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

[Osprey]

Your first sentence makes no sense to me. But, may I ask why you avoid answering questions which destroy your argument? If you cannot answer without resorting to character assassination then you are defeated.

[klem]

What the hell do Australian Fuel Supplies in 1940 have to do with the Battle of Britain?

Are we seriously to believe that the British Government's reluctance to assist in the supply of 100 octane fuel to Australia, at a time when there was no war in the Australian region, was an indication that they didn't have enough for the RAF in Europe where there was a war raging? "Here you go Australia, we actually need it more than you do at the moment because we're trying to survive but we're nice guys so we'll take a chance ..."

The British 100 octane fuel position in 1940 is explained in many documents, links etc already posted. And if there was any doubt about sufficient supplies for the entire RAF does anyone seriously imagine that the key front line defence units (fighter squadrons) would have had to make do with anything less than the best that was available?

Oh, wait. We've already had that discussion.

I don't care if 87 octane aircraft are modelled as long as 100 octane types are too. Both fuels were available during the BoB. Beyond that, take it up with the mission builders.

[ACE-OF-ACES]

Originally Posted by klem

What the hell do Australian Fuel Supplies in 1940 have to do with the Battle of Britain?

Are we seriously to believe that the British Government's reluctance to assist in the supply of 100 octane fuel to Australia, at a time when there was no war in the Australian region, was an indication that they didn't have enough for the RAF in Europe where there was a war raging? "Here you go Australia, we actually need it more than you do at the moment because we're trying to survive but we're nice guys so we'll take a chance ..."

Exactally

[TomcatViP]

In the series of " What archives tells us" here is the FLIGHT archives that I cited two days ago :

- There was no 100 octane fuel usage during BoB in the FC. Here I am putting my money on British pride that would hve pushed forward any of its usage (ok Brits are not French but never the less )

- in 1941 increased power Merlin's had 9lb boost level

- 100 oct fuel was used by some aircraft in the RN (Fulmar) fitted with special engines such as the Merlin VIII (presumably to compensate for the extra weight of the 2nd crew member and low alt missions)

- In 1941 planes were still using 87 octane such as was the Hurricane with Merlin XX

Sources : (http://www.flightglobal.com/pdfarchi...0-%201286.html)

1. "International power of the Merlin I and II was 950/990 h.p. at
2,600 r.p.m. at 12,250ft, and the maximum take-off output was
890 h.p. at 2,850 r.p.m."

2. Merlin III : "The power output of the standard engine,"
writes Harold Nockolds, "was 1,030 b.h.p. at 3,000 r.p.m. at
10,250ft with plus 6i lb boost. "

3. "the petrol normally used at that time was 87
octane"

4. "The Merlin II and I I I were installed in the Spitfire I, Defiant I,
Hurricane I, Sea Hurricane I, and Battle I, and were—as will
always be remembered—vital factors in the winning of the Battle
of Britain. The Merlin IV had pressure-water cooling in place
of the glycol cooling of the earlier models, and was developed
for installation in the Armstrong Whitworth Whitley IV bomber.
The Mk VIII, installed in the Fairey Fulmar I, was a medium supercharged
unit rated at 1,010 h.p. at 2,850 r.p.m. at 6,750ft,
and, using 100-octane fuel, delivered 1,080 h.p. at 3,000 r.p.m. for
take-off."

5. "The Merlin X—installed in the Halifax I, Wellington II and
Whitley V and VII—represented a very important advance in
that it had a two-speed supercharger to improve take-off, lowaltitude
performance during climb or level flight, and fuel
economy under cruising conditions. The speed change was
effected through an oil-pressure system, the actual changeover
under full power taking about a second. In low gear the Merlin X
gave 1,145 h.p. at 5,250ft, and in high gear 1,010 h.p. at 17,750ft."

6. "The Merlin XII, driving a Rotol three-blade constant-speed
airscrew, was installed in some Spitfire lls ; its maximum output
was 1,150 h.p. at 3,000 r.p.m. at 14,000ft and it had a 0.477:1
reduction gear."

7. "The next production-type engine was the Merlin XX, which,
compared with the X, delivered a greatly increased power at
height." [...] "Thus, using 100-octane fuel,
the international rating in low gear was 1,240 h.p. at 2,850
r.p.m. at 10,000ft and plus 9 lb/sq in boost; in high gear the
figure was 1,175 h.p. at 2,850 r.p.m. at 17,500ft, again at plus
9 lb boost."

8. "The Merlin XX powered the Beaufighter II, Defiant II, Halifax II and V, Hurricane II and IV, and Lancaster I and III."

9. "An increase in take-off output from 1,300 h.p. to 1,600 h.p. characterized
the Merlin 32, which powered the Barracuda II and
Seafire II."

10. "A variant which saw very extensive service was the Merlin 45,
fitted in the Spitfire V, P.R.IV and VII, and Seafire I I ; at 16,000ft
and 2,850 r.p.m. its output was 1,200 h.p. The Merlin 45M was
rated for duty at lower levels and delivered 1,585 h.p. at 2,750ft;
it was fitted in the Spitfire L.F.V"

11. "The Merlin 46 and 47 were
both high-altitude engines (1,115 h.p. at 19,000ft); the 46 powered
the Spitfire V, P.R.IV and VII, and Seafire I, and the 47 (which
had a cabin supercharger) found its application in the Spitfire VI."

12. "The key feature of the Merlin 61 was its two-speed, two-stage
supercharger, with two rotors on a common shaft. The mixture
was compressed by the first stage and was delivered to the inlet of
the second stage, where it was further compressed before being
delivered to the induction pipe. In order to reduce the mixture
temperature to a normal figure, a box-like intercooler was interposed
between the outlet of the second-stage supercharger and
the rear of the cylinder blocks. In a typical Spitfire installation
the intercooler radiator was mounted under the port wing in a duct, which also housed one of the main engine-cooling radiators."

13. "The real significance of the Merlin 61 was that at 40,000ft it
developed double the power given at a much lower altitude by the
Merlin II of 1939/40. Even at 23,500ft its maximum power was
1,390 h.p. The weight had risen to 1,640 lb."

14. The 67 had a reduction gear of 0.42:1 instead of 0.477:1,
as had the 63, 64 and 66, and the 68 was a Packard-built model,
designated V-1650-3 and installed in the Mustang I I I . Its takeoff
output was 1,400 h.p.

15. "The 67 had a reduction gear of 0.42:1 instead of 0.477:1,
as had the 63, 64 and 66, installed in the Mustang I I I . Its takeoff
output was 1,400 h.p. In the Merlin 69—another Packardbuilt
variant, known in America as the V-1650-7—1,490 h.p. was
available for take-off; this engine powered Mustang I l l s and IVs."

16. "The Merlin 130 and 131 were the first of their family to incorporate
downdraught carburettors; and, to eliminate the air scoop
as used on the Mosquito, ducted air intakes were faired into the
leading edges of the wing. The war-time Bendix/Stromberg
carburettor was replaced by a low-pressure fuel-injection system,
which delivered through a spray nozzle into the supercharger eye*.

17. The sum total of improvements incorporated
in these remarkable engines raised the output to 2,030 h.p. at
1,250ft with a boost of plus 25 lb/sq in.

18. Feel free to add your own episode !

*Ivan are your sure of your doc ?

[Osprey]

I don't understand your point Tomcat. Are you seriously arguing the 87 octane case here? I expect it from Kurfurst because he appears to have painted himself into a corner with too much personal pride invested in the argument. But you claim to be a man of education by profession?

@klem, I am a mission builder for our server and it does and will run historical missions only. We have a Luftwaffe faction too, they won't have a problem with it.

[41Sqn_Banks]

Originally Posted by klem

What the hell do Australian Fuel Supplies in 1940 have to do with the Battle of Britain?

Of course there is no connection. However Kurfürst claims that the reason why the infamous Australian document exists is because the Australia Government "rigorously protested" to receive 100 octane fuel from Great Britain in February 1941. It was shown that this was not the case because
a) they didn't intent to switch to 100 octane fuel at that time,
b) they received the requested amount of 100 octane fuel to mix the 90 octane fuel required for the Catalinas and
c) they received the 100 octane fuel directly from Shell and Vacuum Oil Company without negotiation of Great Britain.

[TomcatViP]

@Osprey :

I don't push frwrd the 87 case.

I firmly believe that there was some MkII fitted with improved Merlins. That the improvement was only linked in operational level to fuel is something that I do not believe if we are talking abt 100 octane. But it's only my own opinion.

I also will gladly eat my hat if I am wrong.

Regarding Kurfurst, I hve to say that I dislike the way some are referring to him here. That he deserve it for some past actions... well perhaps you know something that I don't but I do not really like to read some of the comments.

I am not in anyway perfect myself.

~S!

[Al Schlageter]

Originally Posted by TomcatViP

In the series of " What archives tells us" here is the FLIGHT archives that I cited two days ago :

- There was no 100 octane fuel usage during BoB in the FC. Here I am putting my money on British pride that would have pushed forward any of its usage

Are you saying that Flight stated the above?

You would be correct that RAF FC did use 100 octane fuel.

Below is a list of squadrons that I have found references for that used 100 octane fuel.

No. 92 (East India) Squadron pre BoB S
No. 111 Squadron pre BoB H
No. 151 Squadron Feb 1940 H
No. 602 (City of Glasgow) Squadron pre BoB S
No. 609 (West Riding) Squadron pre BoB S

No. 1 (Cawnpore) Squadron May 1940 H
No. 3 Squadron May 1940 H
No. 17 Squadron May 1940 H
No. 19 Squadron May 1940 S
No. 54 Squadron May 1940 S
No. 74 Squadron May 1940 S
No. 56 (Punjab) Squadron May 1940 H
No. 73 Squadron May 1940 H
No. 79 (Madras Presidency) Squadron May 1940 H
No. 85 Squadron May 1940 H
No. 87 (United Provinces) Squadron May 1940 H
No. 229 Squadron May 1940 H

No. 43 (China-British) Squadron June 1940 H
No. 41 Squadron June 1940 S
No. 610 (County of Chester) Squadron June 1940 S
No. 611 (West Lancashire) Squadron June 1940 S

No. 145 Squadron July 1940 H

No. 64 Squadron 5 Aug 1940
No. 65 (East India) Squadron 12 Aug 1940 S
No. 303 Polish Fighter Squadron 9 Sept 1940 H
No. 234 (Madras Presidency) Squadron 18 Aug 1940 S
No. 603 (City of Edinburgh) Squadron 31 Aug 1940 S
No. 616 (South Yorkshire) Squadron 15 Aug 1940 S

No. 66 Squadron 6 Sept 1940 S
No. 152 (Hyderabad) Squadron 4 Sept 1940 S
No. 249 (Gold Coast) Squadron 6 Sept 1940 H

So much for the accuracy of the Flight article. LOL and some say that Lovesey is a Rolls-Rroyce PR lackey.

[Blackdog_kt]

Originally Posted by Osprey

@Kurfurst. I believe you could learn from the "Russells Teapot" argument.

http://en.wikipedia.org/wiki/Russell's_teapot

I'm not interested in the flaky Australian argument anymore since it appears far too unconvincing and more importantly, irrelevant. It matters not even if, as you suggest, that the UK wouldn't give the Australians any 100 octane because they were short. That is not evidence that the RAF didn't have enough to use themselves.

We can use simple logic to decide the truth here. I ask you, do you deny any of these 4 points listed?

1. That the RAF used fuel.
2. Every flight recorded a combat report (provided the pilot returned).
3. That the fuel type or boost to indicate the type was frequently mentioned in combat reports throughout the BoB.
4. That 87 is never ever mentioned and 100 was in every case.

Therefore the entire RAF MUST have used 100 in in combat and no other type. It really is that straightforward. What I do not find straightforward are your reasons for objection. Please, what are they?

Like i said, i want both versions in the sim but ok, i'll bite and play devil's advocate here just for the sake of showing you guys what i get from the whole discussing here. Lets go ahead and take each numbered point one by one, shall we?

1. Correct
2. Correct
3. Correct, the operative word being "frequently". Which could mean it was a differing practice (to be mentioned in the first place) but widespread enough (to be mentioned frequently).
4. Correct. Which could mean 87 wasn't mentioned because it was the default, while 100 was mentioned because for one it was the exception to the rule and secondly, extra boost warranted extra inspections by the mechanics.

I'm not arguing either case, this is just an example to show everyone here how flaky the whole thing appears to an outside observer, no matter which side of the argument one tends to support.

I just think no side has provided any undisputed facts: i see a lot of credible sources in this thread but far too often a lot of them are conflicting, with no real means to discern which i should "believe more". I'm not convinced either way and that's why (as well as the dynamic campaign considerations) i advocate the presence of both types for all aircraft that use higher grade fuel during the BoB.

I remember seeing similar evidence about half the 110 units being also equipped with better fuel and higher rated engines. I want to have both versions, no matter if its a Spit or Hurri or 110. Forgive me when i say that i doubt some of the most invested posters in this thread would do the same, as i have a suspicion that many who support 100 octane Spits would denounce DB601N-equipped 110s and vice versa.

Let's have options is all i'm saying

[Glider]

Originally Posted by Kurfürst

@Glider about post 401.

I am afraid I cannot answer you in detail now due to the lack of time and won't be in the position to do so in the next two weeks.

On the other hand, I do not see any appearance new evidence or even argument in your post, as it only repeats the ones you have been telling us in the last 40 pages of discussion, and probably no undue haste should be spent in addressing these points again.

FYI I have looked over about 1500 pages of 'War Cabinet' and related files at Kew.
I could not find any decision about the alleged full conversion of Fighter Command to 100 octane in the War Cabinet Minutes.

Which tells me that the reason you can't find any reference to 100 octane 'conversion freeze' in the War Cabinet Minutes either is because it was discussed and decided at lower levels, in one of the apprx. 200 War Cabinet commitees - which still are the part of the War Cabinet.

For the number of Committees, please refer to the relevant page of the National Archives website which provides general information about the War Cabinet on the apropos providing 'open access' to the public via digital copies.

You have hit on a key item, I never claimed that the War Cabinet approved or decided on the roll out of 100 Octane fuel. It wasn't their decision.
The point is that this Pips clearly stated that the War Cabinet halted the roll out, that they restarted it later, they didn't it would be in the minutes. This paper if it exists is wrong. If you believe that someone else made the decision find it,, and explain why Pips made such an obvious mistake.

You have stated a number of times that you believe in his paper, that is your choice. I suggest you prove that any statment, he made on any topic on the paper is correct and I do mean any statement, your choice. Something, anything to confirm that any point is correct.

The choice is huge. Take the 25% being converted when the roll out stopped, with 75% of FC using 87 octane you should be able to find something. The Oil Committee who were responsible for the purchase storage and distribution must, if its true, mention it somewhere.