It is nice to see that Kurfy does not believe that it was only 16 squadrons in Sept anymore.:)

its progress of sorts;)

http://www.spitfireperformance.com/spit1vrs109e.html

Just for fun let's just see what passes for "opinion" on the Kurfurst 109 Forum
http://kurfurst.freeforums.org/a-pos...ters-t302.html

And there's nooo problem quoting from lane's websites when it apparently puts the Spitfire in a bad light http://kurfurst.freeforums.org/mk-xi...ints-t114.html In general Good for laughs but go elsewhere for objectivity.

:lol:
Great summary, thanks!

We will see if Kurfy can come up with such proofs when it comes time to model the 1.98ata Bf109K-4.

Not very likely.;)

[QUOTE=NZtyphoon;423177]http://www.spitfireperformance.com/spit1vrs109e.html

Oh, its refreshing that 'lane' has revoked his earlier err, 'opinion'. At least he is no longer in denial of the 1-minute rating like he was propagating for years.

More interesting things in the article, since it has sparkled such interest, and to establish the 'credibility' of that site's articles and lane's opinion expressed them:

1, In his comparisons of engine outputs, he displays one the 1100 PS DB 601A-1 with the old type supercharger, even though the power ratings for the ones with the new supercharger are present in the very October 1940 DB 601 manual he lists as a source.

2,Similarly, he completely ignores the E-x/N models in all his comparisons, which he claims appeared 'towards' the end of the Battle, and in penny pocket numbers', when in fact they were present in July 1940 already. In contrast the Spitfire II which appeared a good month later than these and equipped only a handful Squadrons by the time the great daylight fighter engagements all but ended, received a large amount of his attention, insisted as an improved type, when in fact his own site's flight trials leave no doubt about it's indifferent performance in comparison of the badly mauled Spitfire I. Both were were inferior to the 109E with 601N engines, which is likely the cause about the silence and lies about the latter type's absence from the engine and flight performance comparisons. They would make Spitfires look bad I guess.

3, In connection, he 'forgot' to mention and list the outputs of the 1175 PS DB 601Aa, which he claims to have been never been used on any but export Emils. He even 'quotes' Olivier Lefebvre, who has clearly stated that about 1/3 of the DB 601 production was the Aa model, and that all E-7 and E-x/B models were found with the Aa. So, in short ignores one of main engine types and simply selects the lowest performance Emil in his comparisons, misquotes Olivier Lefebvre and just plain dishonest.

4, Again in connection, he 'forgot' to mention the fact that the DB 601 had an option to overrev the engine above FTH and increase engine power, a practice used and described by Steinhilper in his book, who he as usual selectively qoutes enthusiastically to prove that the Emils propeller was 'troublesome'.

5, He misquotes the WNr. 1774 trials, describing them as running over the official boost limits. In fact the said trials note the engine was measured in bench test and was found to develop about 50 HP less than the nominal figures, and the test results were corrected for the nominal powers. Needless to say, 'lane' only shows the figures which depict the WNr. 1774 down on power.

6, He 'forgot' to mention the automatic propeller system on the Bf 109 having been introduced in late 1939 (listed in the December 1939 109E short manual he used to 'prove' the 1-min rating was not cleared yet...) and tries to create the impression it was an automn 1940 thing just introduced.

7, He 'quotes' the following meeting for the 100 octane issue - at this stage of uniform disbelief, surely to be called partisan attitude:

The Co-ordination of Oil Policy Committee noted in the conclusions of their 18 May 1940 meeting with regard to the "Supply of 100 Octane fuel to Blenheim and Fighter Squadrons" that Spitfire and Hurricane units "had now been stocked with the necessary 100 octane fuel". 35

As can be seen the actual document speaks of no 'Spitfire and Hurricane' Squadrons' (lane's brainchild) but the 'units concerned'. Obviously the actual text got in the way of the agenda.

http://www.wwiiaircraftperformance.o...-100octane.jpg

8, Another curious way of 'quoting' (cropped) documents is this.

This is how Spitfire I limits appear in his article:

http://www.spitfireperformance.com/spit1pn-12lbs.jpg

... and this is the full version:

http://www.spitfireperformance.com/spit1pn2-a.jpg


As you can see the the normal limitations of the Merlin III in the Spitfire I got strangely 'absent' for the article's purposes.

Its no wonder that most of us who have been aware of this site's and it's owners manipulations give very little credit to his articles. We all understand how documents are being manipulated, selectively quoted and falsified on that site.


Members on my site are free to express whatever opinion. Moderation is very very conservative, and we only dump mindless troublemakers - actually only one was flushed down in the toilet in the years, who's participating in this thread and who was permbanned from ubi about seven times and from ww2aircraft.net three times :D . I personally believe that Purple Fang is a bit overzelous in that, but probably he just have enough of the lies spread intentionally my some who I will not mention here (we all know who he is and his history). He is free to express his opinion as long as he respects other members.

And as for finding it 'good laughs', personally I have learned a thing or two from members who have been involved in 109 restoration a good deal. Maybe our estimeed but failed NZ student who fancies himself as a 'historian' :D :D :D with a lots of spare time find it good laughs, but they apparently do not share your judgement, for all what its 'worth'. In that case I'd suggest not to visit and quote my forums, as it makes you look funny that at the same time you are so aware of its postings, and people may misjudge you as someone not to be taken too seriously, quoting from forums you claim to a good laugh, and responding to people you claimed to have put on ignore. :D

Just don't get banned again when it happens again, Milo Morai, luftluuver, billythekid,, KrazyKanuk, Al Schlageter or whatever else name you were using until you were permabanned for calling Oleg Maddox an imbecile when he choose to model it. ;)

Until that, you can still read of 1.98ata 109Ks here: http://www.kurfurst.org/Engine/Boost...arance198.html

Crumpp/Kurfurst:

All you have to do is show us proof that RAF FC during the BofB flew at least one, operational squadron, Hurricane/Spitfire 87 octane combat sortie. Just one...

You have presented your thesis and now we want proof.

I'm still waiting for your proof.

Ah poor Barbi, telling lies again. Got proof?

Glad you posted that link Barbi. Here is an excerpt:

All will notice that there is no official documentation, just someones text. This in contrast to the reams of documentation you want provided on 100 octane fuel during the BoB.

Also notice that it is for an boost increase, not that it was done. Yet, how many reams of documentation have to be provided for 12lb boost.

Next, you do PURE SPECULATION on the numbers so modified as C3 fuel was also used in other DB605 engines besides the DB605D.

Then there is the question when the time comes if Crumpp will back up your PURE SPECULATION.

Can someone please post No. 2 or Summary of Conclusions of SIXTH Meeting?

Edit: Found them ...

http://forum.1cpublishing.eu/attachm...1&d=1308308865
http://forum.1cpublishing.eu/attachm...2&d=1308308889

Says the professional Kurfurst Or Barbi or Adam whatever who knows all about being banned ; (for some reason someone who claims to have very little interest in the RAF is still obsessed with 100 Octane fuel and presents the same "evidence" to "prove" his "case"...)
or blocked 10 times from Wikipedia and whining about it, because its all a plot to discredit poor Kurfurst before, finally, being blocked indefinitely but its all a plot and whining about it; and as a sockpuppet blocked (this is the same Kurfurst who falsely accused another editor of being a sockpuppet)

NZt, I don't think Barbi would want it known why he got banned from Aces High.

Do we have an entertainment subforum here somewhere where this thread could go to?

:-P

Oh, Minortroll goes on to his daily routine, the petty waste of his days. 'twas, for some time, of some entertainment value, but as with most shows and people with little substance in them, the novelty wore off pretty quickly and it's now just the boring routine - another nolifer kid who has got his buttocks handed to him a few times, and having no purpose for himself, now found that in a lifetime revenge campaign. On the internet. :D

I wondering though, how uneventful your life may possibly be, spending it like this. I guess you should marry luftie, he spent the last ten or twelfe year of life doing the same until nobody really gave a flying ack-ack about him. I sense you are just from the same material. Well, I guess it's time to wish you a lot of good fun. ;)

I guess its born out of nostalgic feelings for Ubizoo. I miss Ivan though. :D

Ivan doesn't miss you though ;) as do the Mods on all the boards you post on.

:grin::grin::grin::grin: Talking about yourself again; sad, sad, sad vindictive Barbi. :cry::cry:

Is it possible that someone can post the available papers from the Co-ordination of Oil Policy Committee meetings?

I have asked David (Glider) a couple of times to post the papers, but he is appearantly not so willing to publicly anything else than the crops he has posted so far.

I can post you those if you want.

Would indeed be nice to have all papers collected in one post.

I've only seen parts of 5th and 6th meeting, but it's not clear what "units concerned" means in the context. Does it mean the stations that should store only 100 octane (i.e. the Blenheim squadrons), or does it mean the stations that should receive 100 octane and keep one tank 87 octane? Are these all fighter stations with Hurricane and Spitfire or only some selected stations? The 5th meeting only specifies those stations with 100 octane only, but doesn't contain a list of the others. Maybe this list is in one of the earlier meetings.

Also we always see only the "summary" and I would expect that other pages describe the situation in more detail.

I have the feeling that the answer is within this papers.

Here's what I have, from Glider.

Part II.

With regard to "units concerned" as per above. Having looked at the WWII classified secret file with the title "AVIATION FUEL (100 OCTANE) SUPPLIES", it can be seen that when read in context, the file is refering to the enclosure containing a letter dated 7th December 1939, ref: FC/S.15447/76/EQ.2, under cover of Air Vice-Marshal, Air Officer i/c Administration, Fighter Command, Royal Air Force.

This letter details the operational stations at which the 100 Octane fuel will be required "in the first instance". The letter also states that "all non-operational stations in the Fighter Command will also have to hold certain quantities of this fuel for visiting aircraft". The letter goes on to list the non-operational stations and stations which do not have Hurricane or Spitfire aircraft at the moment, that will need the fuel. The letter also mentions the need for "disposal instructions for varying quantities of D.T.D224 and other grades of petrol that will not be required in such large quantities on the introduction of 100 Octane fuel".

A letter later on in the file, dated 12th December 1939, can be seen to be responding to the AVM's letter, ref: F.C. 15447/76/E.Q.2, on behalf of the Air Officer Commanding-in-Chief, HQ Fighter Command. This letter says "I am directed to confirm that 100 Octane fuel is approved for use in Hurricane, Spitfire and Defiant aircraft, and state that issue will be made as soon as the fuel is available in bulk at the distribution depots serving the Fighter Satations concerned" (the ones listed in the AVM's letter dated 7th December 1939). This letter also says that "from an operational point of view it is essential that supplies in bulk at the distribution depots should be available before general use commences and that it is not possible to state a day on which 100 Octane fuel will come into use on all the approved stations" (the ones listed in the AVM's letter dated 7th December 1939). The letter goes on to say "the date on which the fuel may be brought into use depends upon the rapidity with which (a) supplies in bulk can be put down at distribution points, and (b) bulk storage could be made available at the relevant stations". The letter also says that "the Petroleum Board have been instructed that storage in bulk at certain distribution points is to be arranged with the least possible delay and tanks at these ponts are being "run down" to provide the necessary accomodatoin".

I think it is reasonable to consider that the term "with the least possible delay" means that 100 Octane fuel was was used in all Fighter Command approved aircraft, which has been given as Hurricane, Spitfire and Defiant, very soon after the letter dated 12 December 1939 from the office of Air Officer Commanding-in-Chief, HQ Fighter Command, RAF.

Talisman

For the record 'those crops' as Kurfurst so describes the paper are the only part of those meetings that dealt with the purchase, storage and distribution of 100 Octane fuel and Kurfurst is aware of this. It isn't a case of being unwilling, its a case of there is nothing more of relavence.

He expesses doubt but has had ample time to obtain copies himself to prove it one way or the other.

I am pleased that he has finally posted the papers available which show the trail in context rather that emphasising one paper.

Like I said, he is not very willing to show anything but crops.

He DOES insist every time to see the full papers I use to post though, and as I recall he seen them in full every time.

Indeed.

"At the last meeting A.M.S.O. referred to a proposal that certain Fighter and Blenheim Squadrons should begin the use of 100 octane fuel.."

Quite clear-cut isn't it.

Here's my take on this "units concerned" business, working from most recent to oldest:

By May 18th, these "units concerned" has been stocked with the necessary 100 octane

Prior to May 18th. There are two separate lines of discussion.
One relates to Bomber command and the stocking/ holding of two fuel types a Blenheim statinos, mainly stations Wyton, Watton, Waattsiham and West Raynham.

Fighter command, on the other hand was also subject to the same "proposal" that "certain units" should "begin to use 100 octane". There was some discussion about whether or not the existing spitfires and hurricanes could actually convert to the 100 fuel without substantial modifications. However, this concern was proved unfounded. They could use the 100 fuel.

So who are these "certain units"?
Well, as Talisman identifies in his post above, these "certain units" are the "squadrons armed with fighters and Blenheims" as specified by Assistant Chief of the Air Staff - who sits ABOVE both fighter and bomber command, which is why, form the overall RAF perspective this refers to "certain units", and not ALL units.

I think it's entirely fair to suggest, that from the perspective of fighter command, this referred to ALL fighter units.

I am in agreement with Talisman that by May 18th, all of these "units concerned" were using 100 Octane. And that their Spitfires and Hurricanes could use the fuel WITHOUT considerable modification, as per the statement of Mr Tweedie, at the May 1940 meeting.

There is a sting in the tail though, while the Spits/Hurris could use the 100, they would not get the performance benefit until the modifications had occurred to each individual aircraft.

And why do you think it does not refer to the original 16 squadrons?

Name these 16 original squadrons.

Which "original 16"?
Who identifies these "original 16". I've not seen this bit yet (it might be too far back in the thread).. I'd happily accept a fresh link, if you'd oblige.

Assuming it were only these 16 (none of which I can find), if say, one of these 16 (as yet unidentified) squadrons was based at at a station with other units not in the 16, would that station have had both fuels?

Do you agree that the "certain squadrons" are those squadrons which are referred to in the request by the ACAS?

Lets' start with establishments common ground, and work from there.

Good post pstyle. Just a thought...I'm not sure about your last statement regarding not getting the performance benefit until the modifications had occurred to each individual aircraft whilst using 100 octane. It may in fact be the case that using 100 octane without the modifications may actually have allowed for greater power than the 1310 hp provided by +12 lbs., though likely resulting in increased strain on the engine.

R.D.E.6 memo dated 14/11/39 states "The modifications to the boost control cut out to limit the maximum boost to 12 lbs. sq.in. are simple and in hand (otherwise full throttle would give about 17 lbs. sq.in.)"

See also comments of Sgt. R. C. Wilkinson, 3 Squadron, 14 May 1940

One possibility as to which squadrons comprised the 16; 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

One can see from the following listing that many units had converted prior to the Battle of Britain

111 Squadron ORB 15 February 1940
151 Squadron ORB, 16 February 1940
602 Squadron ORB, 16 February 1940
611 Squadron ORB, March 1940
74 Squadron, March 1940
100 Octane Fuel - Issue of., 12th December, 1939
A.P.1590B/J.2-W, Merlin II and III--Use of +12 lb./sq.in. Boost Pressure--Alterations, 20 March 1940
Emergency +12 lbs./sq. in. Boost Operation: Pilot's Notes, Merlin II, III and IV, 4th Edition, April 1940, page 6.
Air Chief Marshal H.C.T. Dowding, Handling of Merlin in Hurricane, Spitfire and Defiant Aircraft, 1st August, 1940

56 Squadron Combat Report, 9 May 1940: twelve boost
S/L J. O. W. Oliver, 85 Squadron, 10 May 1940: 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: pulled out the emergency boost-plug
Sgt. R. C. Wilkinson, 3 Squadron, 14 May 1940: 12 P.S.I.
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
P/O F. B. Sutton, 56 Squadron, 18 May 1940: I had to pull the tit... Emergency boost control giving extra power
F/Lt. I. R. Gleed, 87 Squadron, 18 May 1940: pull the tit *; a jerk as my supercharger goes up to twelve boosts
P/O John Bushell, 151 Squadron, 18 May 1940: I used full 12 lb boost (pulled the plug)
S/L E. M. Donaldon, 151 Sqdn., 18 May 1940: I pulled the plug and climbed at 10 lbs boost
F/O C. F. G. Adye, 17 Squadron, 18 May 1940: pulled emergency boost control
F/O C. F. G. Adye, 17 Squadron, 19 May 1940: pulled emergency boost
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
Sgt. L. H. B. Pearce, 79 Squadron, 20 May 1940: Pulled tit
P/O John Freeborn, 74 Squadron, 24 May 1940: boost cut-out
P/O Colin Gray (NZ), No. 54 Squadron, 25 May 1940: I pressed the emergency boost tit
P/O Colin Gray (NZ), No. 54 Squadron, 25 May 1940: +12 lbs.
P/O Al Deere, No. 54 Squadron, 26 May 1940: 12 boost
F/LT Brian Lane, 19 Squadron, 26 May 1940: automatic boost cut-out
F/LT Brian Lane, 19 Squadron, 26 May 1940: 12 lb. boost
Sgt. J. C. Harrison, 229 Squadron, 28 May 1940: I pulled the emergency boost
P/O K. B. McGlashan, 245 Squadron, 28 May 1940: We’d boost an extra four pounds, from eight to twelve
P/O C. M. Simpson, 229 Squadron, 29 May 1940: with boost out and pulled
P/O T. D. Welsh, 264 Squadron, 29 May 1940: pulled boost cut-out
F/Sgt. G. C. Unwin, 19 Squadron, 1 June 1940: 12 Boost
Sgt. P. Ottewill, 43 Squadron, 1 June 1940: automatic boost cut-out pulled
P/O M. P. Brown, 611 Squadron, 2 June 1940: opened the boost cut-out
F/O D. H. Watkins, 611 Squadron, 2 June 1940: emergency boost
F/Lt. John Webster, No. 41 Squadron, 19 June 1940: 12 lbs boost
F/Lt. R. G. Dutton, 145 Squadron, 1 July 1940: pulled the plug
609 Squadron

It should noted lane that the squadrons you list are doing so well before the Sept date so often stated by some.

Yes, the historical record shows that in March 1939 when the planners were looking at converting 16 fighter squadrons to 100 octane, there were in fact only 16 operational squadrons (+/- 1) equipped with Hurricanes or Spitfires. Clearly more than 16 squadrons had converted to 100 octane before the Battle of Britain.

Mystery of the 16 squadrons solved. :grin:

Now the 1C devs can feel free to give our Spits and Hurries their badly-needed and much-deserved +12 lbs of overboost and resulting emergency 5 minutes or so 30 mph increase in top speed. The sooner the better - a "hotfix #2" would be just the ticket!!!!

I am all for it, but only if there are felt penalties for abusing/overboosting the engines of all sides longer as rated!!!

Like loosing power slowly or better a increased chance of throwing a rod or something like that, this combined with corrected oil and water temperature changes.

agreed.

30MPH extra speed only ?!!!!!!!!!!!!!!

why not 300mph ?:mad:

+1

http://www.il2bugtracker.com/issues/174

Where have YOU been? :rolleyes:

Thanks Lane for the great job of putting things together in one post! :)


I am impressed by that battle report:
F/Lt. R. G. Dutton, 145 Squadron, 1 July 1940: pulled the plug
The leader went max out and it took him 5min to reach gun range (400yrds) and even then he had to stay in line behind the DO17 because even his (maxed out) speed was hardly sufficient to keep chase!
The DO-17 was reknowned to be fast but, that fast!

And then, he used up all his ammo to "slow down" the DO17 and then his No.2 made a pass and finaly his No.3 shot the DO17 down!

Interesting reading.

~S~

I am not so sure "pulling the plug" has anything to do with 100 Octane use at all.

The 1937 RAF Training Manual has instructions for boost cut out independant of 100 Octane fuel.

Additionally this certificate list the boost pressure well above the rated 6 1/2 lbs without boost cut out. The only approved fuel for this aircraft is 87 Octane.

http://img19.imageshack.us/img19/255...ertificate.jpg

Hardly unexpected that the 1937 manual didn't have 100 fuel

Right, so it appears you can throw out all those combat reports that do not specify +12lbs or 100 Octane.

Like this one:

http://www.wwiiaircraftperformance.o...on-1july40.pdf

Can you post the instructions please?

1.) In the May 1939 paper that "16 Squadrons" was provisional, based on whether or not 100 Octane fuel supplies would decrease or increase. Paragraph 8 clearly states that.

2.) Individual squadrons were not allocated fuel, the fuel was clearly allocated to the RAF stations.

Explain to everyone Crumpp how the RAF allocated the fuel to 16 frontline fighter squadrons while denying the rest the use of the fuel. How was it done, what were the logistical arrangements and provide some documentary evidence for your speculation..


Do you know what Boost Cut Out means Crumpp? It means the pilot used the boost cut out control to reduce power once he had "pulled the plug" to go to +12 lbs boost, so you have it all backwards for a start. It doesn't matter what type of fuel the engine used, if there was provision for extra boost there was a boost cut out to allow the pilot to reduce power.

What this certificate does show is the maximum performance the Merlin III was capable of with 87 Octane fuel +10.55 lbs boost, 1,212 hp. The certificate also clearly says emergency 5 minutes maximum meaning that the engine had to have boost cut out.

What is interesting in that document is the HP at 4.2lb > 822. Hardly the 1/3 that was mentioned sometime before.

Really guy?

The aircraft is only approved for 87 Octane fuel.

You clearly had no idea of what the boost cut out is for so I explained...

So? For ages you have been swearing black and blue that because the Pilot's Notes stipulated certain engine limitations and certain types of fuels those were the limits observed no matter what, in spite of it being explained to you several times, very carefully, that supplementary slips were issued to the pilots with the Pilot's Notes revising such information when it was relevant.

Now, on the basis of this one test certificate you are saying what? That the engine limitations were not observed? I haven't noticed any pilot's notes stipulating 10.55 lbs boost maximum using 87 octane fuel, so I guess you want to withdraw all of your previous comments regarding the legal limits etc set by the pilot's notes?

You now want to claim that when pilots refer to pulling the plug it meant they went to 10.55 lbs boost on 87 octane fuel, right? Then present some documentary evidence showing that pilots were authorised to use 10.55 lbs boost on 87 Octane.

Then explain why Dowding found it necessary on 1 August 1940 to send a memo to All Groups, ALL Fighter Stations and ALL fighter squadrons stating that +12 lbs boost was only to be used in emergencies? Why not state +10.55 lbs boost, and send a separate memo to the supposedly small number of squadrons authorised to use 100 octane fuel?

http://www.spitfireperformance.com/dowding.pdf

Note he also uses the expression "Pulling the Plug" referring specifically to +12 lbs boost.

I will explain this ONE time and then I will probably ignore you as I don't think you have much to add. It is according to the training manual and fits with everything I have already told you about Operating Notes.

The 1937 RAF Training Manual explains the use of boost cut out. In 1937, 100 Octane was not an issue.

The certificate limitations appear to back up the use of the system.

That is completely independent of 100 Octane.

It means most of the reports you claim prove the use of 100 Octane fuel really have nothing to do with it at all.

Very interesting read, NZ.

I also like point 5 which states "The consequences of exceeding the engine limitations are liable to manifest themselves on some subsequent occasion, perhaps during night flying or over the sea ......"

Regardless of the type of fuel being used (the limits being different in each case) the damage being done is generally not instantainous and will not result in immediate loss of the engine (as I have heard it being argued in some threads), but will be dependant on how far over the limitations and for how long they're exceeded for.

To fully realise the damage being caused to the engines we would need to have resource management implemented in the game where this type of damage is accumilated and passed on to subsequent mission. (with maintenance being able to repair the damage ideally!)

It'd also make for interesting senarios where all the good planes are used up and we are only left with the bunkies! (Janes USNF had a good system like this for campains!)

Cheers!

Well one day, all those units will be equipped with 100 Octane. It is not proof that all of the operational units were using it. Why put the word out on something like the information in that memo piecemeal?

What is proof that that 100% of the operational units were NOT using is the Notes on a Merlin Engine found in the Operating Notes.

That is a fact.

Sometimes it will and sometimes it will not.....

It all depends and it is just as likely to end your trip that flight as the next if the motor is damaged.

I am not claiming anything outside of known facts, NzTyphoon. I will leave the speculation to you.

The known facts are that system was in place before 100 Octane fuel was around as evidenced in the 1937 RAF training manual.

The Operating Notes will specify the authorized fuel for the aircraft. The type Operating Notes clearly state that "ALL Operational Units - 100 Octane" after the fuel is adopted for all operational units.

We don't see that in any of the Operating Notes during the BoB. Only the Spitfire Mk II carried the 100 Octane specification. The rest require replacing the heads and in some cases, rings as well as the required modifications to the fuel metering system. This work was performed at Service Inspection intervals. Do you know what that means?

Absolute nonsense! The memo says nothing about "In Future, once 100 Octane fuel becomes available..." it was written in the present tense stating unambiguously that too many pilots were using +12 lbs boost for situations other than emergency.

Pure speculation on your part.

Nonsense - it has been explained to you several times that the operating limits posted in the Pilot's Notes were relevant to the fuel the engines were designed for, as explained long ago to you in the Pilot's Notes General 1st ed. Any alterations to those operating limits were issued to the pilots as supplementary slips which were then pasted into the Pilot's Notes. You continue to ignore this because it does not suit your "argument".

Not how it works by convention and Air Ministry law. The operating notes define the current airworthiness limits.

Wrong again: read the Pilot's Notes General (attached)

The March 20 1940 memo clearly states that new built aircraft already had the internal engine mods:

http://www.wwiiaircraftperformance.org/ap1590b.jpg

Given the production numbers for Hurricanes/Spitfires and RAF operational and combat losses prior to the start of the BofB, it is extremely doubtful that any unmodded aircraft were still in front line service. Production during March, April, May and June, and July, of 1940 would have amounted to approximately 1500 Hurricane/Spitfire aircraft, or greater then RAF FC's front line strength at the start of the BofB.

The memo clearly establishes that all RAF FC Hurricanes/Spitfires were modded for Hundred octane fuel and 12lb boost prior to the start of the BofB.

I hope you guys are aware that the line "Emergency 5 mins.max." is related to "95°C" oil inlet temperature?

http://forum.1cpublishing.eu/attachm...1&d=1337142966

This test certificate has a better layout: http://www.spitfireperformance.com/k...ertificate.jpg

The power curve is a simplified form of this graph: http://forum.1cpublishing.eu/attachm...1&d=1337143252
and most certainly only contains calculated values which were derived from certain reference values or were applied shorty under controlled conditions to determine the engine power.

So please tell us what there is written ... or at least tell us which chapter and paragraph.

This is from the Air Publication 129 Royal Air Force Flying Training Manual Part I - Landplanes; Revised June, 1940 (Reprint April 1941 incorporating A.L. No. 1), A.L. No. 2 from May 1941 is slipped in.

I doubt it would be just as likely. If you read the memorandum point one and two,

"A recent increase in the number of engine failures, due to the failure of bearings, is an inication that some pilots are over-stepping the engine limitations laid down in the Pilot's handbook.

2. The use of the automatic boot cut out control enables the pilot to get an emergency boost of +12lbs per sq in. from the engine for 5 minutes when circumstances demand it. Some Pilots "pull the plug" with little excuse on every occasion."

The wording of this memo suggest that the practice of exceeding the limits was quite widespread. Now if it was as you suggest a 50-50 chance of engine failure when the limits were exceeded then the culprits responsible for abusing their engines would be quickly identified and I expect grounded. The practice of exceeding the limits would only become common place if the pilots thought they could get away with it. Maybe thats why they put the wire seal on the boost control to make it obvious to the maintenance staff that it had been used. Then the pilot would have had to justify their use of boost after the mission.

As long as they didn't overheat their engines and the correct fuel was used the boost control still limits the boost available to stop destructive pre-ignition and detonation as a cause of engine damage. (ie if you run the 12lb boost on 87 octane fuel you could get servere and possibly imediate damage from detonation, but not with 100 octane fuel.) So what was left was damage caused by accellerated wear on the engine that was "liable to manifest themselves on some subsequent occasion"


http://www.spitfireperformance.com/dowding.pdf

For all you know 145 sqd is one of your 16 squadrons you claim were using the 100 octane. After all, action in that area is right in the front line and by your standards most likely to have the fuel.

Unles of course you can prove that they were not using the fuel which reminds me, to do that you need to prove which 16 squadrons or stations were using the fuel.

Any update?

I admit to not holding my breath

Also note section 6 So using +12 lbs boost did not inevitably damage the engine, but it was better for all concerned that the pilot let the ground crew know that he had gone through the gate - should the pilot neglect to mention that +12 lbs boost was used as Skoshi has mentioned, they could check to see if the throttle wire had been broken.

All frontline RAF aircraft were given a daily inspection whenever possible and this would be when any such issues were found and, if need be, notified in the aircraft's engine log.

BTW Some might remember this thread? http://forum.1cpublishing.eu/showthread.php?t=20117 £74.50 for a copy of the Mk I Pilot's Notes from Kew? v $15.9 from http://www.flight-manuals.com/ap1565a-vol1.html Apart from these there don't seem to be many original Spitfire I Pilot's Notes available.

Also note the Defiant used 100 octane and +12 lbs boost - the attachment is dated 24 5 (or 6?) 40 lower LH side

Wrong: this is simply your arbitrary "ruling" made on the basis of one document. Fact is Dowding used the phrase "pull the plug" in his 1 August memo, recognising that this phrase (and others such as "squeezed the tit") was pilot jargon for "used emergency boost" or +12 lbs boost - you have already tried to rule out all such pilot's reports based on some other such arbitrary concept, so if you don't like them being used, too bad.

Unless, that is, you can find a memo or other such document stating, for example, that, until further notice, 87 Octane fuel will be used by the majority of the RAF's frontline fighters.

Either that or find a list of units authorised to use 100 octane fuel, and/or an explanation of the logistical processes used by the RAF to ensure a limited supply of 100 octane directed at selected units or stations.

At the time 145 was based at Tangmere. Also based there were 43, 601 and the FIU. The FIU flew Blenheims so 100 fuel must have been available. It should also be noted that Tangmere was one of those stations listed in the Dec 7 1939 document http://www.wwiiaircraftperformance.o...0oct-issue.jpg

It shouldn't be that hard to identify those 16 squadrons should it Glider?;) So why the evasiveness in identifying these 16 squadrons by a certain party?

Good post 41Sqn_Banks,

I concur that "Emergency 5 mins.max." on the Inspection and Test Certificates is related to "95°C" oil inlet temperature.

Unfortunately I haven't seen a power curve for the Merlin III similar to the one you posted for another type. My understanding is that the power curve figures shown on the Inspection and Test Certificates were obtained through bench testing. In the case of N.3171 the engine Inspection and Test Certificate is dated 9-6-39 whilst N.3171's first flight occured on 10-11-39. The A.&.A.E.E. report on N.3171 notes:

"The engine installed in the aeroplane develops slightly less power under test bed conditions than that in K.9793, the aeroplane fitted with the 2-pitch airscrew. This could have the effect of reducing the top level speed by about 2 m.p.h. "

One can see that the power figures were not pulled from a chart given the differing powers obtained:

K.9703 Inspection and Test Certificate
N.3171 Inspection and Test Certificate

Ok, your opinion is noted. What do you want me to do? Agree with you when I know it is not the case?

Overstress an engine and it might fail then and might fail later. The point being, it will fail and its life is significantly shortenend.

That memo is telling the pilots of the RAF that reality. Overstress the motor and it will fail. There is a good reason why it was a requirement to log the use and have the motor inspected to ensure some reasonable life was left in it.

I know that banks.

The 1937 RAF training manual amends the RAF old definitions for engine ratings.

The only difference is the 1937 RAF Training Manual list's the system for take off purposes.

There you go, they are testing the engines on a bench at boost over-ride on 87 Octane.

Everything in aviation related to the airworthiness is tightly controlled and must be specified. The Air Ministry documents the standards and conditions they expect their pilots to use down to the point of defining the standards they expect if a pilot violates the airworthiness standards in an life threatening emergency.

The RAF instructs its pilots to balance and evaluate risk before taking the risk of moving outside of the airworthiness instructions. From 1937 on, they are able to use boost override.

Without the specific mention of using +12, an anecdote that makes any reference to boost override, pulling the tit, boost cut out, or anything other term related to the system is irrelevant to the use of 100 Octane.

This is what Dowding said about pulling the plug, boost cut out and +12 lb boost:

http://www.wwiiaircraftperformance.o...1aug40-pg1.jpg

This is what the pilots were doing when Dowding wrote the memo.

P/O Bob Doe, 234 Squadron
http://www.spitfireperformance.com/234-doe.jpg

Geoffrey Wellum, 92 Squadron
http://www.spitfireperformance.com/92-wellum-pg147.jpg

P/O David Crook, 609 Squadron, 30 September 1940
http://www.spitfireperformance.com/609-crook-p80.jpg

P/O K. W. MacKenzie, 501 Squadron, 5 October 1940
http://www.wwiiaircraftperformance.o...enzie-pg50.jpg


In many cases pilots would note use of 12 lbs boost or emergency power in conjuction with pulling the plug/tit, thereby establishing a direct connection between the various expressions related to emergency power.

P/O John Bushell, 151 Squadron, 18 May 1940
http://www.wwiiaircraftperformance.o...dn-18may40.jpg

F/Lt. I. R. Gleed, 87 Squadron, 18 May 1940
http://www.wwiiaircraftperformance.o...ed-18may40.jpg

F/Lt. I. R. Gleed, 87 Squadron, 19 May 1940
http://www.wwiiaircraftperformance.o...ed-19may40.jpg

P/O R. P. Beamont, 87 Squadron, 15 May 1940
http://www.wwiiaircraftperformance.o...nt-15may40.jpg

P/O F. B. Sutton, 56 Squadron, 18 May 1940
http://www.wwiiaircraftperformance.o...utton-pg80.jpg

P/O Roger Hall, 152 Squadron, 4 September 1940
http://www.spitfireperformance.com/152-hall-pg86.jpg

P/O G. Page, 56 Squadron, July 1940
http://www.wwiiaircraftperformance.o...age-july40.jpg

In some cases, in different recounting of the same event, the pilots mentioned +12 lb. boost and boost cut-out/emergency interchangeably:

P/O Colin Gray (NZ), No. 54 Squadron, 25 May 1940
http://www.spitfireperformance.com/5...-25may40-2.jpg

P/O Colin Gray (NZ), No. 54 Squadron, 25 May 1940
http://www.spitfireperformance.com/54-gray-25may40.jpg


F/LT Brian Lane, 19 Squadron, 26 May 1940
http://www.spitfireperformance.com/1...-26may40-2.jpg

F/LT Brian Lane, 19 Squadron, 26 May 1940
http://www.spitfireperformance.com/lane-26-5-40.jpg

Unless they are one of your 16 squadrons, after all, how can you prove they weren't. As I mentioned before following your logic they probably were.

The RAF training manual quote only mentions the use of boost control cut-out to obtain maximum permissible take-off boost. In case of the Merlin II/III this boost is +6.25 which is obtainable without cut-out.
The maximum permissible boost with 87 octane is documented since 1938 to be +6.25 and since January 1939 it is documented that in excess of this boost 100 octane must be used. The later documents are perfectly in line with the regulations.

This leaves the following explanations for the mentioning of use of boost control cut-out:
a) there was a failure in boost control and the cut-out is used to maintain a boost below +6.25, this doesn't provide any information about the fuel used as it could happen with 87 octane or 100 octane.
b) a boost in excess of +6.25 was used, either for take-off or combat/emergency, this is a proof for the use of 100 octane fuel or the proof for violating the maximum permissible boost.
c) a boost below +6.25 was used and the boost control was disabled without any logical reason and this boost was kept manually by the pilot below +6.25. Again no indicator for the fuel used.

Reason c) is highly unlikely as this would be a violation of the handling guidelines outlined in RAF Flying Training Manual ("This must only be used in emergency and not, in any circumstances, for ordinary flying, ... even if the correct boost is not exceeded") without any benefit.
In most cases reason a) can be ruled out by the context, in case of engine control failure the pilot would try to return to the airfield and avoid any combat and most certainly mention the engine troubles in the report.

So in the remaining cases the reported use of the cut-out is:
- proof for use of 100 octane fuel
- in the other case where 87 octane fuel was used the proof for overstepping of the regular maximum permissible boost. It shows that this was physically possible (or a breakdown of the engine or evidences for detonation would be reported in context) and in addition it was either permitted or tolerated by authority (or it would be reported as a violation in the context, e.g. I'd expect this to be mentioned as one possible reason here http://www.spitfireperformance.com/dowding.pdf).

In both cases it is a proof that the performance of the engine was increase. If this is true, this renders the whole 100 octane debate obsolete as pilots would simply use the increased power if necessary independent of the used fuel.

My understanding is that this is not true.

wrong
It's not irrelevant. What you're claiming here is that every reference to those things, where there is no explicit mention of 12lb, means that we can be 100% certain that they were not referring to 12lb. This is illogical.

It's not proof of 12lb boost, but it is entirely relevant and should be investigated to determine if it is, or is not, a reference to 12lb boost, in each case.

When using emergency boost pressures in excess of 6.25 lbs/sq.in. 100 octane was required, therefore if a pilot recorded use of emergency power it necessarily follows that the aircraft was fueled with 100 octane fuel.

Operational Notes for Pilots on Merlin II and III, January 1939 (thanks 41Sqn_Banks)
http://www.wwiiaircraftperformance.o...nuary-1939.jpg

Pilot's Notes, Merlin II, III and IV, 4th Edition, April 1940, page 6.
http://www.wwiiaircraftperformance.o...erlin3-pg6.jpg

Spitfires were cleared for use of 100 octane fuel for improved take-off in September 1938 just a month after the introduction of the type into service.

http://www.wwiiaircraftperformance.o...t-approval.jpg

By 12 December 1939 100 octane fuel was approved for Spitfires, Hurricanes and Defiants.
100 Octane Fuel - Issue of.

seems like all you needed was a new set of plugs and a ground test to check smooth running when using the 100 too...

Sounds contradictory to the more doom-and-gloom scenarios presented by some thread participants...

That is true.

What does it have to do with the fact the system was used before 100 Octane was an issue?

Right. From the certificate we see that a higher boost above +6 1/2lbs was available using the system on 87 Octane.

We also have Operating Note instructions in the General Operating Notes that allow for its use.

I bet Dowding did see a large increase in motor failures.

You really don't need to do anything to the engine to run 100 Octane fuel. The engine was made for 87 Octane and can run a higher knock limited performance fuel without penalty.

100 Octane has a higher lead content so changing plugs to one that are more resistant to fouling is not a bad idea.

The engine will not see any performance gains of the additional knock limited performance without modification as instructed by RAF. Those instructions to gain that performance benefit represent major modifications and inform when those major modifications where done. Those instructions have been posted ad-nauseum in this thread.

Just out of interest...did anyone realise the use of 'boost cut out' is only authorised for use in combat 'if' 100 octane fuel is used?, this shows that 'any' combat report showing the use of boost in combat confirms the use of 100 octane.

The automatic boost control cut out was intended as a emergency measure in case of automatic boost control failure, as 41Sqn_Banks post already indicated. This would be valid independent of fuel used. The procedure would be to cut the throttle, activate the cut out, and reopen throttle until the desired boost is reached. From then on, changes in speed and altitude would cause a change in boost, which could be controlled by change of throttle or engine rpm (supercharger rpm).

The use of as an emergency boost increase was a later practice. However, unless a report makes specific mention of abc failure, there's absolutely no reason to believe it was activated for anything but a 12lbs emergency boost any time 1940 or later.

This exctract of pilots notes from NZTyphoons post seems explicit on fuel type.

The can of worms was openend by the RAF General Pilot's notes authorizing the pilot to have the option to balance his risk.

It's use would also have to be recorded as it would be obvious to anyone who examined the aircraft controls.

There is no way to tell if a pilot using it was linked to fuel.

I think this is purpose related - boost control cut out in order to increase performance. The boost control cut out as an emergency item has always been available, at least I haven't seen anything indicating Hurricanes did not have the cut out even when 100 octane fuel wasn't around. The March 39 pilot notes say that "it is intended for use should the automatic boost control fail in flight or should it be necessary in an emergency to override the automatic control for an increase of boost". First purpose would be there even if 87 octane fuel was used. I haven't seen earlier pilot notes.

So how exactly does it function? if it's a boost cut out control override how does it help if the boost cut out control has failed, surely a failed ABC is kinda overriden anyway?

A failure of the the boost control influences the opening of the throttle valve. Thus the boost can get dangerously low or way to high. The boost control cut-out gives the pilot direct control over the throttle valve.

So tell us all Crumpp, how did the RAF manage to consume 52,000 gallons of 100 Octane fuel if only a select few frontline fighter units were supposed to use it? Are you going to tell us it wasn't actually consumed but went into and administrative black hole because it wasn't actually 100 octane fuel (recognised because it was green and smelled funny) but converted back to something else and poured back into reserves was it?

What exactly was your explanation and please don't tell me to go back in the thread and look because I know you have never explained this properly.

Considering those test certificate shown earlier (one issues back in '37) clearly stating that the test engines, even using 87 octane fuel was capable of over 10 1/2 lbs boost at 3000rpm and would give about 200 extra horsepower (at the expence of engine wear and possible failure at some point) at those settings, is there any wonder that in combat situations some of the pilots would try to use it?

Even going so far (before the official modification and the introduction of 100 octane fuel) as modifying their boost cutout controls with match sticks to obtain that extra performance.

I'm sure it was the same for pilots on both sides of the Channel.

No, the engine couldn't run at 10.5lb boost with 87 octane fuel. The story about the pilot modding his engine with a match stick pertained to a Merlin III using 100 octane fuel and an unauthorised mod to obtain 16lb boost at low altitude Here's the some info on the use of 100 octane for development at RR:

RR was using 100 octane fuel for testing and development from 1937 onward:

as has been pointed out the boost over-ride needed to be modded to allow for greater than 6.25lb boost, and this was only done when 100 octane fuel was used.

This is not correct. In the unmodified condition there was no restriction of the maximum boost when the boost control cut-out was used, thus the boost could be increased to about +17 lbs at full throttle at sea level.

See:
http://forum.1cpublishing.eu/attachm...1&d=1337242614
http://www.spitfireperformance.com/spit1-12lbs.jpg

Having found a 1942 (?) copy of R A Beaumont Aeronautical Engineering: A Practical Guide for Everyone Connected with the Aero Industry (modern reprint http://www.pitstop.net.au/view/aviat...uery/plu/23199) it's interesting to read what he says about the "four degrees (types) of boost" used by British aero engines:

(1) Take-off Boost - ...an additional amount of induction-pipe pressure....accompanied by an extra richening of the mixture which prevents an unstable combustion termed detonation...(p. 105)

(2) The Rated Boost - often known as maximum climbing boost....boost pressure is reduced to a value which permits the engine to run continuously at that particular power output...(p. 105-106)

(3)Override Boost - For the greatest possible power output for take-off or emergency, an increase in pressure above the normal take-off boost is permitted on some engines. This condition is used in conjunction with a special fuel. (p. 106)

(4) Maximum Cruising Boost....

Thus it is specifically stated that override or emergency boost was used only in conjunction with a fuel that permitted the higher boost rating.

Acctualy the SIM should be: SUPERMARINE SPITFIRE: CLIFFS OF DOVER. :o I almost sure the right the devs must go to BoM. At least no spitfires there. Most of data here come only from two sources: spitfireperformance.com or from Kurfurst site. I am almost sure that the DEVS had other data, maybe from URSS evaluations of the SPITS and 109s that not exactly match the data presented here.

No Seadog, it was possible as we can see from the Operating Notes. I am sure that engine was trashed after overboosting to +16lbs but it was definately possible on 87 Octane fuel.

It definately was not good but it was possible. Pulling the tit and overboosting the engine is not proof of the use of 100 Octane fuel.

Thus the boost override could not be used in the unmodded condition since it would cause almost instant engine destruction, which is a very bad thing for pilots to do during combat...It was only after 100 octane was used that the boost override became a useful adjunct to increase low altitude performance.

Indeed. Though it was possible to use the cut-out without modification and without 100 octane, this was only allowed in case of failure of the boost control. It is clearly not allowed during combat situations. The Merlin engine manual is pretty clear about this and even put an emphasize on this restriction, as posted already:
http://forum.1cpublishing.eu/attachm...1&d=1337196053

read:
http://www.wwiiaircraftperformance.o...ne/rcw-pg6.jpg

The above story clearly pertains to an engine that was already modded for 12lb boost (and thus using 100 octane) and the match stick mod permit boost up to 18lb, and it has already been established that Hurricanes in France were using 100 octane fuel by May 1940.

Maximum boost with 87 octane was 7lb:

http://www.spitfireperformance.com/spit2pnfs3.jpg

Well a key point about the spitfireperformance website is it gives us data collected at the time in reports written at the time. It is unlikely that Russian test organisations would have got any nearer to the true performance figures than the companies building the aircraft and engines and their prime user the RAF and its test organisations.

Did the Russians ever get any Spitfire Mk1s and/or MkIIs? They did get Mk Vs and MkIXs.

IvanK supplied most, if not all, of the data for the DEVS.

Great posts Seadog.

Wrong - there are two engine tests, one on 87 Octane and one on 100 which both ran up to 10.5 lbs boost - there was no boost override used which, as Beaumont observed, required special fuel - ie: 100 Octane - to achieve. Later Merlin engines, such as the 45 series, were capable of boost override of +18 lbs but needed, and were designed to use, 100 Octane to do so. Later still +25 lbs boost could only be achieved using 150 Octane.

Where does it clearly say that?

It does not, the General Operating Notes clearly say he can use it.