could the Allison engine have done what the Rolls Royce Merlin did?

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You may have to go deeper into the details, like different numbers or types of piston rings. Any notes on valves or valve timing. We know that the R changed to articulating connecting rods. The Merlin went back fork and blade rods.

The 1929 R had fork and blade rods, but with the increased boost and power being produced for 1931 there were issues with the rods and bearings, so an articulated rod system was developed.
 
According to Schlaifer in Development of Aircraft Engines "The 1929 engine was changed principally by the use of a higher supercharger gear ratio and a larger air intake; still more power was to be got by running the engine at higher speed. This increased output meant, however, that changes had to be made in virtually every Stressed part of the engine. It was necessary to replace the blade-and-fork with articulated rods, and salt-cooled exhaust valves were used for the first time on any Rolls Royce engine."
I should have made clear that this is describing the changes made for the 1931 race.
 
In the view of this once-upon-a-time aero engineer, the P-39 was the victim of its layout, combined with its diminutive size. The big gun and nosewheel filled the space where you would find the engine and a fuel tank. The water and oil coolers occupied the space where fuel might have been.

The XP's turbo and intercooler had no proper space; the internal ducting was cramped and the installation draggy. In retrospect the use of a turbo for the second stage of supercharging was a dismal idea given the packaging possibilities. The result of the NACA wind tunnel work was the determination that the turbo installation had to go.

At that point the world needed fighters, so the '39 went ahead despite its altitude limitations. The only remedy, the two stage Allison, was too long* for the '39's fuselage. Alas, the lack of fuel capacity limited its usefulness, although the P-40 didn't outrange it by much.

The P-63 was a larger airframe to accommodate the two stage Allison. Alas, the layout continued to limit its fuel capacity. The Kingcobra could hold its own with the Merlin Mustang, with the crucial difference of much shorter range. The Soviets loved the King because they didn't need Mustang range. The King hung on long enough in the VVS that a couple of F-80s that "accidentally" crossed the Korean border into Russia shot up an airfield staffed with P-63s---in 1950.

* a two-stage Allison was shoehorned into an XP-39E after lengthening its fuselage by 21 inches.
 
Allison especially and for very good reason.

In the spring/summer of 1939 the government owed Allison over 900,000 dollars for work already done.

It order to accept overseas orders Allison had to "forgive" (write off) the dept.

If Allison had not gotten the contract for the P-40 engines in April of 1939 there is a good chance GM would have shut down the engine division and kept the bearing division.
GM had loaned Allison about 500,000 dollars to keep the engine division open.

So Allison had already done a lot of something for nothing and had been burned badly by the government.
Allison had looked at two stage supercharging in 1938-39 but already had a number of projects in the works.

Now we get a bunch of people saying Allison should have funded two stage supercharger development themselves.
In 1939 Allison had 25 people working in the engineering dept. That includes the two men who ran the blueprint machine, the number of actual engineers was some want less.
Allison was trying to design the P-39 driveshaft and remote gearbox.
Allison was trying to finish off the pusher props, extension shafts on the Airacuda.
Allison was trying to come up with turbo version for the YP-38s.
Allison was working on the V-3420 24 cylinder engine.
Allison was trying to figure out how to mass produce the V-1710 engine, from 1931 through the end of 1939 Allison had built 78 engines.
The engineering staff was responsible for laying out the new production facilities, ordering the machine tools, designing the jigs and fixtures and designing any improvements, modifications.

Allison to government "Oh, you want a two stage supercharger in addition to all that? And you want us to pay for it until you can slip it into a future budget (but not this year?)
Ok, yeah, we will get right on that!!!!!" Don't hold your breath whispered in low tone.
According to Whitney GM started building Allison Plant No3 without a firm order from the air force
$500,000 was petty cash for GM in the 1930's. They were investing millions in all sorts of new fields. for instnce, they were about to revolutionize the small diesel with their legendary 71 series. Even though they have already invested in the development of large diesels for US submarines they were spending millions on a clean sheet design for the even more legendary EMD 567 which obliterated the steam engine. They built a brand-new plant to build diesel locomotives which at that time was a market that barely existed. There is a story in Sloanes book in which Hamilton asks for $500,000 to develop the 567 which Sloane says in his experience will not be enough.

In cars they were developing the world first mass produced automatic transmission the Hydramatic. Maurice Olley was doing seminal research on car suspensions which resulted in completely new designs. They were investing millions in new methods of constructing car bodies the revolutionary "turret top" which gave us my favorite ad of all time
 
According to Whitney GM started building Allison Plant No3 without a firm order from the air force
Did they have a letter of intent? The two could often be separated bey several months.
Or was GM reacting to the XP-40 winning the Jan 1939 fighter competition and anticipating orders?
$500,000 was petty cash for GM in the 1930's. They were investing millions in all sorts of new fields. for instnce, they were about to revolutionize the small diesel with their legendary 71 series.
I am not sure it was petty cash, GM didn't want to waste money. If they could see a market they were willing to spend money. If the market was slow materializing then they may have been more cautious. GM had built over 700 6-71 diesels in 1937, they were sticking them in boats, small locomotives, crawler tractors and trucks and buses. The potential for growth was there. Especially considering what the gasoline engine selection for such use was.
Even though they have already invested in the development of large diesels for US submarines they were spending millions on a clean sheet design for the even more legendary EMD 567 which obliterated the steam engine. They built a brand-new plant to build diesel locomotives which at that time was a market that barely existed.
and again, what was the potential market?
GM had been pushing the locomotive diesel engine for most of the 30s.
The US economic times from 1929 on affecting things quite a bit. A few existing companies withdrew from the market or became suppliers of components. The Railroads were cutting back investment but were looking for cost savings. in the mid 30s enough demonstrators had been fielded and/or enough low power switch locomotives had been built to build up demand.
The Market was there, it was well researched and in 1939-40 the order books were starting to fill up.
The War Production Board stopped a large amount of locomotive production and routed large diesels to warships. This skewed the market for diesels during the war and helped preserve the steam locomotive as did the petroleum shortage of 1942-43, a bit after the time in question but helps explain the slow growth in the diesel market during the war.

The Allison engine in 1938 and the first few months of 1939 was much more of a gamble. It had promise but it very little in the way of sales. Could the Allison break into the market against P & W, Wright, Continental and Lycoming? The last two made a range of industrial and motor vehicle engines in addition to aircraft engines.
The commercial airlines showed no sign of switching to a liquid cooled engine. The navy showed very little interest after the airships went away.
In 1938 could GM depend on the army alone to order enough engines to make Allison profitable?
 
According to Whitney GM started building Allison Plant No3 without a firm order from the air force
$500,000 was petty cash for GM in the 1930's. They were investing millions in all sorts of new fields. for instnce, they were about to revolutionize the small diesel with their legendary 71 series. Even though they have already invested in the development of large diesels for US submarines they were spending millions on a clean sheet design for the even more legendary EMD 567 which obliterated the steam engine. They built a brand-new plant to build diesel locomotives which at that time was a market that barely existed. There is a story in Sloanes book in which Hamilton asks for $500,000 to develop the 567 which Sloane says in his experience will not be enough.

In cars they were developing the world first mass produced automatic transmission the Hydramatic. Maurice Olley was doing seminal research on car suspensions which resulted in completely new designs. They were investing millions in new methods of constructing car bodies the revolutionary "turret top" which gave us my favorite ad of all time

Watching, with my father in law, a documentary about the first concrete multi lane roads in California, the camera was filming a new 1936 Chevrolet from the front as it drove along. My father in law said, "If we had roads that good, we would still be driving 36 Chevvys."
 
According to Whitney GM started building Allison Plant No3 without a firm order from the air force
$500,000 was petty cash for GM in the 1930's.
They were investing millions in all sorts of new fields. for instnce, they were about to revolutionize the small diesel with their legendary 71 series. Even though they have already invested in the development of large diesels for US submarines they were spending millions on a clean sheet design for the even more legendary EMD 567 which obliterated the steam engine. They built a brand-new plant to build diesel locomotives which at that time was a market that barely existed. There is a story in Sloanes book in which Hamilton asks for $500,000 to develop the 567 which Sloane says in his experience will not be enough.

In cars they were developing the world first mass produced automatic transmission the Hydramatic. Maurice Olley was doing seminal research on car suspensions which resulted in completely new designs. They were investing millions in new methods of constructing car bodies the revolutionary "turret top" which gave us my favorite ad of all time

$500,000 in 1938 dollars is well over 10 million in today's dollars and even though GM was a large corporation back then, this was a depression era and no big corporation was going to make an investment like this unless they are going to get a return. The individual(s) responsible for the business sector behind something like this would probably lose his/ their job(s) and wreck his/their career if this investment wasn't profitable. Just ask Alexander P. de Seversky.

In the bigger picture, once again you miss the fact that large aircraft companies normally do not risk development of a technology unless they know they have a contract in hand or they are pretty certain they can sell their product at a later date. You can't compare the manufacture of diesel engines, automatic transmissions or any other automotive products to the aviation industry of the late 1930s, especially when technology was continually expanding and the future was so uncertain.
 
The Bendix SD-400 was the Rolls Royce injection system built under license. Interesting it went on to have a long career in the big air-cooled V12s that powered the M46, 47 and 48 tanks.
Also note that the reliability of the G series engines left a lot to be desired

The highest F-series Allison V-1710 was the F32 (V-1710-119).

There was no F36R or F36L. The -143 and -145 were always G-series engines.
 
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By the time GM ponied out that initial half million for plant 3 they had invested 3.8 million in Allison. That's not including the 10 million they paid to buy Allison. Allison spent most of the 1930s in the red. Honestly I can see why Hazen and Hunt didn't push for more funding by GM. I think it's next to impossible that they would have put more into r&d.

As it was Allison probably spent more money on liquid cooled development then every other us manufacturer combined.

Two corrections
I meant Kreusser not Hunt.
GM only paid $600,000 plus an additional $200,000 for needed improvements. I'm not sure where I got $10 million from. Regardless it took Allison a decade to for net profits to equal the purchase price.
 
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Allison at the time was making decent money (or even very good money at times) making bearings.

It was the "engine division" of Allison that was in the red.

Not sure where the part of the company that built the propeller drive systems for the Akron and Macon were in the company structure?

Gone by 1938-39 or building the extension shafts for Bell Airacuda?
 
Allison at the time was making decent money (or even very good money at times) making bearings.

It was the "engine division" of Allison that was in the red.

Not sure where the part of the company that built the propeller drive systems for the Akron and Macon were in the company structure?

Gone by 1938-39 or building the extension shafts for Bell Airacuda?
Allison didn't have any internal divisions back then. They were far too small for that.
 
The shop was on Speedway row just outside the Indianapolis 500 race track, and it wasn't all that big. Allison moved to Florida after WWI, but left Norman Gillman in charge of the Indiana shop. Eddie Rickenbacker bought Allison Engines in 1927 and sold it to Fisher Brothers, who sold it to General Motors. In 1995, Allison was acquired by Rolls Royce, and they finally had a great source for main bearings that was owned by them.
 
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The shop was on Speedway row just outside the Indianapolis 500 race track, and it wasn't all that big. Allison moved to Florida after WWI, but left Norman Gillman in charge of the Indiana shop. Eddie Rickenbacker bought Allison Engines in 1927 and sold it to Fisher Brothers, who sold it to General Motors. In 1995, ALlion was acquired by Rolls Royce, and they finally had a great source for main bearings that was owned by them.
A friend of mine (and a hunting buddy) worked for, and retired from, Allison/Rolls Royce a few years back. He was a metallurgist and they kept him busy with various requirements and he did a lot of traveling for them, too.
 
Did they have a letter of intent? The two could often be separated bey several months.
Or was GM reacting to the XP-40 winning the Jan 1939 fighter competition and anticipating orders?

I am not sure it was petty cash, GM didn't want to waste money. If they could see a market they were willing to spend money. If the market was slow materializing then they may have been more cautious. GM had built over 700 6-71 diesels in 1937, they were sticking them in boats, small locomotives, crawler tractors and trucks and buses. The potential for growth was there. Especially considering what the gasoline engine selection for such use was.

and again, what was the potential market?
GM had been pushing the locomotive diesel engine for most of the 30s.
The US economic times from 1929 on affecting things quite a bit. A few existing companies withdrew from the market or became suppliers of components. The Railroads were cutting back investment but were looking for cost savings. in the mid 30s enough demonstrators had been fielded and/or enough low power switch locomotives had been built to build up demand.
The Market was there, it was well researched and in 1939-40 the order books were starting to fill up.
The War Production Board stopped a large amount of locomotive production and routed large diesels to warships. This skewed the market for diesels during the war and helped preserve the steam locomotive as did the petroleum shortage of 1942-43, a bit after the time in question but helps explain the slow growth in the diesel market during the war.
GM made the momentous decision to basically reinvent the locomotive in 1935.
In February 1935 Richard Dilworth, EMCs chief engineer, proposed the idea of a joint factory for Electro Motive and Winton to a meeting of GMs top management.
From the article "Daybreak at La Grange" in the August 1976 issue of Trains magazine:
"Dilworth reportedly told the automotive –oriented crowd that "their cars and trucks were nothing but rubber-tired toys. I told 'em that if that filled the highways solid with these toys they wouldn't be able to do a quarter of the transportation business of the country" Dilworth spoke his beliefs minus any niceties of speech, he also doubted his one-million-dollar request would be approved. In a meeting afterward with GM executives, EMC founder and president H. L. Hamilton was told to proceed with plans to proceed with plans to build a factory. He informed Dilworth that the giant automotive firm was ready to invest six million dollars in Dilworth's idea. The following month, on March 27, 1935, Hamilton and Dilworth broke ground for the plant…."

There are several things to note:
1. The locomotive market was virtually nonexistent except for diesel switchers. America's largest builder, Alco, did not produce any steam locomotives in 1934 and 35.

2. Even the diesel switcher market was minuscule. In 1930 Class 1 railroads rostered 74 diesels; in 1935 they had 113, an increase of only 29 over a period of 5 years. Sales of diesels locomotives at that time were not driven by operational efficiency but rather to meet city smoke ordinances. Kaufman Act - Wikipedia. Diesel switchers were concentrated in New York and Chicago with the steel industry acquiring quite a few. Alco had developed the modern form of the switcher in the HH600 in 1931 but had only built 13 up to 1935.

3. At this time EMC did not build anything. Engines came from Winton, electrical equipment from GE, with final assembly by the car body supplier. GM was entering a whole new world. Building a 90 ton locomotive was nothing like anything GM had done before. In Feb 1935 EMC was in the process of delivering their first 3 switchers. The first of the 5 larger boxcabs for passenger road service would not be completed until August 1935. With the odd ball double end transfer unit for the IC, that was the entire EMC production of 9 locomotives for 1935, all assembled by GE, St Louis Car or Bethlehem Steel.

4. The Winton 201A was not in any sense proven. Only a single Winton 201A in the original Zephyr had any significant running experience. The second 201A powered train set Union Pacific's M-10001 had entered service in Oct 1934 but was soon withdrawn for rebuilding. Incidentally, none of the 201A powered USN submarines been launched. Over a year later La Grange completed its first locomotive, an SC, on May 20, 1936.
The Winton 201A cannot be considered to be a successful engine. EMC and Cleveland Diesel (as Winton became known) started on clean sheet replacements well before large numbers of the 201A were in service. It was a failure in its original application with the USN repowering their submarines in 1942. The 201A powered passenger boxcabs and Es were all out of service by 1953, most "rebuilt" into 567 powered models, a short life for a locomotive. The switchers did better but again of lot of them were reengined with 567s

5. As to a large order book, GM was actually building on spec. They reduced the price of the SC from $84,000 to $70,000 on the assumption that there would be a run of 50 locomotives of the same design. They actually completed 24 by the end of 1936

6. The Pennsylvania railroad was by far the biggest in the USA. the New York Central was easy the second biggest. The next three; the Union Pacific, Southern Pacific and Sante Fe were about equal in size. The UP and Santa Fe have a few passenger trains but that was the extent of their interest. Of the 175 201A engined switchers NYC bought 7, Santa Fe 7 and the Pennsy 1. UP and SP didn't buy any. It wasn't until the war started that Sante Fe began to buy diesel locomotives in earnest. The other 4, particularly the Pennsy and NYC resisted dieselization as long as they could. While the Sante Fe embraced dieselization whole heartedly the other 4 didn't start buying diesels in significant numbers until after WWII.

.
 
Not really.

The timing was off.

Allison made the following engines

1940...........................1,149
1941............................6,402
1942.........................14,904
1943.........................21,064
1944.........................20,191

Until some point in late 1943 or 1944 Allison could not build aircraft engines fast enough. And in 1944 the US had sorted out the engines for the M4 Sherman and were retiring the the odd balls or sending them off in lend-lease Tanks.
The US Army kept the Ford V-8 and the Continental radials for themselves and sent the Diesel powered tanks to the Marine Corp (thousands of Landing craft used the same engines/fuel) and to the British and to the Soviet union.

Trying to build a V-8 or V-12 Allison in 1944/45 wasn't going to solve anything
 
GM made the momentous decision to basically reinvent the locomotive in 1935.
In February 1935 Richard Dilworth, EMCs chief engineer, proposed the idea of a joint factory for Electro Motive and Winton to a meeting of GMs top management.
From the article "Daybreak at La Grange" in the August 1976 issue of Trains magazine:
"Dilworth reportedly told the automotive –oriented crowd that "their cars and trucks were nothing but rubber-tired toys. I told 'em that if that filled the highways solid with these toys they wouldn't be able to do a quarter of the transportation business of the country" Dilworth spoke his beliefs minus any niceties of speech, he also doubted his one-million-dollar request would be approved. In a meeting afterward with GM executives, EMC founder and president H. L. Hamilton was told to proceed with plans to proceed with plans to build a factory. He informed Dilworth that the giant automotive firm was ready to invest six million dollars in Dilworth's idea. The following month, on March 27, 1935, Hamilton and Dilworth broke ground for the plant…."

There are several things to note:
1. The locomotive market was virtually nonexistent except for diesel switchers. America's largest builder, Alco, did not produce any steam locomotives in 1934 and 35.

2. Even the diesel switcher market was minuscule. In 1930 Class 1 railroads rostered 74 diesels; in 1935 they had 113, an increase of only 29 over a period of 5 years. Sales of diesels locomotives at that time were not driven by operational efficiency but rather to meet city smoke ordinances. Kaufman Act - Wikipedia. Diesel switchers were concentrated in New York and Chicago with the steel industry acquiring quite a few. Alco had developed the modern form of the switcher in the HH600 in 1931 but had only built 13 up to 1935.

3. At this time EMC did not build anything. Engines came from Winton, electrical equipment from GE, with final assembly by the car body supplier. GM was entering a whole new world. Building a 90 ton locomotive was nothing like anything GM had done before. In Feb 1935 EMC was in the process of delivering their first 3 switchers. The first of the 5 larger boxcabs for passenger road service would not be completed until August 1935. With the odd ball double end transfer unit for the IC, that was the entire EMC production of 9 locomotives for 1935, all assembled by GE, St Louis Car or Bethlehem Steel.

4. The Winton 201A was not in any sense proven. Only a single Winton 201A in the original Zephyr had any significant running experience. The second 201A powered train set Union Pacific's M-10001 had entered service in Oct 1934 but was soon withdrawn for rebuilding. Incidentally, none of the 201A powered USN submarines been launched. Over a year later La Grange completed its first locomotive, an SC, on May 20, 1936.
The Winton 201A cannot be considered to be a successful engine. EMC and Cleveland Diesel (as Winton became known) started on clean sheet replacements well before large numbers of the 201A were in service. It was a failure in its original application with the USN repowering their submarines in 1942. The 201A powered passenger boxcabs and Es were all out of service by 1953, most "rebuilt" into 567 powered models, a short life for a locomotive. The switchers did better but again of lot of them were reengined with 567s

5. As to a large order book, GM was actually building on spec. They reduced the price of the SC from $84,000 to $70,000 on the assumption that there would be a run of 50 locomotives of the same design. They actually completed 24 by the end of 1936

6. The Pennsylvania railroad was by far the biggest in the USA. the New York Central was easy the second biggest. The next three; the Union Pacific, Southern Pacific and Sante Fe were about equal in size. The UP and Santa Fe have a few passenger trains but that was the extent of their interest. Of the 175 201A engined switchers NYC bought 7, Santa Fe 7 and the Pennsy 1. UP and SP didn't buy any. It wasn't until the war started that Sante Fe began to buy diesel locomotives in earnest. The other 4, particularly the Pennsy and NYC resisted dieselization as long as they could. While the Sante Fe embraced dieselization whole heartedly the other 4 didn't start buying diesels in significant numbers until after WWII.

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Great information but what does this have to do with the development of aircraft engines during the late 1930s and the ability to gain a government contract (and hopefully get the customer to pay for R&D costs)?
 

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