Messerschmitt Bf.109 Performance Chronology

[Denniss]

some further issues to fix in the list:
Bf 109E-1 - take-off power was 1100 PS if 1-min rating was available, otherwise 990 PS with 5-min rating
E-3 did not have the 601Aa as standard, this was just an option (for multiple E-series aircraft).
E-7/Z is also called E-7/NZ as it was a subvariant of the E-7N
E-8: No 601E in any 109E, both E-8 and E-9 had 601A/Aa
F-4/Z: 601E engine, the planned F-2/Z with 601N was dropped for this variant
F-4/R1: as F-4 but with provision for underwing guns
G-5 with 605AS engine is a G-5/AS, TO-power was 1435 PS (5-min rating)
G-6/AM - such a designation did not exist. MW-50 introduction possibley in late spring/early summer (I heard of May/June), /U2 machines changed from GM-1 to MW-50 using compressed air from pressurized bottles to feed MW-50 to supercharger (production systems used bleed air). Early production of what-to-become G-14 may have been designated G-6/MW.
G-6/U4: Standard G-6 with MK 108 as engine cannon, /U4 also known in G-10/-14
G-8 - standard engine was 605A
K-4 started with 605DM and was changed to 605DC as soon as it became available, late in war they used ASC, ASB/DB if not DC was on hand.
G-16 - was never built and for sure not with old canopy.

DB 605DB: initially 1850 PS, due to degrades in B4 fuel quality suffered lots of burned-through piston. A change of cylinder firing/ignition sequence cured this but at a cost of 50 PS.
G-10 probably started with 605DM as well and changed to DB once available, other 605D variants fitted as well if no DB on hand

 

[tomo pauk]

I am going to attempt to decipher the new graphs along with the information everyone has supplied. To me it looks like this.
The DB 601N (according to the graph) had the following abilities:
1,175 PS/T.O., 1,255 PS/2,100 m, 1,170 PS/6,900 m. all at 1.35 ata boost.

It is 1175 PS at 4900 m.

The DB 601E in the Bf109F-4 started life with the 1.3 ata boost/2,500 RPM limitation: 1,200 PS/T.O., 1,285 PS/2,100-3,400 m, 1,050 PS/6,000m.

The DB 601E later (NEED DATE) was cleared for 1.42 ata boost/2,700 RPM: 1.350 PS/T.O., 1,440 PS/2,100 m., 1,325 PS/4,800 m.

The data for the 'Steig Kampfleistung' (1.3 ata and 2500 rpm for the DB 601E) need to be read in case the 'Staudruck = 0 kg/cm', ie. when ram air pressure is equal to zero. That means ~1280 PS at ~2100 m, gently falling down to 1200 PS at 4900 m. It was indeed 1050 PS at 6000m.
To the best of my knowledge, the DB 601E was cleared for 1.42 ata and 2700 rpm at turn between 1941 and '42, whether it was December '41 or January '42.

 

[rinkol]

In Adders' book (German Night Fighter Force), there is a statement that the first series of the DB601F (basically a DB 601E with different reduction gear) fitted to the Bf 110 tended to suffer from seized pistons and engine fires and could not be operated at the officially listed maximum boost of 1.3 ata. The book also gives the summer of 1942 as the service entry date for the Bf 110F. The Bf 110F night fighters had the further issue that the flame dampers increased the exhaust back pressure and that this caused exhaust valves to fail after 20 hours of service with the initial design.

 

[CORSNING]

tomo,
Thanks for keeping an eye on me. I was in a hurry.

Jeff

 

[CORSNING]

Denniss,
Thank you for all the excellent information you provided.

Everyone,
Please look over the list in post #1 and let me know if I have missed anything. The only things I could come up with after a quick look: 1. Does anyone have a more exacting date (month) that the Bf 109E-4 became fully operational other than summer 1940?
2. DB 605D PS available?

 

[Denniss]

There were no issues with the DB 601E in the Bf 109F on 30-min rating, the Bf 110F issues are almost all backtraceable to the ineffective flame damper design (unless Mtt made something wrong in the Bf 110 601F engine installation).

 

[GregP]

If you say so Milosh. Not what I've read, but also not worth discussion.

 

[Koopernic]

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.

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

Most Bf109s used B4 fuel. The BMW801 of the Fw190 required C3 fuel. There was about equal numbers of each in Luftwaffe service, late war.

The 2/3rds of production was C3 doesn't make too much sense to me. The DB601/DB605/DB603, Jumo 211 and Jumo 213A all used B4 fuel throughout the war apart from the following exceptions;

DB601N in a short period between the middle of 1940 to the middle 1941 when it was replaced by the DB601E which used B4.
Although DB605ASM and AM were designed for B4+MW50 the apparently used C3+MW50 from about April 1944 till some period in late 1944 when the DB engines again reverted to B4+MW50. The problem apparently being that if the engine ran out of MW50 while in over boost severe engine damage could result. The obvious solution would have been a flow switch in the MW50 line that operates some kind of solenoid, motor or device to cut out the over-boost. I don't fancy the prospects of getting that kind of system working reliably and in production all that easily. One could try a level switch but then we are doing maneuvering, negative G etc. Perhaps the C3 also helped keep the boost up until improved spark plugs came along, but even late war DB605DB were restricted to 1.45 ata when only B4 was available and no MW50.

The main users of C3 fuel was the BMW801D engine of the Fw 190 yet the DB and Jumo engines were much more produced as were there customers Me 109/Me 110/Me 210/Me 410/Ju 88/Ju 87/He 177 while all the transports, Fw 200, used B4.

Perhaps some airfield defense units used C3 in the Fw 190D9/D13 in 1945. We seem to have delivery documents.

The fischer-tropsch.org site has a tremendous amount of information. Most interesting are British intelligence files on analysis of German fuels taken throughout the war from drop tanks, crashed machines, captured fuel supplies etc. Unfortunately they are not indexed but simply pdf image scans taken from microfilm and one has to find a spare 2-3 hours to go through them. There is USAAF and USN analysis but their interrogations didn't begin until after WW2.

These reels show several improvements in C3 fuel grade which they always refer to as "green dyed" fuel. They note a big jump in early 43 which they assume will be for a new type of engine not yet in production that is able to exploit the high rich mixture response. The Jump seems to have been from 94RON/115PN to 97RON/125PN according to the British testing methods, they seem to have reached 97/130 but it has to be noted that allied 100/130 was really 102/130 while 150 was more like 104/150 or 110/150. (The US latter introduced a genuine 115/145)

Unfortunately in many cases they do not bother with a PN test and only do the easier RON test. In most cases they don't even bother with a RON test and simply distill of the fractions, the experienced petro-chemists only testing further if they see something unusual.

The micro film reels were supposed to be destroyed: the US government or US petro chemical industry apparently didn't want useful information about how to synthetically produce gas or coal based gasoline freely available. Fortunately they survived at Texas AM university by accident.

Early 1944 the allies started attacking the German fuel industry, repeatedly, this created severe reductions in production and raised great concerns. C3 fuel was of even greater concern as it required more production facilities and having read plenty of books on the Fw 190D/Ta 152 I can say they all say that the Jumo 213 and DB603 engines were all switched to variants that could use B4+MW50 instead of C3 but note even the methanol for MW50 could be in short supply; synthesis was not too difficult as the catalysts were very precise but it still required a coal gasifier.

Towards the end of the war much German fuel was often just distilled of coke or coal tars (benzol process) due the damage to the synthetic plants. When one says "2/3rds of the fuel was C3" one is referring to greatly reduced production. That 2/3rds of production was C3 before or during 1943 or even early 44 doesn't make sense as there wasn't a German Airforce fleet to use that much C3 fuel.

 

[Shortround6]

The allied fuel specifications are minimums. There are literately hundreds (if not thousands) of possible fuel combinations/blends that can meet a particular fuel specification. Not surprising since something like over 400 different compounds can be found in aviation or motor fuel (not at the same time). Different base stocks do NOT act the same when when blended with different compounds or additives. A simple example is that the addition of lead to straight run gasoline and cat cracked gasoline does not follow the same curve or line of improvement for each CC of lead added.

The Allies had a much larger number of refineries supplying fuel and had to ship it much longer distances and store it for longer periods of time (not all fuel blends tolerated temperature extremes in storage/shipment the same). You weren't as likely to wreck an engine running 102/130 in it as you were running 98/130.

The introduction of commercial 108/135 and both military and commercial 115/145 was to improve cruise power as much as it was to improve peak power (airlines were only interested in getting heavily loaded aircraft off the runway).

 

[stona]

Although DB605ASM and AM were designed for B4+MW50 the apparently used C3+MW50 from about April 1944 till some period in late 1944 when the DB engines again reverted to B4+MW50. The problem apparently being that if the engine ran out of MW50 while in over boost severe engine damage could result.

B4+MW50 was only allowed as an expedient, if necessary, when no C3 fuel was available. The consequences could be more severe than the possibility of severe engine damage. The MW50 Anlage Karte for the G-14 shows this (darf notfalls B-4-Krafstoff geflogen werden) and states clearly that the engine will be immediately destroyed (der Motor sofort zestort wird.) should the MW50 run out.

Steve

 

[tomo pauk]

2. DB 605D PS available?

DB-605DC: 1800 PS (one either C3 only, or on B4 + MW-50), 2000 PS with C3 + MW-50. The letter 'C' in engine's designation should point us that engine was aimed for use of C3 fuel. Link: Kurfürst - DB 601, 603, 605 datasheets - DB 605 DB/DC
As Denniss noted, the 1st examples, called DB-601DB (second 'B' letter was to denote B4 fuel), were to be capable for 1850 PS, but soon were de-rated to 1800.

 

[CORSNING]

Thank you tomo. I looked over wwiiaircraftperformance, Kurfurst and http://109lair.hobbyvista.com/techref/systems/engine/as_vs_d/as_vs_d.htm and made several notes. Once I get them sorted out, I will make the corrections on post #1.

The quick reference sheet is starting to look fairly good.

 

[Juha]

Hello Corsning
for the 605A the 1.42ata Start u. Not power wasn't allowed most of the time up to Oct 43, it was allowed at the beginning of 605A use but banned because of the engine failures, it was again allowed in June 43 and used in Jul 43 but then again banned until Oct 43.

Juha

 

[CORSNING]

Hello Juha,
Thank you for the information. It sent me back to researching.


Everyone,
I have added several changes regarding the DB 601s and DB 605s in post #1. Please look the list over and let me know if I have missed anything. All your help has been greatly appreciated.

Thank you, Jeff

 

[alejandro_]

I have a question on the Bf 109. I will place it here to avoid opening another topic.

What would be the typical version/performance of a Bf 109 at the end of 1943? I was looking at the volumes covering JG53 and all of the losses during this period are G6. The G6AS/G10/G14 with MW-50 came later (April 1944 onwards). I don't think GM-1 was operational in many aircraft either.

The information I have suggests a typical version could be a G6 at 1.3/1.42ATA. AFAIK there are tests for 1.42ATA. Its performance would be close to a G4.

I would appreciate if someone could suggest a test I could use to compare performance with later versions and Allied aircraft that appeared in this period (P-51B, Sptifres with Griffon engines...). A link to wwiiaircraftperformance or kurfurst.org will do.

 

[kettbo]

Alejandro,
The Bf109G-6 would be the main a/c serving. The Bf109G-5 appeared in trickles, FAll of 1943. NO Bf109G-14 until AUG'44. No Bf109G-10 until the Fall.
Prien states GM-1/U2 and MW50/U3 were widely fitted. Sad to say that this is in a paragraph about tall tails in early 1944.
With the Bf109G-6/AS available early 1944, I'm not seeing any Bf109G-5/AS being built earlier.

 

[Denniss]

In the first three months of 44 could could probably cound /AS machines in service with one or two hands (2 converted in jan, 26 in February, 19 in March 44, more facs starting in April 44 though with 168 overall by April 44). /U3 is not MW-50, that's a tactical recon version. Some G-6/MW appeared in summer 44 (AFAIR May/June) , the forerunner of the G-14. No idea when they started rebuilding the /U2 into MW fighters.
Assuming only Erla built G-5 then 230 were delivered by the end of 43

 

[alejandro_]

Many thanks, I will use this test to compare with other aircraft types:

http://www.wwiiaircraftperformance.org/me109/me109g6-combat-emergency.jpg

 

[alejandro_]

Here are the data. I have included a Finnish test with a Bf 109 G-2. Somehow I was expecting the G-14 to be better to G-6 at higher altitude. Is there any G-10 test I can compare with?

The tests I have used can be seen below:

Kurfürst - Finnish Air Force Performance Trials on Messerschmitt Bf 109 G-2, WNr. 14 783 'MT-215'.
http://www.wwiiaircraftperformance.org/me109/me109g6-combat-emergency.jpg
Kurfürst - GL/C-E - Bf 109G-14 / DB 605 AM, Erflogene Werte

 

[tomo pauk]

The G-14 (DB-605AM) should not be able to offer much above 7km vs. the G-6 (DB-605A) since the power gains due to the water-methanol injection were more or less confined for altitudes under that altitude (with ram, that is). Both engines were operating on 1,42 ata on that altitude, the supercharger was not changed for the AM version.
BTW, the '1.70 ata + MW 50' mark is a bit misleading - the MW 50 enabled 1,70 ata

The G-2 should surpass the G-6, on same power setting, on all altitudes. The Finnish tests show far worse performance than the G-2's German graphs (650 km/h max, 2600 rpm and 1,30 ata) and Soviet tests of the same (666 km/h at 7000m, on 2600 rpm and 1,30 ata! and 624 km/h at 10 km)