jumpinjan
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H O R S E P O W E R - Wright 3350 Radial Engine
- Thread starter jumpinjan
- Start date
skywords
Donation Time
They are overhead valve but not overhead cam but they have a ring cam using tappets with rollers that ride the ring. Very simple really but when adjusting valves you have to use what they call bumping bars to depress the valve opposite of the cylinder you are adjusting to seat the ring cam against it's babbit bearing. You can see the push rod tubes in that video Jan posted. These engines are a marvel of engineering for their time, some Curtis Wright 3350's had turbo compound units. Simply put they are turbo chargers that physically put power back into the engine through a drive shaft on the rear accessory case (about 300 extra hp). My Dad flew these engines on the Lockheed 1049 Super Connie's. The throttle settings were so critical you could grenade all four engines by over boosting on take off. I have his Power accountability slide rule that he used with TWA as a flight engineer. It uses altimeter setting, pressure altitude, temperature, and humidity to give you the proper manifold pressure, brake mean effective pressure, and torq meter readings, to use on take off. The flight engineer had the throttles on take off, These guys were busy. I have a couple of friends that have their engineer rating on the Connie and I asked them one day is it hard to operate the throttles on take off. He replied " no you just push them up till you hear the captain say Holy poop then you pull them back a quarter inch"
Nickodell
Donation Time
I always thought that turbo-compound engines signaled the end of the "suck-squeeze-bang-blow" aircraft piston engine era. For those not familiar with the system, it was developed post-WWII mainly to deliver better fuel efficiency. Power recovery turbines (PRT) were inserted into the exhaust piping and geared to the engine crankshaft by fluid couplings in order to deliver more power, rather than by using the exhaust to deliver additional boost as in a turbocharger.
Such engines are "dual- or compound-expansion" ones, the first expansion being in the cylinders and the second in the PRTs. IIRC the PRTs recovered about 20 percent of the exhaust energy (between about 400 and 500 HP) that would have otherwise been wasted. I recall some USAF engine mechanics I talked to on a visit to their base in Fairford, England, in my RAF days, saying that they certainly added a useful range to the planes but had a negative effect on engine reliability. One mech told me that they called them "Parts Recovery Turbines," and other unprintable names. (The USAF were still using Connies, even in 1961. Gen. Norstadt, then NATO Supreme Commander, arrived at our base in Gaydon, Warwickshire that year on a visit, in his personal Super Connie).
Interestingly, turbocompounding was not just tried on air-cooled radials. Allison tried it on their liquid-cooled V-12 engine (the engine fitted to the first P-51s and to the P-38s and P-40s, among others) as an answer to the R-R Merlin. The turbo unit was essentially a GE turbosupercharger, fed by dual exhaust pipes, one from each cylinder bank, and driving the crankshaft through gears. In a prototype, the engine put out 2,800 hp on the dyno., (!!!, almost double the standard engine's) on 145 octane fuel at 3,200 rpm and 100 in Hg manifold pressure. However, the turbo inlet temperatures exceeded GE's maximum allowable, and I doubt if the internals would have stood up to this for long, so the engine's life would have been very short. Allison tried cooling the exhaust by increasing amounts of methanol/water injection, to the point that power began to fall off, and, finally, water injection directly into the exhaust manifold ahead of the turbo intakes, but by this time it was 1946, the military lost interest and the whole idea was dropped.
It's interesting to think that if Allison had begun the idea in the late 1930s, and possibly perfected it by 1941, the P-40s would probably have gained 75 mph extra and all the P-51s may have run with Allison engines and not Merlins. Maybe even some Mosquitos and Lancasters, too.
Such engines are "dual- or compound-expansion" ones, the first expansion being in the cylinders and the second in the PRTs. IIRC the PRTs recovered about 20 percent of the exhaust energy (between about 400 and 500 HP) that would have otherwise been wasted. I recall some USAF engine mechanics I talked to on a visit to their base in Fairford, England, in my RAF days, saying that they certainly added a useful range to the planes but had a negative effect on engine reliability. One mech told me that they called them "Parts Recovery Turbines," and other unprintable names. (The USAF were still using Connies, even in 1961. Gen. Norstadt, then NATO Supreme Commander, arrived at our base in Gaydon, Warwickshire that year on a visit, in his personal Super Connie).
Interestingly, turbocompounding was not just tried on air-cooled radials. Allison tried it on their liquid-cooled V-12 engine (the engine fitted to the first P-51s and to the P-38s and P-40s, among others) as an answer to the R-R Merlin. The turbo unit was essentially a GE turbosupercharger, fed by dual exhaust pipes, one from each cylinder bank, and driving the crankshaft through gears. In a prototype, the engine put out 2,800 hp on the dyno., (!!!, almost double the standard engine's) on 145 octane fuel at 3,200 rpm and 100 in Hg manifold pressure. However, the turbo inlet temperatures exceeded GE's maximum allowable, and I doubt if the internals would have stood up to this for long, so the engine's life would have been very short. Allison tried cooling the exhaust by increasing amounts of methanol/water injection, to the point that power began to fall off, and, finally, water injection directly into the exhaust manifold ahead of the turbo intakes, but by this time it was 1946, the military lost interest and the whole idea was dropped.
It's interesting to think that if Allison had begun the idea in the late 1930s, and possibly perfected it by 1941, the P-40s would probably have gained 75 mph extra and all the P-51s may have run with Allison engines and not Merlins. Maybe even some Mosquitos and Lancasters, too.
A guy that I used to work with spent some years working in Cummins Engine's R&D unit as a field tech. He said that Cummins tried this with their big 6 cylinder truck engine, but it was not successful. The problem was turbo life. It was thought the problem lie in trying to mate the Diesel output with the turbo. The problem being that after gearing up the Diesels rpm, you have significant rpm variations at the turbo as the 6 is not nearly as smooth as the aero engines or turbo.
He suggested they use the turbo to run an alternator and use the "juice" to run ancillaries, which on a big rig can be significant, especially if the rad fan and air compressor were electric. But the brass was interested only in output horsepower #'s.
Bill
He suggested they use the turbo to run an alternator and use the "juice" to run ancillaries, which on a big rig can be significant, especially if the rad fan and air compressor were electric. But the brass was interested only in output horsepower #'s.
Bill
skywords
Donation Time
Nick
That's funny they would inject water directly into the exhaust to try to cool the inlet temps. I think we were well on our way to a flash steam engine.
Bill
Maybe the reason the PRT did not work with the Cummins is because the rpm are changed so often. The aircraft engine drones along at constant rpm for hours on end and the throttle movements are always slow and gentle.
That's funny they would inject water directly into the exhaust to try to cool the inlet temps. I think we were well on our way to a flash steam engine.
Bill
Maybe the reason the PRT did not work with the Cummins is because the rpm are changed so often. The aircraft engine drones along at constant rpm for hours on end and the throttle movements are always slow and gentle.
mikephillips
Donation Time
Ya know Nick, if it had worked for the P-40, there might not have even been a P-51 since the main complaints about the P-40 were performance related.
Nickodell
Donation Time
Mike: The P-51 was greatly superior to the P-40 in several ways other than speed. It was the only plane in WWII able to accompany USAF day bombers to any target in Germany and fight the Luftwaffe on the way there and back, as it outflew the 109 and 190 in almost every respect. A P-40 with a mythical 2,000+ hp Allison would probably have had comparable speed with the German fighters, but not maneuverability, and certainly nothing like the range of the 51.
As you would expect with a design some 5 years younger than the P-40's, the 51 was a big advance in such areas as its laminar-flow wing. In fact, its airframe was superior to that of the contemporary Spitfire, which originally appeared at about the same time as the P-40, although later models of the Spit also adopted a laminar-flow wing.
Trivia: There has been endless speculation for the past 60+ years about how the P-38 Lightning would have performed with Merlins. In fact Rolls got hold of a 38 and were about to install some Merlins, at their experimental airfield at Hucknall, to see what resulted, the same way that they put them in five P-51s and transformed a good fighter into a superb one. However, politics had prevented Lockheed from specifying the Merlin for the P-38 (the same reason why the USAF replaced the Merlins in its Korea P-82 "Twin Mustangs" with Allisons, making the training [Merlin] version faster than the combat one), and when the Americans heard about what was going on at Hucknall they demanded the prompt return of their P-38!
Which was a pity, as it might have saved the P-38 from many of the problems they experienced, especially in the European Theater, and many brave boys' lives. Isn't it amazing that politics still carries on in wartime, and is often the main cause of a country's defeat. Political infighting between two group commanders (Air Vice Marshalls [equiv. Maj. Gen.] Park and Leigh-Mallory [cousin of the climber lost on Everest]) almost lost the Battle of Britain.
And the C-in-C of Fighter Command, Air Chief Marshall [General] Hugh Dowding, was constantly fighting with the politicians in Whitehall, even as Britain was on the brink of invasion. Dowding had made waves before the war in insisting on radar and 8-gun fighters, plus a rapid buildup of the RAF, against opposition from pacifists (sound familiar?), and in 1940 refused to send any more fighters to a lost cause in France (even though Churchill had promised them to the tottering French government). The moment Hitler decided to cancel (technically, "indefinitely postpone") it, Dowding found a letter on his desk from the Air Ministry abruptly saying that "Your services are no longer required." The one man who, more than any other, saved Britain - booted out.
Guess who got his job? Leigh-Mallory, who had been obstructive to Park, often refusing to send up his own 11 Group fighters when requested by Park, and insisting on adopting the "Big Wing" concept, which took so long to assemble that often the German planes had dropped their bombs and were well on their way home. And Park himself was shuffled off to some administrative post.
In the movie Battle of Britain, these political fights were well represented. Sir Laurence Olivier, who played Dowding so well, had spent countless hours studying film and sound recordings of the man he was about to portray, and those who had known Dowding said that his portrayal was eerily accurate.
As you would expect with a design some 5 years younger than the P-40's, the 51 was a big advance in such areas as its laminar-flow wing. In fact, its airframe was superior to that of the contemporary Spitfire, which originally appeared at about the same time as the P-40, although later models of the Spit also adopted a laminar-flow wing.
Trivia: There has been endless speculation for the past 60+ years about how the P-38 Lightning would have performed with Merlins. In fact Rolls got hold of a 38 and were about to install some Merlins, at their experimental airfield at Hucknall, to see what resulted, the same way that they put them in five P-51s and transformed a good fighter into a superb one. However, politics had prevented Lockheed from specifying the Merlin for the P-38 (the same reason why the USAF replaced the Merlins in its Korea P-82 "Twin Mustangs" with Allisons, making the training [Merlin] version faster than the combat one), and when the Americans heard about what was going on at Hucknall they demanded the prompt return of their P-38!
Which was a pity, as it might have saved the P-38 from many of the problems they experienced, especially in the European Theater, and many brave boys' lives. Isn't it amazing that politics still carries on in wartime, and is often the main cause of a country's defeat. Political infighting between two group commanders (Air Vice Marshalls [equiv. Maj. Gen.] Park and Leigh-Mallory [cousin of the climber lost on Everest]) almost lost the Battle of Britain.
And the C-in-C of Fighter Command, Air Chief Marshall [General] Hugh Dowding, was constantly fighting with the politicians in Whitehall, even as Britain was on the brink of invasion. Dowding had made waves before the war in insisting on radar and 8-gun fighters, plus a rapid buildup of the RAF, against opposition from pacifists (sound familiar?), and in 1940 refused to send any more fighters to a lost cause in France (even though Churchill had promised them to the tottering French government). The moment Hitler decided to cancel (technically, "indefinitely postpone") it, Dowding found a letter on his desk from the Air Ministry abruptly saying that "Your services are no longer required." The one man who, more than any other, saved Britain - booted out.
Guess who got his job? Leigh-Mallory, who had been obstructive to Park, often refusing to send up his own 11 Group fighters when requested by Park, and insisting on adopting the "Big Wing" concept, which took so long to assemble that often the German planes had dropped their bombs and were well on their way home. And Park himself was shuffled off to some administrative post.
In the movie Battle of Britain, these political fights were well represented. Sir Laurence Olivier, who played Dowding so well, had spent countless hours studying film and sound recordings of the man he was about to portray, and those who had known Dowding said that his portrayal was eerily accurate.
Eleven
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Leigh-Mallory is not viewed by history or his contemporaries with much enthusiasm. It is amazing that despite that, he rose to high levels. That sort of political stuff is world wide. I listened to one British Battle of Britain vet a couple years ago on TV who remarked that they thought they were up against the best airforce in the world only to find out after the war they were fighting The Three Stooges!! Don't recall who that fellow was.
Nickodell
Donation Time
Well, I think the years must have dimmed his memory. The Three Stooges Air Force came very close to winning, and only Hitler's insistence on the Luftwaffe bombing London, (in retaliation for an RAF raid on Berlin, which itself was in retaliation for an accidental raid on London by the crew of a lost Heinkel 111), instead of continuing their successful attacks on RAF stations, gave the RAF a brief, but significant, breathing space.
The 3 Stooges/Luftwaffe entered WWII with combat experience in the Spanish Civil War, during which they developed tactics that at first cost the RAF many planes and lives. While the Bf-109 pilots flew in what later was called the "Finger Four" formation, using two pairs of fighters, with one always guarding the other's tail, the RAF carried on the pre-war air display-type close formation, where each pilot was concerned with flying really close formation behind the leader, their wingtips almost touching, with nobody able to look out behind for the Hun in the Sun.
Luckily, several inspired and independent-minded squadron and flight commanders said "bugger this," and adopted the same formation as the Germans. Their lossed dropped, and their victories went up. (This was well covered in the BBC series "Piece of Cake," available on DVD).
Also, while Britain entered the war with aviation gasoline of around 87-octane “Regular,” Germany already had 100-octane. By 1942, the Germans had raised this to 150. Rolls had tested the Merlin with 100-octane gasoline, and found it would happily motor on with manifold pressure raised from 43 to 48 in. Hg (inches of mercury), boosting it by 135 hp, but this was of academic interest as there was no 100-octane in the RAF’s storage tanks.
Fortunately, the Esso tanker Beaconhill arrived from the United States just before the Battle of Britain, bringing enough of the new fuel to serve the Hurricanes and Spitfires throughout the conflict. With higher permissible boost pressures, the additional speed and rate of climb were decisive. Without it, what was, in the words of the Duke of Wellington (referring to the earlier battle of Waterloo) “a damned close-run thing,” might well have turned the other way.
As the war progressed, first 130, and finally 150-octane gasolines were produced in the United States and delivered, at great risk and loss of life, across the U-Boat infested Atlantic, enabling Rolls-Royce to squeeze the maximum possible power and range from the engine, at great advantage in the Spitfire, Hurricane II, Mosquito, Lancaster and P-51. Late-model Spitfires needed the 150-grade fuel when pursuing the V1 “flying bomb,” the world’s first cruise missile. Pilots called the Spits “clipped, cropped and clapped” – the wingtips were removed and the supercharger impeller diameter reduced, for improved low-altitude performance, and the brutally over-stressed engines quickly became “clapped out.” (The last 3 paragraphs are exerpted from my upcoming article The Magnificent Merlin [Advt.])
The 3 Stooges/Luftwaffe entered WWII with combat experience in the Spanish Civil War, during which they developed tactics that at first cost the RAF many planes and lives. While the Bf-109 pilots flew in what later was called the "Finger Four" formation, using two pairs of fighters, with one always guarding the other's tail, the RAF carried on the pre-war air display-type close formation, where each pilot was concerned with flying really close formation behind the leader, their wingtips almost touching, with nobody able to look out behind for the Hun in the Sun.
Luckily, several inspired and independent-minded squadron and flight commanders said "bugger this," and adopted the same formation as the Germans. Their lossed dropped, and their victories went up. (This was well covered in the BBC series "Piece of Cake," available on DVD).
Also, while Britain entered the war with aviation gasoline of around 87-octane “Regular,” Germany already had 100-octane. By 1942, the Germans had raised this to 150. Rolls had tested the Merlin with 100-octane gasoline, and found it would happily motor on with manifold pressure raised from 43 to 48 in. Hg (inches of mercury), boosting it by 135 hp, but this was of academic interest as there was no 100-octane in the RAF’s storage tanks.
Fortunately, the Esso tanker Beaconhill arrived from the United States just before the Battle of Britain, bringing enough of the new fuel to serve the Hurricanes and Spitfires throughout the conflict. With higher permissible boost pressures, the additional speed and rate of climb were decisive. Without it, what was, in the words of the Duke of Wellington (referring to the earlier battle of Waterloo) “a damned close-run thing,” might well have turned the other way.
As the war progressed, first 130, and finally 150-octane gasolines were produced in the United States and delivered, at great risk and loss of life, across the U-Boat infested Atlantic, enabling Rolls-Royce to squeeze the maximum possible power and range from the engine, at great advantage in the Spitfire, Hurricane II, Mosquito, Lancaster and P-51. Late-model Spitfires needed the 150-grade fuel when pursuing the V1 “flying bomb,” the world’s first cruise missile. Pilots called the Spits “clipped, cropped and clapped” – the wingtips were removed and the supercharger impeller diameter reduced, for improved low-altitude performance, and the brutally over-stressed engines quickly became “clapped out.” (The last 3 paragraphs are exerpted from my upcoming article The Magnificent Merlin [Advt.])
mikephillips
Donation Time
Nick,
I'm just saying that the circumstances that lead to the development of the P-51 might not have existed if the P-40 the British initialled expressed interest in was more in line with what the P-51 ended up as. Would North American at that time offered to come up with something better if the P-40 was that much faster?? Remember that the Army wasn't particularly interested in the project at that time due to politics, not being at war and so on. If the British hadn't pushed their need and North American wasn't so sure they could do better, pushing development of a new fighter off untl say 42 when we were completely involved in the war, who knows what might have happened. And it would have been competing for dollars then with the P-47 and P-38 programs which would have been further alone. And consider too how many programs for non carrier based aviation seemed to never generate actual production aircraft during that time.
I'm just saying that the circumstances that lead to the development of the P-51 might not have existed if the P-40 the British initialled expressed interest in was more in line with what the P-51 ended up as. Would North American at that time offered to come up with something better if the P-40 was that much faster?? Remember that the Army wasn't particularly interested in the project at that time due to politics, not being at war and so on. If the British hadn't pushed their need and North American wasn't so sure they could do better, pushing development of a new fighter off untl say 42 when we were completely involved in the war, who knows what might have happened. And it would have been competing for dollars then with the P-47 and P-38 programs which would have been further alone. And consider too how many programs for non carrier based aviation seemed to never generate actual production aircraft during that time.
Nickodell
Donation Time
I agree. You have agood point, Mike. A Super P-40 might have been ordered in the hundreds by the Brits., the P-51 never seeing the light of day. The consequences?
Carrying 270 gallons of fuel internally, and two 75-gallon drop-tanks, with the high fuel economy of the Merlin, the Mustang had an endurance of seven and a half hours. It could escort the B-17s and B-24s to any target in Germany, and outfight any Luftwaffe plane on the way there and back. But, although bomber losses dropped dramatically, General James H. “Jimmy” Doolittle held that the US Eighth Air Force was committing the same mistake Herman Goering did in the Battle of Britain – compelling the escorts to stay in close formation with the bombers instead of free ranging around and ahead.
On assuming command of the Eighth on January 6, 1944, he noticed a sign at VIII Fighter Command headquarters: THE FIRST DUTY OF THE EIGHTH AIR FORCE FIGHTERS IS TO BRING THE BOMBERS BACK ALIVE. Doolittle ordered it changed to: THE FIRST DUTY OF THE EIGHTH AIR FORCE FIGHTERS IS TO DESTROY GERMAN FIGHTERS. The bombers would be bait to trap the Luftwaff, the objective being the total destruction of its fighter arm and the achievement of allied air superiority over Europe, in preparation for D-Day (in fact almost no German aircraft attacked the invasion beaches) and to enable US and British aircraft to bomb key targets at will, by day.
Soon, whole fighter groups were allowed to freelance, and the Luftwaffe hunters became the hunted. Communication experts in England monitored German radio transmissions and vectored the Mustangs in to attack enemy fighters as their formations assembled; free-ranging Mustangs destroyed German fighters on the ground, or during takeoff and landing, including Me-262 jets. In February and March the Luftwaffe lost 4,236 aircraft. Although German fighter production rose from 24,807 in 1943 to 44,000 in 1944,2 lack of fuel and relentless pressure by the allied air forces overwhelmed the Luftwaffe. Pilots were being killed faster than they could be replaced, and by the time of the last major raid on April 25, 1945, the once all-conquering force had virtually ceased to exist.
Without the P-51 Mustang, air superiority could not have been won in 1944. The invasion of Europe might have failed as a dominant Luftwaffe pounded invasion craft and beaches. The war could have dragged on into 1946, the Allies facing several thousand piston-engined and jet fighters, and Arado Ar-234s (the world’s first jet bomber) attacking them in the air, bombing and strafing them in the invasions ports and all across France, Italy, Germany and Eastern Europe, assaulting their vulnerable supply lines and protecting German armies, armament factories and oil refineries.
Instead, Albert Speer, Hitler’s armaments minister, told the Japanese ambassador: "For the first time … raids, which might deal a really fatal blow to Germany, have begun."
Carrying 270 gallons of fuel internally, and two 75-gallon drop-tanks, with the high fuel economy of the Merlin, the Mustang had an endurance of seven and a half hours. It could escort the B-17s and B-24s to any target in Germany, and outfight any Luftwaffe plane on the way there and back. But, although bomber losses dropped dramatically, General James H. “Jimmy” Doolittle held that the US Eighth Air Force was committing the same mistake Herman Goering did in the Battle of Britain – compelling the escorts to stay in close formation with the bombers instead of free ranging around and ahead.
On assuming command of the Eighth on January 6, 1944, he noticed a sign at VIII Fighter Command headquarters: THE FIRST DUTY OF THE EIGHTH AIR FORCE FIGHTERS IS TO BRING THE BOMBERS BACK ALIVE. Doolittle ordered it changed to: THE FIRST DUTY OF THE EIGHTH AIR FORCE FIGHTERS IS TO DESTROY GERMAN FIGHTERS. The bombers would be bait to trap the Luftwaff, the objective being the total destruction of its fighter arm and the achievement of allied air superiority over Europe, in preparation for D-Day (in fact almost no German aircraft attacked the invasion beaches) and to enable US and British aircraft to bomb key targets at will, by day.
Soon, whole fighter groups were allowed to freelance, and the Luftwaffe hunters became the hunted. Communication experts in England monitored German radio transmissions and vectored the Mustangs in to attack enemy fighters as their formations assembled; free-ranging Mustangs destroyed German fighters on the ground, or during takeoff and landing, including Me-262 jets. In February and March the Luftwaffe lost 4,236 aircraft. Although German fighter production rose from 24,807 in 1943 to 44,000 in 1944,2 lack of fuel and relentless pressure by the allied air forces overwhelmed the Luftwaffe. Pilots were being killed faster than they could be replaced, and by the time of the last major raid on April 25, 1945, the once all-conquering force had virtually ceased to exist.
Without the P-51 Mustang, air superiority could not have been won in 1944. The invasion of Europe might have failed as a dominant Luftwaffe pounded invasion craft and beaches. The war could have dragged on into 1946, the Allies facing several thousand piston-engined and jet fighters, and Arado Ar-234s (the world’s first jet bomber) attacking them in the air, bombing and strafing them in the invasions ports and all across France, Italy, Germany and Eastern Europe, assaulting their vulnerable supply lines and protecting German armies, armament factories and oil refineries.
Instead, Albert Speer, Hitler’s armaments minister, told the Japanese ambassador: "For the first time … raids, which might deal a really fatal blow to Germany, have begun."
skywords
Donation Time
Curtis did try to upgrade the P-40 with variants like the XP-53 to the XP-60A my favorite being the straight XP-60 with the merlin. The concerns over the availabilty of the merlin forced it to be re engined with the Continental inverted vee that proved to be less than promised.
The XP-60
The XP-60
Rick, right on about the availability of the Merlin.
When Nick speaks of powering everything with wings with a Merlin, he seems to forget all the Merlins were spoken for and GM had the capability to produce thousands of Allisons. It would have been stupid not to use the Allision wherever it "worked". The P38 "worked" in the Pacific. Producing large engines in sufficient quantities was a problem the US manufacturing juggernault never cracked.
Bill
When Nick speaks of powering everything with wings with a Merlin, he seems to forget all the Merlins were spoken for and GM had the capability to produce thousands of Allisons. It would have been stupid not to use the Allision wherever it "worked". The P38 "worked" in the Pacific. Producing large engines in sufficient quantities was a problem the US manufacturing juggernault never cracked.
Bill
mikephillips
Donation Time
Certainly there were limits to the P-40 design that limited it's upgrade potential. But if a better version of the Allison was available in the late 30s making the prewar version more comparible with it's European contemporaries, particularly at altitude, then North America might not have seen developing a newer design as worthwhile since that probably would have required much more than the 60 days to fly promise. So on soldiers the P-40, which might have been redesigned around the Merlin and produced then since 1000s of those engines would not have been going to P-51 production.
Nickodell
Donation Time
Merlins were hardly scarce, with over 160,000 produced in WWII - 60,000 by Packard and 100,000 in England between Rolls-Royce and British Ford. Total production of aircraft using it in WWII was around 60,000, or not much more than one third of total production. Even allowing for replacements, losses and refurbishing, there were still plenty to spare. And if Packard could produce them, so could have GM, Chrysler and US Ford.
Politics was the overriding reason so many US planes were lumbered with the Allison, right up to the Korean War. This has been well documented by such top aviation historians as Walter J. Boyne (see, for example, his Clash of Wings), Heschel Smith (A History of Aircraft Piston Engines) and Graham White (Allied Piston Aircraft Engines of WWII.) Politics even prevented the P-39 Airacobra from becoming a great fighter, as Bell was denied the use of the turbocharger, and again it suffered from poor altitude performance.
Incidentally, the Merlin was the only non-US engine used by the US in a US-built aircraft.
True, the P-38s did great service in the pacific, where long range and the assurance of two engines were important, but the turbocharged Allison, which did OK in mild climates, suffered severe technical problems in Europe, such as oil congealing or foaming, bearing and connecting rod failure. By October 1944 the Eighth Air Force gave up on them, replacing them with P-47s and P-51s.
The P-40 was based on an older aircraft, the P-36. The forward section and engine were new, but from the firewall to tail it was exactly the same as the P-36. (In this it was similar to the Hurricane, which was a development of the earlier Hawker Hart biplane). Because of this, the P-40, like the Hurricane, is thought to have been in some ways obsolescent from its inception. However, at lower levels (up to about 15,000 feet) it was as fast as the Spitfire I and Messerschmitt Bf-109E, although both could outclimb it, and it was better armed. Hence it did so well with the AVG in China, and in the Western Desert with the RAF – in fact, some Luftwaffe pilots said they feared it more than the Hurricane at lower altitudes. As with the Allison P-51, however it ran out of breath at higher altitudes where much of the air war was fought from 1943 onwards.
Politics was the overriding reason so many US planes were lumbered with the Allison, right up to the Korean War. This has been well documented by such top aviation historians as Walter J. Boyne (see, for example, his Clash of Wings), Heschel Smith (A History of Aircraft Piston Engines) and Graham White (Allied Piston Aircraft Engines of WWII.) Politics even prevented the P-39 Airacobra from becoming a great fighter, as Bell was denied the use of the turbocharger, and again it suffered from poor altitude performance.
Incidentally, the Merlin was the only non-US engine used by the US in a US-built aircraft.
True, the P-38s did great service in the pacific, where long range and the assurance of two engines were important, but the turbocharged Allison, which did OK in mild climates, suffered severe technical problems in Europe, such as oil congealing or foaming, bearing and connecting rod failure. By October 1944 the Eighth Air Force gave up on them, replacing them with P-47s and P-51s.
The P-40 was based on an older aircraft, the P-36. The forward section and engine were new, but from the firewall to tail it was exactly the same as the P-36. (In this it was similar to the Hurricane, which was a development of the earlier Hawker Hart biplane). Because of this, the P-40, like the Hurricane, is thought to have been in some ways obsolescent from its inception. However, at lower levels (up to about 15,000 feet) it was as fast as the Spitfire I and Messerschmitt Bf-109E, although both could outclimb it, and it was better armed. Hence it did so well with the AVG in China, and in the Western Desert with the RAF – in fact, some Luftwaffe pilots said they feared it more than the Hurricane at lower altitudes. As with the Allison P-51, however it ran out of breath at higher altitudes where much of the air war was fought from 1943 onwards.