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TomTom222
04-13-2005, 12:50 PM
Does anyone have any info on the availability of high octane (aviation) fuel in Britain during the war, was Britain refining its own 100 - 150 octane fuel during this time?

TomTom222
04-13-2005, 12:50 PM
Does anyone have any info on the availability of high octane (aviation) fuel in Britain during the war, was Britain refining its own 100 - 150 octane fuel during this time?

TomTom222
04-13-2005, 01:24 PM
Interesting Titbit from here
http://www.localcolorart.com/search/encyclopedia/Gasoline/#World_War_II_and_octane


World War II and octane

One interesting historical issue involving octane rating took place during WWII. Germany received nearly all her oil from Romania, and set up huge distilling plants in Germany to produce petrol from coal. In the US the oil was not "as good" and the oil industry instead had to invest heavily in various expensive boosting systems. This turned out to be a huge blessing in disguise. US industry was soon delivering fuels of ever-increasing octane ratings by adding more of the boosting agents, with cost no longer a factor during wartime. By war's end American aviation fuel was commonly 130 to 150 octane, which could easily be put to use in existing engines to deliver much more power by increasing the compression delivered by the superchargers. The Germans, relying entirely on "good" petrol, had no such industry, and instead had to rely on ever-larger engines to deliver more power.

However, someone pointed out that: German aviation engines were of the direct fuel injection type and could use emergency methanol-water and nitrous-oxide injection, which gave 50% more engine power for 5 minutes of dogfight. This could be done only five times and then the aero engine went to the scrapyard (or after 40 hours run-time, whichever came first). Most German aero engines used 87 octane fuel (called B4), some high-powered engines used 100 octane (C2/C3)fuel.

Another pointed out in reply that: This historical "issue" is based on a very common misapprehension about wartime fuel octane numbers. There are two octane numbers for each fuel, one for lean mix and one for rich mix, rich being always greater. So, for example, a common British aviation fuel of the later part of the war was 100/125. The misapprehension that German fuels have a lower octane number (and thus a poorer quality) arises because the Germans quoted the lean mix octane number for their fuels while the Allies quoted the rich mix number for their fuels. Standard German high-grade aviation fuel used in the later part of the war (given the designation C3) had lean/rich octane numbers of 100/130. The Germans would list this as a 100 octane fuel while the Allies would list it as 130 octane.

After the war the US Navy sent a Technical Mission to Germany to interview German petrochemists and examine German fuel quality, their report entitled "Technical Report 145-45 Manufacture of Aviation Gasoline in Germany" chemically analysed the different fuels and concluded "Toward the end of the war the quality of fuel being used by the German fighter planes was quite similar to that being used by the Allies".

Fehler
04-14-2005, 03:05 AM
A misconception about octane rating in fuel is that the higher the octane, the better an engine will run.

This is quite misleading and here is why...

The higher the octane rating, the higher the compression that can be used in the combustion chamber to get more horse power. If an engine is rated for say 87 octane (Common regular unleaded pump gas) then it will not run better automatically with higher rated gas. Compression could be increased with different pistons, head or block decking, etc. but adding better gas will not make it run better by itself alone.

So, a P-51 with X amount of boost on 100 octane gas will not be faster by simply adding 150 octane gas, assuming that the engine is designed to run on 100 gas.

I honestly do not know the typical avaition engine compression ratio, but looking at typical 70's American muscle cars as an example a person can get quite a good illustration on how this works. A typical early 70's musclecar ran on 92 octane leaded gas and commonly ran 9.5:1 compression ratio from the factory. With the advent of unleaded 87 octane gas in the mid/late 70's, compression ratio was reduced from the factory to avoid pre-detonation. (Lower octane gas can detonate prematurely due to hot spots in the combustion chamber - thus the clanking you hear is actually your valves being slammed back into their seats by the detonation) - Not good for long term cylinder head wear! http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif Hardened valve seats were also necessary, but that was because of the cooling and lubrication properties of the lead in the gasoline prior to the "Enviromentally friendly" unleaded gas.

There are of course other things that can cause pre-detonation like poor valve timing, but you get the point.

Better gas allows manufacturers to get better performance from better designed engines. But if you take some AVGAS right now and put it in your car that is designed to run on 87 octane pump gas, you will receive no noticable difference, except in your pocketbook because AVGAS is much more expensive... http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

Waldo.Pepper
04-14-2005, 03:19 AM
It is amazing what the Japanese tried to/had to run their planes on toward the end.

hop2002
04-14-2005, 03:27 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Does anyone have any info on the availability of high octane (aviation) fuel in Britain during the war, was Britain refining its own 100 - 150 octane fuel during this time? <HR></BLOCKQUOTE>

Standard aviation fuel in Britain in the 30s was 87 octane.

In tne late 30s, the RAF began to investigate the use of 100 octane, and started buying supplies of it in 1937. They built up a sizeable stockpile before releasing it for use, in March 1940.

By early November 1940, just after the Battle of Britain had finished, that stockpile stood at 500,000 tons in the UK. The report in Nov 1940 says that the reserve was sufficient for 80 weeks consumption at present levels, and then goes on to defend the size of the reserve, and points out it could be used after the war as well, so there was obviously some concern they would be criticised for having too much 100 octane fuel.

As to sources of this fuel, there were 3 major British refineries producing high octane aviation fuel, Heysham, Billingham and Stanlow (Stanlow only later in the war, I believe). The capacity of 100 octane fuel at Heysham in early 1941 was 150,000 tons a year. Large amounts were also imported from the US, the Caribbean, Middle East, and I think Dutch East Indies.

In 1943 the British began producing 100/150 octane fuel, which went into full scale production in 1944. This fuel was only produced in Britain. (America had plans to produce 115/145 during the war, but the pressures on production of 100/130 meant that 115/145 didn't reach production during the war, and it was only produced and used for testing)

The British production figures (courtesy Neil Sterling, as most of this stuff is)
First number is 100/150 fuel, second 100/130, US barrels:

March 44, 221400----138400
April 44, 315400----137700
May 44, 43800----471000
June 44, 71400----340700
July 44, 217300----118100
August 44, 344800----136000
September 44, 278900----143200
October 44, 316800----159200
November 44, 214700----211100
January 45, 294800----184900
Febuary 45, 284300----84300
March 45, 298000----127200
April 45, 209500----219300

Badsight.
04-14-2005, 03:30 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Waldo.Pepper:
It is amazing what the Japanese tried to/had to run their planes on toward the end. <HR></BLOCKQUOTE>different Japanese forces had 100 octane right up to WW2's end

mainly Home defense forces in the last year

Badsight.
04-14-2005, 03:39 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Fehler:
A misconception about octane rating in fuel is that the higher the octane, the better an engine will run. <HR></BLOCKQUOTE>actually , that is true , higher octane fuel helps make motors run smoother , rev crisper & idle nicer

performance tho , isnt boosted just by adding higher grade fuel , but running operation is . of course , the motor your about to run on has to be able to handel burning higher octane gas , hardened valve seats as you mentioned is the main thing needed

mynameisroland
04-14-2005, 04:56 AM
There is an article in this months Aeroplane magazine which covers the development of the DB series engines in WW2. It states that DB was hamstrung by having to us lower grade fuel - 87 octane B4 instead of C3 100 octane - this was always used in the BMW 801. The RLM ordered Daimler Benz to continue with B4 as its engines still produced respectable results with this fuel.

It was this fuel restriction which led to the development of MW 50 boosting system in the DB series engine. In order to achieve desired HP levels an extra boosting device had to be used because good high octane supplies were insufficient.

An interesting point mentioned in the article was that the DB605 in German service produced 1450 hp with B4 fuel with no Mw50. The exact same engine in Swedish service using 100 octane fuel produced 1700 hp with only one adjustment to the boost settings of the engine to allow it to operate at higher ATA levels. The DB 605 was designed to run at higher ATA levels but was always restricted to the quality of fuel available to it in German service.

TomTom222
04-14-2005, 07:13 AM
Thanks for the very full and informative reply hop, this paragraph:

In 1943 the British began producing 100/150 octane fuel, which went into full scale production in 1944. This fuel was only produced in Britain. (America had plans to produce 115/145 during the war, but the pressures on production of 100/130 meant that 115/145 didn't reach production during the war, and it was only produced and used for testing)

set me wondering if the US aircraft had to bring thier own fuel supplies with them when they operated from England.

p1ngu666
04-14-2005, 07:26 AM
think they could use either, probably http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif

hop2002
04-14-2005, 08:20 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>set me wondering if the US aircraft had to bring thier own fuel supplies with them when they operated from England. <HR></BLOCKQUOTE>

No, aviation fuel was one part of "reverse lend lease", whereby the British provided the Americans with stuff.

I don't know about 100/130 octane supplies, but the US consumed a large part of British 100/150 production, around 20,000 tons a month, iirc, more than the RAF were using prior to the start of 1945 (and possibly more even then)

100/130 octane fuel was produced in many parts of the world, and the distribution seems to have been to the closest geographical areas, rather than based on which country produced it. For example, fuel refined in Britain was used in Europe, fuel from the Middle East was used there and North africa (and probably Burma/China/India, etc)

A lot was also produced in the US and shipped across the Atlantic, so in that sense the US did bring at least some of their fuel with them, simply because supply from the UK alone wouldn't have been sufficient.

lrrp22
04-14-2005, 09:13 AM
VIIth Fighter Command on Iwo Jima began using 115/145 grade beginning in April of '45. Navy carrier pilots also refer to its use during the same period.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by TomTom222:
(America had plans to produce 115/145 during the war, but the pressures on production of 100/130 meant that 115/145 didn't reach production during the war, and it was only produced and used for testing)

<HR></BLOCKQUOTE>

ddsflyer
04-14-2005, 09:51 AM
To answer a few questions:
1. Higher octane will definitely NOT make an engine run any smoother unless the preignition or detonation manifold pressure/compression ratio level is reached. Then it will allow higher horespower output while preventing ping or knock. Below that level it makes no difference at all. One problem with the higher octane fuels is that they contained higher levels of tetraethyl lead which has a tendency to accumulate as deposits on the valve faces and spark plugs at low power settings causing fouling and requiring more frequent cleaning.
2. Avgas was originally made in 4 grades, each dyed a different color. Red gas was 80/87 octane. Green gas was 100/130 octand. Purple gas was 115/145 octane. All 3 were replaced in the 1980's with Blue gas which is currently in use and is rated as 100LL (low lead).

I have been flying aircraft for over 30 years and intimately involved with all of these issues.

p1ngu666
04-14-2005, 10:14 AM
in my engine book im readin, aprently 50octane was used in ww1 alot http://forums.ubi.com/images/smilies/blink.gif

hop2002
04-14-2005, 10:56 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>VIIth Fighter Command on Iwo Jima began using 115/145 grade beginning in April of '45. Navy carrier pilots also refer to its use during the same period. <HR></BLOCKQUOTE>

According to "Aviation Gasoline Production and Control",Army Air Forces Historical Study 65:

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>The Petroleum Administration for War was requested to prepare 75,000 barrels of 115/145 for engine development experiments. The War and Navy departments, however, interposed an objection. They agreed that the improvement of the fuel was emminently desireable, but the Secretaries bluntly called attention to the fact that the requirements for 130 grade had thus far not been met <HR></BLOCKQUOTE>

(This is in amongst pages detailing the production problems and shaortages of 100/130 production, and the worry about supply being able to keep up with demand)

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>During the next month, July [1944], the aviation gasoline situation became more critical than ever because of the acceleration of the war in Europe and the effort to aquire sufficient fuel for training.

It soon became evident that despite all efforts to the contrary that sufficient quantities of 115/145 grade would not be available for immediate operational purposes <HR></BLOCKQUOTE>

It moves on, still talking about production problems, to Jan 1945:

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>A campaign was being conducted for the removal of bottlenecks in the production system, but no definate plans had been made to manufacture 145 grade gasoline for operational purposes. About 75,000 barrels had been produced for development purposes in December 1944, but the requirements for 130 grade continued to exceed production <HR></BLOCKQUOTE>

And finally, in the closing paragraphs summing up the situation at the end of the war:

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>A large quantity of 115/145 grade fuel was manufactured for experimental purposes, but operational quantities were not available before the end of the war <HR></BLOCKQUOTE>

What I suspect is some of that 75,000 barels produced for testing was used for operational testing, but it's fairly clear 115/145 was not in operational use during the war.

lrrp22
04-14-2005, 01:32 PM
Major James Tapp, 78th FS/15th FG ace, referring to the 7 Apr 45 B-29 VLR escort to Japan:

"The Command [VIIth FC/20th AAF] had begun using the 115/145 Octane leaded gasoline. This caused "lead" globules to form on the spark plugs shorting them out. The loss of even one plug out of 24 made the engine run very rough. This was most disconcerting to the pilots. It was found that by running the engine at full RPM and manifold pressure periodically during the cruise portion of the mission helped greatly to prevent the fouling from occurring. It was a long enough ride home without all the problems. This first mission and those that followed averaged about seven and a half hours."

Another source refers to the use of 80" Hg Take-off and Combat power for these same VIIth FC Mustangs.

Apparently, 115/145 grade became available to some combat units sometime between Jan and April of '45.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by hop2002:

What I suspect is some of that 75,000 barels produced for testing was used for operational testing, but it's fairly clear 115/145 was not in operational use during the war. <HR></BLOCKQUOTE>

SkyChimp
04-14-2005, 09:09 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by hop2002:
What I suspect is some of that 75,000 barels produced for testing was used for operational testing, but it's fairly clear 115/145 was not in operational use during the war.
<HR></BLOCKQUOTE>

Hop, that's not all that report says. If you read the entire paragraph, the "war" is clearly the war in Germany. The same paragraph stated that with the arrival of the "one front war," high goctane fuel became available in quantity. The arrival of the "one front war" clearly means the defeat of Germany, and Japan remaining as the only exisitng enemy.

Additionally, I've personally spoken to a couple of Corsair pilots who stated that at the tail end of the war, they were supplied with limited quantities of 145 grade fuel in order to get maximum performance from their planes due to the kamikaze threat.

There is also an article available on the net written by a veteran pilot that indicates P-51s were using 145 grade on escort missions. In fact, he flew with it on escort missions.

http://members.cox.net/us.fighters/gas.jpg

JR_Greenhorn
04-15-2005, 12:23 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Fehler:
...compression ratio was reduced from the factory to avoid pre-detonation. <HR></BLOCKQUOTE>This is the second time I've seen the term "pre-detonation" used in as many days. There is no such thing as "pre-detonation" in an engine. The false term is a combination of preignition and detonation, two very different phenomena.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Fehler:
Lower octane gas can detonate prematurely due to hot spots in the combustion chamber...
<HR></BLOCKQUOTE>You are trying to describe preignition here, but preignition doesn't cause the fuel charge to detonate. Rather, the fuel charge is ignited by a hot spot before the spark plug is fired. If the fuel charge is ignited soon enough before the spark plug fires, the charge will burn and cylinder pressures will rapidly increase while the piston is still traveling up at the end of the compression stroke. You can imagine what this can do to an engine.

Detonation is the spontaneous combustion of the fuel charge. Detonation isn't caused by hot spots igniting fuel, however hot spots can contribute to the conditions that cause detonation. When detonation occurs, conditions somewhere in the cylinder are such that the fuel charge explodes instead of burning.

Recall that normal combustion involves a steady-burning flame front, ignited by the spark plug, that travels radially outward as it burns.

Detonation occurs ahead of the flame front. As the flame front travels, the fuel charge ahead of it is compressed and heated by the expansion of burning gasses behind the flame front. If the heat and pressure of the fuel charge exceed a certain threshold, the charge will explode on its own.

The explosion caused by detonation creates a shockwave in the cylinder. The pressure spike of the shockwave is transferred to the metal of the engine with an audible ping.
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Fehler:
...the clanking you hear is actually your valves being slammed back into their seats by the detonation <HR></BLOCKQUOTE>Actually, in an engine undergoing detonation, cylinder pressures would be so high before the explosion that the valves would have already been forced quite shut due to the pressure acting on their heads (the valves would have both been fully seated before any of this happened).

Engines with valves slamming shut will pound their valve seats into the head, but that doesn't have the pinging sound of detonation. Such a problem is caused by valve float, which is caused by an out of control valvetrain (usually this happens when the engine rpm exceeds what the valve springs can handle).

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Fehler:
A typical early 70's musclecar ran on 92 octane leaded gas and commonly ran 9.5:1 compression ratio from the factory. With the advent of unleaded 87 octane gas in the mid/late 70's, compression ratio was reduced from the factory to avoid pre-detonation. <HR></BLOCKQUOTE>In the early '70s, compression ratios fell to decrease combustion temperatures.

High combustion temperatures produce NOx emissions, so compression ratios were lowered in an effort to curtail NOx emissions. Of course, the result was decreased engine efficiency and increases in other emissions (such as unburned hydrocarbons, which are broken-down but not combusted fuel molecules).

When these other emissions exceeded regulations, catalytic converters were added to burn off the emissions that remained from low combustion temperatures.

In the mean time, the gasoline problems were occuring. Still, emission regulations brought compression ratios and performance down, and decreasing fuel quality and octane ratings kept it down.

hop2002
04-15-2005, 03:20 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Hop, that's not all that report says. If you read the entire paragraph, the "war" is clearly the war in Germany. The same paragraph stated that with the arrival of the "one front war," high goctane fuel became available in quantity. The arrival of the "one front war" clearly means the defeat of Germany, and Japan remaining as the only exisitng enemy. <HR></BLOCKQUOTE>

The "high octane" fuel they are refering to is 100/130, not 115/145.

What's very clear reading the document is that there was a constant struggle to produce enough fuel, and that 115/145 had to wait until there was sufficient excess capacity, which never actually seems to have materialised.

If you look at the planned and actual stock figures for the Pacific at the back, you'll see that stocks never reached the hoped for figures. And their projections were for the war to last in to 1946, and with further large reguirements for fuel.

If you go through the apendicies, it gives figures for 100/130 production, even 96 octane production, but nowhere does it give figures for 115/145 fuel. In fact, 115/145 is mentioned only a couple of times in the entire document, each time saying 115/145 production hadn't been started (apart from the 75,000 barrels).

That last paragraph summing up the situation is pretty clear:

"Hence requirements continued to outstrip production, while the need for 145 grade gasoline became more intense. A large quantity of 145 grade fuel was manufactured for experimental purposes, but operational quantities were not available before the end of the war. As late as March 1945 the daily production of 525,000 barrels of 130 grade failed to meet requirements. Then with the arrival of the one front war sufficient high test gasoline was available, and storage was arranged for it's rapid movement to the Pacific theater."

130 grade is "high test". Those are seperate sentences, they move on from talking about 115/145 (and saying it wasn't produced apart from test purposes), then they talk about 100/130 production, and supplying it to the Pacific.

Apart from that, though, you'd expect some mention of 115/145 production if it had actually started. They give extensive figures for 100/130 production at various times throughout the document, nothing on 115/145 apart from the 75,000 barrels.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Additionally, I've personally spoken to a couple of Corsair pilots who stated that at the tail end of the war, they were supplied with limited quantities of 145 grade fuel in order to get maximum performance from their planes due to the kamikaze threat. <HR></BLOCKQUOTE>

Quite possibly. 75,000 barrels would certainly allow for operational testing, and the document doesn't rule out more being produced for testing purposes. 75,000 barrels is over 3 million gallons.

SkyChimp
04-15-2005, 06:14 PM
It's difficult to say if the report really suggests the extent of 115/145 production was limited to the 75,000 barrels. The order to brew the 75,000 barrels was issued in the summer of 1944 according the footnote. Given the fact that the report is replete with references to the increased need for 115/145, and the fact that the Navy was starting to buy planes that required the fuel, I have diffuclty with the suggestion that none, other than the 75,000 barrels, was produced. 75,000 barrels wouldn't have gone very far, and given that the war was to last more than another year (since the order to produce 75,000 barrels was issued), I think it's reasonable some more must have been produced. I don't think the lack of 115/145 being mentioned in the appedices precludes that.

We do have anecdotal evidence that 115/145 grade fuel was used at least on a limited basis operationally. It's not impossible that it came from that original 75,000 barrel stock. But I think it's certainly a stretch.

p1ngu666
04-15-2005, 07:55 PM
some enterprising fellows may have got some too their little island base somehow anyways http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif