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

[Glider]

Originally Posted by Kurfürst

Both are from June 1940 IIRC so any later amendments can be ruled out. In addition, Spitfire I pilot notes note 87 octane limits as well. I am haven't seen but its probably true for Hurricanes as well.

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

[NZtyphoon]

Originally Posted by Kurfürst

Quite an unlikely date given that it seems the aircraft on the picture has armored glass and no Spitfires had any armor fitted until about June 1940.

Completely wrong; armoured glass was fitted starting September 1939, as was the extra sheet of alloy over the fuel tank, both of which are clear in the photo.

[Seadog]

Originally Posted by Kurfürst

That leaves with a very well supportable case that half of Fighter Command was operating on 100 octane, and the other half on 87 octane.

Show us evidence of a single operational sortie using 87 octane fuel flown by a front line RAF FC Spitfire or Hurricane squadron during the BofB.

[lane]

Originally Posted by 41Sqn_Banks

The "approved stations" are given in the referenced letter No. F.C. 15447/76/E.Q.2:
http://www.wwiiaircraftperformance.o...0oct-issue.jpg
http://www.wwiiaircraftperformance.o...0oct-issue.jpg

Hi 41Sqn_Banks,

Those 7th December 1939 and 9th December 1939 directives list the stations requiring 100 octane fuel since they had or were expected to have in the near future Merlin engined aircraft. Non operational stations in Fighter command were also required to hold certain quantities of 100 octane.

The squadrons equipped with Hurricanes during December 1939 are as follows: 3, 17, 32, 43, 46, 56, 79, 111, 151, 213, 501, 504, 605.

During December 1939 these Hurricane Squadrons were stationed as follows.
3 – Croydon,
17 – Debden
32 – Biggin Hill
43 – Acklington
46 – Digby
56 – Martlesham Heath
79 – Manston
111 – Drem
151 – North Weald
213 – Wittering
501 – Tangmere
504 – Debden
605 – Tangmere

All these operational stations were listed on the 7th December 1939 or 9th December 1939 as requiring 100 octane fuel, therefore it was Fighter Command's clear intention that these Hurricane squadrons would convert to 100 octane fuel.

The Squadrons equipped with Spitfires in December 1939 are as follows: 19, 41, 54, 65, 66, 72, 74, 152, 602, 603, 609, 610, 611, 616.

During December 1939 these Spitfire Squadrons were stationed as follows:
19 - Duxford
41 - Catterick
54 - Hornchurch
65 - Northholt
66 - Duxford
72 - Drem
74 - Rochford
152 - Acklington
602 - Grangemouth
603 - Turnhouse
609 - Drem
610 - Wittering
611 - Digby
616 – Leconfield

Rochford is the only base not listed on the 7th December 1939 or 9th December 1939 directives, however, 74 Operations Record Book indicates that they had 100 octane while at Rochford in March 1940.

Other units participating in the Battle of Britain that converted to Hurricane, Spitfire or Defiant after December 1939 and the station where they converted are as follows:

64 – Church Fenton
92 – Croyden
145 – Croyden
222 – Duxford
229 – Digby
232 – Sumburgh
234 – Leconfield
242 – Church Fenton
245 – Leconfield
253 – Manston
257 – Hendon
263 – Drem
266 – Sutton Bridge
302 – Leconfield
310 – Duxford
312 – Duxford
601 – Tangmere

Sumburgh is the only base not listed in the 7th December 1939 and 9th December 1939 100 octane Fuel - Issue of directives to receive 100 octane fuel. 232 formed there in July 1940.

Therefore it can be readily seen that the operational stations at which the 100 octane fuel was required were all those stations that held operational Hurricane, Spitfire and Defiant squadrons.

Those units based in France during December 1939 were 1, 73, 85, 87 & 607 in Hurricane and 615 in Gladiator. We know from Post 372 that all these France based Hurricane squadrons were using 100 octane by May 1940.

This listing accounts for the 50 merlin engined Spitfire, Hurricane & Defiant squadrons that fought in the Battle of Britain.

[NZtyphoon]

Originally Posted by Kurfürst

Secondly, about the two letters from December 1939. If we assume that the 24 Stations (if I counted right) listed there are indeed the ones that were said to be selected by ACAS in the March 1939 paper by the end of the year, that leaves a bit of problem, because there were about 60-odd fighter stations operated by Fighter Command in the Battle of Britain...

Wrong again: as of September 1940 there were 19 Sector stations and 23 Satellite aerodromes = 42 bases: * = requiring 100 octane as of December 1939; # = bases not operational in December 1939: NB: 10 Group was not formed until 1 June 1940 http://en.wikipedia.org/wiki/No._10_Group_RAF

Sector Stations:
10 Group: Filton* (listed as operational 9th December 1939), Middle Wallop#

11 Group: Tangmere*, Biggin Hill*, Hornchurch*,
North Weald*, Debden*, Northolt*,
Kenley* listed as non-operational, requiring 100 Octane 7th December 1939#

12 Group: Duxford/ Fowlmere*, Wittering*, Digby*,
Kirton-In-Lindsey, Church Fenton*

13 Group: Usworth, Acklington*, Turnhouse*, Wick and Dyce

Satellite aerodromes

10 Group: Boscombe Down, Colerne, Pembry, Warmwell#,Exeter#

11 Group: Westhampnett*, Croydon*, Gravesend,
Rochford*, Manston*, Hawkinge, Martlesham
Heath*, Hendon*, West Malling#, Stapleford
Tawney#.

12 Group: Coltishall, Turnhill, Leconfield*

13 Group: Catterick*, Drem*, Grangemouth*, Kirkwall, Sumburgh*

http://en.wikipedia.org/wiki/RAF_Fig...of_Battle_1940

attachment: Combat Report Boyd 602 Sqn showing Westhampnett as using 100 octane. August 1940

From the Battle of Britain Then and Now Vol V:

Westhampnett was "...an emergency landing ground for the fighter squadrons based at Tangmere...during the month of July 1940 it gradually assumed the status of a satellite landing ground..." (p. 42.).

Kenley was under a programme of reconstruction and expansion from May - December 1939. (p. 46.)

The following bases had not been established in December 1939:

*West Malling was a private aerodrome and did not become an official RAF station until June 1940. (p.70.)

*Stapleford Tawney did not receive its first operational fighter squadrons until March 1940, when 56 and 151 Sqns used it as a stopover. (p. 184.)

*Duxford and Fowlmere have to be considered together "as the latter had no separate identity..."(p.198.)

*"RAF Station Exeter was officially inaugurated in the presence of Nos. 213 and 87 Squadrons on July 6 1940."(p. 213.)

*Middle Wallop was a training aerodrome until becoming an operational fighter base on 12 July 1940. (p.218.)

*Warmwell was also a training aerodrome and did not become an operational fighter base until July 4 1940. (p. 231.) 609 Sqn was based firstly at Northolt then moved to Middle Wallop on July 4 and used Warmwell as a daytime base.(p.231.) The Spitfire maintenance film was made at Northolt in mid June 1940.

*Filton was later a 10 Group Sector station but only ever hosted one or two squadrons at a time, only one of which - 501 Sqn. - required 100 Octane fuel.

"Squadrons stationed at RAF Filton from the beginning of WW2 included 501 (County of Gloucester) Sqdn (Auxiliary Air Force), now flying Hawker Hurricane I fighters, until 10 May 1940 when that Squadron moved to France; and 263 Squadron (reformed on 20 October 1939 at Filton) taking over some of the Gloster Gladiator I biplane fighters previously with 605 Squadron and still wearing that squadron's code letter (HE). The Squadron went on to Norway in April 1940 operating from a frozen lake.

Between May and July 1940, No. 236 Squadron were based at Filton with Bristol Blenheim twin-engined fighters, flying defensive sweeps over the Channel." (source http://en.wikipedia.org/wiki/RAF_Filton)

In December 1939 there were 36 operational bases, because Fowlmere was an integral part of Duxford.

All of the 6 operational and 1 non-operational 11 Group sector stations were to be provided with 100 octane fuel;

12 Group: 4 out of 5

13 Group: 2 out of 5

10 Group: 1 out of 2

6 out of 8 "satellite' airfields in 11 Group were to be provided with 100 octane fuel;

12 Group: 1 out of 3

13 Group: 4 out of 5

10 Group: 0 out of three

25 out of 36 operational bases were to be provided with 100 Octane fuel starting in December 1939, a ratio of better than 2 to 1.

Far more realistic than 24 out of "60 odd" stations.

[Blakduk]

The evidence keeps mounting up that 100 octane was used throughout fighter command by May 1940.
The case has been proven beyond any reasonable doubt: any jury would have come to that conclusion over 60 pages ago in this thread and any number of other threads in this forum and others.
I joined this debate many months ago with an open mind and have been convinced by the evidence presented and have not seen anything that makes me doubt that conclusion. Until such time as fresh evidence is put forward that any fighter command aircraft were using 87 octane fuel during the Battle of Britain I suggest this thread is closed lest newcomers to the debate stumble upon it and heed the opinion of the tiny minority and believe the matter is being seriously questioned.
When future questions are raised regarding this matter referral can be made back to this thread where all the evidence resides- especially for the developers who seem to have acceded to the minority view that 100 octane was not used routinely in fighter command until late in the BoB.

The only reason this poor excuse for a debate continues is due to a small number of posters who are determined to have the last word and their intransigence in the face of all the evidence. As the old saying goes 'There are none so blind as those that refuse to see'.

[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.

[Kurfürst]

Originally Posted by NZtyphoon

24 out of 36 operational bases were provided with 100 Octane fuel in December 1939, a ratio of 2 to 1.

So its now not even May 1940, not even February 1940, its December 1939 already! That is at least as funny as Glider's dreaming up that there were no two-speed propeller units in BoB!

But of course, you can dream up almost anything and nobody will care.

Far more realistic than 24 out of "60 odd" stations.

No. Its a pipedream as usual, by the same person who stole Morgan and Shacklady's work and published it under his own name on his site, but here tried to discredit them, and now quotes a wiki article as 'proof', the same one he was editing himself. His only source for his pipedreams is his own editing of wikipedia

How much lower can one get I wonder...?

[Kurfürst]

Originally Posted by Robo.

Improved windshields were fitted regardles of the rest of the armor before June 1940.

Hmm - possisble. I would need to check but the May 1940 papers I have (reporting armoring on Hurricane's, but mentioning that no Spitfire have been fitted with armor yet) do seem be in conflict. Perhaps 'improved windshields' were not considered as 'armor' only steel plates?

Out of curiousity, what is your source for armored windshields?

[NZtyphoon]

Originally Posted by TomcatViP

Regarding the armoured windshield I hd the same remark as KF looking at the picture... weird.

The attached photo http://spitfiresite.com/2007/10/earl...on-rauxaf.html is of a Spitfire I of 611 Sqn taken at Digby http://www.611squadronrauxaf.co.uk/history/Brief.html during a press day in February 1940. (Alfred Price, Spitfire MkI/II Aces 1939-41, 1996 p. 11.) The armoured windscreen, fuel tank cover and bulged canopy is obvious, as is the straight aerial mast and early markings without finflash and serial number, the latter a feature of K and L series Spitfire Is built pre-war. (Ted Hooton, Spitfire Camouflage 1938-1940, Scale Aircraft Modeling Vol 5 No. 7 November 1982.)