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dogeness

Engine Settings (Manifold Pressure) in Bodenplatte

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Hello all. I would just like to ask if anybody has any idea what the devs are currently planning in regards to maximum M.P./WEP for the various aircraft in Bodeplatte? Does anyone know specifically what M.P. different aircraft will be running? 

 

Examples of some possible settings:

P-51D:  67"Hg, 72"Hg, or 75"Hg

P-47D:  56"Hg, 65"Hg, or 70"Hg

P-38L:  60"Hg or 70"Hg

Bf 109 G -14:  1.42 ata or 1.7 ata

Bf 109 K-4:  1.8 ata or 1.98 ata

FW 190 A-8:  1.58 ata or 1.65 ata

FW 190 D-9:  1.92 ata

Spitfire Mk 9:  +15lb/in2, +18lb/in2, or +25lb/in2

Tempest Mk V:   +12lb/in2

 

These are just some of the settings I know off-hand that these various aircraft ran at different points in time. Does anybody know for certain if the devs will be using any of these settings when Bodenplatte comes out?

 

 

    

Edited by dogeness
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Well, when we know the actual dash numbers ( P-51D-20, P-47D-28, for example) we will have a better idea of the actual power settings that were authorized for use with those particular aircraft. 

Things like P-38, Spitfire, and P-51 tell us very little since all of these aircraft went through any number of iterations during their service life that varied greatly in performance.

Hope this helps-

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4 hours ago, chris455 said:

Well, when we know the actual dash numbers ( P-51D-20, P-47D-28, for example) we will have a better idea of the actual power settings that were authorized for use with those particular aircraft. 

Things like P-38, Spitfire, and P-51 tell us very little since all of these aircraft went through any number of iterations during their service life that varied greatly in performance.

Hope this helps-

Well, we do have the dash numbers for some aircraft (109 G-14, 109 K-4, 190 A-8, 190 D-9, Spit Mk F/L Mk 9,  Tempest Mk V). And, I know for a fact that the P-47D was cleared for 70"Hg and the P-51D was cleared for 75"Hg, both in June 1944. To my knowledge, all D models of the P-51 and P-47 were field-modded to be able to use the new octane fuel to achieve these M.Ps, irrespective of their dash number. Considering the Battle of Bodenplatte started on Jan 1 1945, I would assume those planes should have those settings. The question is, however, whether the devs will give them that or will they consider that too "OP" and only limit the P-51D to 67"Hg and the P-47D to 56"Hg (the settings they used before June 1944).  I also think the P-38L was cleared for 70"Hg in June 1944 as well, so we'll see if it gets that setting in-game, or if they'll just limit it to the measly 60"Hg that it started off with.

 

Edited by dogeness

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6 hours ago, chris455 said:

Well, when we know the actual dash numbers ( P-51D-20, P-47D-28, for example) we will have a better idea of the actual power settings that were authorized for use with those particular aircraft. 

Things like P-38, Spitfire, and P-51 tell us very little since all of these aircraft went through any number of iterations during their service life that varied greatly in performance.

Hope this helps-

No, dash numbers are irrelevant to the engine power setting

Edited by RoflSeal

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Implying that, a P-47D-5 and a P-47D-30 used exactly the same power settings?

Im out of town and away from my reference library at the time. But "irrelevant" seems overly broad here.

As has been stated by others, simply the availability of higher octane fuels (which may not have always been available) allowed more aggressive power settings in dash numbers that were in service as this became available.

S!

Edited by chris455

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The K-4 ran never at 1.98ata in the field for example. That would have required to run MW50 and C3 fuel at the same time which was forbidden. And I dont know about the rest.

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FW 190 A-8:  1.58 ata or 1.65 ata

 

Actually, A8 with emergency power modification runs 1.58 ata at low gear and 1.65 ata at high gear. Since A8 started to get the modification from July 1944, we will definitely see it in BoBP.

 

Sadly, extra HP barely offsets drag and weight caused by additional arm and equipment on A8...... Thus it still has worse performance than current A5.

 

sbjKTLs.jpg

 

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Hey I’m we just talking pistons or we gonna ask about the 262 as well?

 

EGT, fuel burn rates, takeoff and cruise power percentages... emergency procedures, will there be compressor stalls, hot starts, how long will start up take?  Lots of questions for this bird alone :)

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Implying that, a P-47D-5 and a P-47D-30 use exactly the same power settings?

Im out of town and away from my reference library at the time. But "irrelevant" seems overly broad here.

My guess is that in keeping with IL 2 tradition, none of the Schwalbes foibles, ( I.e., flameout on quick accel, etc.) will be modeled. It will sure be a blast just to fly that bird, be sure.

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21 minutes ago, chris455 said:

 

Implying that, a P-47D-5 and a P-47D-30 use exactly the same power settings?

Im out of town and away from my reference library at the time. But "irrelevant" seems overly broad here.

My guess is that in keeping with IL 2 tradition, none of the Schwalbes foibles, ( I.e., flameout on quick accel, etc.) will be modeled. It will sure be a blast just to fly that bird, be sure.

I should be more direct and refer to the P-51D. Obviously the P-47D is wierd because for some reason it didn't get a new designation when it got a bubble canopy ( a major change) and kept advancing the block numbers.

But to answer you, both razorback and and bubble canopy could run on 150 octane if fitted with the -63 engine. Power setting is not a thing that is factored in block numbers.


P-51Ds for example were both fitted with the V-1650-3 and -7 engines (in an unknown proportion, but it was definately done), there is no indication whatsoever in the block number, hell to even say they are different engines is wrong when the 1944 manual says  field conversion kit are available to change it a -3 if required

Edited by RoflSeal

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Roflseal, 

Agree -25 on got the bubbletop, and yes , one could 'retrofit" any dash number with hi- test fuel, but I'm still confused about " Power setting is not factored in block numbers" ( Im sure you meant dash number here).

Late dash numbers often have augmented power settings. Maybe we're thinking about different things ?

Again, Im sitting in a airport in Reno, Nevada and not in my study right now. I have a copy of Allied Aircraft Piston Engines of World War Il I can check when I get home.

Even something as simple as forged pistons vice cast can allow for a higher power setting, and changes like this were common during the developmental period of aero engines during the war. Many of these developments resulted in dash numbers rolling for the aircraft they were installed in.

Just to check for understanding: do you mean that in game dash number differences do not imply a difference in power settings? 

S!

 

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4 hours ago, DerSheriff said:

The K-4 ran never at 1.98ata in the field for example. That would have required to run MW50 and C3 fuel at the same time which was forbidden. And I dont know about the rest.

 

Hmm. Why does this say the opposite though?

EEA2F211-F0AD-4CE2-A326-CFB61B10942A.jpeg

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19 minutes ago, RoflSeal said:

I should be more direct and refer to the P-51D. Obviously the P-47D is wierd because for some reason it didn't get a new designation when it got a bubble canopy 

 And yet, to make that wierder, they gave the P-51B and the P-51C different designations, yet the only difference between those two models is that the B was built in L.A. California, and the C's were built at North Americans new plant in Dallas Texas. That is the ONLY difference in those two Mustang models.

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Well, whatever manifold pressure the US planes will be allowed to have, you can bet they will seize their engines a few seconds after running at that setting.

 

Be very sure.

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15 hours ago, dogeness said:

Well, we do have the dash numbers for some aircraft (109 G-14, 109 K-4, 190 A-8, 190 D-9, Spit Mk F/L Mk 9,  Tempest Mk V). And, I know for a fact that the P-47D was cleared for 70"Hg and the P-51D was cleared for 75"Hg, both in June 1944. To my knowledge, all D models of the P-51 and P-47 were field-modded to be able to use the new octane fuel to achieve these M.Ps, irrespective of their dash number. Considering the Battle of Bodenplatte started on Jan 1 1945, I would assume those planes should have those settings. The question is, however, whether the devs will give them that or will they consider that too "OP" and only limit the P-51D to 67"Hg and the P-47D to 56"Hg (the settings they used before June 1944).  I also think the P-38L was cleared for 70"Hg in June 1944 as well, so we'll see if it gets that setting in-game, or if they'll just limit it to the measly 60"Hg that it started off with.

 

 

As for USAAF airplanes in Battle of Bodenplatte, is it simple -

 

P-47D-25 or higher dash number (I am pretty sure that we will get "Bubble Top") -

WAR EMERGENCY - 64 inHg / 2700 rpm

MILITARY - 52 inHg / 2700 rpm

 

P-51D -

WAR EMERGENCY - 67 inHg / 3000 rpm

MILITARY - 61 inHg / 3000 rpm

 

P-38L -

WAR EMERGENCY - 60 inHg / 3000 rpm

MILITARY - 54 inHg / 3000 rpm

 

All three airplanes were indeed cleared in summer 1944 for higher manifold pressure, however new ratings required 150 Grade fuel and only US 8th Air Force in UK have it. If we are talking about Bodenplatte, we are talking about US 9th Air Force with 100/130 Grade fuel. It make sense to have standard ratings for 100/130 Grade fuel, not for 150 Grade fuel.

---------------------------------------------------------------

EDIT :

11 minutes ago, BlitzPig_EL said:

Well, whatever manifold pressure the US planes will be allowed to have, you can bet they will seize their engines a few seconds after running at that setting.

 

Be very sure.

 

Don't be so salty, ain't gonna happen. In this case there is no gray zone, limits are pretty clear.

Edited by Farky

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2 minutes ago, BlitzPig_EL said:

Well, whatever manifold pressure the US planes will be allowed to have, you can bet they will seize their engines a few seconds after running at that setting.

 

If the Bible Manual says there is a blowup timer, it will be implemented for sure. Btw, what are the blowup timers for these planes? Are there any short timers like 1 minute?

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1 hour ago, VO101Kurfurst said:

 

Hmm. Why does this say the opposite though?

EEA2F211-F0AD-4CE2-A326-CFB61B10942A.jpeg

 

Thanks for the post. I was looking for this everywhere ... Do you know how many units were cleared to use the 1.98 ata?

 

Thanks!

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1 hour ago, BlitzPig_EL said:

Well, whatever manifold pressure the US planes will be allowed to have, you can bet they will seize their engines a few seconds after running at that setting.

 

Be very sure.

 

Nah, once the timers go past 3 mins there is a bit of randomization before engine damage. For 5 min limits which is the US War Emergency Ratings for these planes they can generally go up to around 7 mins or so, at least this is what happens with the other current planes with 5 min timers in game.

 

1 hour ago, Ishtaru said:

 

If the Bible Manual says there is a blowup timer, it will be implemented for sure. Btw, what are the blowup timers for these planes? Are there any short timers like 1 minute?


The US planes have 5 min War Emergency Power manual times. The German planes with MW 50 have 10 min at a time limits.  C-3 without MW 50 would have 5 mins.

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3 hours ago, VO101Kurfurst said:

 

Hmm. Why does this say the opposite though?

 


I would have nothing against 1.98ata in the K-4. But after reading now three times I cant really definatly say that this was actually usable for front line units. It reads more like an arguement between an engineer and the DB(?!). DB said they can use 1,98 while somebody had issues with that.

To summarazie the doc:
Rechlin tests 4 engines with 1.98 ata. the tests fails.
the use of that ata settings is forbidden.
"Unfortunatly" the 1.98ata clearance was send to Frontlinie units before that and (there were issues(??))
an arguement/a investigation starts
Somebody gets criticised  for clearing 1.98 before testing
Somebody is butthurt and says "hey its possible"
1.98ata gets recommended

But in this doc it never gets mentioned if it was cleared after all and was beeing used.


Edit:
 

Ah you forgot to mention the rest of the file:
http://www.spitfireperformance.com/db-minute-6730.pdf

image.thumb.png.113e4e5839c36ba2396b8eb784e80a98.png

 

 

Edited by DerSheriff
edit after reading it the fifth time
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One staffel of JG11 was used as a test unit for a VERY VERY short time. 1.98ata was not cleared for operational use til a few weeks before WW2 ended in Europe. There has been no proof that it was used operationally except for the test unit.

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3 hours ago, Farky said:

 

As for USAAF airplanes in Battle of Bodenplatte, is it simple -

 

P-47D-25 or higher dash number (I am pretty sure that we will get "Bubble Top") -

WAR EMERGENCY - 64 inHg / 2700 rpm

MILITARY - 52 inHg / 2700 rpm

 

P-51D -

WAR EMERGENCY - 67 inHg / 3000 rpm

MILITARY - 61 inHg / 3000 rpm

 

P-38L -

WAR EMERGENCY - 60 inHg / 3000 rpm

MILITARY - 54 inHg / 3000 rpm

 

All three airplanes were indeed cleared in summer 1944 for higher manifold pressure, however new ratings required 150 Grade fuel and only US 8th Air Force in UK have it. If we are talking about Bodenplatte, we are talking about US 9th Air Force with 100/130 Grade fuel. It make sense to have standard ratings for 100/130 Grade fuel, not for 150 Grade fuel.

---------------------------------------------------------------

EDIT :

 

Don't be so salty, ain't gonna happen. In this case there is no gray zone, limits are pretty clear.

Well, that sucks. If that's true, then the P-51D is really gonna struggle against the 109G-14, and K-4.

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2 hours ago, DerSheriff said:

 


I would have nothing against 1.98ata in the K-4. But after reading now three times I cant really definatly say that this was actually usable for front line units. It reads more like an arguement between an engineer and the DB(?!). DB said they can use 1,98 while somebody had issues with that.

To summarazie the doc:
Rechlin tests 4 engines with 1.98 ata. the tests fails.
the use of that ata settings is forbidden.
"Unfortunatly" the 1.98ata clearance was send to Frontlinie units before that and (there were issues(??))
an arguement/a investigation starts
Somebody gets criticised  for clearing 1.98 before testing
Somebody is butthurt and says "hey its possible"
1.98ata gets recommended

But in this doc it never gets mentioned if it was cleared after all and was beeing used.


Edit:
 

Ah you forgot to mention the rest of the file:
http://www.spitfireperformance.com/db-minute-6730.pdf

image.thumb.png.113e4e5839c36ba2396b8eb784e80a98.png

 

 

 

What does the rest say Sheriff? I'm intertested in this topic ...

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4 hours ago, BlitzPig_EL said:

Well, whatever manifold pressure the US planes will be allowed to have, you can bet they will seize their engines a few seconds after running at that setting.

 

Be very sure.

 

You don't know that, so please stop with the rumor-mongering.

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12 hours ago, SCG_Riksen said:

 

Thanks for the post. I was looking for this everywhere ... Do you know how many units were cleared to use the 1.98 ata?

 

Thanks!

 

In the December 44 -January 45, no. We only know that frontline units were issued clearance of the 1,98 ata rating and that engines were set to that rating. ('diese Leistungen direkt der Truppe angeboten wurden und the Motoren umgestellt werden'. ). The document states that the rating was withdrawn around mid/late January 1945, and additional testing was ordered. After some testing by an operational 109 Gruppe or Wing in February 1945 and some modification to the DB setup to cope with the fluctuations in the B-4 fuel's quality, which appears to have been successful, they have cleared the rating again in  March 1945 and ordered the remaining 109 Gruppen in the West to use the 1.98ata rating. 

 

So basically, 1.98ata was used alongside with 1.80 since November - December 1944 till about mid January 1945, when 1.98ata was temporarily recalled and reinstated in March 1945. See below for further details. 

 

 

11 hours ago, DerSheriff said:

 


I would have nothing against 1.98ata in the K-4. But after reading now three times I cant really definatly say that this was actually usable for front line units. It reads more like an arguement between an engineer and the DB(?!). DB said they can use 1,98 while somebody had issues with that.

To summarazie the doc:
Rechlin tests 4 engines with 1.98 ata. the tests fails.
the use of that ata settings is forbidden.
"Unfortunatly" the 1.98ata clearance was send to Frontlinie units before that and (there were issues(??))
an arguement/a investigation starts
Somebody gets criticised  for clearing 1.98 before testing
Somebody is butthurt and says "hey its possible"
1.98ata gets recommended

But in this doc it never gets mentioned if it was cleared after all and was beeing used.

 

 

It very clearly states that the 1,98ata rating was promulgated to the troops and the engines were set up to 1,98ata earlier . The document that states this is dated 24 January 1945 and reflects on past events. You can read the full doc I have quoted here: http://www.kurfurst.org/Engine/Boostclearances/DB_Niederschrift6730_DB605DBDC_20-1-45.pdf

 

There is more to the story of course, since its only a snipped in response to 'never used in the field', which was obviously untrue given the statements in the document and it is clear that during the Bodenplatte / Battle of the Bulge period the rating was cleared and used by frontline units.

 

Now, as the the full story its gets a bit complicated, but there is a trail of documents that make it quite clear. It can be summarized as follows.

 

DB was developing the DB 605D since 1942. It went through many changes, and the model that appeared in 1944 was designated 605D-2, and when provided with MW 50 boost, 605DM.

605DM was an early production version of which relatively few appears to be produced and had different ratings - max. manifold pressure was 1.75 ata and output 1800 PS and was recommended to use C-3 fuel. 30 min Combat ratings were also lower at 1.35 ata. This engine was then discounting in favour of the 605 DB/DC.

 

At around November 1944, the improved DB 605 DB / DC appeared. This one was actually one engine with two setups - DB was for lower boost of 1.8 ata with B-4 87 octane fuel (1.45 ata for 30-min rating), DC setup was 1.98ata and operated on C-3 fuel. The two setups were easily interchangeable requiring only the setting of a screw regulating fuel delivery. 

 

The known Motor Card, or manual for the DB / DC engine, Version C (so it was already the 3rd edition) was issued 1st December 1944 and it mentions the aforementioned two setups for DB (1.8) and DC (1.98) already as cleared. The relevant pages for the these rating can be seen here http://www.kurfurst.org/Engine/DB60x/DB605_datasheets_DB.html and here http://www.kurfurst.org/Engine/DB60x/DB605_datasheets_DC.html.

 

DB 605 DB setup ratings as per the manual issued on 1st December 1944.

 

DB605DB_limits_dec44Motorenkarte.jpg

 

 

DB 605 DC setup ratings as per the (same) manual issued on 1st December 1944.

 

DB605DC_limits_dec44Motorenkarte.jpg

 

The following doc from 20 December 1944 shows the instruction how to mark the engines for the ground crew to know which setting is used in the engines.

When using 1.8ata setup (DB), a large white 'B' was to be painted on the engine housing, and when using the 1.98ata setting, a large white 'C'.

 

Note that 1.98ata and 1.80 ata are both mentioned in this paper as well as alternate setups for the same engine, in line with the aforementioned engine manual of 1st December 1944.

 

KA_MW_im_109.jpg.029a8f1c5f813bde66443cb6e244051d.jpg

 

 

In December 1944 Daimler Benz Genshagen factory run into some assembly problems resulting from oversized pistons delivered by a subcontractor and it also turned out that valve seats and spark plug seats were not secured properly during assembly. The quality of the B-4 fuel delivered also had fluctuations from the standard quality and this have lead to pre-ignition problems with the 605DB setup. There were some problems mention with BERU spark plugs when starting the engine in cold weather. As a result they had some 60 engines failed in the factory, though they have found out the problem with the size of the pistons and assembly of valve and spark plugs seats,  reassembled the problematic engines and run them again without problems. However a number of engines already supplied to testing centres also failed as a result.

 

This is mentioned in the DB internal memo document no. 6642 of 17 January 1945. Rechlin for example reported one engine failing after 30 minutes at 1.98ata (*caugh* *caugh* BoS engine timers) due to a burned through piston, 2 engines had broken connecting rods after 7-12 minutes at 1.98ata and one engine which had run some 40 hours already had supercharger damage after 8 minutes at 1.98ata.

 

Subsequently on a meeting in Berlin (this is the memo I have already posted, no 6730) sh*t hit the fan in the top brass was very pissed off to learn that:

 

'....these Special Emergency Power setting with 1.98 ata on behalf of the Company (i.e. DB) was handed over directly to General Galland, without having a prior extensive testing. He [General Engineer Paul] added extraordinarily sharply, that on behalf of the Technical Office these ratings were given directly to the troops and the engines have been changed to it. DB commented that it had a good testing basis for the clearance at hand and had read up the test results. It was added, that the clearance of 1.98ata has been given at the same time and in the same TAGL [technical instruction] as the clearance of 1.80 ata.'

 

So basically Daimler Benz had some production troubles in December which were rather easily fixed, but coupled with a somewhat burocratic attitude from Luftwaffe engineers and some finger pointing about by whom and how and when engine ratings may be cleared, they decided to withdraw the clearance of 1.98ata in late January 1945 until further troop testing can be conducted. In the beginning of the doc, they mentioned some problems with the 605DB setup (pre-ignition and white flames) which were however caused by a deviation of production B-4 fuel quality from the standard - since the 605DB/DC had very high compression ratio of 8.5:1, it did not tolerate reduced quality fuel very well.  As a result, they have decided to use delayed ignition on the 605DB.

 

The doc 6730 goes on the next page:

 

'After delays in things, it is laid down, that testing of 1.98ata manifold pressure is foreseen to be proceeded with only at the Gruppe 2/11 [this is actually II / JG 11); furthermore the already initiated tests in process with 1.9ata manifold pressure are to be continued, until the said engines fail. The successive replacements for these should be engines with the 1.8ata setup only. Not following these instructions will result in severe punishment. Permission for adjusting for 1.98ata can only be given in cooperation with Department VI. of the General Staff. Apart from the individual men the Chief Engineer has suggested, it is possible to set single fighter-recons with 1.98ata. Decision has not been taken on this yet.Delayed ignition is to be used with engines at 1.9ata and 1.98ata setups, as a result of the termal load that had been observed with them. Therefore all engines, that are flown with the abovementioned Sondernotleistungs, are to be set with delayed ignition.'

 

II. / JG 11 was ordered to do trials of 1.98ata by Umrüstnummer 63253 vom 16.1.1945. II / JG 11 performed the operational trials with 1.98ata and had reported in February 1945 that it had converted 11 of its G-14s, G-10s and K-4s to 1.98 ata (i.e. note that by this time also ASM engines of the G-14/AS had this 1.98ata rating, so basically all 109s with high altitude engines) and had not much trouble with it, with two engines failing in unrelated conditions in normal flight conditions, otherwise the spark plugs were also OK.

 

It is also reported on 4 March 1945 that the modifications were successful and there are no more problems with thermal load of the engine in serial production. BTW it is interesting that they mention that an improved B-4 with an additional 0.16% lead is being tested, and has closely similar quality as C-3.

 

198-040345.thumb.jpg.90b964388c4e56ea9b8d5d21f197ce57.jpg

 

As a result of the testing basis an amendment was produced for the DB 605DB/DC on 1st March 1945 (Reperatur Anweisung, 2. addition, No. 191/345) which stated that due to modifications, the DB 605DB engines can be run even with lowered quality B-4 fuel without danger. These modifications included using delayed ignition (i.e. reduced compression ratio) at 1.8ata which resulted in a power loss of about 50 PS, to about 1800 PS. Since the quality of C-3 used by the DC engines was not effected, no modifications are necessary to the 1.98 ata / DC setup. It also notes that further factory deliveries will be mostly in the DB setup, with the injection pump screw settings displayed how to set up the engine for DC configuration. Basically, you needed to slightly unscrew the regulator for the fuel injection pump to have a DC setup with 1.98ata (and of course adjust the manifold pressure). 

 

Subsequently in 20 March 1945 four G-10/K-4 Gruppen or Wings, I/JG 27, III/JG 27, III/JG 53 and IV/JG 53 operating on the Western front were ordered to change the engine settings to 1.98ata in OKL, GdJ-Grp. Qu-, Br. B. Nr. 1561/45 g.Kdos., see http://www.kurfurst.org/Engine/Boostclearances/605D_clearance198.html . This is most if not all the 109s still operating in the West (as most of the Luftwaffe transferred to the Eastern Front in mid-January 1945).

 

Edited by VO101Kurfurst
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Thanks for the explanation Kurfurst and for taking the time to research and write this in such detail!

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Could be me, but isnt' February/March of '45  somewhat beyond the bodenplatte timeframe?

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Very interesting. Didn't know that to be totally honest. My bad, learned something today. 

46 minutes ago, Sharpe43 said:

Could be me, but isnt' February/March of '45  somewhat beyond the bodenplatte timeframe?

it is. If they just implement 1.8ata nobody can complain. its up to the devs to decide.

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1 hour ago, Sharpe43 said:

Could be me, but isnt' February/March of '45  somewhat beyond the bodenplatte timeframe?

 

if you read Kurfurst Post again you will see that 1.98 ata was used earlier which is at the right time frame for Operation Bodenplatte.

4 hours ago, VO101Kurfurst said:

It very clearly states that the 1,98ata rating was promulgated to the troops and the engines were set up to 1,98ata earlier . The document that states this is dated 24 January 1945 and reflects on past events. You can read the full doc I have quoted here: http://www.kurfurst.org/Engine/Boostclearances/DB_Niederschrift6730_DB605DBDC_20-1-45.pdf

 

Edited by Gunsmith86

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15 minutes ago, Gunsmith86 said:

Could be me, but isnt' February/March of '45  somewhat beyond the bodenplatte timeframe?

 You can't be thinking of this as one day during the Second World War. Obviously, we aren't all going to be running that one missions, over and over again. It's about late '44 to early '45. As a matter of fact, the planeset really covers the airwar all the way to the end. 

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17 hours ago, -=PHX=-SuperEtendard said:

The US planes have 5 min War Emergency Power manual times. The German planes with MW 50 have 10 min at a time limits.  C-3 without MW 50 would have 5 mins.

 

Thank you!

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20 hours ago, chris455 said:

My guess is that in keeping with IL 2 tradition, none of the Schwalbes foibles, ( I.e., flameout on quick accel, etc.) will be modeled. It will sure be a blast just to fly that bird, be sure.

 

Knowing these developers, flameouts and other Jumo-related quirks will definitely be modelled. Given their standards regarding systems complexity (oil viscosity changing as a function of temperature, say) I think they wouldn't allow themselves to look past such a glaring issue. And nor would the Forum Experten. 

Edited by Leaf

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19 hours ago, dogeness said:

Well, that sucks. If that's true, then the P-51D is really gonna struggle against the 109G-14, and K-4.

 

We will see, developers can choose 150 Grade fuel ratings, who knows. Mustangs will be ok against Bf 109s anyway, don't worry.

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19 hours ago, LukeFF said:

 

You don't know that, so please stop with the rumor-mongering.

He might relate to the facts of the Allison of the 40, not many rumours there.

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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.

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- B4/C3 could not be kept for long at this time of war because of lack of additives, Gum appeared quite fast proving troublesome especialy with C3.

 

Oliver Lefevre

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Here's a wild idea: Why couldn't the Devs just make Fuel Octane a choice in loadout screen? They can attach dates of operation to attachments now, so they can make it historically legitimate. And if they can have whole engines as a select-able choice I really don't see different fuel performance as much of a hurdle for the team.

 

 

have a little faith.jpg

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On 4/22/2018 at 8:38 PM, Farky said:

 

We will see, developers can choose 150 Grade fuel ratings, who knows. Mustangs will be ok against Bf 109s anyway, don't worry.

Judging from the DCS K-4, no.

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So no indication of 1.98 being cleared for general operations beyond II/JG 11 testing?

 

That seems to be a far weaker argument than the boost / octane rationale for the late Spitfire IXs, which did use 150 octane and did run at 25lb boost on operations in 1944, but it is not clear whether this was being used as of 1st Jan 1945 in 2nd TAF.

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From what I read above, yes there are indications of it being used. See discussion above (unless im misundertanding something)

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