German C3 fuel production and consumption during 1944-1945?

[bbweiweiw]

Seems to be an intersting thread:

Technical Report 145-45 - The Manufacture of Aviation Gasoline in Germany

The relative volumes of production of the two grades cannot be accurately given, but in the last war years the major volume, perhaps two-thirds (2/3) of this total has the C-3 grade. Every effort was being made toward the end of the war to increase isoparaffin production so that C-3 volume could be increased for fighter plane use.

But just as a "perhaps"......Can anyone give me more information about that? Which was the German aero fuel major volume during 1944-1945,B4 or C3?

Thanks

 

[Kurfürst]

Happy New Year Everyone! Hope you all had a great party! 8)

Well as the US paper says there is no specific figures available, but from impression the stocks (fuel stocks in airfields in Northern Italy and Souther Germany it seems that the ratio of stocks was 50-50%, or perhaps 60-40% for C-3, so it appears that the 'roughly 2/3s of late avgas production was C-3' statement is definietely correct.

What is interesting is that Germans preferred supply their Italian allies with high grade C-3 avgas instead of lower grade B-4 (though both would be suitable for their use) and that some of the German bomber units towards the end of the war was only supplied with C-3; just as curious as the case of why the Italians were supplied with the high grade fuel (C-3 from about 1943 was equivalent 150 grade avgas), as none of the bomber engines actually took advantage of it; certainly not any of the Jumo engines used in late He 111s...

From early 1945 DB notes of meetings it appears that there was a tendency that fighter units in the East relied on B-4, and fighter units in the West relied on C-3, where possible (basically this means Bf 109G/Ks and the FW 190D, which could use either fuel, while the FW 190A/F types always needed C-3).
http://kurfurst.org/Engine/Boostclearances/DB_Niederschrift6730_DB605DBDC_20-1-45.pdf

Kurfrst - OKL, GdJ-Grp. Qu-, Br. B. Nr. 1561/45 g.Kdos. von 20. Mrz 1945.

Basically by the start of 1944 all Bf 109s with methanol boost would use C-3 grade avgas as a rule. The reason for this was probably that in case of failure in the water injection system, C-3 had high enough octane rating to do without knocking, while B-4 would lead to engine damage in this case (though B-4 with methanol water injection allowed the same boost just as fine, so it was probably a safety measure).

The exception being the Bf 109G-10 and K-4 with the DB 605D engine which would need C-3 if they were to use of higher boost pressures; it would appear that they used both fuels. See my findings at :

Kurfrst - OKL, GdJ-Grp. Qu-, Br. B. Nr. 1561/45 g.Kdos. von 20. Mrz 1945.

 

[stona]

I don't know the fuel production figures but I do know that the problem was at least partially solved by producing engines that did not require C3 fuel. The DB605 DB/DC motor was introduced in Nov.'45 and the DB605 ADB/ASC in Dec.'45. Both could run on B4 fuel. Indeed a fuel equipment list of March '45 shows virtually all Bf109 units needing B4 fuel. I'd be more specific if I could find that document!.....it's on this computer,somewhere.
On a lighter note,they certainly didn't want to waste the fuel they had. Note strategically placed buckets.

(From "German fighters over England" Bryan Philpott)

(From "Fighters defending the Reich same author)

Steve

 

[Kurfürst]

Hmm, isn't that draining the fuel from the tanks? IIRC drain valves were at the bottom of the fuselage.

 

[stona]

I believe they are fuelling. There was a rather complex (to me) system of bleeders and overflows which enabled the fuel tanks to be quickly filled. Maybe someone else knows more of the technicalities.
Steve

 

[Glider]

Fag anyone?

 

[Milosh]

I believe they are fuelling. There was a rather complex (to me) system of bleeders and overflows which enabled the fuel tanks to be quickly filled. Maybe someone else knows more of the technicalities.
Steve

Yes Steve. The fill point contained, at least on the 190, the ventilation line, the fill line and the oveflow line.