P-38 with Merlin Engines
Edward L. Prichard
Motors' political influence kept the P-38 from having the wretched Allison
engines replaced by the Merlins. Is this new news? Politics and money do
not care about death. But Bodie has a tantalizing look at the Lockheed test
of a Merlin 60 powered Lightning. Think about that: Not a crappy Allison
V-1710 with its inability to handle high-altitude temperatures, forcing many
P-38's to return home before their escort mission with 8th. AF.
But--without the turbo-superchargers, and the attendant plumbing, (and
weight) and huge frontal area for air-to air intercooling....???
What I want to know is this: where is the test report of the P-38 test with
Merlins on board? That would mean no air-to air intercolers, but air to
liquid and the smoothing of the P-38 forward nacelles--increasing the
critical Mach number. And the Merlin never had a problem with high
altitude! (If only General Bullmoose would have allowed it: "What is good
for General Motors is good for the country." And thank you Al Capp.)
Did General Motors sacrifice American aviators to sell engines--and junk
engines at that--to maintain market positions? No one but a nazi-communist
would think that! Meanwhile, does anyone know where I can get a copy of the
Lockheed report on the flight tests of the Merlin-powered P-38?
C.C. Jordan
>OK. so Warren Bodie's book on the P-38 "Lightning" was right: General
>Motors' political influence kept the P-38 from having the wretched Allison
>engines replaced by the Merlins. Is this new news? Politics and money do
>not care about death. But Bodie has a tantalizing look at the Lockheed test
>of a Merlin 60 powered Lightning.
Bodie describes a Merlin powered P-38. However, no sample was ever built.
Re-read what Bodie has written. Lockheed went as far as designing an
installation package in the hope that the Brits would want to try the
conversion. They didn't and neither did the U.S. War Production Board. All
numbers cited by Bodie are PROJECTED performance figures, not actual test data.
>Think about that: Not a crappy Allison
>V-1710 with its inability to handle high-altitude temperatures, forcing many
>P-38's to return home before their escort mission with 8th. AF.
>But--without the turbo-superchargers, and the attendant plumbing, (and
>weight) and huge frontal area for air-to air intercooling....???
Crappy Allison??!! Hardly.
First off, let's look at the facts before we start making unsupportable claims.
1) When used in the Pacific and MTO, the Allison engine proved to be at
least as reliable as the Merlin 61 used in the P-51B, C, D, and K.
2) It is just as cold at 30,000 feet over Leyte as it is at 30,000 feet over
Germany in the dead of winter. So why weren't they having problems
at altitude anywhere but the ETO?. Two big reasons. Low grade fuel.
Turbocharged engines cannot survive long on 87 octane dishwater. Once
the problem was traced to poor fuel, detonation failures were non-existent.
The second problem was turbocharger/oilcooler related. It seems that the
turbos require consistant oiling or the bearings fail very quickly. Earlier
model Lighnings were mostly afflicted with this type of failure. I spoke to
a crewchief of a P-38 about a year ago. He claims that up to half of the
turbo failures were due to pilots flying at cruise setting with the cooler doors
wide open. The oil temperature would drop below recommended levels
and the viscosity would rise significantly. Worse, the pilots normally cruised
at very low MAP and relatively high RPM. This would reduce cylinder head
temps to the operational minimum. The combination of the two would almost
always lead to turbo failure. Had the pilots used high MAP / low RPM cruise
settings, cylinder head temps would have remained in the center of the gauge
and would have kept much more heat in the engine, and by extension, the oil.
Add to this the relative crudeness of 1940's turbocharger technology.
Turbocharger overspeeding was one problem that would occur. Spin too fast,
and it will eventually come apart.
As to the reduction of frontal area. Yes, a Merlin installation would be
cleaner. It would likely resemble the export model Lightning I that the Brits
ordered without the turbos. The so called' "castrated Lightnings". Except, the
thrustline was higher on the Merlin and would have required a slightly taller
nacelle. Please take note that the Merlin originally considered for the
conversion was the Merlin XX. This is the same engine that powered the
Hurricane Mk.II series. This engine was not a stellar performer above
25,000 feet. Using the Merlin 61 would have been far better. However,
this engine was not available in 1941 when Lockheed looked at the concept.
>
>What I want to know is this: where is the test report of the P-38 test with
>Merlins on board?
As stated, no test report exists because the plane was never built.
>That would mean no air-to air intercolers, but air to
>liquid and the smoothing of the P-38 forward nacelles--increasing the
>critical Mach number.
The critical Mach of the P-38 was not related to the intercooler installation.
The cleaner Brit export model had the same critical Mach as any other
variant. What limited the critical Mach was the airfoil design. This is why
the P-38 would get into compressability trouble so quickly. The dive flap
installation on later "J" models and all "L" models prevented the airflow
across the underside of the wing from reaching supersonic. This allowed
the P-38 to dive at high speed and retain control. It did not, however,
significantly raise the critical Mach. It only allowed some control within
that regime.
> And the Merlin never had a problem with high altitude!
The Merlin XX sure did ! By late 1943, all of the problems had been worked
out of the V-1710. With the introduction of the P-38L, there was no reason
to consider the Merlin. Not even the Merlin 61. Why? Because the Allison
V-1710F-30 engine handily out-performed the Merlin 61 in the Mustang
at all altitudes, and especially above 25,000 feet. The late model Allison
engines were superb. Remember, they were selected (supercharged version)
for the P-82 twin Mustang. The P-38L was making up to 1,725 hp per engine
in WEP, and at 30,000 ft, was still making 1,390 hp in Military power. Whereas,
the P-51's Merlin V-1650 was down from 1,520 hp to about 1,030 hp. At these
heights, the P-38L would simply walk away from the Mustang. We must not
forget the Allison powered P-38L could out-climb the P-51D by a factor of 30%,
at any altitude. Few aircraft, from any nation, could out-perform the P-38 above
30,000 feet. The P-47M was faster. So was the Ta-152H. But neither of these
could survive a turning fight with the P-38L, again, at any altitude.
>(If only General Bullmoose would have allowed it: "What is good
>for General Motors is good for the country." And thank you Al Capp.)
>
>Did General Motors sacrifice American aviators to sell engines--and junk
>engines at that--to maintain market positions? No one but a nazi-communist
>would think that! Meanwhile, does anyone know where I can get a copy of the
>Lockheed report on the flight tests of the Merlin-powered P-38?
Nowhere. None exists. Sorry.
However, if you really want to get you hackels up, read about the P-38K and
why the War Production Board killed it. The P-38K would have been the best
fighter available to the USAAF during the war, had it been built beyond two
prototypes. To read about this fighter, visit the "Planes and Pilots of WWII"
website at the address in my sigfile. Click on "Whatever happened to the P-38K"
on the main index page. The reluctance of the War Production Board to work
with Lockheed will make you heartsick. And could anyone hope to explain why
a second source / manufacturer for the Lightning was not in place until 1945?
Had not millions of dollars and countless manhours been wasted on useless
underachieving junkers like the Fisher XP-75, Lockheed could have built the
superlative P-38K.
You are correct, GM had / has too much clout with the Fed's procurement people.
Just think how many "real" fighters could have been made with these wasted
resources. GM should have limited itself to proven Naval aircraft, instead of
wasting taxpayers time and money on the Edsel of WWII fighters.
My best regards,
C.C. Jordan
Now online - Hawker's "storm" fighters at:
http://home.att.net/~C.C.Jordan/index.html
http://www.geocities.com/pentagon/quarters/9485/index.html
The "Planes and Pilots of WWII" website.
An online WWII aviation history magazine.
Where veterans can publish their memories
on their own webpage.Veterans are encouraged
to submit articles, stories and essays by
e-mail. Write me for details, or click on
the "Submission guidelines" link on the index
page of the website. A member of the WWII
Web-ring.
Edward L. Prichard
Thanks for the input. Although I started my request with a reference to
Warren Bodie's terrific book on the P-38 (my favorite WW2 airplane), I
should have gone into greater detail on the information I currently have
that has led me on my quest for the "P-38/Merlin Engine" report. So I am
going to do that now to see if I can get us all on the same page:
"Allied Piston Engines of World War II," Graham White, Society of
Automotive Engineers Press, 1995, is where I will start this time. White is
an M.E., Member SAE, authority on WW2 piston engines and a collector and
restorer of several engines. In chapter four, 'Rolls-Royce," page 78:
"Five early RAF Mustangs were delivered to the Rolls-Royce engine
installation at Hucknall in 1942. the Allison engines were replaced with
Merlin 65s from Spitfire Mk. IXs." (Note: 1942.)
Next, on page 92, same chapter, in a section titled "Would Haves, Could
Haves, Should Haves:" "In 1944 an eight Air Force P-38 was flown from
Bovington to Hucknall for a trial installation of single-stage two speed
Merlin XXs. Rolls-Royce test flew the aircraft a number of times
unmodified, until word came down to return the aircraft immediately! It
seems the decision was political in nature due to the fact the stop work
came from Washington. (Refs. 4.14, 4.25)" The first reference is "Birch,
David, Rolls-Royce Co. Archivist and Editor of 'Archive,' interview and
correspondence with author, 1992 - 1994. the second is...(drum roll):
Colman, P.A., "P-38 Performance Allison and Rolls-Royce Engines, Lockheed
Aircraft Corp., Burbank, Calif, 9 Feb 1944."
THIS is the report I am trying to find. It is the same report described in
Bodie's book, along with some tantalizing data tables from the report, but
alas with insufficient detail for my purposes. but note the dates: 1942,
February, 1944, and "in" 1944 (Hucknall P-38). Now to return to White in
the same paragraph: "Considering the problematic service record of the P-38
in the Eight Air Force, it seems almost criminal that politics should be
allowed to interfere with a potentially useful aircraft. Lockheed did an
extensive engineering evaluation of the P-38 powered by two-stage [!!!]
Merlins; the resulting aircraft would have been dramatically transformed in
a manner similar to the North American P-51 Mustang." Well now, a
suspicious man would look at those dates, assume the Lockheed study found
it's way to 8th. HQ, Eaker or Dolittle said "Get on this!!!" for reasons we
shall see below, P-38 goes to hucknall, GM finds out what is going on (that
is amazing in itself), General Bullmoose calls in his Congressional
delegation, and finis. Bodie, I might add, almost foams at the mouth in his
discussion of this sordid end to a wonderful new life for the P-38. I
sympathize. Now I must turn to why Eaker or Dolittle were so anxious to get
the Allisons out of the P-38s and Merlins into them, as was done with the
P-51.
>From White, again, in the chapter on Allison, chapter 4, section titled
"Two-Stage Engines," pg. 275: "The V-1710 was a mixed bag of first-class
engineering, ingenuity, and questionable design. (I am an engineer, and I
would call "questionable" design pretty crappy, but I digress.) "Forefront
among the complaints leveled against the V-1710 was its lack of altitude
performance when boosted only by the single-stage-engine-driven
supercharger...."Unfortunately, this lack of altitude performance cost
Allison dearly. The NAA P-51 business was lost, and the Lockheed P-38
business would likely have been lost, if lobbying from General Motors had
not stopped the merlin P-38 project...." " 'Too little, too late' best
characterizes the efforts by Allison to improve supercharger performance.
When rolls-Royce introduced the tow-speed, two stage
intercooled/afterecooled supercharger for the 60-series Merlin,
[operationally flying in Spitfire IXs in 1942] "the advantages of this
supercharger arrangement were apparent to all concerned. [Except GM and
Congress!]
Sidebar: The SEA has recently republished Sir Stanley Hooker's "Not Much of
An Engineer." Hooker was RR's supercharger wizard and later its jet engine
design wizard. The design and engineering details of both are covered,
along with some very good appendices of technical data. A must-have for
engine buffs.
Now we come to my final thesis: the dependence of the P-38s Allison on
turbosupercharging to get high-altitude performance was what ultimately
disqualified it from continuing as 8th. AF high-altitude escort fighter.
Back to White, same chapter, pg. 293. This piece starts with a history of
the problems with the leading edge wing intercoolers: "insufficient
intercooling...led to destructive detonation due to high charge
temperatures." [Throughout its career, Lockheed was continually redesigning
the P-38 to accommodate the V-1710s dependence on turbosupercharging because
of its lack of internal two-stage technology.] "The solution, incorporated
on P-38Js and later models was an air-to-air intercooler mounted under the
engine. A much deeper cowl resulted from this requirement....Although the
new intercooler arrangement solved the problem of high induction
temperatures, new problems surfaced. In cold climates, particularly in
Europe in over-cooling of the induction air resulted in lead-fouling
problems for the spark plugs. As much as 8 [cubic] cm per gallon of
tetraethyl were used in 115/145-PN aviation fuels during World War II;
consequently lead-scavenging additives were necessary. Bromides were the
most common lead-scavenging agents. Even with additives, low induction
temperatures would allow lead to migrate to the spark plug electrodes, which
could cause plug fouling and failure. This was one of the contributing
factors to the problems experienced by the Eight Air Force. conversely, the
P-38 was far more successful in the warmer Pacific climate where low charge
temperatures were avoided."
And why did not the Merlin 60-series suffer the same problems? Because a
two-stage liquid intercooled/aftercooled supercharger design is inherently
stable as to charge temperature! (See Hooker, for the details.) White has
more to say about other failures of the Allison, for example, the same low
temperatures caused the oil to congeal in the cooler, "resulting in oil
foaming. this could cause bearing failure and in severe cases failed
connecting rods...." (Page 295). Let's face it: a turbosupercharged
Allison was a stopgap: Better something than nothing. Give it that. but,
when better engines became available, it was indeed criminal to keep them
from being installed, and the Allisons retired to training duties on
obsolete aircraft. In a high-performance fighter, like the P-38, the
Allison was nothing but trouble.
OK. So now you ("C. C.") and other interested parties have the same data I
have. Now, again, can anyone help me find that Lockheed February, 1944?"
Thanks,
Ed
C.C. Jordan wrote in message <6r8a6h$13l6$1...@nntp6.u.washington.edu>...
Emmanuel Gustin
>restorer of several engines. In chapter four, 'Rolls-Royce," page 78:
>"Five early RAF Mustangs were delivered to the Rolls-Royce engine
>installation at Hucknall in 1942. the Allison engines were replaced with
>Merlin 65s from Spitfire Mk. IXs." (Note: 1942.)
Yes, but this was not the properly engineered installation of the
P-51B. It was an ugly stick-on job, with a large bath under the
nose. Suitable for tests, but not so good for production.
>allowed to interfere with a potentially useful aircraft. Lockheed did an
>extensive engineering evaluation of the P-38 powered by two-stage [!!!]
>Merlins; the resulting aircraft would have been dramatically transformed in
>a manner similar to the North American P-51 Mustang."
Highly unlikely: The P-51 had no turbosupercharger, so the V-1710 gave
it really poor high-atitude performance. The P-38 was not in the same
position, although the model 322 "castrated Lightning" for Britain was.
Moreover, putting scarce V-1650 engines in the P-38, which did not
really need them, would have been a "one for the price of two" policy.
These engines were better used in P-51s or even in P-40s, which DID
need them to remain competitive.
>Now we come to my final thesis: the dependence of the P-38s Allison on
>turbosupercharging to get high-altitude performance was what ultimately
>disqualified it from continuing as 8th. AF high-altitude escort fighter.
That seems unlikely, because all B-17s, B-24s and P-47s in the
8th AF had turbosupercharged engines. There certainly was no
objection against this technology. The problems were particular
to this installation, but could be solved. Certainly it is unfortunate
that Lockheed did not get it right the first time (Republic did very
well, in comparison) but probably they did not imagine that the
P-38 would become an escort fighter operating over Europe...
Originally it was designed as a high-altitude bomber interceptor
to protect the USA.
>obsolete aircraft. In a high-performance fighter, like the P-38, the
>Allison was nothing but trouble.
The V-1710 did relatively well in the P-63 and the P-82, too...
The basic design of the engine was advanced, and it did have
some advantages over the Merlin. Unfortunately Allison was a
small organisation, compared to e.g. Rolls-Royce, and not very
experienced. Engineering solutions for the V-1710's problems
were produced, but too slowly. The Merlin had its own share
of trouble, but they were dealt with remarkably swiftly.
Emmanuel Gustin
C.C. Jordan
>Dear "C.C:"
>
>Thanks for the input. Although I started my request with a reference to
>Warren Bodie's terrific book on the P-38 (my favorite WW2 airplane), I
>should have gone into greater detail on the information I currently have
>that has led me on my quest for the "P-38/Merlin Engine" report. So I am
>going to do that now to see if I can get us all on the same page:
>
>"Allied Piston Engines of World War II," Graham White, Society of
>Automotive Engineers Press, 1995, is where I will start this time. White is
>an M.E., Member SAE, authority on WW2 piston engines and a collector and
>restorer of several engines. In chapter four, 'Rolls-Royce," page 78:
>"Five early RAF Mustangs were delivered to the Rolls-Royce engine
>installation at Hucknall in 1942. the Allison engines were replaced with
>Merlin 65s from Spitfire Mk. IXs." (Note: 1942.)
>
>Next, on page 92, same chapter, in a section titled "Would Haves, Could
>Haves, Should Haves:" "In 1944 an eight Air Force P-38 was flown from
>Bovington to Hucknall for a trial installation of single-stage two speed
>Merlin XXs
I have isolated the next sentence for emphasis.
>Rolls-Royce test flew the aircraft a number of times unmodified,
Unmodified. I do believe that means that the conversion was never done.
If that is the case (and it appears so), there will be no test report other thanthe projected performance numbers published by Bodie. The comparison
table provided by Bodie is from the 1941 design analysis, not a later
evaluation. Bodie is careful to state as much.
> until word came down to return the aircraft immediately! It
>seems the decision was political in nature due to the fact the stop work
>came from Washington.
[Deleted references]
>THIS is the report I am trying to find. It is the same report described in
>Bodie's book, along with some tantalizing data tables from the report, but
>alas with insufficient detail for my purposes. but note the dates: 1942,
>February, 1944, and "in" 1944 (Hucknall P-38).
If the "Hucknall P-38" was never modified, how can there be a test report?
A quick call to Warren Bodie should resolve the issue. I will make the call
this evening.
> Now to return to White in
>the same paragraph: "Considering the problematic service record of the P-38
>in the Eight Air Force, it seems almost criminal that politics should be
>allowed to interfere with a potentially useful aircraft. Lockheed did an
>extensive engineering evaluation of the P-38 powered by two-stage [!!!]
>Merlins; the resulting aircraft would have been dramatically transformed in
>a manner similar to the North American P-51 Mustang."
There was much interest at Lockheed in the Merlin 61. Nearly everyone
wanted to make the change. However, we must not lay the blame for this
not being done only on GM. The AAF had a considerable investment in the
Allison and were not readily inclined to replace it on the P-38 line.
>Well now, a
>suspicious man would look at those dates, assume the Lockheed study found
>it's way to 8th. HQ, Eaker or Dolittle said "Get on this!!!" for reasons we
>shall see below, P-38 goes to hucknall, GM finds out what is going on (that
>is amazing in itself), General Bullmoose calls in his Congressional
>delegation, and finis. Bodie, I might add, almost foams at the mouth in his
>discussion of this sordid end to a wonderful new life for the P-38. I
>sympathize. Now I must turn to why Eaker or Dolittle were so anxious to get
>the Allisons out of the P-38s and Merlins into them, as was done with the
>P-51.
The installation of Merlins certainly was not a "field modification". It would
entail major depot level facilities and Lockheed would have to manufacture
retro kits and ship them to all the various theaters. A daunting proposition
that would consume a great deal of time and resources. In likelyhood, existing
aircraft would continue in service as built with only new fighters having the
Merlins installed.
>
>>From White, again, in the chapter on Allison, chapter 4, section titled
>"Two-Stage Engines," pg. 275: "The V-1710 was a mixed bag of first-class
>engineering, ingenuity, and questionable design. (I am an engineer, and I
>would call "questionable" design pretty crappy, but I digress.)
I have worked in design engineering for the past twenty years. The term "crappy"is not one I would use. Also, I have a problem with White's use of the term
"questionable". That is more than vague, it is beyond definition. I recall
reading a summary of the AAF's test report on a captured A6M. They used the sameundefined term ("questionable engineering") to describe the rather light weight
construction of the A6M's airframe. One can question it, but the A6M was one of
the best fighters in the world in 1941. Differing design philosophy may be
"questionable", but nothing succeeds like success.
>"Forefront
>among the complaints leveled against the V-1710 was its lack of altitude
>performance when boosted only by the single-stage-engine-driven
>supercharger...."Unfortunately, this lack of altitude performance cost
>Allison dearly.
The AAC requirements of the era did not envision the need for performance
above 20,000 feet. I believe that the XP-37, first flown in 1937, was the
first attempt to use a turbocharged V-1710 (-11) to achieve decent performance
above 20,000 feet. The engine had already existed for 5 or more years by
1937. The AAC could have specified a two speed, two supercharger at any
time. They did not. So how can White blame Allison for building what the
customer contracts for?
>The NAA P-51 business was lost, and the Lockheed P-38
>business would likely have been lost, if lobbying from General Motors had
>not stopped the merlin P-38 project...."
Once again, White lays the blame exclusively at the feet of GM. The Air Corps
was just as much to blame.
>" 'Too little, too late' best
>characterizes the efforts by Allison to improve supercharger performance.
In 1942, Allison was supplying engines to Bell that had excellent high altitude
performance. The Allison V-1710-93 made as much as 1,500 hp. The Kingcobra
(P-63) had a critical altitude of 25,000 feet. The same as the Merlin powered
P-51D. Curtiss offered to install this same engine into the P-40N. The AAF
preferred the V-1710-81 which was far inferior to the -93 in terms of
performance at higher altitudes. The P-40N had a critical altitude of about
15,000 feet.
Also, it is worth mentioning that the P-40F was equipped with the Packard
version of the Merlin XX. It was still a slug.
>When rolls-Royce introduced the tow-speed, two stage
>intercooled/afterecooled supercharger for the 60-series Merlin,
>[operationally flying in Spitfire IXs in 1942] "the advantages of this
>supercharger arrangement were apparent to all concerned. [Except GM and
>Congress!]
[snip]
>Now we come to my final thesis: the dependence of the P-38s Allison on
>turbosupercharging to get high-altitude performance was what ultimately
>disqualified it from continuing as 8th. AF high-altitude escort fighter.
>Back to White, same chapter, pg. 293. This piece starts with a history of
>the problems with the leading edge wing intercoolers: "insufficient
>intercooling...led to destructive detonation due to high charge
>temperatures."
[snip]
>In cold climates, particularly in
>Europe in over-cooling of the induction air resulted in lead-fouling
>problems for the spark plugs.
Once again, at high altitude, ones geographic location is irrelevant,
the temperature will be virtually the same anywhere on earth.
Over-cooling of carb air is easy to solve by adding some carburetor
heat. The pilot should be monitoring this.
> As much as 8 [cubic] cm per gallon of
>tetraethyl were used in 115/145-PN aviation fuels during World War II;
The only problem with White's numbers is that 115-145 avgas was not available
in Britain in 1944. You were fortunate to get 100 octane. 100-130 avgas was
encountered infrequently until late 1944.
>consequently lead-scavenging additives were necessary. Bromides were the
>most common lead-scavenging agents. Even with additives, low induction
>temperatures would allow lead to migrate to the spark plug electrodes, which
>could cause plug fouling and failure. This was one of the contributing
>factors to the problems experienced by the Eight Air Force. conversely, the
>P-38 was far more successful in the warmer Pacific climate where low charge
>temperatures were avoided."
Once again, carburetor air temperature can be regulated by the pilot. Granted,
it's primary function is to prevent ice forming in the venturis. Nonetheless, ifthe problem was know, the pilot could add some heat very easily.
As for White's comment about lower "charge temperatures" in the Pacific, this
is utter nonsense.
I've flown at 35,000 feet over Iceland and over the Caribbean. The outside air
temperature was essentially the same.
I'm going to have to get a copy of White's book.
[snip]
>White has
>more to say about other failures of the Allison, for example, the same low
>temperatures caused the oil to congeal in the cooler, "resulting in oil
>foaming. this could cause bearing failure and in severe cases failed
>connecting rods...." (Page 295).
The simple solution was to make sure the oil cooler shutter was closed when
cruising at altitude. Also, as I have said, the proper cruise power settings
were important to keeping cylinder head temps up.
>Let's face it: a turbosupercharged Allison was a stopgap:
This implies that Lockheed was waiting for some other engine. They were not.
>Better something than nothing. Give it that. but,
>when better engines became available, it was indeed criminal to keep them
>from being installed, and the Allisons retired to training duties on
>obsolete aircraft.
And replace them with what? You simply do not pull useful combat aircraft from
duty because a better variant is in production. You wait until the new aircraft
are in theater and feed them into the system as older aircraft are retired.
Besides, the Allison P-38s were getting the job done everywhere, including
the ETO.
> In a high-performance fighter, like the P-38, the
>Allison was nothing but trouble.
I just spent several hours on the telephone with a former crew chief
from the 49th FG. He worked on both P-40s and P-38s. His only complaint
centered on the extra man hours required to maintain two engines. Other than
that, he found the Allison easy to keep flying. I'm afraid your last comment is
not generally borne out by the men who maintained the aircraft.
>
>OK. So now you ("C. C.") and other interested parties have the same data I
>have. Now, again, can anyone help me find that Lockheed February, 1944?"
I don't think anyone can help you if the "Hucknall P-38" was never modified.
Try contacting Lockheed Aeronautical Systems Co. and ask to speak to someone
who maintains the company archives. If there ever was a Merlin conversion (whichI doubt), they will have the data on microfilm somewhere.
Best regards,
Bill Shatzer
In a previous article, ed...@teleport.com ("Edward L. Prichard") says:
>OK. so Warren Bodie's book on the P-38 "Lightning" was right: General
>Motors' political influence kept the P-38 from having the wretched Allison
>engines replaced by the Merlins. Is this new news? Politics and money do
>not care about death. But Bodie has a tantalizing look at the Lockheed test
>of a Merlin 60 powered Lightning. Think about that: Not a crappy Allison
>V-1710 with its inability to handle high-altitude temperatures, forcing many
>P-38's to return home before their escort mission with 8th. AF.
>But--without the turbo-superchargers, and the attendant plumbing, (and
>weight) and huge frontal area for air-to air intercooling....???
-snips-
>Did General Motors sacrifice American aviators to sell engines--and junk
>engines at that--to maintain market positions? No one but a nazi-communist
>would think that! Meanwhile, does anyone know where I can get a copy of the
>Lockheed report on the flight tests of the Merlin-powered P-38?
I can't buy this "conspiracy" theory that you seem to be weaving.
I can believe that a Merlin-powered P-38 was proposed and even
built in early 1944 and I can even believe that it was "killed"
by "orders from on high" (although I can't find any references
to this) but a General Motors/Pentagon conspiracy is certainly
not required to explain this course of events.
1) Assuming the deciscion to build a Merlin engined P-38 had been
made - where would the engines have come from? In the first
instance, they could only have come from the Packard Merlin
production for the North American P-51s. I'm not convinced
a Merlin-engined P-38 would have been the "superplane" you
seem to think it would have been but even had it fulfilled
its most optimistic expectations, it would not have been twice
as good an aircraft as the P-51. Certainly, giving up
the production of _two_ P-51s for every "super P-38" produced
would not have been a winning equation for the USAAF.
2) In the longer run, the Allison production line could have
been converted to Packard Merlin production to produce engines
for a "super P-38". That would have taken several months at
the least with significant loss of production. If the initial
"super P-38" experiment was in February, 1944 and the decision
to go with a "super P-38" was made almost immediatedly, it is
unlikely the modified production line would have been "up"
and producing engines before say June or July. The loss of
engine production for an aircraft which wouldn't even be
in production (much less actually deployed and in service)
until _after_ the Normandy invasion and the climactic air
battles of the Spring of '44 would, again, not be a winning
equation.
In any case, under the war contract rules which were in effect,
General Motors would have made every bit as much money producing
Packard Merlin engines on their Allison production line as they
did producing Allison engines there. Financially at least there
was no reason for General Motors to prefer producing one engine
of the other.
3) By the spring of 1944, it was pretty apparent that the next
generation of land based day fighters was going to be _jets_,
not some sort of "super P-38". The Meteor, Vampire, and P-59
had been test flying since the previous fall, the P-80 had
had its first several test flights and, indeed, squadron deployment
of the first Meteor squadron was to occur in May.
Development of a new piston-engined "super P-38" would make little
sense at this particular point in time, especially as the aircraft
would not even go into production (much less enter service) until
after the first jet squadrons had gone into action. Especially,
as producing a "super P-38" would have required either foregoing
production of significant numbers of effective P-51 fighters or
setting up a whole new engine production line (at significant
cost) for an engine (and aircraft) which was destined to be
obsolescent within a year.
I don't think it takes a GM/Pentagon cabal to "nix" the idea of
a "super P-38" - simple cost/benefit analysis would indicate that
developing and producing such an aircraft is unlikely to be worth
the cost. That being the case, an order nixing the expenditure of
further funds pursuing experiments on concept which is doomed
before it starts seems perfectly rational.
You might note that there were sereral other piston-engined fighter
proposals/developments which were nixed around this same time frame - the
P-40Q and the P-47J spring to mind - and presumably for the same
reasons.
Cheers and all,
--
Bill Shatzer - bsha...@orednet.org
Gavin Bailey
Jordan) wrote:
[I have almost nothing of value to add to this discussion, but....]
>The AAC requirements of the era did not envision the need for performance
>above 20,000 feet. I believe that the XP-37, first flown in 1937, was the
>first attempt to use a turbocharged V-1710 (-11) to achieve decent performance
>above 20,000 feet. The engine had already existed for 5 or more years by
>1937. The AAC could have specified a two speed, two supercharger at any
>time. They did not. So how can White blame Allison for building what the
>customer contracts for?
How many (if any) engine types existed in 1937 with two speed, two
stage supercharging? I don't think the fact that the AAC didn't
specify it is meaningful if it wasn't a viable alternative at the
time.
>Also, it is worth mentioning that the P-40F was equipped with the Packard
>version of the Merlin XX. It was still a slug.
I thought the issue was centred around the Merlin 60 series being
fitted in the P-38?
>The only problem with White's numbers is that 115-145 avgas was not available
>in Britain in 1944. You were fortunate to get 100 octane. 100-130 avgas was
>encountered infrequently until late 1944.
100 octane had been in comprehensive use in the whole of RAF Fighter
100 octane had been in comprehensive use in the whole of RAF Fighter
Command by the summer of 1940, and 150 octane was actually in
operational use in the summer of 1944.
Gavin Bailey
--
Fochinell
"Ancient Scots warcry" painted on the side of a Spitfire Mk XIV in 1944
- presumably without Air Ministry approval.
C.C. Jordan
wrote:
>On 19 Aug 1998 10:21:41 -0700, C.C.J...@Worldnet.att.net (C.C.
>Jordan) wrote:
>How many (if any) engine types existed in 1937 with two speed, two
>stage supercharging? I don't think the fact that the AAC didn't
>specify it is meaningful if it wasn't a viable alternative at the
>time.
The reference was to the availability of these engines in the early 40's.
Certainly, if the AAC had published a requirement for 2 speed, 2 stage
superchargers, the major campanies involved in aircraft engine design
would have attempted to meet the requirement.
>
>>Also, it is worth mentioning that the P-40F was equipped with the Packard
>>version of the Merlin XX. It was still a slug.
>
>I thought the issue was centred around the Merlin 60 series being
>fitted in the P-38?
Yes and no. Lockheed's original Merlin study was based upon the use of the
Merlin XX. It wasn't until later that the Merlin 61 was considered. The pint of
the statement above was that the Merlin XX was not superior to the Allison
V-1710-81 as they had about the same critical altitude.
>
>>The only problem with White's numbers is that 115-145 avgas was not available
>>in Britain in 1944. You were fortunate to get 100 octane. 100-130 avgas was
>>encountered infrequently until late 1944.
>
>100 octane had been in comprehensive use in the whole of RAF Fighter
>100 octane had been in comprehensive use in the whole of RAF Fighter
>Command by the summer of 1940, and 150 octane was actually in
>operational use in the summer of 1944.
Some time ago, I read a published AAF report on the quality of avgas available
in Britain in 1944. Sample were gathered from many bases and storage tanks.
The result, IIRC, was that the majority of the fuels sampled were actually under
100 octane.
I don't recall where I saw the report. Perhaps someone on the newsgroup could
be of assistance.
Regards,
Gregory W Shaw
> On 19 Aug 1998 10:21:41 -0700, C.C.J...@Worldnet.att.net (C.C.
> Jordan) wrote:
>
> [I have almost nothing of value to add to this discussion, but....]
>
Neither do I, C.C. has been handling it well enough up till now.
munch
>
> How many (if any) engine types existed in 1937 with two speed, two
> stage supercharging? I don't think the fact that the AAC didn't
> specify it is meaningful if it wasn't a viable alternative at the
> time.
>
None, IIRC the first 2-2 blower was in the P&W R1830 used in the F4F in
about 1940-41, before the 60 series Merlin was introduced by
Rolls-Royce.
munch P-40 Merlin stuff
Two reservations about the P-38/Merlin 60 combination that need to be
pointed out.
1) Graph the HP vs altitude for the V1710/B33 combo in the P-38J vs the
V-1650-7 Merlin in the P-51. At bomber escort altitudes the V1710/B33
was putting out 300+ hp WEP more than the V-1650-7. At any altitude
above about 10k the V1710/B33 outperformed the V-1650-7.
2) Fuel consumption, the V1650-7 burned about 30% more fuel/hp at cruise
settings than the V1710/B33 did. At escort altitudes, with Merlin in
high blower the difference would be even greater.
So, a P-38/V1650-7 would have been heavier, slower, and shorter ranged
than the P-38J. Doesn't sound like all that attractive a proposition to
me.
As C.C. has already pointed out, the P-38K was THE fighter the USAAF
should have been flying by 1944. It was a much more attractive option
than using the V1650 in the P-38; as has already been pointed out, every
P-38/Merlin meant two less P-51s. That the WPB prevented its
construction, while developing the P-75 and never getting Curtis or
Goodyear under control, was one of the WPB's greatest mistakes.
>
> >The only problem with White's numbers is that 115-145 avgas was not available
> >in Britain in 1944. You were fortunate to get 100 octane. 100-130 avgas was
> >encountered infrequently until late 1944.
>
> 100 octane had been in comprehensive use in the whole of RAF Fighter
> Command by the summer of 1940, and 150 octane was actually in
> operational use in the summer of 1944.
>
> Gavin Bailey
>
There is an anectdote in Martin Caidin's P-38 book about some P-38s
trying some 150 octane where many of them had to abort with lead-fouled
plugs. I don't want to speak for C.C. but that may be related to his
statements, ie the quality of AVGAS available in England was a problem,
even in 1944.
Greg Shaw
Bejewelled
>Merlin XX. It wasn't until later that the Merlin 61 was considered. The pint
>of
>the statement above was that the Merlin XX was not superior to the Allison
>V-1710-81 as they had about the same critical altitude.
>
A new book about the Allison V-1710, Vee's for Victory, Daniel Whitney,
Schiffer, has the details of P-38 studies with merlin XX, 61 and a hypothetical
2000hp merlin. The Merlin 61 figures come out almost the same as the P-38J. The
merlin '2000' comes out at 468 at critical alt, which I don't believe any 38
could do, being mach .71 at 36,000ft. Any attempt to add power beyond what was
available with a 38L would give the lightning 'compressibilty' problems on the
level. Would climb well though....
CC, if you haven't seen that book, check it out. It has similar comparisons of
merlin/1710 for P-63 (P-63B was going to have a merlin) and drawings of things
like V-3420 powered B-26 and P2V Neptune. Everything you needed to know about
the Allison in the typical big schiffer format. (But 60 bucks).
Adrian Camp.