Spitfire XIV vs Bf-109 K-4 vs La-7 vs Yak-3

[Tante Ju]

Maybe you should read this. You can see units with 109K (IRC kurfurst somewhere in article gave exact numbers, but cannot find it.. :/ but sure 109K was very common) and example of planes with C-3 fuel triangle, Allied reports of 109 with C-3 etc. This goes against your doubts of C-3 lack strongly...

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

Yes you are entitled to your opinion. In the meantime, I ask you to post your sources about alleged lack of C-3 and MW-50.

Also the "accurate" figures you quoted for XIV are for prototype and not representative for serial production XIV. Gearing of engine was changed.

BTW anyone seen flight test for serial XIV?

 

[Milosh]

Reichmarschall Göring : This means that with regard to the DB605, it is impossible to predict whether the engine is ever going to be a useful engine.

Eisenlohr : The engineering changes and the available test results reveal that there is a high probability that concerning the question bearings, the worst is behind us and the situation is going to improve, even if it is not going to be a robust engine, but at least one that can be run at maximum output by the frontline units with full justification. The testing at Rechlin proceeded completely well so far. Cuno reported that four weeks are still required for completion.

Reichmarschall Göring :You have the confidence in that can work out?

Eisenlohr : Yes sir.

Reichmarschall Göring : Nallinger, do you still have great confidence in your child?

Nallinger : On the basis of our latest testings we have the absolute confidence in that with the engneering changes I've reported, the engine will be fixed with regard to the bearings and the Startleistung is going to be cleared for use.

Reichmarschall Göring : What do you think, Petersen?

Petersen : I share this conviction and additionally am convinced that in conjunction with the oil centrifuge, the engine is going to be allright with regard to the bearings. That has always been the experience of the past, the maintenance people predicted that the engine is going to fail soon if the oil pressure dropped below a certain figure, below 100 atü. The new 177s with oil centrifuges have worked well so far, and no bearing failures have been suffered, so that I'm able to say: If these measures which I would like to call detail work are added, the oil centrifuge in conjection with the 605, that the bearing story can be considered to have ended.

Reichmarschall Göring : What do you say, Scheibe?

Scheibe : According to the understanding at Junkers, there should actually be no problem fixing the engine with regard to the bearings. If a far-fetched solution is necessary, then - as Nallinger elaborated - the lubrication has to be taken out of the crankshaft, if it's possible to use the example of the Jumo 211 as a reference which runs in the power-boosted forms N and P at virtually the same speeds without bearing problems.

Kurfürst - Transcript of Generalluftzeugmeister meeting on 7th September, 1943.

Unfortunately, it does not say if the bearing problem was actually fixed.

 

[tomo pauk]

Many thanks for input, Milosh.
Many people are swift to point out the issues DB-605A had during some 12 months, claiming the DB-601E/F was better. The same 601E that was not allowed to make Start Notleistung for some 7-8 months, from June 1941- Jan/Feb 1942.

 

[Aozora]

Maybe you should read this. You can see units with 109K (IRC kurfurst somewhere in article gave exact numbers, but cannot find it.. :/ but sure 109K was very common) and example of planes with C-3 fuel triangle, Allied reports of 109 with C-3 etc. This goes against your doubts of C-3 lack strongly...

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

Yes you are entitled to your opinion. In the meantime, I ask you to post your sources about alleged lack of C-3 and MW-50.

Already posted - Caldwell citing orders from Luftwaffenkommando West ordering fighter units to only operate under favourable conditions, 30 October 1944 - no evidence given that these orders were rescinded.
Also from Kurfurst:Kurfrst - Articles - Notes for "Spitfire Mk XIV versus Me 109 G/K A Performance Comparison"

Also attached (also from Kurfurst via Fischer-Tropsch) pdf file on Luftwaffe fuel consumption
Methanol:
Caldwell JG26 War Diary vol 2

DB605

 

[tomo pauk]

I have no doubt the DB 605 was more powerful than the DB601E - Mankau and Petrick made the point that until initial problems with the DB605 were solved the use of emergency power was forbidden, thus limiting the maximum power. Without seeing the relevant power curves for the DB605 v DB601E how are we to know?

'Who are we to know'? Some rhetorycs.
The power curve for the Db-605E is to be found here (1320 PS @ 4,8 km, Notleistung), the power of the DB-605A is here, at 4,8 km giving the same power, but on Steig Kampfleistung. At 6 km the DB-605A gives 1220 PS, same rating, the DB-601E giving 1150, Notleistung.

What is more important - and my question was - in light of the changes made to the 605 design versus the 601, and the general concerns of the RLM over the DB605, how reliable was the DB 605 by the time the K-4 got into service, particularly with the steep decline in build quality/possible sabotage and shortages of important metals? It also needs to be noted that in late October 1944, because of constant attacks on the oil industry, aviation fuels were in short supply, so much so that Luftwaffenkommando West ordered that operations be curtailed:

I'll thank you for the excerpts, but attaching the problems with fuel quality quantity to the way the engine was designed produced ('inherent design flaws' was it?) does not make a good analysis. In the excerpt by Olivier Lefebvre, the fuel low quality was mentioned among culprits, along with spark plug issues (availability of suitable types). You can note in Allied technical reports that their spar plugs (lead fouling) was an issue with engines running at high boost. You can check the reports at Mike Williams' site.

You keep talking about the "general concerns of the RLM over the DB605", without posting the reports that confirm that, more so the reports dated after late 1943. Yes, the M P book says that there were the issues, and that aplies to the time before late 1943. The engine was reliable enough to power the Bf-109 110, even if that was on St Kampf, for a year. Once the issues were fixed, the ban on Notleistung was called off. The proof is in the pudding?

You can read in your own excerpts that many a Fw-190D-9 was capable of 590 km/h. Should we all now start to throw rocks at Jumo-213A?

From the latest excerpts, much of the blame for DB-605A having problems was on Willy's hands.

 

[Aozora]

'Who are we to know'? Some rhetorycs.
The power curve for the Db-605E is to be found here (1320 PS @ 4,8 km, Notleistung), the power of the DB-605A is here, at 4,8 km giving the same power, but on Steig Kampfleistung. At 6 km the DB-605A gives 1220 PS, same rating, the DB-601E giving 1150, Notleistung.



I'll thank you for the excerpts, but attaching the problems with fuel quality quantity to the way the engine was designed produced ('inherent design flaws' was it?) does not make a good analysis. In the excerpt by Olivier Lefebvre, the fuel low quality was mentioned among culprits, along with spark plug issues (availability of suitable types). You can note in Allied technical reports that their spar plugs (lead fouling) was an issue with engines running at high boost. You can check the reports at Mike Williams' site.

You can read in your own excerpts that many a Fw-190D-9 was capable of 590 km/h. Should we all now start to throw rocks at Jumo-213A?

And where are the DB605 DB/DC power curves? At least I am making the effort to provide supporting evidence, which, so far, has not been properly refuted.

 

[tomo pauk]

The tables are here and here, just a few clicks away from the DB-605A, along with DB-605AM/AS/ASM data.

 

[Aozora]

The tables are here and here, just a few clicks away from the DB-605A, along with DB-605AM/AS/ASM data.

Thanks for that. 8)

 

[Aozora]

Maybe you should read this. You can see units with 109K (IRC kurfurst somewhere in article gave exact numbers, but cannot find it.. :/ but sure 109K was very common) and example of planes with C-3 fuel triangle, Allied reports of 109 with C-3 etc. This goes against your doubts of C-3 lack strongly...

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

Yes you are entitled to your opinion. In the meantime, I ask you to post your sources about alleged lack of C-3 and MW-50.

Also the "accurate" figures you quoted for XIV are for prototype and not representative for serial production XIV. Gearing of engine was changed.

BTW anyone seen flight test for serial XIV?

I can find photos of K-4s with 87 fuel triangles:

(from Prien and Rodeike Bf 109 F,G K Series, 1995 and Wołowski Bf 109 Late versions, 2010 resp.) And, of course, the DB 605DB/DC could be easily switched from one fuel type to another, so having a C-3 triangle didn't have mean that there was C3 in the tank. As for the Allied Reports? Proves that there were supplies of C-3 for individual aircraft from June, July 1944 and January 1945; none of them indicates which units the 109s belonged to.

I can also find a March 1945 directive from the Führer's HQ halting production of the 109 and DB605 immediately, because of the fuel situation:

 

[Tante Ju]

I can find photos of K-4s with 87 fuel triangles:

I can find K-4s (and G-10, G-14) with 100 octane / C-3 fuel triangles too, but IMHO there is no doubt that both types of fuel was employed. This did not effect G-14s much, since only G-10 and K-4 could take real advantage of high octane fuel.

Also aircraft of JG 3 were not meant to use high boost as per orders on Kurfurst site, so use of B-4 is logical. So they used 1.8ata. If power same on B-4 or C-3 - why use C-3..?

A couple of K-4s with C-3 triangle from Kurfurst site:

Commander of 11./JG 53 (III. Gruppe), Lt. G. Landt, in the cocpit of his Bf 109K-4, Yellow 1, photographed at Kreuzstraße airfield, in April 1945.
The 'C-3' notice instructing the ground crew for filling the aircraft with 'C-3' grade fuel is blurry but visible on the cocpit.
Photograph via Janda-Poruba, Messerschmitt 109K, Camouflage and Markings.

Note. this aircraft belongs to one gruppe cleared for 1.98ata boost and has C-3 fuel triangle.

Fw. K.-H. Böttner in the cocpit of an early Bf 109K-4. Note the C-3 fuel triangle to the right, above the tactical markings.
Photograph via Janda-Poruba, Messerschmitt 109K, Camouflage and Markings.

Bf 109 G-10/U4 "Rosemarie" belonging to II./JG 52, photographed at Neubiberg airfield, 8th May 1945. The aircraft formerly belonged
to II./JG 51. The pilot, Ofw. Richter of 7./JG 52 is relieved having just successfully flown to American captivity. The 100-octane fuel sign
marked on the fuselage is particularly worthy of note.
Photograph via Janda-Poruba, Messerschmitt 109G-10/U4.

The personal Bf 109G-10/U4 of Magg. Visconti, an Italian ace with 26 victories to his name. The C-3 fuel triangle is again visible. The fascist
Italian Air Force, the ANR, was supplied from aviation fuel reserves of the OKL, and the major proportion of the supplies were C-3.
Photograph via Nino Arena.

Allied reports of various 109s with C-3 fuel found in tank.

Manifold pressure gauges of K-4, marked for 1.8 and 2.0 ata.

And, of course, the DB 605DB/DC could be easily switched from one fuel type to another, so having a C-3 triangle didn't have mean that there was C3 in the tank.

By same logic having 87 octane triangle does not mean there was 87 octane in the tank.

Kurfürst posted this a while ago (love google ). It shows that that C-3 was readily available on Bavarian airfields to about to same amount as B-4. Units noted to use high ata were at Bavarian airfields according to Kurfurst post, and practically 80% of them were 109s.

On April 22 1945 Luftwaffenkommando West reported the following fuel stocks on airfields in Bavaria:

B-4 = 350,000 liters
C-3 = 284,000 liters
J-2 = 1,897,000 liters


On April 12, `45, Lw.Kdo. West had 42 FW 190As on-hand (Stab/JG300, II./JG300, Stab/NAGr.13), and 197 Bf 109s, (1./NAGr.13, 2./NAGr.13, 3./NAGr.13, Stab/JG53, II./JG53, III./JG53, IV./JG53, III./JG300, IV./JG300,1./NJG11).

110 of these Bf 109s were from Stab/JG53, II./JG53, III./JG53, IV./JG53.
III/JG 53 and IV/JG 53 had 73 Bf 109s with 75 fighter pilots on hand. These two Gruppe of JG 53 had been cleared for 1.98ata in 21 March 1945 by OKL, Lw.-Führüngstab, Nr. 937/45 gKdos.(op) 20.03.45.

In addition, KG 51 could muster 16 Me 262s, and 1.(F)/100 five Ar234s, and various other types (Ju88/188, Ju87, FW 189, Bf110)

As for the Allied Reports? Proves that there were supplies of C-3 for individual aircraft from June, July 1944 and January 1945; none of them indicates which units the 109s belonged to.

Why this is relevant? 109s were obviously using C-3, as opposed to what you say. You have posted Allied intellgence estimates before, I still cannot figure out what did you wanted to prove with that... such reports are well known to be inaccurate anyway.

I can also find a March 1945 directive from the Führer's HQ halting production of the 109 and DB605 immediately, because of the fuel situation:

Yes it was planned to phase out all piston engined fighters and replace them with TL units (and Ta 152). The March 1945 operational orders found on Kurfurst site note this too, but with more detail. 109 units were practically all to be switched to K-4s, then eventually disband.

It is also known that 109 production continued in March and April, until the factories were overrun.

With the letter from OKL - General of Fighters - Gruppe Qu. on 20th March 1945 it was decided:

OKL, GdJ-Grp. Qu-, Br. B. Nr. 1561/45 g.Kdos.
Luftwaffe Supreme High Command, General of Fighters Group, Qu.-, Br. B. No. 1561/45 Confidental Orders.
Die Entwicklung im Rüststand der Tagjagdverbande stützt sich auf die im Notprogramm festgelegten Standardbaureihen und sieht vor:

Für Bf 109-Verbände : K-4
Für FW 190-Verbända : D-9, D-12 mit Übergang auf Ta 152 H
und C

Mit Anlauf und Einfließen der Ta 152 in FW 190 Gruppen wird für diese Verbände eine baureihenbedingte Rüststandsverbesserung erzielt.

Bf 109-Entwicklung schließt im wesentlichen mit K-4 ab und führt - soweit nicht Auflösung vorgesehen - zwangsläufig zu Umrüstungen der Bf 109 Verbände auf TL. Reinrassigkeit der Geschwader wird vordringlich angestrebt, Kombinierung artgleicher Baureihen sind vorübergehend und nach Maßgabe der Fertigung in Kauf zu nehmen.

The development in the equipment status of day fighter units is based on the standard types laid down in the emergency program and anticipates :

for Bf 109 units : K-4
for FW 190 units : D-9, D-12 with changeover to Ta 152 H
and C

With the arrival of the Ta 152 and it`s assignment to FW 190 Gruppen will result in an improvement in the equipment status of these units.

Bf 109 development will essentially conclude with the K-4 and will inevitably lead to the conversion of Bf 109 units - those not scheduled for disbandment - to jet fighters. Homogeneity of the Geschwader is urgent to be strived for, combination of similar types is temporary and because of the levels of production to be accepted .

Obviously with the jet fighters coming along there was no sense to produce piston engined fighters any more.

Essentially you are trying to argue that because of general fuel supply problems, C-3 was not available to 109 units. But the research done by Kurfurst makes this position very illogical. Ie. you try to argue that we do not know if 109K units had C-3 available, because Allied reports do not say which unit etc.

But then.

1.
Für die Verbande mit Bf 109-Austattung ergab sich dann folgende Rüststandentwicklung :

19. III. / JG 53: Bf 109 K-4 bleibt, 1,98 Ladedruckerhöh. (no change, boost increase to 1.98 ata)
20. IV. / JG 53 Bf 109 K-4 bleibt 1,98 Ladedruckerhöh. (no change, boost increase to 1.98 ata)

2.
On April 22 1945 Luftwaffenkommando West reported the following fuel stocks on airfields in Bavaria:

B-4 = 350,000 liters
C-3 = 284,000 liters
J-2 = 1,897,000 liters

3.

Commander of 11./JG 53 (III. Gruppe), Lt. G. Landt, in the cocpit of his Bf 109K-4, Yellow 1, photographed at Kreuzstraße airfield, in April 1945.
The 'C-3' notice instructing the ground crew for filling the aircraft with 'C-3' grade fuel is blurry but visible on the cocpit.

i.e.

1. Order was made for II. / JG 53 to increase boost to 2000 HP levels
2. C-3 fuel was available at Bavarian airfields where II. / JG 53 was deployed
3. Photo evidence exists of II. / JG 53 aircraft using C-3

And your counter evidence evidence is basically this: "general fuel situation was bad"... yes?

 

[DonL]

I realy get not the intention by Aozora.

We all know that the engines had different performance with B4 or C3 fuel.
We all know that the LW had C3 engines at the frontline (FW 190 BMW 801 and the DB 605 engines with C3 fuel).
We all know that the K4 had different performance with B4 and C3 fuel, nothing is new about this and I can't understand what this have to do with the performance charts of the K4, where this issue is outlined.

What's the intention of this discussion?

 

[Tante Ju]

My thought exactly.. I also do not get this (alleged) 'constructional flaw / general unreliability of DB 605' thing.. tomo pauk already covered the problem with this at no. 365 post.. short: no evidence of such concern after autumn 1943.. so whats the point of this discussion?

 

[Milosh]

Some minutes of a meeting (not the best translation)

1.)Boost 1,8ata with B4 fuel
Reason for the meeting were the problems in "field" and at the serial production facility "Genshagen" because of the "white flame" effect during the use of the Higher output. First it is shown by Hr. Dr. Scherenberg how the "white flame" followed by burned pistons, develop. Because of the results of the engine knocking test the lower quality of the fuel is the main reason for the problems. DB has allready solved the problem with adjusting the ignition timing by 5°(???) . This allowes the use of "Sondernotleistung" and the 1.45 and 1.80ata settings. But because of later ignition , 50PS are lost during the "Sondernotleistung", Where the 1,45 ata setting doesn't lose power. DB although mentions the problems with the bad fit of the valvesitrings or the plug thread , that where reasons for the glow-ignition too. But because of improovments in the production these failurs are said to be canceled.

All agreed and the decision was done, that all engines should get the new ignition time. The lose of power is not so critical. But, because of hints from DB (DaimlerBenz), there should be test flight with 5 planes within all alts, but especially above rated alt, to get knowledge about the power loose above rated alt.

END SHEET ONE

This will be done at II/JG11. It is asked, if the ignition timing can be set on old value
if better fuel quality is back. Answer is delayed till it is for sure that only better fuel is used, and if it is shown, that later ignition does have no influence on the planes perfromance. DB mentions that the later ignition point although is better for the plugs that have a thermal problem at all.
It is mentioned too, that the performance lose will be decrease with increasing engine run time , means with less oil lose. It indicates too, that new engines with less oil usage are better in performance than the ones with at first high usage and the lower usage of oil. From the troop should be taken 1 engine with 15-20h for oil consumption and performance tests to be done in Genshagen. Because the b4 fuel is mostly used in the east, the order for the new ignition point/time should get out asap by…

2.)1.98 boost with c3 fuel the first report shows, that the test with the 1.9, and 1.98 boost had negative results.
Then a telegram from Rechlin was shown (they tested 4 engines) that criticized the clearing of the Sondernotleistung by Gen. Ing. Paul direct from the company to A.Galland bevor sufficient tests were done. Rechlin although defend themselves, that they did NOT give the new boost free for the Troop. (looks like some thought they did). DB on the other hand shows their positive test results for the 1.9 , 1.98 usage. They say, that the clearance for the 1.98 boost was given with the same TAGL (?) (think a kind of order) as the 1.8 ata boost was cleared..both on the same day!.

SHEET THREE

It was then decided (after hearing all the reports) than currently only II/JG11 should test the 1.98 boost and that the 1.9ata engine test should be finished when the engines failed. (so no more test after them). The JG should then only get 1.8 ata engine supplies. Heavy punnishment is threaten when this order is not followed. The 1.98 clearance decission may only come from department 4 of general staff. It is suggested that some recon planes should be equiped with 1.98 boost. Decission was not done. To disburden the current 1.98 and 1.9 engines it is suggested to give them the new ignition time too. So, all engines flowen with the sondernotleistung will Be set to the new ignition point/time.

The JG's in field complain about the plug failurs. Especially in the last time the number of failurs increased. DB reports about improoved plug modells and better quality control e.g. with x-ray controlling. Again DB points out that the cooling of the
109 is insufficient and wishes that the LW will solve this problem asap. This was mentioned by Gen.-Ing Paul and arrangements where done instandly.
DB points out that the performance of the "cell" (fuselage/wings) is extremely bad, and even worser J. It makes no sense to increase the power output of the engine when on the other side the plane quality is decreasing dramatically. Is is reported that a coparison of a 109 with a mustang was arranged for Mr. Sauer, but he failed to come. The result of the comparison was, spoken of produktion quality only, shocking for the 109.

SHEET FOUR

At the end of the meeting, from Mr. Dr. Scherenberg points out that DB allready is testing a boost up to 2.3ata (J). But it can be not juged in any way because of only a low test base at the moment.

 

[Milosh]

Tante Ju, do you know how many flights could be flown with that 264,000 ltr of C3?

710 with 400 ltr
405 with 700 ltr

That is, if no Fw190A/F/Gs took any C3 fuel.

..an extract from Lorant/Goyat "Bataille dans le ciel d'Allemagne" ...(a translation) Please not the date.

At Kleinkarolinenfeld, around ten pilots who no longer had aircraft piled into a truck at dawn on 27 April 1945 in order to drive to the airfield at Bad Wörishofen and take delivery of Messerschmitt 109s fresh out of the factories. Fw. Arnulf Meyer (9. Staffel) never forgot the scenes they witnessed that day:

Rows of Messerschmitt 109s and Focke-Wulf 190s lined up around the airfield perimeter, others out in the open (!) under the odd camouflage net. Teams of oxen in yokes in the midst of all this enabled the aircraft to be moved around without utilizing any manpower or fuel… At least one hundred fighters from the assembly lines were dispersed around the field. The Officer that met us showed us the latest sub-types to be delivered: Focke-Wulfs with in-line engines and in particular the Messerschmitt Bf 109 K, an improved sub-type of our "Gustav" model. There was bustling activity on the field. Aircraft were landing and taking off constantly. There was no airfield protection Rotte in the air. Our surprise was even greater when we were told that thirty brand new aircraft were due to arrive at the depot that day if the necessary pilots to ferry them in could be found. We were presented to the airfield commander who had set up his office in a comfortably appointed wooden shack: a fatherly Major who gave us a pleasant welcome. Of course we wanted to take the Bf 109 Ks… He asked us for our papers indicating our various type ratings but after scrutinizing them, he handed them back with a shake of the head and simply said: "sorry, I can't give you any K-4s. You've only flown the G-10, so take the G-10s!"

We tried to explain to him that whether they were the G or K variant, they were still Messerschmitt 109s and any mods were almost certainly to be of a minor nature, unlikely to impact on the handling qualities of the aircraft. He did not appear particularly convinced by our arguments, but I noted how keenly he eyed us smoking our American cigarettes. These were retrieved from US prisoners and our Spieß always had them in his stocks. As naturally as possible, I offered the Major one of these cigarettes. His face lit up. Just for good measure, I left a barely started packet on his desk. He thanked me and told us that he was going to see what he ''could do". In the minute that followed, more packets of cigarettes changed hands and in this way we soon had authorization to take the Messerschmitt Bf 109 K-4s!

We went to select our Messerschmitts in the company of the line chief, who asked us what our destination airfield was. The fuel crisis had also reached this field. Our aircraft were fueled with enough for thirty minutes flying time, which was largely sufficient to get back to Kleinkarolinenfeld. On the other hand the armament magazines were empty. We were given parachutes and life jackets. Suddenly we saw a car drawing up and out climbed the depot commander. He told us in a voice bereft of emotion that he was not sorry that we were taking the 109 Ks. Then he read the text of a teleprinter message he had just received. The presence of American troops and tanks was reported ten kilometers from Bad Wörishofen and he was ordered to immediately destroy all the aircraft housed on the airfield. The Major explained to us that the 109s were easier to blow up than the 190s, as they carried as standard a delayed-action 3 kg explosive charge in the fuselage housed next to the fuselage fuel tank. We smoked a last cigarette together with the officer. The imminent debacle seemed more of a relief to him than anything else. He had fought during the First World War and had been wounded but was of the opinion that the disaster befalling our country was of a much more serious nature on this occasion. He hoped that we would soon be back among our families and that we would not risk our lives pointlessly. He started up his car and drove off.

My first takeoff in the Bf 109 K held no surprises. The aircraft was poorly trimmed and the compass was not functioning, which meant that I had to follow my comrades blindly. A typical product of our war industry in 1945: the instruments were incorrectly calibrated and there was nothing coming through the oxygen mask. Fortunately our flight level did not exceed 1,000 meters. We all landed without incident at Kleinkarolinenfeld. Happily enough the brakes worked…

 

[parsifal]

so, even though I confess to not knowing a great deal about this, it almost certainly suggest that there were some sort of reliability issue with the DB605 engine when using 1.8 ata or above.

Or am i misreading that material?

 

[Shortround6]

I think there are a number of things going on here.

There are 3 things that can affect the reliability and durability of an engine.

1. Climate conditions and usage. Out of control of the factory (beyond fitting filters), Dust, dirt etc and use/abuse of the engine, Merlins in transport service had an "expected" life around 40-50% higher than fighter engines at the end of the war. The transport engines were not running 25lbs of boost if even 18lbs and had long periods of pretty steady running. Does this mean Merlin fighter engines were unreliable?

2. Design and/or construction flaws. Flaws in the design or the construction as intended by the factory. Arnstrong Siddeley Tigers and G-R 14N engines had problems due to a lack of center bearing. DB 605s changed from ball bearings in places to sleeve or plain bearings, these may take a while to sort out. Early Allison's had problems with a few parts in addition to the early reduction gear.

3. Sub-standard construction or quality control. The engines being built are not being built as the company intended due to poor workers, poor materials supplied or other factors. A problem with late war Japanese engines and apparently late war German engines. Perhaps some Russian engines at times?

The Germans may have got the DB 605 sorted out in 1943? and it may have performed as it was supposedto in 1944 (or most of it) but by late 1944 and for 1945 did the allied bombing cause shortages of any materials or a drop in the quality of materials? Did the labor get less skilled? Was the lubricating oil the same quality in the spring of 1945 that it was in the spring of 1944?

I don't know but I can sure understand how the reliability/durability of the 605 could go down hill in the final months of the war without it being an inherently defective or faulty engine.

 

[riacrato]

Tante Ju, do you know how many flights could be flown with that 264,000 ltr of C3?

710 with 400 ltr
405 with 700 ltr

That is, if no Fw190A/F/Gs took any C3 fuel.

You also can't do a lot of flights with 350,000 litres of B-4. The relation is what counts. I doubt anyone denies an overall fuel shortage within the LW.

 

[Tante Ju]

I doubt the Germans (or anybody for that matter) hoarded all the precious fuel to airfields anyway.. such would only ensure that it would be easy target to enemy raids and an even distribution would only mean that a lot of fuel would be in places where it is not needed so much, while other places would not get their requirement. I suppose there was some central distribution store, in protected underground bunkers, and airfields only contained fuel enough for a week or two operation's requirement..?

As riacrato says, its the relative volumes that is interesting. The C-3/B-4 ratio seems pretty much 50/50.

Personally I doubt that anyone's late war piston engine would be very long lived. About 50 hours realistic TBO seems commonly mentioned for those engines, or even less.

 

[Shortround6]

We have the figures for the Merlin and they are well above that.

American Radials in Pacific were also well above 50 hours. With many flights lasting 4-6 hours ( without picking extreme examples) changing engines every 10 flights or so would be ridiculous. Fighting on the eastern front a 50 hour engine might be good for 20-30 flights ( or more?) and would be less of a logistic burden.

The Americans and British also had fewer, if any real material or alloy shortages. Most western allied engines had longer overhaul times at the end of the war than at the beginning. Allisons were much better at the end that at the beginning. Early Allsion crankshafts were alloy steel but NOT shot peened or nitrided. Both processes were added as the war went along greatly improving crankshaft life.

 

[Denniss]

There was a problem with the DB605DB/DC with 1.8ata caused by deteriorating B4 fuel quality. Thus DB had to change the (ignition) firing order to compensate this at the cost of 50PS (1850 to 1800). The 2ata setting for 2000PS was merely experimental in late 1944 and was in operational testing. Kuffies site should have a document stating the date it was officially cleared for use.