P38 at high altitude

[Balljoint]

Good reading here. Some of this I have seen before, some is new to me.
A couple of things come to mind.
First, the frozen turbo regulators. How is it the B17 engines with turbos did not seem to have these problems? Perhaps a different setup than the P38?
Second, the P38's flying in the Aleutians did not seem to have these cold temp problems. Must have been just as cold or colder. What were they doing different from the European P38's?

I think it's fair to say the round engines were better engineered than the Allisons. For instance, the simple omission of a flame arrestor would trash a turbo with a backfire in an early P-38.
As to Alaska, it's my impression that most of the action there was at relatively low altitudes. While cold, it probably wasn't 60 below. From films it appears that standing that there was standing water rather than ice on the runways.

Lindberg wasn't just an observer but manager to fly combat missions I believe.

 

[Shortround6]

A problem with first hand accounts is that they are true as far as the teller KNOWS.

I am not trying to degrade the men who served and flew these aircraft but they were not chemists or fuel specialists. They knew they had trouble with the engines, that is not in dispute. They were TOLD at the TIME that is was due to "European gasoline" and that is what they believe. That is what many of the mechanics believed. But many of these mechanics were 18-20 year old kids who had been through an Air Corp training school and maybe worked on their own car or tractor before joining the service.
They had no way of analyzing the fuel, they had no more test instruments than were in the plane and their own ears and eyes (watching the color of the exhaust flames. More difficult on a P-38 ).
Somehow the name/s of the bozos who were telling the pilots to fly at high rpm and low boost never seems to come to light, but we KNOW that the pilots were getting bogus information from someone.

Gasoline is not PURE. It can consist of over 400 different chemical compounds. Rarely, if ever, all at the same time. We speak of "Octane" which is not even a chemical compound but a family of chemical compounds. There are ( or were at the time) either 11 or 16 different "Octanes" each with slightly different properties. Even for laboratory work you had to specify which "Octane" you wanted.

In the most of the sources we see in our reading these days we just see references to "such and such" a fuel specification or at best perhaps a chart with a dozen different characteristics listed. They may include vapor pressures, gum residue, allowable lead content, allowable dye content, evaporation rates and so on.
The ones I have seen DO NOT list the chemical composition of the fuels. I am sure there were such specifications but it does people in the field very little good as they have no way of checking it.

We talk of aromatics, but again they are a family of chemical compounds and not all aromatics act the same. Cat cracked fuels behave differently than straight run fuels. depending on which oil field supplied the base stock and depending on which refinery was using which process quite a bit of adjustment was often needed to get the fuel blended to the right stage or level of performance before the lead was added.

Fuel had to be blended to meet "ALL" the specifications and meet the general guide lines. In 1943 the Allies thought there would be a shortage of 100/130 fuel and several steps were taken to stretch the supply. Adding extra lead to fuel that just missed the mark was one method. Using a different Performance Number (octane rating over 100) boosting compound was another and there were several. Triptane ( a colourless highly flammable liquid alkane hydrocarbon, isomeric with heptane, used in aviation fuel; 2,2,3-trimethylbutane. Formula: CH3C(CH3)2CH(CH3)CH3) was just one. However the use of some of these compounds in more than trace amounts could bring problems of their own.

A mechanic might know if the fuel had extra lead, if he was sharp he might recognize lead fouled plugs when they were changed and figure from the number (proportion) of lead fouled plugs changing that a recent batch of fuel had more lead than normal, but he would have no way of knowing if a new batch of fuel contained a few percent of triptane or some other compound.

Aviation "fuel" was only a few yeas old at the time, perhaps 10-15 years? WW I had been fought with straight run gasoline and nobody had any idea what octane rating it was. All they "knew" was that "Pennsylvania" gasoline blew up or wrecked engines that ran just fine of Mid East or Dutch East Indies gasoline. The tests that would enable them to figure out WHY didn't come into existence until the 1920s.

Again I am not trying to degrade the pilots or ground crews in any way, they are telling their stories as they know them. They certainly knew the effect/s of what was going on. Did they actually know the reasons? or just what they were told at the time?

 

[Aaron Brooks Wolters]

FLYBOYJ, I saw a video a month or so ago and cannot remember if it was on YouTube or not. Have been looking for it and have not found it yet but it went into great detail about his stint out there and the trouble he got in for going on missions.

 

[alejandro_]

what is the source?

The graph came from an article written by Williason Murray. What I was trying to say was that IMO P-38 had to cope with a very strong foe and tactics were not as sound as in 1944. Some of the P-38 advantages of the Lighting versus other American types were not the case when against Luftwaffe fighters.

Attrition and the Luetwaffe

 

[bob44]

Ok, a number of problems.

 

[Milosh]

If people chose to not believe it, that's their choice

So true.

 

[Aaron Brooks Wolters]

Here is the link to the documentory in wich Linberg teaches the Pacific theater pilots how to fly further on the sam amount of fuel. It's long but interesting and Linberg doesn't show up in the vid until about 30 minutes minutes into the video.
View: https://www.youtube.com/watch?v=Lf3Z7Nf2b3k