Effectiveness of the P-38 (2 Viewers)

[GregP]

The problem with this 'story' is that it covers around 2 years or more and 4-5 different fuel specifications.

1940
British have got their 100 octane fuel with no less than 20% aromatics.
There are at least 16 different aromatic compounds, some more useful than others for making aviation fuel. Some are a lot more expensive than others. Some are a lot better at being 'anti-knock than others.

Now the US specified no more than 2% aromatics in their 1939-1940 fuel. A lot depends on the quality of the base stock and the amount of lead they use to raise the octane number.
Problems is without aromatics it is hard to get much over 100/100 fuel without using expensive base stocks (low production) or excessive amounts of lead which had it's own problems. However aromatics tend to dissolve US self-sealing materials and gaskets in US fuel systems. This really became a problem in early 1942 when fuel Supplied by the DEI before the teh Japanese took over had 40% aromatics.

1940/41
Has to be compatible with both US and British fuel tanks and fuel systems. It also has got to be cheap to produce and not use too much lead (trying to avoid lead fowled spark plugs for one thing). Several US engines are type tested on 100/125 fuel but it does not seem to have seen major production.
The US was working on better spark plugs from 1939 though 1941 with ceramics replacing Mica as the insulator.

1941
Sept. The US Army and Navy agree to up the limit of lead from 3 ccs per US gallon to 4 ccs per US gallon. This will allow a 25% increase in production of 100 fuel as it required a lot less alkylate or other octanes. Oct 1941 sees Sun oil agree to turn over it's cat cracking facilities for the production of 100 PN fuel.
Dec 1941/1942
Shortly after Pearl Harbor The US and the British start working on a joint fuel specification. US 100 octane is varying from 100/104 to 100/130 because they are not specifying a rich mixture response measure. British want 100/125 with a test for the rich mixture response. Some American companies had developed engines using 100/120 fuel and 100/104 was not working. British and Americans finally 'agreed' on a 100/125 joint specification only to quickly change it to 100/130.

Late 1942
to increase production of 100/130 fuel the British and Americans agree to use up to 4.6cc of lead per US gal. At the same time here was a change in the allowable amounts of some aromatics although the total amount could not exceed the 20% total. Most of the time the amount was somewhere in the mid-teens. It was this fuel that caused the problems in the P-38s in 1943. It was anticipated and samples had been supplied to engine makers for testing and Allison was working in the new intake manifold for a number of months in 1943.
Now at any given time there could be dozens if not hundreds of different 100/139 fuel blends in tanks/storage around the world. The 100/130 specification was not a recipe for an exact blend. It was performance specification for a number of things like evaporation and freezing and number of BTUS per pound of fuel and allowable gum/varnish. Some refineries changed the "mix" almost weekly depending in the available raw materials. Very early 1942 saw the US/British production exceed 2,000,000 gallons a day.
By late 1942 there was no more US 100 octane less than 2% aromatic fuel available unless in some forgotten tank/s or drums.

And by late 1942/ or early 1943 there was NO British or American fuel. There was joint fuel from a number of different suppliers and these suppliers could and did change/tweak the fuel on a nearly weekly basis to maximize production. It was quite possible to draw samples from different airfields in Britian just a few hundred miles apart and get different fuel mixes, but all would 'pass' the specification test/limits.
The late 1942 specification laid out max limits on certain things. Not all batches of fuel used the max limits of many things. A lot depended on the base stocks and not all stocks were exactly the same, not all cracked gasoline was the same, could vary octane rating by a point or 2. Refineries used the lowest amounts of a boosting materials (which were more expensive) to get the base fuel (straight run + cat cracked) up the standard needed and used enough lead to get the required performance.

The problem I have with this post is the fact that I have seen both Allison and US Government paper memos detailing the "problem" and the "fix." Joe Yancey had them in his files. Yes, there was a paragraph about what amount of lead per gallon, but I didn't look too hard at it. The real takeaway was that it was recognized there was a difference between US and British fuel, and there was acknowledgement that a fix was needed goling forward so it would not crop up again as an issue after it was "fixed."

No, I don't have a copy, and Joe has retired and moved to Arkansas with his files. You can find him in Russelville, AR if you are interested.

But all the nay-say doesn't change the fact that I saw both sides (government and Allison, not the UK) acknowledge the fact of the issue and agree that it needed to be fixed. Semi shortly after that time, it WAS fixed and didn't recur. So, either I am lying or history just meshes perfectly with my story (not very likely).

About the time it was fixed, they ALSO fixed the too-smooth intake with turbulators, and air-fuel separation never happened again, either. The turbulators were incorporated with the V-1710-61 model, used in the P-40J and forward. It was internally called the F14R engine at Allison. The turbulators were called "Madam Queen," for some reason, and were effective in reatomizing any gas that condensed or had not fully atomized in the intake. Not coincidentally, the turbulators were introduced right about when the backfire screens were deleted. Valve clearances were adjusted so any backfire didn't kill the valves. Too tight intake valves were one of the causes of backfires at that time.

Elimination of the screens added 2,400 feet to the critical altitude and 7 - 10 mph in top speed in the P-39 and P-40. It took until Sep 1942 before these manifolds were approved by Wright Field for turbosupercharged engines, with a typical delay to get into the field. Prior to that, they were used only on installations without the turbochargers. So, they could not get into P-38s until then, at the earliest.

 

[BarnOwlLover]

The problem I have with this post is the fact that I have seen both Allison and US Government paper memos detailing the "problem" and the "fix." Joe Yancey had them in his files. Yes, there was a paragraph about what amount of lead per gallon, but I didn't look too hard at it. The real takeaway was that it was recognized there was a difference between US and British fuel, and there was acknowledgement that a fix was needed goling forward so it would not crop up again as an issue after it was "fixed."

No, I don't have a copy, and Joe has retired and moved to Arkansas with his files. You can find him in Russelville, AR if you are interested.

But all the nay-say doesn't change the fact that I saw both sides (government and Allison, not the UK) acknowledge the fact of the issue and agree that it needed to be fixed. Semi shortly after that time, it WAS fixed and didn't recur. So, either I am lying or history just meshes perfectly with my story (not very likely).

About the time it was fixed, they ALSO fixed the too-smooth intake with turbulators, and air-fuel separation never happened again, either. The turbulators were incorporated with the V-1710-61 model, used in the P-40J and forward. It was internally called the F14R engine at Allison. The turbulators were called "Madam Queen," for some reason, and were effective in reatomizing any gas that condensed or had not fully atomized in the intake. Not coincidentally, the turbulators were introduced right about when the backfire screens were deleted. Valve clearances were adjusted so any backfire didn't kill the valves. Too tight intake valves were one of the causes of backfires at that time.

Elimination of the screens added 2,400 feet to the critical altitude and 7 - 10 mph in top speed in the P-39 and P-40. It took until Sep 1942 before these manifolds were approved by Wright Field for turbosupercharged engines, with a typical delay to get into the field. Prior to that, they were used only on installations without the turbochargers. So, they could not get into P-38s until then, at the earliest.

I don't know if you can answer this or not, and this can just be down to simple timing in period, but I wonder why this wasn't a (at least significant) issue in the RAF's P-40s and especially RAF tac recon P-51s (AKA Mustang Is). Especially given that the RAF tac recon units did engine modifications that initially horrified Allison as far as getting power figures out of the F3R/-39 that wouldn't be seen in production V-1710s or Merlins (RR or Packard) until 1944-45 (albeit at very low altitudes, and I'm also not counting Allison or Rolls-Royce test bench tests, like those on the Merlin 60 series in 1942 that got 2000+hp out of them for short bursts). Those planes were ridiculously fast at low alt. and it took until 75 or 80/81" HG was approved for the P-51D/K and 80/81" HG dry and 90" HG wit ADI on the P-51H and XP-82/P-82B/C/D for the Merlin Mustangs to match or exceed that speed at those low alts.(though RAF Mustang IIIs/P-51Bs used for V-1 interception did have the same performance with the same supercharger boost levels). Also allowed the Mustang I/IA, a 1942 plane, to still be relevant and effective in their role even at war's end.

Ironically, the deleting of the backfire screens did come back to haunt the V-1710 in the G-series engines for the F-82. Those engines didn't live up to earlier V-1710s in terms of the reliability and durability shown in World War II. Granted, between (from what I read) having a defense sec. who was sympathetic to GM and/or knew that jets were on the way (though it took forever for the F-89 to get sorted out and in production, when meant that the T-33 trainer version of the P-80 was developed into the F-94 as an interim night/AW fighter and the F-82 was retained for longer than expected in the same roles) and Allison having a tie-in with GE on making jet engines, there was seemingly not much incentive for Allison to fix those engines in period--the fix it seems came when those engines were used for racing years later.

 

[GregP]

I'm guessing here, but the P-40s weren;t flying at very high altitudes that fed the air-fuel separation and, at lower altitudes, running in auto-rich would likely compensate for any mixture issues. I'd say most P-40 operations were 18,000 feet and under except for very few higher-altitude excursions. I could be wrong there. I'd suspect the issue would appear in auto-lean or manual mixture settings. I've started an Allison in auto-rich on a test stand, but never in manual mixture control. Since I haven't flown as pilot-in-command (PIC) in an Allison-powered (or Merlin-powered) airplane, I have no experience with auto-lean.

On run stand, you almost always are running in auto-rich, especially for break-in. Mineral oil and rich mixtures until the rings are seated and there are some 25 or so hours on it at less than full power for longer than a few seconds.

I HAVE ridden in the back seat of a P-40N and watched the engine operation as best I could. It seemed to start and run rather normally, and never misbehaved in the slightest. Ran as smoothly as a sewing machine. VERY similar to the operation of a Merlin in a P-51D, which I have also had back seat rides in. All my warbird rides have been at lower altitudes (at or under 12,500 feet), so I have never even been close to auto-lean operation.

I'd dearly love to get some PIC time in a warbird, but my bank account isn't up to a P-40 or P-51, so it's a pipe dream.

Cheers.

 

[Shortround6]

The problem I have with this post is the fact that I have seen both Allison and US Government paper memos detailing the "problem" and the "fix." Joe Yancey had them in his files. Yes, there was a paragraph about what amount of lead per gallon, but I didn't look too hard at it. The real takeaway was that it was recognized there was a difference between US and British fuel, and there was acknowledgement that a fix was needed goling forward so it would not crop up again as an issue after it was "fixed."

No, I don't have a copy, and Joe has retired and moved to Arkansas with his files. You can find him in Russelville, AR if you are interested.

But all the nay-say doesn't change the fact that I saw both sides (government and Allison, not the UK) acknowledge the fact of the issue and agree that it needed to be fixed. Semi shortly after that time, it WAS fixed and didn't recur. So, either I am lying or history just meshes perfectly with my story (not very likely).

About the time it was fixed, they ALSO fixed the too-smooth intake with turbulators, and air-fuel separation never happened again, either. The turbulators were incorporated with the V-1710-61 model, used in the P-40J and forward. It was internally called the F14R engine at Allison. The turbulators were called "Madam Queen," for some reason, and were effective in reatomizing any gas that condensed or had not fully atomized in the intake. Not coincidentally, the turbulators were introduced right about when the backfire screens were deleted. Valve clearances were adjusted so any backfire didn't kill the valves. Too tight intake valves were one of the causes of backfires at that time.

Elimination of the screens added 2,400 feet to the critical altitude and 7 - 10 mph in top speed in the P-39 and P-40. It took until Sep 1942 before these manifolds were approved by Wright Field for turbosupercharged engines, with a typical delay to get into the field. Prior to that, they were used only on installations without the turbochargers. So, they could not get into P-38s until then, at the earliest.

To me it appears there were two fuel problems, and they were over 1 year apart.
The early problem (British 20% min and US 2% max) went away in late 1941 or early 42, before P-38s showed up in England.
The US had already agreed to use much higher amounts of aromatic compounds for 100/125 fuel and test batches should have been sent to all engine makers to try to catch problems.
The 100/125 joint specification didn't last long, a few weeks or months and was superseded by the first 100/130 specification.

I don't know if some people in the US were using "British fuel" as a shorthand for the 100/130 fuel. Or were using "British fuel" as shorthand for a blend favored by the British. Agreements on fuel were not easy. USN and US Army didn't agree on amounts of certain compounds let alone agreeing with the British. The British were pushing aromatic amines to enhance rich mixture response. Shell (British) chose monomethyl amine to concentrate on, shortened to methyl amine. This worked well in for rich mixture but gave no benefit to lean mixture, in fact it sometimes degraded lean mixture. British in early work were more interested in better rich mixture performing fuel than increase production. US was interested in lean mixture cruise so there conflicts right away. Standard Oil of California wanted to use Xylidine instead of methyl amine.
The late 1942 fuel standard for 100/130 is always listed as going to 4.6cc per US gallon for lead but other changes are not given except to say that more heavy aromatics were allowed. It was this fuel that gave the problems with the P-38s and it was anticipated that the heavier aromatics would give problems and small batches of fuel were manufactured and give to engine makers to see what problems there might be. But in short histories of fuel they never say what these heavier aromatics are. Turns out the radials with their short intakes didn't have the same problems as the Allison and British problems or lack of problems are not recorded by the most popular writer.
It was found that this type of fuel would separate out and puddle in the intake manifolds of the Allison engines and the "Madam Queen" intakes were developed to counter it, on ALL Allison engines not just the P-38s although little or no trouble seems to have occurred in service.
P-38s only operated in England for a short period of time in 1942 before going to North Africa. They didn't go back to England until the Summer of 1943.

As I have said before, by this time the US 100 octane fuel with 2% is long gone. But there was a fuel that was going to give problems in 1942/43 and it was known and things were being done, maybe not fast enough. Depending on who was writing reports/letters there may certain blend/s of fuel that some people called "British fuel".

In the US there was quite a controversy over using Xylidine and the Navy wanted no part of it. They thought that water injection was better solution than using Xylidine in the fuel to push past the 100/130 fuel limit and finally refused to accept any fuel that had Xylidine in it. The Army wanted Xylidine for liquied cooled engines and in fact even the army was not in 100% agreement. Wright field was in favor of limited use but was opposed to general use. Xylidine was used in the 100/150 fuel but not 115/145?

I am not saying there were no letters talking about "British fuel". I am not saying there were no problems with the P-38s with some of the fuel the P-38s were using in England in 1943 (or even in other places in fewer incidents). I don't know if there are not some terse notes about "Army" and "Navy" fuels floating around in late 1943/early 1944.
But what was "British fuel"? and how did it differ, especially considering all the different possible blends that could be involved.
Any P-38s, P-39s or P-40s using WEP power in the fall of 1942 (or unauthorized in mid 1942) was using 100/130 or perhaps 100/125, they sure were not using 100/100 US 1940 fuel without blowing up the engines. I am not sure anybody got the 100 octane fuel from Burma, Malaya, DEI back to lab to be tested.

I am also unclear about how re-jetting fixed the problem. I may not have the needed knowledge but doesn't jetting simply mean either leaning the mixture or richening the mixture?
Perhaps the mixture was too rich for cruise allowing the puddling to happen? But changing the jets should not stop heavier compounds from separating out or cause lead to not separate out either?

 

[Shortround6]

I don't know if you can answer this or not, and this can just be down to simple timing in period, but I wonder why this wasn't a (at least significant) issue in the RAF's P-40s and especially RAF tac recon P-51s (AKA Mustang Is). Especially given that the RAF tac recon units did engine modifications that initially horrified Allison as far as getting power figures out of the F3R/-39 that wouldn't be seen in production V-1710s or Merlins (RR or Packard) until 1944-45 (albeit at very low altitudes, and I'm also not counting Allison or Rolls-Royce test bench tests, like those on the Merlin 60 series in 1942 that got 2000+hp out of them for short bursts). Those planes were ridiculously fast at low alt. and it took until 75 or 80/81" HG was approved for the P-51D/K and 80/81" HG dry and 90" HG wit ADI on the P-51H and XP-82/P-82B/C/D for the Merlin Mustangs to match or exceed that speed at those low alts.(though RAF Mustang IIIs/P-51Bs used for V-1 interception did have the same performance with the same supercharger boost levels). Also allowed the Mustang I/IA, a 1942 plane, to still be relevant and effective in their role even at war's end.

Ironically, the deleting of the backfire screens did come back to haunt the V-1710 in the G-series engines for the F-82. Those engines didn't live up to earlier V-1710s in terms of the reliability and durability shown in World War II. Granted, between (from what I read) having a defense sec. who was sympathetic to GM and/or knew that jets were on the way (though it took forever for the F-89 to get sorted out and in production, when meant that the T-33 trainer version of the P-80 was developed into the F-94 as an interim night/AW fighter and the F-82 was retained for longer than expected in the same roles) and Allison having a tie-in with GE on making jet engines, there was seemingly not much incentive for Allison to fix those engines in period--the fix it seems came when those engines were used for racing years later.

The Allisons in 1942 were using 100/130 fuel or they would have blown up. But at the time the fuel was simply called 100 or 100 octane on the fuel placards and tank trucks and squadron accounts. To get over 70" they needed to be a very low altitudes and high speed, I am not sure a P-40 could really hit 70" with an honest gauge
The extra speed of the Mustang gave them just enough extra RAM to get into the low 70s. But they lost it at even 2000-3000ft or IF they tried to climb.
The other explanation is that they were over revving the engines, 3100-3200rpm instead of 3000rpm.

 

[BarnOwlLover]

We do have to remember that the RAF tac recon units did modify the Allisons on their Mustangs to make more power, especially at low altitudes.

Colin Ford did send me this document, though the test did max out at 60". It seems that most of the mods the RAF did was to produce (concentrate) max power at lower altitudes.

But even running 60" for 15+ minutes at a time initially horrified Allison engineers until they got reports on how effective the Mustangs were and that reliability wasn't taking a huge hit.

There is also this post that references that RAF tac recon Mustangs were running 72" hg for up to 20 minutes at a time on their modified V-1710s.

Performance modifications done at Squadron level.

I have been ready a British report from August 1943 that confirms what you said about the ruggedness of the Allison 1710-39. Instead of using 56hg the British were using 72hg for up to 20 minutes at a time without any damage to the engine. The Bearings were failing at 1500hrs on average...

ww2aircraft.net

Of course, this is sort of irrelevevant to the P-38, especially given that at least some of the engine fixes were being used by 1943.

 

[Steamed_Banana]

The famous memo sent by the US observer about the overboosting of the Allisons on the British recon Mustangs is here if anyone wants to see it

E-GEH-16

I really don't think they were boosting like this in China / Burma / India with the P-51A Mustangs. I could be wrong! But I suspect either a standardized policy had determined something closer to the 56" or 57" or 60" Hg WEP rating for boost (and limited to 5 minutes) or they weren't even doing that. Anyone have a 1944 or 1945 manual for US P-51A?

 

[GregP]

To me it appears there were two fuel problems, and they were over 1 year apart.
The early problem (British 20% min and US 2% max) went away in late 1941 or early 42, before P-38s showed up in England.
The US had already agreed to use much higher amounts of aromatic compounds for 100/125 fuel and test batches should have been sent to all engine makers to try to catch problems.
The 100/125 joint specification didn't last long, a few weeks or months and was superseded by the first 100/130 specification.

I don't know if some people in the US were using "British fuel" as a shorthand for the 100/130 fuel. Or were using "British fuel" as shorthand for a blend favored by the British. Agreements on fuel were not easy. USN and US Army didn't agree on amounts of certain compounds let alone agreeing with the British. The British were pushing aromatic amines to enhance rich mixture response. Shell (British) chose monomethyl amine to concentrate on, shortened to methyl amine. This worked well in for rich mixture but gave no benefit to lean mixture, in fact it sometimes degraded lean mixture. British in early work were more interested in better rich mixture performing fuel than increase production. US was interested in lean mixture cruise so there conflicts right away. Standard Oil of California wanted to use Xylidine instead of methyl amine.
The late 1942 fuel standard for 100/130 is always listed as going to 4.6cc per US gallon for lead but other changes are not given except to say that more heavy aromatics were allowed. It was this fuel that gave the problems with the P-38s and it was anticipated that the heavier aromatics would give problems and small batches of fuel were manufactured and give to engine makers to see what problems there might be. But in short histories of fuel they never say what these heavier aromatics are. Turns out the radials with their short intakes didn't have the same problems as the Allison and British problems or lack of problems are not recorded by the most popular writer.
It was found that this type of fuel would separate out and puddle in the intake manifolds of the Allison engines and the "Madam Queen" intakes were developed to counter it, on ALL Allison engines not just the P-38s although little or no trouble seems to have occurred in service.
P-38s only operated in England for a short period of time in 1942 before going to North Africa. They didn't go back to England until the Summer of 1943.

As I have said before, by this time the US 100 octane fuel with 2% is long gone. But there was a fuel that was going to give problems in 1942/43 and it was known and things were being done, maybe not fast enough. Depending on who was writing reports/letters there may certain blend/s of fuel that some people called "British fuel".

In the US there was quite a controversy over using Xylidine and the Navy wanted no part of it. They thought that water injection was better solution than using Xylidine in the fuel to push past the 100/130 fuel limit and finally refused to accept any fuel that had Xylidine in it. The Army wanted Xylidine for liquied cooled engines and in fact even the army was not in 100% agreement. Wright field was in favor of limited use but was opposed to general use. Xylidine was used in the 100/150 fuel but not 115/145?

I am not saying there were no letters talking about "British fuel". I am not saying there were no problems with the P-38s with some of the fuel the P-38s were using in England in 1943 (or even in other places in fewer incidents). I don't know if there are not some terse notes about "Army" and "Navy" fuels floating around in late 1943/early 1944.
But what was "British fuel"? and how did it differ, especially considering all the different possible blends that could be involved.
Any P-38s, P-39s or P-40s using WEP power in the fall of 1942 (or unauthorized in mid 1942) was using 100/130 or perhaps 100/125, they sure were not using 100/100 US 1940 fuel without blowing up the engines. I am not sure anybody got the 100 octane fuel from Burma, Malaya, DEI back to lab to be tested.

I am also unclear about how re-jetting fixed the problem. I may not have the needed knowledge but doesn't jetting simply mean either leaning the mixture or richening the mixture?
Perhaps the mixture was too rich for cruise allowing the puddling to happen? But changing the jets should not stop heavier compounds from separating out or cause lead to not separate out either?

Hi Shortround.

I would not dispute two fuel problems or even possibly another one. But it got worked out and likely disappeared as an issue after that.

The aromatics issue was early and got solved. Exact dates are not something I can positively state or argue about much, other than ± several months. I DO know that the fuel issue was solved somewhere about the same time the Allison intake issue was also solved. Only actual mission experience solved pilot inexperience, and the heater issue was fixed in the J series. As I said above, our P-38 is a P-38J-20-LO. So, while it has many of the J series features, it doesn't have boosted ailerons.

I also don't want to belabor the issues since they were all solved except for the low limiting Mach number. A late war P-38 was formidable, much more so than an early D of H model. In the end, it was a good fighter that could turn and roll with the best of them, was decently fast, and climbed well at high power settings. It could easily outfly a Mosquito as a pure fighter, but wasn't as adpatable to so many missions as the Mossie.

None of which is a knock against the Mosquito, which was and IS a really wonderful airplane. We are lucky enough to have one visit occasionally.

Cheers!

 

[Steamed_Banana]

I'm guessing here, but the P-40s weren;t flying at very high altitudes that fed the air-fuel separation and, at lower altitudes, running in auto-rich would likely compensate for any mixture issues. I'd say most P-40 operations were 18,000 feet and under except for very few higher-altitude excursions. I could be wrong there. I'd suspect the issue would appear in auto-lean or manual mixture settings. I've started an Allison in auto-rich on a test stand, but never in manual mixture control. Since I haven't flown as pilot-in-command (PIC) in an Allison-powered (or Merlin-powered) airplane, I have no experience with auto-lean.

They generally stayed below around 20,000 ft if possible, and below 16,000 ft was more ideal for the P-40Es and Ks (critical alt was just 12,000 feet for the V-1710-39 and 73), but sometimes the situation required they go much higher than their comfort zone. Notably for example very early on during the 49th FG defense of Darwin they were intercepting Japanese air raids at 26-28,000 ft, where they could barely fly with their P-40Es, they would just have to immediately dive if they became engaged with a fighter. This also happened a few times in China, New Guinea and the Solomons as well, basically any time the Japanese were flying in raids at high altitude, or when they had to fly over mountains etc.

The British / Commonwealth units in North Africa however rarely seem to have operated much above 10,000 ft or so, often lower than that, except with the merlin engined kittys.

The P-40M and Ns with the V-1710-81 had a critical altitude about 3,000 ft higher and were more capable up around 20,000 ft, and could probably manage to exist a bit higher than that, with the caveat that a split S and power dive down to realms where they had more credibility as military aircraft was moments away at all times.

On run stand, you almost always are running in auto-rich, especially for break-in. Mineral oil and rich mixtures until the rings are seated and there are some 25 or so hours on it at less than full power for longer than a few seconds.

I HAVE ridden in the back seat of a P-40N and watched the engine operation as best I could. It seemed to start and run rather normally, and never misbehaved in the slightest. Ran as smoothly as a sewing machine. VERY similar to the operation of a Merlin in a P-51D, which I have also had back seat rides in. All my warbird rides have been at lower altitudes (at or under 12,500 feet), so I have never even been close to auto-lean operation.

I'd dearly love to get some PIC time in a warbird, but my bank account isn't up to a P-40 or P-51, so it's a pipe dream.

Cheers.

Still, even to ride as a passenger is pretty amazing. Few will ever get to do that.

 

[Greg Boeser]

Maybe did we cross paths at Fort Bliss, I was invited at the local Rod and Gun Club in 1997.

In '97 I was attached to the Luftwaffe logistics unit up in Roswell. They were flying in to Roswell, picking up their vehicles, which had been shipped by sea, then railed up to Roswell, from where they road marched down to Ft. Bliss. Then at the end of the excercise they did the reverse. It was a lot of fun. I learned a lot. And they shared their beer ration.
One of my first duties was translating a memorandum from the German force commander to the American commander that stated that, in Germany, beer was considered an essential foodstuff, and that it would not be withheld from the troops.

 

[Steamed_Banana]

I wonder what weird conspiracy theories were cooked up if anyone saw Lufwtwaffe jets and pallets of German beer being trucked to Roswell...

 

[GregP]

They generally stayed below around 20,000 ft if possible, and below 16,000 ft was more ideal for the P-40Es and Ks (critical alt was just 12,000 feet for the V-1710-39 and 73), but sometimes the situation required they go much higher than their comfort zone. Notably for example very early on during the 49th FG defense of Darwin they were intercepting Japanese air raids at 26-28,000 ft, where they could barely fly with their P-40Es, they would just have to immediately dive if they became engaged with a fighter. This also happened a few times in China, New Guinea and the Solomons as well, basically any time the Japanese were flying in raids at high altitude, or when they had to fly over mountains etc.

The British / Commonwealth units in North Africa however rarely seem to have operated much above 10,000 ft or so, often lower than that, except with the merlin engined kittys.

The P-40M and Ns with the V-1710-81 had a critical altitude about 3,000 ft higher and were more capable up around 20,000 ft, and could probably manage to exist a bit higher than that, with the caveat that a split S and power dive down to realms where they had more credibility as military aircraft was moments away at all times.



Still, even to ride as a passenger is pretty amazing. Few will ever get to do that.

I've been a volunteer at the Planes of Fame Museum for 20 years. In that time, some nice things have happened and I'm a LOT more familiar with warbirds than I ever thought I'd be.

We get a really good mix since we fly maybe 30 WWII airplanes and get many more as visitors coming through or coming into Fighter Rebuilders for maintenance. Quite a number of interesting types come through and we volunteers get to see them up close. One of the museum supporters had a P-51D and I managed to get a 2-hour ride in it once. The P-40 flight was a post landing gear maintenence test flight that lasted maybe 35 minutes. I worked on the landing gear, so I got an offer for the ride. So, one takeoff and one landing in a P-40N.

Managed 3 rides in the B-25J, and my restoration partner and I got a nice flight in the EAA Ford Trimotor. Our overriding impression , both of us, was that it took off in the same distance, climbed, cruised, and landed about like the Cherokee 180 we usually fly.

Meanwhile, we see things apart, being worked on, and sometimes get to help a bit on diverse aircraft.

Don't know whrre you are living but, if you are close to southern California, come to Chino and I'll show you around the Museum.

Cheers!

 

[Jugman]

S Shortround6
The two basic 100 octane fuels used by the US were AN-VV-F-781 and AN-F-28.

AN-VV-F-781 was introduced 9/26/1940. It had no rich rating a TEL limit of 3ml per USG and aromatics were ~4%.
Amendment 4 (11/14/1941) removed the aromatics because they were damaging fuel systems. The TEL limit was raised to 4ml.
Amendment 5 (5/13/1942) allowed aromatics again and was the first to have a rich mixture rating(125PN). There were tweaks to the distillation curves to suit the brits.

AN-F-28 replaced amendment 5 on 12/23/1942. This was the fully unified fuel grade. Rich mixture rating was raised to 130PN. Aromatics were soft caped at 20%
Amendment 2 (7/28/1943) raised the TEL to 4.6ml. This was done without the consent of the British. This created a bit of a ruckus. Sparkplug fouling was a common problem for everyone for sometime after this fuel was introduced.

 

[Steamed_Banana]

I've been a volunteer at the Planes of Fame Museum for 20 years. In that time, some nice things have happened and I'm a LOT more familiar with warbirds than I ever thought I'd be.

We get a really good mix since we fly maybe 30 WWII airplanes and get many more as visitors coming through or coming into Fighter Rebuilders for maintenance. Quite a number of interesting types come through and we volunteers get to see them up close. One of the museum supporters had a P-51D and I managed to get a 2-hour ride in it once. The P-40 flight was a post landing gear maintenence test flight that lasted maybe 35 minutes. I worked on the landing gear, so I got an offer for the ride. So, one takeoff and one landing in a P-40N.

Managed 3 rides in the B-25J, and my restoration partner and I got a nice flight in the EAA Ford Trimotor. Our overriding impression , both of us, was that it took off in the same distance, climbed, cruised, and landed about like the Cherokee 180 we usually fly.

Meanshile, we see things apart, being worked on, and sometimes get to help a bit on diverse aircraft.

Don't know whrre you are living but, if you are close to southern California, come to Chino and I'll show you around the Museum.

Cheers!

I'm not, alas, though I once was living in the LA area for work for a few years. Even saw a punk show in Chino one time (at a really crazy event called 'Pig Fest'). If I ever get out there again I'll definitely come out the Planes of Fame Museum, i didn't even know about it when I was living out there.

 

[GregP]

S Shortround6
The two basic 100 octane fuels used by the US were AN-VV-F-781 and AN-F-28.

AN-VV-F-781 was introduced 9/26/1940. It had no rich rating a TEL limit of 3ml per USG and aromatics were ~4%.
Amendment 4 (11/14/1941) removed the aromatics because they were damaging fuel systems. The TEL limit was raised to 4ml.
Amendment 5 (5/13/1942) allowed aromatics again and was the first to have a rich mixture rating(125PN). There were tweaks to the distillation curves to suit the brits.

AN-F-28 replaced amendment 5 on 12/23/1942. This was the fully unified fuel grade. Rich mixture rating was raised to 130PN. Aromatics were soft caped at 20%
Amendment 2 (7/28/1943) raised the TEL to 4.6ml. This was done without the consent of the British. This created a bit of a ruckus. Sparkplug fouling was a common problem for everyone for sometime after this fuel was introduced.

I'd bet this fuel was the one requiring the escorts to go to higher power for 15 minutes every hour to avoid plug fouling at economy cruise. So, theya ccelerated and di big S-turns over the bombers instead of slow S-turns at lower speed.

 

[GregP]

I'm not, alas, though I once was living in the LA area for work for a few years. Even saw a punk show in Chino one time (at a really crazy event called 'Pig Fest'). If I ever get out there again I'll definitely come out the Planes of Fame Museum, i didn't even know about it when I was living out there.

Well. it's been around since about 1950 - 1951, but they didn't exactly advertise a lot for many years.

Anyway, cheers, Steamed Banana. Hope to see you there sometime.

Our airshow these days is called "Central Coast Airfest," and is held in Santa Maria, where the museum is moving to in the 2030 - 2032 timeframe.

The first phase of the new facility is underway. When it gets finished. many or even most of the flying airplanes will move there, assuming they all fit.

The static airplanes will wait for the second hangar or maybe the third. I'm not even sure if the flying airplanes will all fit into the first hangar as I'm not on the museum board and don't get into the meetings. But the San Bernardino county airport authority is not really interested in keeping the museum in Chino. They'd rather have hangars where jets can bring in money to the airport. Not sure why, but the new blood seemingly would rather see a static jet than a flying WWII airplane. Many modern kids feel the same. They don't really connect with the old airplanes and don't much care about them. To them, an airplane from Viet Nam is too old to care about. So, almost none care to watch a Soviet MiG-15 bis fly. The people thath DO care are older than the kids by a couple of decades.

Which is too bad. Almost nobody can afford to operate a newer jet fighter. Finding parts for an F-86 is one thing. Try finding parts that a civilian can buy for an F-4, F-16, or F-18! The best you can hope for is maybe an A-4 Skyhawk, which is more expensive to operate than an F-86. I don't think many museums can afford to operate one very often. I could be wrong there.

 

[Steamed_Banana]

Well. it's been around since about 1950 - 1951, but they didn't exactly advertise a lot for many years.

Anyway, cheers, Steamed Banana. Hope to see you there sometime.

Our airshow these days is called "Central Coast Airfest," and is held in Santa Maria, where the museum is moving to in the 2030 - 2032 timeframe.

The first phase of the new facility is underway. When it gets finished. many or even most of the flying airplanes will move there, assuming they all fit.

The static airplanes will wait for the second hangar or maybe the third. I'm not even sure if the flying airplanes will all fit into the first hangar as I'm not on the museum board and don't get into the meetings. But the San Bernardino county airport authority is not really interested in keeping the museum in Chino. They'd rather have hangars where jets can bring in money to the airport. Not sure why, but the new blood seemingly would rather see a static jet than a flying WWII airplane. Many modern kids feel the same. They don't really connect with the old airplanes and don't much care about them. To them, an airplane from Viet Nam is too old to care about. So, almost none care to watch a Soviet MiG-15 bis fly. The people thath DO care are older than the kids by a couple of decades.

Damn, that is sad to hear. I think we need better historical airplane video games to revive the interest.

Which is too bad. Almost nobody can afford to operate a newer jet fighter. Finding parts for an F-86 is one thing. Try finding parts that a civilian can buy for an F-4, F-16, or F-18! The best you can hope for is maybe an A-4 Skyhawk, which is more expensive to operate than an F-86. I don't think many museums can afford to operate one very often. I could be wrong there.

Interesting...

 

[Frog]

Well. it's been around since about 1950 - 1951, but they didn't exactly advertise a lot for many years.

Anyway, cheers, Steamed Banana. Hope to see you there sometime.

Our airshow these days is called "Central Coast Airfest," and is held in Santa Maria, where the museum is moving to in the 2030 - 2032 timeframe.

The first phase of the new facility is underway. When it gets finished. many or even most of the flying airplanes will move there, assuming they all fit.

The static airplanes will wait for the second hangar or maybe the third. I'm not even sure if the flying airplanes will all fit into the first hangar as I'm not on the museum board and don't get into the meetings. But the San Bernardino county airport authority is not really interested in keeping the museum in Chino. They'd rather have hangars where jets can bring in money to the airport. Not sure why, but the new blood seemingly would rather see a static jet than a flying WWII airplane. Many modern kids feel the same. They don't really connect with the old airplanes and don't much care about them. To them, an airplane from Viet Nam is too old to care about. So, almost none care to watch a Soviet MiG-15 bis fly. The people thath DO care are older than the kids by a couple of decades.

Which is too bad. Almost nobody can afford to operate a newer jet fighter. Finding parts for an F-86 is one thing. Try finding parts that a civilian can buy for an F-4, F-16, or F-18! The best you can hope for is maybe an A-4 Skyhawk, which is more expensive to operate than an F-86. I don't think many museums can afford to operate one very often. I could be wrong there.

 

[BarnOwlLover]

Sadly, that means at just under 40 years old I'm sort of a youngster LOL. And the closest museum dedicated to aviation to me is the NMUSAF at Wright Patterson AFB in Dayton, and that's a 4 hour drive.

Also ironic is that I tend to collect physical media of (among other things) World War II aviation, though there I'm hoping to add to that digital stuff from some archives.

 

[Steamed_Banana]

We used to have air shows with a lot of Warbirds around here until pretty recently. They seemed to draw huge crowds but for some (to me) inexplicable reason they stopped doing them after what seemed like several great years. I really miss them. There is still one at a navy base not too far a way but it's much less accessible to me and it's mostly modern jets flying.