The use of 100 Octane Fuel in the RAF pt 2

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Fass
Thanks for the comment and I agree about the words used.
Looking at the scenario outlined you are correct but the problems of having mixed fuel on different squadrons in wartime are numerous.

1. Squadrons are based at stations in peacetime but no in war. In the BOB squadrons were rotated between no 11 Group and No 13 Group for time to recover and retrain. So you would have to take the fuel with you. The option of leaving the aircraft behind doesn't really work as they need to have work done on them. You don't want a fleet of worn out aircraft in the front line.
The logistics of moving the fuel around would be huge

2. Squadrons are merged for instance into the big wings. One of the problems of the big wing was that they merged types such as Hurricanes and Spitfires which made them difficult to handle as they had a different performance. Throw different fuel into the mix and you have four differing performances, Hurricanes with and without 100 Octane plus Spitfires with and without 100 Octane

3. What are new aircraft built to, with or without the 100 Octane

There are other problems but with all the many of hundreds of books about the BOB you would think that something would have been mentioned if these problems existed.
 
Maybe I missed it Glider but do you have a list of the order in which the stations received the 100 fuel? I would imagine it would start with the stations in south-east England (11 Group) and gradually radiate out to stations in northern Scotland, Wales and Northern Ireland.

fass, you wouldn't have aircraft stranded at bases for they could be fueled with whatever fuel was available to get them back to their home base. The 100 fuel was because the Merlin got an increase in allowable boost pressure. The Merlin would run on the lower grade of fuel just fine as long as the boost was kept below the boost pressure of the lower rated engine.
 

I am afraid that I don't have a full list as to which field was issued with the fuel at what date. We do have a list of the first 21 stations that were to be issued with the fuel. These were

ACKLINGTON 13 Group
BIGGIN HILL 11 Group
CATTERICK 13 Group
DEBDEN 11 Group
DIGBY 12 Group
DREM 13 Group
DUXFORD 12 Group
HORNCHURCH 11 Group
LECONFIELD 12 Group
MANSTON 11 Group
MARTLESHAM HEATH 11 Group
NORTHHOLT 11 Group
NORTH WEALD 11 Group
TANGMERE 11 Group
TURNHOUSE 13 Group
CROYDON 11 Group
ST. ATHAN
WITTERING 12 Group
CHRUCH FENTON 12 Group
GRANGEMOUTH 13 Group
FILTON 10 Group

These are of course stations not squadrons. All these would have had more than one squadron and you can imagine the confusion if one squadron on a station was supposed to have a different fuel from a different squadron.
 
As I understand it the modifications to enable an aircraft to use 100 octane fuel was a simple recalibration or ajustment of the boost limit device and the addition of a control device in the cockpit to over ride the normal limit and allow the extra boost.

take standard engine made to run on 87 octane fuel at 6lb of boost. The supercharger will supply this amount of boost all the way to 16,250ft. Engines were first reset to allow 9lbs of boost which the supercharger would NOT supply all the way up to 16,250ft but only to a lower altitude. Engines were later reset/manufactured to allow 12lb of boost but again the supercharger could only supply this bost to a still power altitude above which the performance dropped back to the lower settings. above 16,250-17,000ft there was no difference in performance between an engine running on 87 octane and one running on 100 octane.

If plane was forced to land at a field that had no 100 octane fuel the answer was simple, put in enough 87 octane to get back to the home feild and fly normally, just don't hit the boost over ride button on the way home.

100 octane might cause lead fouling of the spark plugs in certain types of engines which is why all engines types that might use it had to be tested first before operational permission could be granted.
 
Glider, do you have a time frame for those first 21 stations?

I am afraid that I don't. We do know the following
1) that the transfer was being planned as early as the 7th December 1939 when the letter was written by FC admin to HQ.
2) That the issue of the fuel to the squadrons should be made as soon as the depots for the stations had been filled with the 100 Octane Fuel
3) Some squadrons started using the Fuel pretty quickly
North Weald started using it on the 16th February 1940 as mentioned in 151 squadron Opps ready book. Hurricane Squadrons in France were also using the fuel in May, No 1 Sqd starting on the 18th May at Berry-Au-Bac.
Digby Squadrons started operating with the fuel on 21st March
Hornchurch on 16th March
Drem on 16th February

Clearly this was a fluid situation as the French Stations didn't show on the initial list of stations to be so equipped. I wish that I did have this information but do not.

Hope this helps
 
In "I kept no diary" by Air Commodore F.R Banks. He mentions that he gave a paper in Jan of 37 in which he pleaded for the development of British military enginess to take 100 octane fuel. Which despite citical opinion from oil company representaives the Director of Technical Development of the British Air Ministry agrred with his paper.

"So by 1940 the Merlin's power was increased by this fuel from a combat rating of 1,000(plus) bhp to over 1,300 bhp, and 100 octane became available to Fighter Command ready for the BOB..."

"In June 1930, only 3 months before the start of WWII, a company tanker, the Beaconhill, set sail across the Alantic for the UK. with a full cargo of 100 octane fuel. We began stockpiling the this fuel though the decision to use 100 octane for Fighter Command was not made until March 1940 and that for its use by Bomber Command came in 1941."

The author also suggests for more detailed information:-

Milestones in Aviation Fuels by W.G.Dukek, D.P Winans and A.R.Ogston. Paper given at A.I.A.A. Designers and Operators meeting, July 1969, Los Angeles.

Sorry I couldn't scan the extract as I am still unpacking after my relocation to NZ.
 
Below please find documentation related to 100 octane use by the RAF leading up to and during the Battle of Britain:



Emergency +12 lbs./sq. in. Boost Operation: Pilot's Notes, Merlin II, III and IV, 4th Edition, April 1940, page 6.


Handling of Merlin in Hurricane, Spitfire and Defiant Aircraft, H.C.T. Dowding, C-in-C Fighter Command, 1 August 1940:


611 Squadron Operations Record Book


74 Squadron Operations Record Book


602 Squadron Operations Record Book


151 Squadron Operations Record Book


David Ross, The Greatest Squadron of Them All, The Definitive History of 603 Squadron, RAauxAF, (Grub Street, London, 2003), p. 125.


Alec Harvey-Bailey, The Merlin in Perspective, (Rolls-Royce Heritage Trust, Derby, 1983), p. 85.


Alfred Price, The Spitfire Story, (Arms and Armour Press Ltd., London, 1986), p. 74.


Flight, No. 1631 Vol. XXXVII, The Outlook, March 28, 1940.


Flight, January 6th 1944, p. 22.


W.G. Dudek and D. R. Winans, excerpt from AIAA Paper No. 69-779, Milestones in Aviation Fuels, (Esso Research and Engineering Company, New York 1969.) p. 319.



A. R. Ogston, excerpt from History of Aircraft Lubricants (Society of Automotive Engineers, Inc. Warrendale, PA USA), p. 12.


V. A. Kalichevsky, The Amazing Petroleum Industry, (Rheinhold Publishing Corporation, New York, 1943), p. 7.


RAF Website
The Royal Air Force - History Section

"All benefited from the replacement of 87 octane petrol with 100 octane, which allowed the engines to run at higher boost, and increased the Spitfire's speed by 25 mph (40 km/h) at sea level and by 34 mph (55 km/h) at 10,000 feet."

Al Deere, Combat Report - 26 May 1940 , 54 Squadron


F/Lt Brian Lane, Combat Report - 26 May 1940, 19 Squadron


P/O John Bushell. Combat Report, 18 May 1940, 151 Squadron


F/LT. John Webster, Combat Report - 28 July 1940, 41 Squadron


F/Lt George Gribble, Combat Report - 15 August 1940, 54 Squadron


P/O R.D. Elliott, Combat Report - 9 September 1940, 72 Squadron


56 Squadron Combat Report, 9 May 1940


F/Lt I. R. Gleed, 87 Squadron, 18 May 1940


602 Squadron Spitfire I in pre Battle of Britain camoflage and marked for 100 octane fuel


609 Squadron Spitfire I in pre Battle of Britain camoflage and marked for 100 octane fuel


610 Squadron Spitfire Mk I at Hawkinge in early July 1940. Note the petrol bowser marked for 100 octane fuel.


Spitfire Mk II P7420 with 19 Squadron, September 1940, Note the petrol bowser marked for 100 octane fuel.



For further reading and additional documentation please see:
Hurricane Mk I Performance
Spitfire I vrs Me 109
 
Excellent work, Mike! The Operations Record Books are the best sources, primary sources. Magazine articles and books have to be taken with a grain of salt. We have to be careful with magazine articles, especially during the war. Deception and Propaganda are not only german inventions. And after the war many writers just took for granted what was written then. And journalists in general...

But if these Operations Record Books still exist, there is an easy way to prove it: Someone has to check the books of ALL squadrons involved for a note like "100 octane fuel now in all aircraft". Did I say easy? Of course it's not. But as long as nobody does that, there will be discord on this topic.

And Juha, I'm totally d'accord with you. I said it is likely but if this thread is to be a discussion, we have to let the people discuss. I was definitely expecting Kurfürst bringing his own proof. That's all.

And let's hope that this topic brings even more interesting scans.

Krabat
 

This statement is without doubt incorrect. In May 1940 the UK had a stockpile of 240,000 tons of 100 Octane and the figures are supported by original documents as supplied to the Oil Committee copies of which were posted on earlier threads. I am afriad that I am away from my home PC which has my copies.

The summary given at the start of this thread shows how stocks increased during the BOB, there was never a shortage. Had there been its safe t say that the experimental production of 33,000 tons would have continued and probably extended.


I hope this helps
 
I think Mike Williams posting covers this but its fair to say that Kaufursts argument was that only 18 fighter Squadrons and 2 Blenhim squadrons had the 100 Octane Fuel. This was was obviously incorrect.

I am not a moderator and had nothing to do with his banning, also I made no complaint about his comments to anyone despite what most people would consider to be agressive statements.
The Moderators on this forum may not be perfect but they are pretty dammed good and I wouldn't fancy their role. They don't tend to react in this manner on a whim and you can be sure there are good reasons for any action they take.
I will now finish blatently sucking up to them and go back to my holiday in the Wet (make that very wet) Midlands.

For those who may not have seen the earlier threads every statement, figure, observation and stastic has been supported by original documentation not books or articles.
If there are any doubts please PM me and in a weeks time I will be able to send you copies or links to them. I cannot be fiarer than that.

What everyone has been waiting for
 
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I think Mike Williams posting covers this but its fair to say that Kaufursts argument was that only 18 fighter Squadrons and 2 Blenhim squadrons had the 100 Octane Fuel. This was was obviously incorrect.

for true the Willams post don't prove that Kurfurst fail on the 18 squadrons, there are only ~15 squadrons in Williams post
 
Hello Vincenzo
I noticed that also but there are more in the links Mike provided, especially on the Hurricane Mk I page.

Juha
 

1. I took no sides in the argument. I was making a general statement about discussions.

2. This was not an early state of discussion. This was part 2 (a second thread opened) for the same discussion. The first one was closed because both parties were flaming and being rude to one another. This thread was opened and both parties were told not to let it get out of hand.


Sorry Joe, did not read your post before I responded with mine.
 
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Thanks FLYBOYJ, parsifal and krabat!

Hi Juha:

I agree that there are sufficient primary sources and credible literature citations available in the various threads on this board and elsewhere such that there is really little mystery left regarding the conversion of Fighter Command to 100 octane fuel. I can't see the point of putting much more research time in to the subject as I wouldn't expect to increase my understanding of events to any significant degree.

Perhaps the following will further flesh out the story.

Air Ministry document AP1590B/J.2-W dated 20.3.40 clearing +12 boost states:
1. The emergency use of higher boost pressures up to +12 lb/sq.in. is now permitted for short periods by operation of the modified boost control cut-out.

The Spitfire I Pilot's Notes states:
"When using 100 octane fuel, +12 lb./sq.in. boost, obtained by operating the boost control cut-out, may be used for short periods."


Air Chief Marshall Dowding's memo dated 1 August 1940
states:
"The use of the automatic boost cut out control enables the pilot to get an emergency boost of + 12 lbs. per sq.in. from the engine for 5 minutes when circumstances demand it. Some pilots "pull the plug" with little excuse on every occasion."

Understanding that 100 octane fuel is required to safely operate the boost cutout, pull the plug/tit or obtain +12 lbs emergency boost on Merlin II and III engines equipping Spitfire Mk I and Hurricane Mk I, we can see that following pilots comments demonstrate use of 100 octane fuel. These are obviously highly condensed; please see the links or citations for the full accounts.

Pilot accounts from Hurricane Squadrons:

56 Squadron Combat Report noting +12 boost for Hurricanes, 9 May 1940:
S/L J.O.W. Oliver, 85 Squadron, 10 May 1940: "... I pulled the plug."
F/O Paul Richey, 1 Squadron, 11 May 1940: "...boost-override pulled."
F/O E. J. Kain, 73 Squadron, 14 May 1940: "...pulling his boost cut out..."
P/O D. W. A. Stones, 79 Squadron, 14 May 1940: " I now pulled out the emergency boost-plug for the first time ever..."
P/O R. P. Beamont, 87 Squadron, 15 May 1940: "I pulled the tit'* for over-boost... *Emergency boost over-ride on the Merlin engine."
S/L E. M. Donaldon, 151 Sqdn., Combat Report, 18 May 1940: "I pulled the plug and climbed at 10 lbs boost…"
P/O John Bushell, 151 Sqdn., Combat Report, 18 May 1940: "I used full 12 lb boost (pulled the plug) and overtook EA rapidly."
P/O F. B. Sutton, 56 Squadron, 18 May 1940: Vitry, France: "...I had to pull the tit... Emergency boost control giving extra power"
F/O C. F. G. Adye, 17 Squadron, 18 May 1940: "...pulled emergency boost control..."
F/Lt I. R. Gleed, 87 Squadron, 18 May 1940: "At about 100 feet I straighten up, pull the tit *; a jerk as my supercharger goes up to twelve boosts."
F/Lt I. R. Gleed, 87 Squadron, 19 May 1940: "Here goes with the tit. A jerk - the boost's shot up to twelve pounds; speed's increased by 30 m.p.h."
F/O C. F. G. Adye, 17 Squadron, 19 May 1940: "...pulled emergency boost..."
Sgt. L.H.B. Pearce, 79 Squadron, 20 May 1940: "Pulled tit..."
Sgt. J. C. Harrison, 229 Squadron, 28 May 1940: "I pulled the emergency boost and followed him down still firing."
P/O C. M. Simpson, 229 Squadron, 29 May 1940: "...I followed it down with boost out and pulled."
Sgt. P. Ottewill, 43 Squadron, 1 June 1940: "...automatic boost cut-out pulled."
F/Lt. R. G. Dutton, 145 Squadron, 1 July 1940:...pulled the plug..."
P/O G. E. Goodman, 1 Squadron, 18 August 1940: "...I pulled the plug..."
P/O Wicks, 56 Squadron, 30 August 1940: "With full throttle emergency boost..."
P/O J. R. B. Meaker, 249 Squadron, 6 September 1940: "...so I pull the plug..."
F/Lt J. A. Kent, 303 Squadron, 9 September 1940: "...I pulled the boost override plug..."
P/O T. F. Neil, 249 Squadron, 18 September 1940: "Plug pulled..."
P/O R. G. A. Barclay, 249 Squadron, 27 September 1940: "I had to use automatic boost cutout to catch up the 109."
S/L A. A. McKellar, 605 Squadron, 7 October 1940: "I followed one, pulled my boost control, and speedily made up on him."

Pilot comments from Spitfire Squadrons:

F/O D. H. Watkins, 611 Sqdn, 2 June 1940: "…emergency boost"
P/O John Freeborn , 74 Sqdn, 24 May 40: "boost cut out"
P/O Colin Gray, 54 Sqdn, 25 May 40: "…emergency boost tit"
P/O Al Deere, 54 Sqdn, 26 May 40: "12 boost"
F/Lt Lane, 19 Sqdn, 26 May 40: "12 lb. boost"
P/O M. P. Brown, 611 Sqdn, 2 June 40: "boost cut out"
F/Lt John Webster, 41 Sqdn, 19 June 40: "12 lbs boost"
F/Lt D. P. Kelly, 74 Sqdn, 28 July 40: "boost cutout"
F/Lt John Webster, 41 Sqdn, 28 July 40: 12 boost"
F/Lt John Webster, 41 Sqdn, 29 July 40: "twelve boost"
P/O George Bennions, 41 Sqdn, 28 July 40: emergency boost"
P/O Art Donahue, 64 Sqdn, 5 August 1940: "…emergency throttle"
F/Lt John Webster, 41 Sqdn, 8 August 40: "12 boost"
F/O R. W. Wallens, 41 Sqdn, 11 August 40: "12 lbs boost"
F/Lt George Gribble, 54 Sqdn, 15 August 40: "12 boost"
F/O Hugh Dundas, 616 Sqdn, 15 August 40: "through the gate"
F/Lt Robert F. Boyd, 602 Sqdn, 18 August 40: "10 lbs boost"
P/O James Morton, 603 Sqdn, 28 August 40: "pressed the tit"
P/O Ronald Berry, 603 Sqdn, 31 August 40: "emergency boost"
Sgt Jack Stokoe, 603 Sqdn, 1 September 40: "boost override"
P/O Roger Hall, 152 Sqdn, 4 September 40: "energy boost"
F/O Robert Oxspring, 66 Sqdn, 6 September 40: "through the gate for emergency power"
P/O R. D. Elliot, 72 Sqdn, 9 September 40: "MAX Boost (12 lbs)"
F/O Brian Macnamara, 603 Sqdn, 27 September 40: "full throttle and with the red lever pressed"
P/O Bob Doe, 234 Sqdn: "pull the plug"
Geoffrey Wellum, 92 Sqdn" "emergency boost override"
P/O David Crook, 609 Sqdn, 30 September 40: "'pulled the plug', i.e. pushed the small handle on the throttle quadrant that cuts out the automatic boost control thus allowing one to use emergency power."
F/O D. McMullen, 222 Sqdn, 15 October 40: "12 boost"

The squadrons noted above are as follows: Spitfire – 19, 41, 54, 64, 66, 72, 74, 92, 152, 222, 234, 602, 603, 609, 611 616. 610 squadron Spitfires are shown being refueled with 100 octane above. Hurricane – 1, 17, 43, 56, 73, 79, 85, 87, 145, 151, 229, 249, 303 605. I'm quite sure more accounts and documentation will be found demonstrating 100 octane use by other squadrons during the Battle of France, during the Dunkirk evacuation and during the Battle of Britain.
 
I'm no math wizard, but that looks like 31 different squadrons to me.

I've yet to read a combat report or anecdote from an RAF pilot stating that they 'only had 87 Octane fuel' for a particular mission or while with a particular squadron.
 
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