P-40 vs. Yak-1 vs. Hurricane

[Schweik]

"bitching'" (complaining)

You are trying to nit pick, Curtiss was making Allison engines under the direction of Allison, or are you suggesting it was some new Curtiss engine? Did Curtiss set up the factory on their own? Did they create the tools and jigs?

I am not sure why you are dragging Curtiss Wright into the discussion as to what Allison did or didn't do to develop their engine better. Any evidence that Allison was guilty of what Wright was?

Again, it's pretty simple - we both know those were Allison engines being made in that factory.

S

 

[Schweik]

Edit: nevermind!

 

[Shortround6]

You are trying to nit pick, Curtiss was making Allison engines under the direction of Allison, or are you suggesting it was some new Curtiss engine? Did Curtiss set up the factory on their own? Did they create the tools and jigs?



Again, it's pretty simple - we both know those were Allison engines being made in that factory.

S

The Wright factory in Ohio was Making R-2600 air cooled radial engines. Not Allison V-1710s

Wright was 100% responsible for the The Plant in Ohio as Wright was reluctant to licence it engines to other companies.

Wright and Allison had nothing to do with each other.

I have no knowledge of Wright ever building an Allison piston engine during during WW II.

 

[Schweik]

You are right, I owe you an apology. I had read about this several times and always assumed it was Allison engines. I stand corrected.

Found this link explaining details of the investigation of the scandal for anyone interested.

 

[Shortround6]

And what type of engine is the V-1710? Are you suggesting Allison wasn't part of that? I should have guessed this was the angle certain people would take, but I don't think Allison can wash their hands of their own engines being built in another companies factory - as far as I know nearly every major aircraft or aircraft engine company had manufacturing done in other companies factories, right?

Allison had all it's subcontracting done in in General motors plants but Allison was the ONLY assembly plant for the V=1710 engine.
Unless you can show proof otherwise.

They solved the survivability problem for P-40s by increasing (low altitude) horsepower from 1150 to ~1550 and that is pretty good for what has been implied were retarded teenagers who barely knew how to count. Saved a lot of lives and basically made the aircraft viable again which was needed due to the failure of so many other designs like the P-39, P-35*, P-43*, P-46, P-60, and the (at that time still struggling) P-38.* before somebody nit-picks this I am well aware that these designs paved the way for the excellent P-47 but it took quite a while to get there and the war was still on.

Italic: I never implied that, that is you interpretation. Stop putting words in peoples mouths.
You do know that the P-35 predated even the P-36 was out of production and never going to be reinstated by the time the first P-40s came off the line.?

The institutions, corporate and government, did enough of their part to get the country in position to survive, but it's also hyperbole to ignore the innovations in the field. It was from the field that the idea of putting bombs on several of the available fighters originated, when the bombers on hand were inadequate to do the job (and putting fighter escorts at risk because they were so slow). It was in the field that successful efforts were taken to lighten fighters (which were later copied by Curtiss), where the new boost settings got established which were later accepted by Allison, and so on. It was in the field that skip bombing was invented. Or the defensive gun added to the Il-2. The adoption of the finger-four and flying in pairs. And so on.

Bombs under a fighter, what a novel idea, why didn't somebody think of that before?????

P-26 Peashooter bomb rack.

Bombs under fighters goes back to WW I. One reason the P-40 was so easy to hang bombs under was that Curtiss had offered export Hawk 75s with not only the under fuselage bomb rack (up to 500lbs) but a light bomb rack in each wing.

see. http://www.wwiiaircraftperformance.org/P-36/Curtiss_Hawk_75-A_Detail_Specifications.pdf
The P-35 was rated at a 350lb bomb load.
why the bomb load went away on the early P-40s is an unexplained mystery but sorry, men in the field did NOT invent the concept.

 

[Schweik]

Ok, are you seriously denying that they didn't implement new and more bomb racks on multiple different aircraft in the field? I never said it hadn't ever been done before.

Pre-war bomb loads - especially for fighters- were usually insufficient for real combat needs.

In order to be effective, more effective than the available light or medium bombers on hand, they had to get them to carry quite heavy bomb loads which they did largely as a matter of improvisation, on more than one aircraft and in more than one Theater. They also added other weapons like rockets a bit later on.

 

[Schweik]

Allison had all it's subcontracting done in in General motors plants but Allison was the ONLY assembly plant for the V=1710 engine.
Unless you can show proof otherwise.

I already conceded this point.

 

[CORSNING]

Great pictures SR6. Thank you for sharing.

 

[Schweik]

The thing with the bomb racks is actually very similar to the issue with overboosting. There was some capacity there for some planes (oddly not the original P-40) but it was inadequate to actual needs. Somebody in the field had to figure out how to put heavier and larger bombs on the planes, how to put in more and stronger bomb shackles and so on, and then somebody had to test the plane, see if it could take off and then later work out the safe margins for (shallow) dive bombing etc.

 

[Reluctant Poster]

RR sort of stumbled into hiring Stanley Hooker and in fact didn't really know what they wanted him to do when they hired him.

Rolls Royce didn't luck into Stanley Hooker, they were more interested in basic research than any other engine company at the time and hired him specifically to look at things without preconceived notions. They also hired AA Griffith at about the same time to do research on axial flow gas turbines. Rolls Royce was a very technically advanced company that did a lot of basic research leading to things such a ram intakes, ejector exhaust and extended surface radiators. They also experimented with turbo charging, diesels, sleeve valves, air cooling, steam cooling and two strokes.
In any event Hooker takes way too much credit for the success of the Merlin. Yes he designed an excellent supercharger (building on the work of Ellor) but without the well designed induction system the effect would have been lost. Hooker was responsible for an accessory for Merlin not the engine itself, which was the responsibly of Cyril Lovesey. Lovesey was a much more modest man than Hooker so he never got the credit he deserved. The difference between Hooker and Lovesey's personalities is perfectly illustrated by the following clip. Start watching at the 4.00 minute mark. Poor Lovesey can't get a word in edge wise.

 

[Shortround6]

I think both points of view may be correct.

RR certainly seemed interested in hiring academics to further research. On the other hand when first hired Hooker wasn't assigned any duties and was told to look around and see what interested him (according to his autobiography). Had some other aspect of the Merlin (or other engines being worked on ) struck his fancy first would RR supercharger development moved along as it did?

Hooker certainly had little to do with the main part of the Merlin engine and anything that had to do with the Merlin being able to stand up to the power the superchargers could provide.

On the other hand many companies could build a good, sturdy engine that performed well at low altitude (some couldn't-Armstrong Siddeley Tiger) but that is not what set the Merlin apart. From the Merlin XX on it was the Merlin's ability to operate at high altitudes that was it's main claim to fame.

The supercharger may have been an "accessory" in the mid to late 1930s but by mid-way through the war the supercharger design had come to dominate (or at least strongly influence)
aircraft design. Once you get to two stage superchargers (turbo or mechanical) and their antendent intercooler system/s the weight and volume of the supercharger installation becomes more than a mere accessory.

 

[Dan Fahey]

It's hardly a big secret, and google is your friend.

Curtiss-Wright - Wikipedia

They were installing defective engines and then bribing Army inspectors to slip them through to the combat units. I would call this criminal negligence. It was a plague for the US, every country had it's own particular kind of cultural problems in meeting the challenges of aircraft production in WW2, but for the US it was corporate corruption.

from the wiki:

"From 1941 to 1943, the Curtiss Aeronautical plant in Lockland, Ohio produced aircraft engines under wartime contract destined for installation in U.S. Army Air Forces aircraft.[8][9] Wright officials at Lockland insisted on high engine production levels, resulting in a significant percentage of engines that did not meet Army Air Forces (AAF) inspection standards. These defective engines were nevertheless approved by inspectors for shipment and installation in U.S. military aircraft. After investigation, it was later revealed that Wright company officials at Lockland had conspired with civilian technical advisers and Army inspection officers to approve substandard or defective aircraft engines for military use.[8][9] Army Air Forces technical adviser Charles W. Bond was dismissed by the Army in 1943 for "gross irregularities in inspection procedure."[10] Bond would later testify that he had been "wined and dined" by Wright company officials; one of those occasions was the night before Bond fired four AAF engine inspectors another AAF inspector had described as "troublemakers."[10] In 1944, three Army officers, Lt. Col. Frank Constantine Greulich of Detroit, former chief inspection officer for the material command, Major Walter A. Ryan of Detroit, former central states inspection officer, and Major William Bruckmann, a former Cincinnati brewer and resident Army inspections officer at the Wright plant in Lockland were charged with neglect of duty, conspiracy, and giving false testimony in a general court martial.[11][12][13] All three men were later convicted of neglect of duty.[13] The story of defective engines had reached investigators working for Sen. Harry Truman's congressional investigative board, the Truman Commission, after several Wright aircraft assembly workers informed on the company; they would later testify under oath before Congress.[8][9][14] Arthur Miller's play All My Sons is based on this incident.[15]"



I'd like to point out, I'm not "bitching and moaning", I was referring to historical facts. I appreciate that it's useful to approach history from a variety of perspectives and have no problem, in fact appreciate your well informed perspective from the manufacturers point of view. But please don't get carried away. I'm not a bitch and don't appreciate being referred to as one implicitly or otherwise.



I don't think there were many aircraft or engine manufacturers that didn't have to suddenly ramp up production from the tiny level of aircraft needed for civilian use in the 30's to the massive numbers demanded by the military forces in the 1940's. No doubt it was an immense challenge, but so was fighting for survival against a determined and well trained enemy in high performing fighters, in a not quite perfected aircraft that you only had 20 hours of flight time in. So was surviving El Alamein or the invasion of Guam or the Bataan Death March. World War II was an unprescedented screaming emergency that snuffed out the lives of 40-60+ million people depending on how you did the math. Everyone had a hard time.

And yet the war lasted four years for the US, and Curtiss and Allison certainly saw it coming. They had time to make certain decisions (as other aircraft and engine manufactuers did) and they didn't. In fact they cut corners, instigated corruption and got caught doing it. Cutiss also failed to make almost any useful major designs after the P-40 (one transport plane and one float plane, the rest basically all failed), which is why Curtiss aircraft folded shortly after WW2.

The P-40 was a good fighter, and the Allison was a good engine, there were many good people and obviously some excellent engineers involved in their production, but there were also clearly issues with the management of both Curtiss and Allison or it's parent company or both which prevented it from becoming a great engine - and that cost many lives. The rest is just excuses.



I'm not sure what mythological context you are coming from, but don't be confused, I never said that mechanics in the field knew more about engine design than Allison or Rolls Royce did, I'm saying they successfully rose to the challenge of getting the problems solved before the manufacturer did, certainly in the case of Allison. That again is an historical fact.

S

Adding to this conversation ! Tossing this out here.

Initially the British had the better Fighters and Engines.
Ironically I think the Allison was a better engine than the Watch Maker Merlin.
Just the British developed what they had into a great performer.

British had to survive creating urgency and different decisions.
The US was a 2 years late bit player in WW2 compared to all the other Combatants.
Think we horribly lost about 500000 soldiers in WW2.
Britain about three times that, Russians and Chinese each ten times that.

US did contribute a lot but never seemed to be as urgent.
Such as neglecting our own jet engine and rocket technology.
The Atom Bomb did take precedence.

The US continent was not attacked had did not have to defend a large land battle.
IMHO the Navy seemed to have a different attitude than the Army.

Never understood the number of failed Curtis designs.
Yet the P40 Q model would have been a vast improvement and could be fielded by 1943

I am of the mind that it was the British that gave NAA the plans for the P51 to build.
NAA made their design changes for manufacturing.
Yet our Military had nothing close to this plane.
Because of NIH it had a moderate start.
Once US desperation set in it got integrated as a world class fighter.

Then there is the US Sherman tank not upgrading to a better Cannon...!
Despite the British installing theirs and able to give the US them.

I guess hindsight is 20/20
Hope I did not steal this post.

Dan

 

[CORSNING]

Adding to this conversation ! Tossing this out here.
Yet the P40 Q model would have been a vast improvement and could be fielded by 1943
Wow! GregP is going to love you.

I guess hindsight is 20/20
If the correct spectacles are used.

Hope I did not steal this post.
Now that is an act that I would consider impossible considering the firepower of this
group.

Dan

Jeff

 

[Elvis]

Initially the British had the better Fighters and Engines.
Ironically I think the Allison was a better engine than the Watch Maker Merlin.
Just the British developed what they had into a great performer.

Dan

I've said it before, 200-300 lb. weight difference between the Allison and the Merlin means the British one was a heavier built engine.
You can put more stress (i.e., power) on either engine but the Merlin will stand up to it better.
Hydroplane crews in the 50's-70's found the same thing.

Elvis

 

[wuzak]

I've said it before, 200-300 lb. weight difference between the Allison and the Merlin means the British one was a heavier built engine.
You can put more stress (i.e., power) on either engine but the Merlin will stand up to it better.
Hydroplane crews in the 50's-70's found the same thing.

Elvis

That extra 300lbs includes a 2nd stage supercharger, an intercooler and 2 speed supercharger drive.

Equivalent single stage Merlins were 25-50lbs heavier than the V-1710.

And the 2 speed, single stage, Merlin XX series was only about 100lbs heavier.

 

[Shortround6]

Ironically I think the Allison was a better engine than the Watch Maker Merlin.

Isn't it time we relegated this myth to the rubbish bin?
No less than Stanley Hooker relates a story about when the guys from Ford of England showed up to look things over when they were setting up a shadow factory.
After a number of days (or a few weeks) one the head Ford guys comes to the office that S. Hooker was sharing and complains to the other guy in the office that Ford can't make the engines using the drawings and tolerances that RR is using. S. Hooker pipes up and says something like they can't hold the tolerances that RR uses. The Ford guy answers and says no, the tolerances are too loose. You can't mass produce low price cars (or thousands of aircraft engines) unless the parts are completely interchangeable.
A more accurate account is in Stanley Hookers autobiography.
Now the Merlin may have been a pain in the butt to work on because RR never used 2 screws to hold a cover on when they could use 6-8 screws but the Merlin wasn't built to a finer tolerances than any other high powered aircraft engine of the time.

 

[Elvis]

That extra 300lbs includes a 2nd stage supercharger, an intercooler and 2 speed supercharger drive.

Equivalent single stage Merlins were 25-50lbs heavier than the V-1710.

And the 2 speed, single stage, Merlin XX series was only about 100lbs heavier.

...ok, I stand corrected...

From the 456th Fighter Squadron website...

"The production Allison turned out to be the sturdy and reliable powerplant that its designers had striven for. The only thing that stood between the Allison and real greatness was its inability to deliver its power at sufficiently high altitudes. This was not the fault of its builders. It resulted from an early Army decision to rely on turbo supercharging to obtain adequate power at combat heights. Even this decision was not a technical error. A turbo supercharged Allison was as good a high-altitude engine as most. The trouble was that the wartime shortage of alloying materials, especially tungsten, made it impossible to make turbo superchargers for any but a small proportion of Allisons.
Bomber engines got the priority.
The few turbo-supercharged Allisons that were made were allocated to P-38s, making the high-altitude performance of that plane its best feature.
All 14,000 P-40s got gear-driven superchargers and, as a result, were never first-class fighter planes. Donaldson R. Berlin, the P-40 designer, has said that P-40s experimentally equipped with turbo-superchargers outperformed Spitfires and Messerschmitts and that if it had been given the engine it was designed for, the P-40 would have been the greatest fighter of its era.
This may be to some extent the bias of a proud parent, but there is no doubt that the deletion of the turbo supercharger ruined the P-39.
Had Allison's engineers been able to put the effort into gear-driven superchargers that Pratt and Whitney and Rolls-Royce did, it might have been a different story. As it was, there can be little doubt that the V-1710 had more potential than was actually exploited."

Would be interesting to see a turbocharged P-40 go up against a Bf-109.



Elvis

 

[wuzak]

That is, in my opinion a myth.

The P-40 was never meant to have a turbocharger, though one was proposed, based on the E, but never built.

Some history:
The first Model 75 Hawk prototype was converted to use a turbocharged V-1710 and was designated the XP-37.

This featured the original style turbocharger, which had the compressor reversed so that it drew air in over the centre bearing. The turbocharger proved unreliable.

The installation of the radiator and intercooler behind the engine meant that the cockpit had to be moved aft, so that it was just forward of the fin.

The USAAC was impressed enough to order service test versions as the YP-37.

This featured a revised turbo, which was the first of the B-series turbos used through WW2. The turbo remained unreliable.

The YP-37 differed by having a longer rear fuselage, which solved some of the issues with stability that the XP-37 had.

Due to the reliability issues with the turbocharger, Berlin and Curtiss requested an altitude rated V-1710 to fit into the P-36 airframe. The 10th production P-36 was converted to the V-1710 and was designated XP-40.

The XP-40 flew about a year after the XP-37 and a year before the YP-37.

A later development was the XP-53, which was based on the P-40 fuselage, but with the Continental IV-1430 engine and laminar flow wings. Because of the delay in getting flight approved IV-1430s, the decision was made to fit the V-1650-1, which was starting licence production at Packard, instead. The aircraft was redesignated XP-60.

Several other P-60 variants were devised:
XP-60 with V-1650-1 Merlin, started as XP-53
XP-60A with V-1710 and GE turbo
YP-60A with V-1710 and GE turbo, completed as YP-60E
XP-60B with V-1710 and Wright turbo, completed as XP-60E
XP-60C with R-2800 and contra-rotating propellers (was originally supposed to get the Chrysler IV-2220)
XP-60D with V-1650-3 2 stage Merlin - converted from XP-60
XP-60E with R2800 and single rotation propeller
YP-60E with R2800 and single rotation propeller

The XP-60, XP-60A, XP-60C, XP-60D, XP-60E and YP-60E all flew.

The XP-60's first flight was in September 1941.

The XP-60A had an engine fire during taxiing tests in late 1942, so modifications were made prior to the first flight.

The XP-60A was the closest to a turbocharged P-40, though it used a different fuselage to the XP-60/XP-60D, which was based on the P-40.

And by the time it flew, Berlin was gone from Curtiss.

 

[Shortround6]

Unfortunately the whole Curtiss P-36 through P-60 story is a convoluted mess.
No P-40 ever flew with a turbo.
A P-36/Hawk 75 may have. there seems to be some confusion as to whether it flew with a two stage mechanical or a turbo or with both at different times. The Company demonstrator was rebuilt a number of times.
You have the XP-37 and YP-37s as already mentioned.
You have the XP-60A which was fitted with a turbo but caught fire during ground running and the turbo was removed when the plane was repaired and most (or all) of the flights were done without the turbo.

There are no published photos of a P-40 with a turbo, there are no published drawings of a P-40 with a turbo. There are references to a turbo being shipped to the Curtiss factory but no evidence of metal actual being cut for a P-40. I have no Idea if that turbo wound up in the XP-60A

 

[tomo pauk]

...ok, I stand corrected...

From the 456th Fighter Squadron website...

"The production Allison turned out to be the sturdy and reliable powerplant that its designers had striven for. The only thing that stood between the Allison and real greatness was its inability to deliver its power at sufficiently high altitudes. This was not the fault of its builders. It resulted from an early Army decision to rely on turbo supercharging to obtain adequate power at combat heights. Even this decision was not a technical error. A turbo supercharged Allison was as good a high-altitude engine as most. The trouble was that the wartime shortage of alloying materials, especially tungsten, made it impossible to make turbo superchargers for any but a small proportion of Allisons.
Bomber engines got the priority.
The few turbo-supercharged Allisons that were made were allocated to P-38s, making the high-altitude performance of that plane its best feature.

Last 3-4 sentences are myths abound.
USA was not short of war materials, tungsten included. About 20000 (20 thousand) of V-1710s + spares that were installed on P-38s were turbocharged. 20000 turbocharged engines is probably more engines than what Japan produced in 1940+1941+1942, including engines for trainers and transports.
USA also installed more than 15600 tubochargers on P-47s, of the type that was bigger, heavier and more expensive than turbos used on bombers or on P-38s.

All 14,000 P-40s got gear-driven superchargers and, as a result, were never first-class fighter planes. Donaldson R. Berlin, the P-40 designer, has said that P-40s experimentally equipped with turbo-superchargers outperformed Spitfires and Messerschmitts and that if it had been given the engine it was designed for, the P-40 would have been the greatest fighter of its era.
This may be to some extent the bias of a proud parent, but there is no doubt that the deletion of the turbo supercharger ruined the P-39.
Had Allison's engineers been able to put the effort into gear-driven superchargers that Pratt and Whitney and Rolls-Royce did, it might have been a different story. As it was, there can be little doubt that the V-1710 had more potential than was actually exploited."

1st sentence is moot - plenty of fighters were good/great even if their S/C was gear-driven. 2nd sentence has zero proof, ergo it's a myth. 3rd sentence - installation of turbo almost runied P-39 program, and, with it, Bell aircraft company.
Allison was a small company when compared with RR and P&W, so yes, their resources were too small to make, all in the same time, a V-1710 in several flavors (turbo or not, pusher or pull, with or without remote gearbox etc.).
Latest quoted sentence is probably true - with a good S/C and some nip & tuck, V-1710 was in the league of Merlin or DB 601/605.

BTW - nobody seems to blame USAAC/AAF for requiring from the P-39 and P-40 to carry about same weight of guns & ammo as it was the case with P-38 with much more altitude power.