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

[Kurfürst]

Originally Posted by Glider

The Pilots notes that Kurfurst quotes from isn't from the BOB. Unless he agrees that Spit II in the BOB had 2 x 20mm and 4 x LMG which we know didn't happen

... and now you are making things up again.

[Glider]

Originally Posted by Kurfürst

... and now you are making things up again.

We have been throught this before on another Forum and again on this forum

The Zeno pilots notes you quote are here
http://www.zenoswarbirdvideos.com/Im...pit2Manual.pdf

Please note item 35 gun controls where it has a) and b) and B has 2 x 20mm and 4 x LMG. Section 2 has the bit you keep quoting 100 Octane and 87 Octane.

The posting where you identified these as being the ones you quote is here
http://www.ww2aircraft.net/forum/avi...a-20108-8.html

The Pilots Note I refer to are here
http://www.ww2aircraft.net/forum/oth...uals-9050.html

Please note item 44 Gun Controls where only the 8 mgs are mentioned, and item 55 where it clearly states only 100 Octane

The question I ask is this:-
When you know with an absolute certainty, that the quote you are making is wrong and misleading, why do you keep mentioning it as part of your evidence?
Unless of course you believe it to be true and that the RAF had Mk II spits in July 1940 with 2 x 20mm and 4 x LMG which is what your pilots notes say

People are free to look at these links, and if you do not reply with an explanation may well make their own mind up as to why.

[Kurfürst]

Originally Posted by Glider

The question I ask is this:-
When you know with an absolute certainty, that the quote you are making is wrong and misleading, why do you keep mentioning it as part of your evidence?

What I know with an absolute certainty is that there is a Spitfire I manual and a Spitfire II manual, both from June-July 1940 and both specify both 87 octane and 100 octane limits.

I also know for certainty that you have an idiotic thesis why to dismiss yet another source which is clearly dated June 1940 and notes what limits apply 'when 100 octane fuel is used' and not 87.

Guess what, I just do not give credit to neither this idiotic thesis of yours, neither the other which says that when British papers say select fighter squadrons, it's 'a typo', nor the one which says its not a typo but it was reveresed later, nor the one which says the only 100 octane fuel the Germans had was from captured British stock, nor the one which says that no Spitfire or Hurricane had two pitch propeller in the Battle of Britain and so on.

Guess what, you simply have no credibility left in my eye.

Unless of course you believe it to be true and that the RAF had Mk II spits in July 1940 with 2 x 20mm and 4 x LMG which is what your pilots notes say.

Of course they had. Look up Spitfire the history, on page 60 in my edition :

"P9504... still had four of the original Browning MG mountings in the wings. It was used to test a trial installation of two Hispano cannon and four Browning guns... within days a second Spitfire, X4257 had a wing built from scratch, with the new armament and service trials begun on 20 August. Five days later R6761, 6770,6889,6904 and 6919 were withdrawn from No.19 and modified to the same standards. etc.."

P9504 was a Mark I, the first produced a/c with 4 x 7.7 + 2 x 20mm, first flight 30 April 1940.

People are free to look at these links, and if you do not reply with an explanation may well make their own mind up as to why.

Boooh, more childish threats reminding me of dire consequences. Had it crossed your mind that I usually do not reply to your posts because I find them a waste of time, being illogical, wishful and of no consequence, clinging fanatically to an idea you cannot prove at all?

How about just taking Crumpp's advice which seem to be the majority view here anyway - admitting that we (you) simply do not know the exact details (yet) and have really no solid idea how many Squadrons were employing 100 octane fuel?

[Glider]

Originally Posted by Kurfürst

Had it crossed your mind that I usually do not reply to your posts because I find them a waste of time, being illogical, wishful and of no consequence, clinging fanatically to an idea you cannot prove at all?

I admit to thinking that as all I normally ask you to do, is supply some evidence to support your case, that your lack of reply is because you don't have any evidence to give.

Re the layout of the pilots notes, people are free to look at a selection and make their own mind as to which has the correct format.

They may also wonder how you have pilots notes for the Spit IIb with 20mm (including photos of the cockpit) in July 1940, for an aircraft that wasn't built until 1941 and believe that to be solid proof.

[41Sqn_Banks]

Originally Posted by Glider

Re the layout of the pilots notes, people are free to look at a selection and make their own mind as to which has the correct format.

I did check "AP 1565B Vol. I" ("Vol. I" is the full manual; the "Pilot's Notes" are only Section 1 and 2 of this manual).

Section 2 starts with Para 1 "Handling and Flying Notes for Pilots" on page "F.S/3". This is the one posted by Kurfürst, that contains engine limits for 100 and 87 octane fuel. This page is amended by Amendment List 31, I don't have a date for this list but A.L. 30 was issued December, 1943.

At the end in Para 55 of Section 2 there is the unamended page "F.S./16" that contains only limits for 100 octane fuel.

The "List of Contents" (dated June, 1940) confirms that Para 55 contains the "Notes concerning the Merlin XII engine", however Para 1 should actually contain an "Introduction" and not "Handling and Flying Notes for Pilots", which obviously was added later. The unamended Para 1 can be seen in this copy here: http://www.scribd.com/doc/4598146/Pi...lin-XII-Engine

[41Sqn_Banks]

Section 4 "Instructions and Notes for Ground Personnel" mentions in Para 4

The fuel ... to be used with the Merlin XII engine are as follows:-
Fuel .............. 100 Octane

Section 8 "Engine Installation" was issued August, 1940 with A.L. No. 3 in Para 14 "Fuel System"

The fuel system ... uses 100 octane fuel ...

The use of 87 Octane fuel is not mentioned in these sections.

It's obvious that the guidelines for the use of 87 Octane fuel were not contained in the initial issue of June 1940 and were added later.

[lane]

Interestingly, at the time of the March 1939 planning memo calling for 100 octane to be brought into use by 16 squadrons, 15 squadrons were operational with Spitfires or Hurricanes, with 3 others in the process of forming or converting. The units are as follows:

Mar-39
Sqdn Base Aircraft
1 Tangmere Hurricane
19 Duxford Spitfire
32 Biggin Hill Hurricane
41 Catterick Spitfire
43 Tangmere Hurricane
46 Digby Hurricane Converting from Gauntlets March 39
54 Hornchurch Spitfire Converting from Gladiator March 39
56 North Weald Hurricane
66 Duxford Spitfire
73 Digby Hurricane
74 Hornchurch Spitfire
79 Biggin Hill Hurricane
85 Debden Hurricane
87 Debden Hurricane
111 Northolt Hurricane
151 North Weald Hurricane
213 Wittering Hurricane
501 Filton Hurricane Forming with Hurricanes in March 39

The status of other squadrons that had not converted to Hurricane or Spitfire by March 1939 but had converted by December 1939, when the stations at which they were based in December 1939 were required to be supplied with 100 octane, were as follows:

3 Kenley Gladiator
17 Kenley Gauntlet
65 Church Fenton Blenheim
72 Church Fenton Gladiator
152 not formed none
504 Hucknall Gauntlet
602 Abbotsinch Gauntlet
603 Turnhouse Gladiator
607 Usworth Gladiator
609 Yeadon Gladiator
610 Wittering Hind
611 Speke Hind
615 Kenley Gauntlet
616 Kenley Gauntlet

The 100 octane approval memo from 24 September 1938 suggests that the impetus for converting to 100 octane pre-war was for improved take-off performance, given the propellers that the aircraft were equipped with at that time.

[Kurfürst]

Originally Posted by 41Sqn_Banks

I did check "AP 1565B Vol. I" ("Vol. I" is the full manual; the "Pilot's Notes" are only Section 1 and 2 of this manual).

Section 2 starts with Para 1 "Handling and Flying Notes for Pilots" on page "F.S/3". This is the one posted by Kurfürst, that contains engine limits for 100 and 87 octane fuel. This page is amended by Amendment List 31, I don't have a date for this list but A.L. 30 was issued December, 1943.

Interesting. Do you what was changed with A.L. 31?

At the end in Para 55 of Section 2 there is the unamended page "F.S./16" that contains only limits for 100 octane fuel.

Another interesting point that it appears that +12 lbs was banned at that time for combat use ("5 min all out level"), the maximum allowed was +9, with +12 was only cleared for take off purposes up to 1000 feet. It appears that +12 was not cleared for combat use during the Battle of Britain, and was added only later.

If that's correct, our Spitfire II is running well above (having +12 performance) the established limits applicable (+9 lbs boost) and having a performance not representative for the Battle of Britain period.

With it's historical +9 lbs limitation the Spitfire II was capable of about 290 mph at SL. Ours do well over 300 mph. If Bank's findings are correct, this should be corrected to historical levels.

One does wonder though about what was the point about the Spitfire II, given that at it's historical limit of +9 lbs and 100 octane it was only equal in speed to the Spitfire Mk I on 87 octane fuel and inferior to the Bf 109E on 87 octane fuel (not to mention 96 octane C-3 fuelled variants).

The "List of Contents" (dated June, 1940) confirms that Para 55 contains the "Notes concerning the Merlin XII engine", however Para 1 should actually contain an "Introduction" and not "Handling and Flying Notes for Pilots", which obviously was added later. The unamended Para 1 can be seen in this copy here: http://www.scribd.com/doc/4598146/Pi...lin-XII-Engine

This seem to confirm that the unamended Pilot's notes from June 1940 was already referring the Spitfire IIA and IIB types, so Glider's assumption that the mention of cannon armament refers to a later date manual is clearly wrong.

[Glider]

All
I believe that a lot of frustration is being expressed and think it would be a good time to stand back, look at the overall picture and let people decide the strength of the two sides of the argument. This is best done by showing all the relevant papers in the time line so everyone can see how they fit together.

Before I start I will confirm my view that all of Fighter Command was effectively supplied with 100 Octane Fuel for the BOB, that the case is a strong one, but not, a perfect one. However all the following are supported by original documentation from the NA or from published works

16th March 1939 Meeting
Held to consider the question when 100 Octane Fuel should be brought into use in the RAF and the number and type of squadrons involved.

There are three main parts to this.
i) It is true that at this meeting authorisation was given for 16 fighter squadrons and two twin engined bomber squadrons be converted to be use 100 Octane fuel by September 1940. The change over to start at the end of 1939 and the ACAS would select the squadrons.
ii) It was anticipated that these units would use 10,000 tons of fuel over a twelve month period and this would slow down the aim of achieving an 800,000 ton reserve.
iii) The AMPD asked that he should be kept informed as to the progress of the production of the 100 Octane fuel in order that the change over of squadrons could be kept under review in the light of any acceleration or diminution in Supplies.

General Points
- Clearly this is a peace time plan, the war hadn’t started, 18 squadrons would use a lot more than 10,000 tons over twelve months when at war. It is certain that when war started there would be changes.
- It covers both fighters and bombers
- They were not defined as being Blenheim just twin engined bombers of which the RAF had a number of types.
- The 18 squadrons wasn’t a fixed number, it was open to change.

14th November 1939 letter Supplied by Kurfurst
The tests of 100 Octane in the Hurricane and Merlin
In this letter it mentions:-
i) That the tests were successful
ii) It is understood that sufficient stocks of 100 Octane are available
iii) That approval for use in Hurricanes and Spitfires should be given forthwith

7th December 1939 Letter from FC Admin to HQ
This letter starts going into the nuts and bolts of how the change from 87 to 100 Octane would need to be handled. It’s the sort of information any change of this magnitude will need.
The most interesting part is that it lists the 21 operational stations at which the fuel will be required in the first instance. At the time these were all the stations that were equipped or planned to be equipped, with Hurricanes and Spitfires. Also that training units would not be supplied with 100 Octane.

12th December 1939 Letter from Director Of Equipment re Issue of 100 Octane Fuel
Letter confirms that 100 Octane Fuel is approved for use in Spitfire, Hurricane and Defiant aircraft. Issue to be made as soon as the fuel is available at the distribution depots servicing the fighter stations concerned. Some bomber units may be given priority.
The date of use is dependent on when the fuel can be put down in bulk at the distribution sites and the relevant stations. Re the latter as a station empties a tank of 87 Octane it will be replaced with 100 Octane.

Observations
Clearly 7th and 12th papers are a change to the March 1939 notes. Certain aircraft are included and other aircraft in Fighter Command are excluded, no Blenheim fighter units are included or are any Gladiator units.
There is no limit set to the number of squadrons or area such as 11 Group, or any reference to specific squadrons. The RAF decided to use the 100 Octane and instead of limiting it to a number of squadrons, have decided to limit it by type of aircraft. All current and planned Spitfire and Hurricane bases are identified as being in the first instance.
Its worth commenting that Fuel was held at different levels, Strategic Reserves where they were imported, Regional level which is self explanatory, District Level which for FC was depots close to the Sector Stations and those at the individual satellite stations that were supplied from the Sector Stations. The method of distributing 100 Octane was to burn off the supplies of 87 Octane and as the tanks emptied to replace them with 100 Octane fuel. It takes time to use the 87 Octane Fuel in place, to make way for the 100 Octane so there isn’t a schedule roll out, the time will vary from station to station.

February 1940
The first combat reports are being recorded using 100 Octane and stations are also reporting the replacement of 87 Octane with 100 Octane fuel. Clearly the roll out is starting to reach the squadrons and one of the stations we have records for is Drem in Scotland and North Weald in the South of England. Drem is the last place I would change over to 100 octane, if there was a shortage of the fuel

24th February 5th Meeting of the Oil Committee
Request from ACAS that squadrons with Spits, Hurricanes and Blenheim should begin to use 100 Octane., no limitations.
Interesting choice of words as it is clear that some squadrons and bases have already converted and are using 100 Octane. However, there is a change in the replacement process they are discussing how to actively remove 3,600 – 4,000 tons of 87 octane fuel from station storage and replace it with 100 Octane, they are no longer waiting for the 87 Octane to be used up. The pace of change has increased.

6th April 6th Meeting of the Oil Committee
Progress Report on the change.
2 Group Bomber Command making good progress and want to have only 100 Octane on their bases. Agreement reached that four stations would only have 100 Octane and the others five sixths of fuel to be 100 Octane and one sixth 87 Octane.
Confusion in Fighter Command over the changes needed to operate 100 Octane. A Mr Tweedle is tasked with clarifying the situation with Fighter Command
There is also confirmation that the approved storage capacity of 800,000 tons is sufficient and that this tankage will hold between 640-700, 000 tons of fuel allowing for Ullage.
Definition of Ullage - the quantity of wine, liquor, or the like, remaining in a container that has lost part of its contents by evaporation, leakage, or use

18th May 1940 7th Meeting of the Oil Co ordination Committee Summary of Conclusions
The key points here are:-
i) The Committee took note that the position of the use of this fuel in Hurricane and Spitfire aircraft had been made clear to Fighter Command.
ii) Satisfaction was expressed that the units concerned had been stocked with the 100 Octane Fuel
iii) The Minutes were to reflect the appreciation of the work of the Petroleum Board and that the Air Ministry had been impressed with the manner in which the work had been executed.

May 1940 France
There are a number of papers detailing the roll out of 100 Octane to the RAF units in France. These were not in the original list of stations to be equipped and we have similar records for the RAF units sent to Norway.

Squadron Records Post May 1940
A number of RAF squadrons that took part in the BOB formed after May 1940, namely the commonwealth squadrons. None of the records that I have seen for these units mention any change over to 100 Octane and I checked these records until May 1941 by which time they would certainly be using 100 Octane. It’s my belief that this was because the use of 100 Octane after May 1940 was the norm.

1st August 1940 Memo from Downing re the Handling of the Merlin Engine
This note is advising the pilots that there is an increase in engine failures in the overuse of the emergency 12lb boost.
The interesting thing is that this memo was sent to ALL fighter groups. Had we been talking about the 16 squadrons or less this would not have been the case. It would have been sent to the squadrons involved.

7th August 1940
Note confirming that the Use of 100 Octane had been authorised for all Commands.This speaks for itself.


Reserves Information
The following information are the reserve stocks of 100 Octane fuel during the BOB period
This information has come from the War Cabinet Oil Position Monthly report (a) that is available from the National Archives, as well as Gavin Baileys paper(b) and Wood and Dempster(c).

Stocks of 100 Octane
30th September 1939 153,000 tons(b)
27th February 1940 220,000 tons(b)
31st May 1940 294,000 tons(a)
11th July 1940 343,000 tons(b)
31st August 1940 404,000 tons(a)
10th October 1940 424,000 tons(c)
30th November 1940 440,000 tons(a)

Point of interest. From the start of the war until the end of the BOB the reserves never dropped and continued to increase. There was never any danger of the supply of the oil running out, there is no record of any concern over the lack of 100 Octane fuel supplies, in the Air Ministry or the Oil Co ordination Committee, until May 1944.
From September 1939 small quantities of 100 Octane of under 1000 tons were held at Malta and Gibraltar

Consumption Information
The following information are the consumption details of fuel during the BOB period. This information has come from the War Cabinet Oil Position Monthly report that is available from the National Archives.

Consumption of Aviation Spirit
The following figures are for the Air Minstry and are the Average Monthly Consumption

September – November 1939 16,000 tons
Dec 1939 – February 1940 14,000 tons
March 1940 – May 1940 23,000 tons
June 1940 – August 1940 10,000 tons (100 Oct) 26,000 tons (87 Oct)
Sept 1940 – November 1940 15,000 tons (100 Oct) 18,000 tons (87 Oct)

Consumption was running at approx 21% of the Imports

Combat Reports
We have combat reports from over 30 squadrons showing the use of 100 Octane. Its worth mentioning here that the NA have changed access to the combat records. They used to be on microfilm so it was fairly easy to get the combat reports for a squadron and find an example. They are now available on line, but you have to pay to view each record and you cannot view them until you have paid so it becomes a very expensive business with many hundreds of records to look at. A price I cannot afford, but have little doubt that if we were to look at the other squadrons we would find similar records.

Important Note
All the above is supported by original documentation with the exception of my observation on the Squadron Records of Post May, I did look at a number but not all of those squadrons that is a fact but the interpretation is mine alone

[41Sqn_Banks]

Originally Posted by Kurfürst

This seem to confirm that the unamended Pilot's notes from June 1940 was already referring the Spitfire IIA and IIB types, so Glider's assumption that the mention of cannon armament refers to a later date manual is clearly wrong.

Actually it does not. Only the cover states "IIB", but within the text there is only reference to 8 Browning .303 machine guns.

http://www.scribd.com/doc/4598146/Pi...lin-XII-Engine

Introduction Para 7

Eight Browning .303 in. machine guns ...

Section 1 Para 44

The eight guns ...

As this scan is from a post-war (?) reproduction (See copyright on last page) probably used a different cover that contains "IIA" and "IIB".