/C-3 at the time of the start of the Battle.

A fourth 110 Gruppe was converted IIRC in September, so its more of an issue for the 110s, much of them (roughly half) had the 601N, and it was a significant performance boost, with the 601A the 110 did something like 520 kph at altitude, the 601N had better output accross the whole altitude range, so it works out as 550-560 km/h, practically as fast as 109s/Spits, and faster than Hurris.

And the 601N wouldn't take anything else but 100 octane C-3, else they wouldn't fly at all. No headaches here which LW airfield got the fuel and which didn't. As a matter of fact British analysis of captured LW fuel samples shows that C-3 was even found in the tanks of some Ju 88s, but that seems fairly irrelevant, as there would be no performance increase compared to 87 octane, to my best knowledge, with their Jumo engines.

Initially 110s had priority for 601Ns, the 109s got priority and begun receiving/retrofitting them at around October 1940.

As of 1 January 1941 there were 112 109Es of all subtypes and 5 109F-1s, 153 Bf 110C/D/Es around, plus 4 He 111P and 34 Do 215s.

See: http://www.kurfurst.org/Engine/DB60x...asheets_N.html

But then again, I have trouble catching up with frigging Blenheims in the Quick Missions.. even with CEM disabled. So there are far more serious issues to be dealt with, either with the sims bugs, with my flying, or with both.

[winny]

As I said earlier in the thread.. All operational Hurricane, Spitfire and Defiant Squadrons in the RAF had been converted to 100 Octane by May 1940

Taken from Spitfireperformance.com

The use of 100 octane fuel was approved for Spitfire Squadrons by 24 September 1938. Fighter Command noted on 6 December 1938 that Duxford, Debden, Northholt and Digby had received 100 octane fuel. As of December 1938 Nos. 19 and 66 were based at Duxford and were the only RAF units then equipped with Spitfires.

The Air Ministry noted in a memo dated 12 December 1939 that "100 octane fuel is approved for use in Hurricane, Spitfire and Defiant aircraft, and state that issue will be made as soon as the fuel is available in bulk at the distribution depots serving the Fighter Stations concerned." Gavin Bailey concluded that "The actual authorisation to change over to 100-octane came at the end of February 1940 and was made on the basis of the existing reserve and the estimated continuing rate of importation in the rest of the year." As of 31 March 1940 220,000 tons of 100 octane fuel was held in stock.
The Co-ordination of Oil Policy Committee noted in the conclusions of their 18 May 1940 meeting with regard to the "Supply of 100 Octane fuel to Blenheim and Fighter Squadrons" that Spitfire and Hurricane units "had now been stocked with the necessary 100 octane fuel". The Committee recorded that actual consumption of 100 octane for the 2nd Quarter 1940 was 18,100 tons.

Wood and Dempster wrote in their book "The Narrow Margin":

As it turned out, aviation spirit was to prove no worry for the R.A.F. By July 11th, 1940, the day after the Battle of Britain opened, stocks of 100 octane petrol used in the Merlin engine stood at 343,000 tons. On October 10th, twenty-one days before the battle closed, and after 22,000 tons had been issued, stocks had risen to 424,000 tons. With other grades of aviation spirit total stock available on October 10th, 1940, was 666,000 tons. Oil reserves were 34,000 tons.

Wood & Dempster’s "The narrow margin" shows figures for stocks of 100 octane are in agreement with those of the War Cabinet, however, their figure of 22,000 tons issued falls short of the Air Ministry’s figures as shown below.

By 7 August 1940 "authority has been obtained for the use of 100 octane fuel in all operational aircraft and that instructions to that effect are being issued to Commands",

i.e. all operational aircraft in Bomber, Coastal, Training and Fighter Commands.
On October 29, just before the end of the Battle of Britain, 423,400 tons of 100 octane fuel was in stock in the UK. The War Cabinet recorded that 100 octane stocks stood at 202,000 tons on 31 December 1939 and that 100 octane stocks had risen to 499,000 tons one year later on 31 December 1940. The Air Ministry recorded that 58,000 tons of 100 octane were issued during the Battle of Britain. The War Cabinet recorded that 100 octane consumption within the UK for the whole of 1940 amounted to 130,000 tons, an average of 2,500 tons per week. Consumption of 100 octane during the Battle of Britain averaged 10,000 tons per month for the months of July and August rising to 14,000 tons in September followed by 17,000 tons during October. Total consumption of 100 octane fuel during the Battle of Britain therefore was on the order of 50,000 tons.

[TheGrunch]

Originally Posted by winny

The Co-ordination of Oil Policy Committee noted in the conclusions of their 18 May 1940 meeting with regard to the "Supply of 100 Octane fuel to Blenheim and Fighter Squadrons" that Spitfire and Hurricane units "had now been stocked with the necessary 100 octane fuel"[/B]. The Committee recorded that actual consumption of 100 octane for the 2nd Quarter 1940 was 18,100 tons.

As Kurfurst noted in the thread on ww2aircraft.net, that particular "Spitfire and Hurricane units" is an unnecessary alteration made by Mike Williams and it actually says "the Units concerned".
However I think the first quote you posted gets us *most of the way* toward saying that 100 octane was available at all operational units, i.e. "issue will be made as soon as the fuel is available in bulk at the distribution depots serving the Fighter Stations concerned".

[csThor]

The whole story of Emil versions is a total mess since aircraft were retrofitted and changed versions all the time. It was not unusual to have an aircraft delivered as E-1 being refitted as E-4 being refitted as E-7 being refitted as E-7/N. And of course it would only appear as E-1 in official production lists ...

[TomcatViP]

Originally Posted by csThor

The whole story of Emil versions is a total mess since aircraft were retrofitted and changed versions all the time. It was not unusual to have an aircraft delivered as E-1 being refitted as E-4 being refitted as E-7 being refitted as E-7/N. And of course it would only appear as E-1 in official production lists ...

I agree. There was no so much difference in E3-E7. In fact the only true variant could be the E3 with the options added on the field making it a E4 or E7 for historians. When factories added a particular kit it made it a E4/7 but those were more factory tunned.

Jus to add my 2 cents (speaking in € of course) the 601N eng was so only marginaly fitted to the 109 during the BoB that I can see its introduction in CoD just as an AI upgrade for unit commender (what it was in fact).

If anyone could infirm/confirm the following : the E3 Jabo unit might hve been the units lucky enough to get some of those engines.

Anyway dealing with the story of the DB601N, man hve to remind the political aspect of Nazi Germany at war and the influence of key individuals on any strategical assets. Note that this is exactly were the RAF beat the Nazi Luftwaffe and had much more success than France in the fight, not in the 200+lb Spitfire or Hurricane Mark XXX

[winny]

Originally Posted by TheGrunch

As Kurfurst noted in the thread on ww2aircraft.net, that particular "Spitfire and Hurricane units" is an unnecessary alteration made by Mike Williams and it actually says "the Units concerned".
However I think the first quote you posted gets us *most of the way* toward saying that 100 octane was available at all operational units, i.e. "issue will be made as soon as the fuel is available in bulk at the distribution depots serving the Fighter Stations concerned".

I don't really know enough about it! But I do know that there was a conversion involved to the Merlin and that if the fuel was at a certain airfield then some of the aircraft must therefore have been converted (or were in the process of being converted). It wasn't a complicted procedure.

Stocks were ample (given total usage for the battle of 55,000 tons).
so I think it's pretty safe to assume 100 octane to be in use by most if not all RAF frontline fighter sqns by June '40

[TheGrunch]

Haha, don't forget winny, this isn't about what's logical, this is about satisfying Lufwhiners...totally different matter.