Curtiss-Wright: Loss of Don Berlin and downfall

[Shortround6]

Anyway, none of this really applies to Curtiss given they didn't have a major stake in the carrier borne fighter arena.

True but the P-36 used a prop not much bigger than 10ft and had 8 3/4in clearance. A number of people have suggested a P-36 with the R-2600 while "waiting" for the R-2800 powered planes. Without wide cord blades it really wasn't going to be practical. The wide cord blades showed up. But by the time they did the R-2800 powered planes were in production.

As for Don Berlin and Curtiss: a few quotes form Joe Baughers web page on the XP-55.

"The Curtiss XP-55 Ascender was another response to Circular Proposal R-40C, which was issued on November 27, 1939. It called for a fighter that would be much more effective than any extant--with a top speed, rate of climb, maneuverability, armament, and pilot visibility, all of which would be far superior to those of any existing fighter."

"The Curtiss entry, designated CW-24 by the company, was perhaps the most unconventional of the four finalists. It was to be one of the last projects supervised by Donovan Berlin before he left the Curtiss company to go over to Fisher to work on the P-75.... Curtiss proposed to use the new and untried Pratt Whitney X-1800-A3G (H-2600) liquid-cooled engine, mounted behind the pilot's cockpit and driving a pusher propeller. Project maximum speed was no less than 507 mph"

"On June 22, 1940, the Curtiss-Wright company received an Army contract for preliminary engineering data and a powered wind tunnel model. The designation P-55 was reserved for the project."

Due to the army's doubts about the project the full scale flying model was built with low powered engine (275hp) and the project was delayed. Cancellation of the intended engine didn't help either. At any rate " On July 10, 1942, a USAAF contract was issued for three prototypes under the designation XP-55." and finally "It made its first test flight on July 19, 1943"

By this time Don Berlin had been gone from Curtiss for over a year.

Several things can be drawn from this time line. One was that Don Berlin's leaving from Curtiss had little to do with the down fall of the company. Another is that in 1939/1940 the Army wasn't interested in more "interim" fighters, it already had the P-39 and P-40 as interim fighters to tide them over until the P-38 and P-47 got going. They were interested in, and funding, a new generation of fighters. ALL of which fell fell on their asses, leaving them with improved P-38s, P-47s and the outsider the P-51.

 

[tyrodtom]

I guess I was wrong, I thought the XP-55 got called the Assender because of the engine in the rear, but maybe there was a little double meaning there, it fell on it's ass too.

I know it's official name was Ascender, but we know how people are.

 

[kool kitty89]

True but the P-36 used a prop not much bigger than 10ft and had 8 3/4in clearance. A number of people have suggested a P-36 with the R-2600 while "waiting" for the R-2800 powered planes. Without wide cord blades it really wasn't going to be practical. The wide cord blades showed up. But by the time they did the R-2800 powered planes were in production.

A dedicated R-2600 (probably with provisions to be adapted to the R-2800) powered fighter would have made more sense from a land-based fighter perspective too, but adapting the P-36 airframe has a ton of disadvantages. The V-1710 and R-1830 (particularly the 2-stage version) would seem the best potential new developments to go with in the 1939-1941 timeframe.

Developing a dedicated big-radial 1600-2000 HP class engine optimized airframe in leu of the initial XP-46 and XP-60 developments might have had more merit though. (the P-36/P-40 airframe already having fairly good drag characteristics and being well suited to the smaller engines while something totally new would much better match the characteristics of those larger engines -plus the ongoing cowling studies on the XP-42 could be fed into that work sooner than it eventually was on the delayed/troubled XP-60 program)

Several things can be drawn from this time line. One was that Don Berlin's leaving from Curtiss had little to do with the down fall of the company. Another is that in 1939/1940 the Army wasn't interested in more "interim" fighters, it already had the P-39 and P-40 as interim fighters to tide them over until the P-38 and P-47 got going. They were interested in, and funding, a new generation of fighters. ALL of which fell fell on their asses, leaving them with improved P-38s, P-47s and the outsider the P-51.

There was also Bell's XP-52 and XP-59 projects canceled in part to divert resources to the XP-59A jet project. That design seems like it might have been less troublesome than the likes of the XP-56 and XP-55 but certainly could have just ended up one more failure. The more conventional P-63 of course fell behind the P-51's development and failed to address any sorts of long-range requirements. (the XP-59 still seems interesting in that it might have actually converted well to the J33 later in development -size and pusher arrangement of the R-2800 would seem to fit well if the tailplane was repositioned, Vampire/Venom style, and perhaps made for interesting competition to the XP-80 project)

The number of projects upset more by pie in the sky engine developments (or lack thereof) certainly didn't help matters either. Hell, the number of designs held back by targeting the Army's pet XI-1430 is insane.

 

[gjs238]

Several things can be drawn from this time line. One was that Don Berlin's leaving from Curtiss had little to do with the down fall of the company. <SNIP>

Do you infer that Curtiss was doing very well before and after Don Berlin left and that his exit had no effect?
Or do you mean that Curtiss was already sliding downhill well prior to Don's exit?

 

[GregP]

Curtiss and Bell had the much same problems.

Most of the Curtiss designs were remarkably like the P-36 up to and including the XP-46 and even the XP-60 was similar but adapted to a radial. They never seemed to come up with something fresh.

Bell's designs were remarkably similar to one another. The Airacuda, Airacobra, King Cobra, and the XP-59A were all very similar airrames structurally and in terms of a lot of other characteristics.

When you have a family of planes, each of which is a bit disappointing in the level of performance versus the competition, it's time for a fresh approach, not a mild redesign. North american's approach was to say, "We can do better than a P-40 with the same engine." and they did. It was the XP-51.

The P-47 was evolutionary from the P-35, but with each evolution the performance increased. Ultimately the P-47N was one of the fastest planes of WWII.

The last P-40 was about as fast as the first one. The XP-40 averaged 315 mph in original form and after NACA wind tunnel tests, was cleaned up to make 366 mph. The P-40E made 360 mph with armament at best altitude. The P-40N went 378 mph at best altitude. It started out as a mediocre performer and stayed that way all through it's career.

The XP-47B made 412 mph at 25,800 feet. The P-47N made 460 mph at 30,000 feet. It started out a s a tough plane down low that could take punishment and a great performer up high. It stayed that way all through it's career.

 

[Shortround6]

Do you infer that Curtiss was doing very well before and after Don Berlin left and that his exit had no effect?
Or do you mean that Curtiss was already sliding downhill well prior to Don's exit?

It is hard to tell. Don Berlin was at the Buffalo plant for the Hawk 75/P-36/P-40/P-46. Not sure which plant built the XP-55. ST. Lewis was responsible for the C-46. He had nothing to do with the Helldiver as far as I know, perhaps he should have. You also had the Seamew which finally got replace with the Seahawk (577 built). He had nothing to do with either the engine division or the propeller division. Perhaps he could have come up with another winning design to pull Curtiss out of the dumps but Curtiss worked on more different programs by far than any other American aircraft company. Curtiss certainly tried hard to give the customers what they wanted. Perhaps they should have said no a bit more often.

Wiki says " Curtiss-Wright failed to make the transition to design and production of jet aircraft, despite several attempts. During the war, the company had expended only small amounts on aircraft research and development, instead concentrating on incremental improvements in conventional aircraft already in wartime production. This was especially true in the first two years of the war. Curtiss' failure to research and develop more advanced wing and airframe designs provided an opening for North American, Bell, Lockheed, Northrop, and other U.S. aircraft manufacturers to submit newer and more advanced aircraft designs"

Italics by me. However for Army fighters after the P-36/P-40 you had the XP-46, the XP-53, The XP-55, the XP-60 Series and the XP-62. The last using a turbo-charged R-3350 with contra rotating props and a pressure cabin.

Curtiss also tried two fighters for the Navy. the XF14C

and the mixed power XF15

Now perhaps is was Curtiss's lack of research into airfoils or structure that caused these projects to fail or perhaps it was changing requirements (neither the Japanese or the Germans were able field large numbers of high flying aircraft using pressure cabins). A number of Curtiss projects required modification or revision when the originally planed engines failed to make it to production.

Curtiss also built two different single engine/single seat attack aircraft for the Navy at the end of the war, the first in completion with the Skyraider.

This was NOT a Helldiver with a new engine and the rear gunner left out

the point is that Curtiss was NOT cruising along fat, dumb and happy making slightly improved P-40s and then wondering how the world passed them by. The P-40 might have represented 1/4 to 1/3 of the aircraft divisions revenue during WW II. While the failure to secure a successor to the P-40 was certainly important it might not have been fatal to the company if they had secured contracts for other types of aircraft.

 

[kool kitty89]

Curtiss and Bell had the much same problems.

Most of the Curtiss designs were remarkably like the P-36 up to and including the XP-46 and even the XP-60 was similar but adapted to a radial. They never seemed to come up with something fresh.

Bell's designs were remarkably similar to one another. The Airacuda, Airacobra, King Cobra, and the XP-59A were all very similar airrames structurally and in terms of a lot of other characteristics.

Bell had a good deal different problems, and the Aracuda had most of the same problems as the Kampfzerstorer concept. (had Bell aimed more at a heavy fighter/interceptor like an early predecessor to the P-38, it likely would have been a different story -hell, even aiming at mounting twin M4 cannons in the nose should have been more realistic than those manually-loaded pods ... 15 round link belts like the early P-38s used, I believe a more compact arrangement than the 30 round endless loop type belts used on the P-39)

Aerodynamically, the P-39 was rather sound, but slow improvements in the V-1710 (both slow approval for WEP and slow development of models with improved performance) hurt a good bit and the P-40 had similar problems. (imagine the Spitfire and Bf 109 if they'd ended up stuck with updated variations of the Merlin III and DB 601A in 1943 with basically the same superchargers and consistently lagging formal WEP ratings -the British consistently gave the Merlin WEP ratings vastly sooner than the USAAC/AAF did with the V-1710 or V-1650 ... or several radial engines) The 109 and Spitfire would also have both been in trouble with weight gains from USAAC minimal structural requirements.

Stick the Merlin XX in the P-40 at the same time as the Hurricane II gets it in Britain and throw in the +12 lbs boost rating and see how it compares in 1941. Throw in the 2-stage merlin at the same time the Spitfire IX gets it and see what happens. Do the same for the P-39. (or do the same for the P-51 and you'd have it in production with the Merlin 61 alongside the Spitfire IX ... or totally displacing the latter in production) -or have the USAAF pour funding into Allison for more aggressive engine development and testing for maximum power ratings, detonation limits on varying fuel grades, maximum allowable RPM, intake manifold efficiency, single stage supercharger performance, multi-stage supercharger performance, water injection, and intercooler designs.

The P-39 had issues with an overly sensitive CoG and difficult maintenance with some components, but those were the big issues. (armament could/should have been modified and range was already better than what the P-63A ended up with due to its intentionally REDUCED fuel capacity as an interceptor ... the P-63 might have given the P-51 more a run for its money had it been designed from the outside to be a long-range/escort fighter)

The P-59 ended up with a conservative design limited by its intended nature as a safe, foolproof engine testbed as well as lack of access to high-speed wind tunnels for testing. In the end it seems to have suffered from the same primary limitation as the Gloster Meteor: serious drag and overall aerodynamic problems related primarily with the engine nacelles. (low critical mach number, high transonic drag, directional snaking, and buffeting; the large, 14% thickness:chord wing wasn't the main source of the drag problems and certainly not the limiting mach factor: the wing should have fared similarly well to the Vampires and probably moderately worse than the Meteor's; unlike the Meteor, the P-59 never got redesigned, streamlined long-chord engine nacelles/ducting though they did get boundary layer bleed plates somewhat similar to the P-80 at the intake/fuselage interface -the large wing also shared the same issue of underutilization of internal space as the P-63, lots of volume with huge potential for internal fuel tankage, but mostly left empty and occupied by structural ribs rather than weapons or fuel cells)

It's also a bit like the Spitfire situation: the Meteor had tons of R&D poured into it with many modifications to make it perform better rather than just abandoning it in favor of the Vampire early on (which probably would have developed more quickly had the Air Ministry poured funding and high priority on it like they had the Gloster/Whittle/Rolls Royce projects).

To its credit the P-59 program DID end up with an exemplary safety record compared to Gloster or Lockheed's jet programs.

 

[GregP]

Curtiss WAS cruising along with little in the way of new designs. The XP-46 and XP-60 were basically extended P-40 designs. So was the XP-62. The family resemblance is way too strong. It looks like an overgrown P-36, and the P-40 was just a liquid-cooled P-36. To me the XBTC looks like another itteration, albeit with a different wing shape.

Let's say Shortround and I don't see this the same. Now THERE's a surpise, huh?

Either way, they didn't make the cut, so it's no big deal. They didn't make the cut because their products didn't perform. The XF-87 Blackhawk was just another in a long line of underwhelming designs. It didn't even LOOK modern, at least to me. At least the P-40 looked the part when it came out.

Don't get me wrong here, I like the P-40 and really believe the XP-40Q could have gone into production a LOT sooner than it actually flew. But Curtiss wasn't apparently interested in quantum leaps in performance or they would have been working on developments a LOT sooner.

Curtiss killed themselves with an unbroken line of adequate but not good-performing aircraft. Don Berlin left Curtiss, according to his son, when he wasn't allowed to "develop" the P-40 into a better fighter. His son does a very good presentation that generates a lot of questions. I've seen him at the Planes of Fame, but there were a LOT of people asking questions and we volunteers know that the public comes first. When questions were over we went out and flew our P-40N for the crowd.

Grumman didn't operate that way. They were working on the Hellcat when the Wildcat was into early deliveries and only made minor tweaks when the Koga Zero was found on Akutan Island, were working on the Bearcat a bit after delivering Hellcats and also had the Tigercat in work at the same time. Both flew and got into service before the war's end even if not MUCH before. They were at the top of their game right up through the F-14 Tomcat ... which didn't prevent them from being gobbled up in a corporate grab.

It's almost like the future we see in the original Rollerball movie, where the big corporations rule the world. Not quite ... but we seem to be headed that way.

 

[kool kitty89]

My point was that the P-40/P-36 was ALREADY a design in the same class as the Bf 109 and Spitfire with some advantages and disadvantages. (the main disadvantage of the airframe itself being weight: namely a result of the more stringent American structural standards -including the USAAC's 12G ultimate specification; the larger fuel capacity added to that as well) On top of that, service P-40s had to make do with moderately to significantly less power at all altitudes than their European contemporaries. (the closest case was probably comparing the P-40/B/C to the Spitfire Mk.I and Bf 109E where the V-1710-33 wasn't far behind and the P-40 had a better ram air intake than the 109 or spitfire -and possibly better engine streamlining)

The Spitfire and 109 would have gone nowhere without consistent and substantial engine upgrades: the P-40 never got those (XP-40Q aside). The engine the P-40N was fielding in 1943 had generally poorer all-around performance than what the Spitfire Mk.V had fielded over 2 years earlier while the preceding P-40F hadn't entered service in any number until around the time the 2-stage Merlin powered Spitfire IX was already entering service. Prior to that the P-40D and E were stuck with worse performance than the preceding B and C due to weight and drag increases with only modest 110 HP mil power increase up to a lower critical altitude and no added performance at altitude. (the larger radiator and stronger reduction gears did allow for a good deal more maximum power without overheating or stripping gears but until official WEP rating that was only possible through overboosting engines out of spec -had the 54" Hg manifold pressure WEP rating been cleared back in 1941, the P-40D/E and P-39D might have gained stronger reputations for performance at low altitude)


Given the Army's stance on engine development and particularly the state of affairs with the V-1710, Curtiss really would have been better off targeting other engines entirely when moving forward towards a P-40 successor or possibly aiming on a twin engine V-1710 powered aircraft (potential better to the P-38 ) given the bulk/drag of a turbo installation on a single-engine aircraft wasn't really worthwhile with the V-1710. (might as well go radial there and save some weight/cooling complexity if you're going to be stuck with turbo and intercooler bulk either way)

They could have tried a more streamlined turbocharged R-1830 big radials really seemed the best bet in 1939/40 though and at the time that would mean the R-2600 and R-2800 both ... not R-3350 unless Wright had drastically shifted development resources sooner. Had the XP-46 project focused on either a new airframe or a heavily modified P-36 descended airframe (likely with little/no direct compatibility but perhaps some features to make switching the production lines more efficient) optimized for the R-2600 or R-2800 it might have been more compelling compared to their own competing P-40D evolution while potentially taking advantage of their ongoing research into improved radial engine streamlining in the XP-42. (which didn't re-emerge until much ado and fiddling with the many faces of the XP-60) I'd throw the R-2180 in there too for potential next-generation radial fighter engines, but that one was a dud in hindsight. (for the time, considering that along with the R-2600 in the 1939/1940 timeframe seems perfectly reasonable though, with the R-2800 still further off)



The only other thing that hasn't really come up is a turbocharged P-36 taking advantage of the slimmer, cleaner airframe than the P-43, but the intercooler+turbo ducting might end up making that a wash anyway. (the 2-stage R-1830 still seems like a better trade-off there, particularly with the lingering turbocharger troubles present early-war)

 

[GregP]

You are correct above. The P-40 wasn't a bad plane, and I like it. It never got the engine it deserved. The Allison is a GREAT engine and did NOT suffer from lack of development. It suffered from lack of power increases coincident with the development. Many different models had the same ratings, but reliability and longevity were increased.

It made a good 1100 - 1200 HP for a long time and later got to 1,325 - 1,600 HP. People were actually USING it at 75" MAP and getting good power, but only in the Soviet Union and China with some of the guys in the AVG, such as General (Ret.) John Allison (no relation to the engine company at all). He said he demonstrated the P-40 at 75" MAP regularly. In the standard USAAF, people mostly stayed within the factory limits.

So it didn't get a power increase of substantial note until late in the game. It is VERY interesting to me that all the racing Merlins that win at Reno are using Allison G-series rods. They aren't really Merlins anyway since they have aftermarket rods, pistons, sometimes valves, cams, mags, ADI, and other assorted improvements. But the base engine is a Merlin and it is a damned GOOD base engine.

The Allison CAN make power and CAN turn WAY faster than 3,000 rpm. The tractor pull guys turn them at 4,600 rpm and they don't break .... but it's for a short time. Aircraft engines have to run for the entire mission. So ... a P-40 pilot COULD turn it faster ... up to about 3,600 rpm ... at which point he would be close to stretching and maybe losing the prop due to breakage, not to mention possible sonic issues. Had the Allison been cleared to 3,400 rpm in normal service with an attendant gearing change to account for prop speed, the power would have ratcheted upward a bit.

Yes, I know it didn't in widespread use, but it DID in occasional use. Therefore I feel it could have been power-bumped if the company had only DONE it. Alas, history has spoken and they didn't.

Had they thrown a 2,100 HP, 2-stage Merlin into one with NO other changes, it would go from 360 mph to 426 mph with nothing other than the power increase at the same altitude and faster up higher. Change the aerodynamics a bit and give it a better prop (necessary) and the top speed may have been quite competitive with the great fighters of the war. It could NOT have done any harm for the climb rate either.

But ... Curtiss soldiered on with the P-40 staying with the Allison at stock power levels. They MAY have been directed that way, but the possibilities for improvement in the airframe were always there and include airfoil as well as other changes in the design to make it better.

I'll say the P-40 never did get it's requisite amount of development and the XP-40Q series of 3 planes were only a teaser of what might have been had the management at Curtiss had their collective heads out of their collective rumps.

I do NOT know the contemporary political situation and so have no real insight into what went on during the decision-making meetings at Curtiss ... but they were rather obviously not in the company's best interests in the end.

They also would have HAD to abandon the Curtiss Electric 3-blade prop for a better unit ... but that's another post.

 

[Balljoint]

The P-40 was a bit altitude and power challenged as well as heavy. But the robust standards did give it good dive acceleration and superior roll performance. Through the early China and desert campaigns these attributes –with the appropriate tactics- gave it the ability to best the best of the opposition. With certain pilots, this seems to be true also in the Soviet theater.

To Curtiss's discredit, it, as well as Bell, politicked during the original design against a bulkier, more cumbersome properly boosted Allison for fear of it compromising their sleek designs. 15,000 was thought to be more than adequate.

 

[kool kitty89]

The P-40 was a bit altitude and power challenged as well as heavy. But the robust standards did give it good dive acceleration and superior roll performance. Through the early China and desert campaigns these attributes –with the appropriate tactics- gave it the ability to best the best of the opposition. With certain pilots, this seems to be true also in the Soviet theater.

It was more the aerodynamics of the control surfaces that allowed better high-speed control rather than structural limits.

To Curtiss's discredit, it, as well as Bell, politicked during the original design against a bulkier, more cumbersome properly boosted Allison for fear of it compromising their sleek designs. 15,000 was thought to be more than adequate.

It was the USAAC that refused to fun Allison's supercharger development and was initially even reluctant to introduce the 8.8:1 medium altitude supercharger gearing. (rather than only producing the low-altitude/turbocharger optimized 7.48:1 gearing)

Had they had full support and funding from the start, the issues with the 9.6:1 gear should have been worked out much sooner and the auxiliary supercharger stage would have been introduced much sooner as well. (the intake kinks might have been avoided or fixed as well ... partially ignored due to being less significant with turbocharging and low added compression provided by the 7.48:1 impeller speed -the intake bottleneck became a bigger issue with the 8.8:1 and especially 9.6:1 superchargers, though perhaps not meaning as much for the 2-stage variants)

It made a good 1100 - 1200 HP for a long time and later got to 1,325 - 1,600 HP. People were actually USING it at 75" MAP and getting good power, but only in the Soviet Union and China with some of the guys in the AVG, such as General (Ret.) Davey Allison (no relation to the engine company at all). He said he demonstrated the P-40 at 75" MAP regularly. In the standard USAAF, people mostly stayed within the factory limits.

Commonwealth use in North Africa and possibly the PTO noted use of overboost as well, but this was in the context of the P-40E and K and in the 66-70" boost range, with the latter only possible at sea level. 60-66" at low level seemed to be the more useful limit though I believe Allison formally limited the -73 of the P-40K to 60" and 56" on the older -39. It just took several years to get those official ratings. If the USAAC/AAF had been under the same pressure as the RAF from 1939 onward, it might have changed things somewhat but even pre-war the USAAC had tended towards more conservative design constraints.

As I've mentioned before, I'm not sure how 75" manifold pressure would be possible without significant overrev and ram at SL with the 8.8:1 supercharger ratio and would lead to detonation if attempted on the 9.6:1 engines unless they were rev limited to maybe somewhere around 2800 RPM. (approximately the same supercharger speed as an 8.8:1 engine pushed to 3200 rpm)

I believe the Tomohawk's V-1710-33 was limited mainly by the reduction gear strength (overboosting tending to cause stripped gears), the later -39 limited mostly by the crankshaft (overboosting tending to cause failures there), and I'm not sure if the stronger crankshaft of the -73 was still the limiting factor or not.

The most consistent power gains in the V-1710's operational life appear to be with the P-38, though even there not pushed into WEP ratings nearly as rapidly as British engines tended towards. (I'm also unsure if Allison's eventual 2000 HP 75" MAP clearance for the P-38L using 100/150 fuel ever extended to USAAF operational clearance)


As far as the USAAF goes it SHOULD be noted that the V-1650-1 lacked a WEP rating as well and didn't formally adopt the high emergency boost employed operationally by the Hurricane II. (or similarly on the Spitfire V's Merlin 45) The P-40F and L should have been faster than the M and N even with a bit of added weight (less dramatic when the P-40N was loaded down with full armament and fuel load unlike the stripped-down initial production configuration). The P-40F also should have had more power down low in WEP than the P-40E or K, at least complying with the official 56/60" manifold pressure limits.


All that said, even with the added conservative margins for safety, with more funding for exhaustive testing and R&D (and actual interest in extended supercharger designs beyond turbo installation back before the V-1710 even entered mass production) the engine should have competed far better and should have been a better investment than most or all of the Army's hyper-engine projects. (especially the XI-1430)

The Allison CAN make power and CAN turn WAY faster than 3,000 rpm. The tractor pull guys turn them at 4,600 rpm and they don't break .... but it's for a short time. Aircraft engines have to run for the entire mission. So ... a P-40 pilot COULD turn it faster ... up to about 3,600 rpm ... at which point he would be close to stretching and maybe losing the prop due to breakage, not to mention possible sonic issues. Had the Allison been cleared to 3,400 rpm in normal service with an attendant gearing change to account for prop speed, the power would have ratcheted upward a bit.

Is any of that done with the F series engines that lacked the additional counter weighing on the crankshaft? (I think it was the G series that introduced 3200 RPM take-off)

I have seen pilot and (I believe) engineer or possibly mechanic/crew chief notes from RAF operations noting the smoother running of the V-1710 compared to the merlin and ability to run smoothly at lower RPM for more efficient cruise. I have no idea how well it would have coped with heavy abuse being officially cleared for emergency use, but I do wonder how far the engines might have been pushed if rated as aggressively as the RAF/Rolls Royce seemed to. (how far might the C series have been pushed if it had been in the same situation as the Merlin III in the BoB?)

Had they thrown a 2,100 HP, 2-stage Merlin into one with NO other changes, it would go from 360 mph to 426 mph with nothing other than the power increase at the same altitude and faster up higher. Change the aerodynamics a bit and give it a better prop (necessary) and the top speed may have been quite competitive with the great fighters of the war. It could NOT have done any harm for the climb rate either.

Given the P-40 had both more space for fuel from the start and a larger margin for structural strength along with good aerodynamic qualities, I'd even argue it would have seen significantly greater gains than the Spitfire's engine evolution. (it'd stay a heavier plane, but the gradual weight creep would likely make up a smaller percentage of overall aircraft weight leaving the 1945 P-40 and Spitfire variants much closer in overall weight than the 1940 ones)

The P-51 just ended up better in nearly every way than the P-40, so it made such comparisons superfluous. (though I'd still argue a P-40 derivative might have been a better use of those war-time 2-stage allison engines than the P-63, more useful for the USAAF at least -ie something the USAAF might actually find operationally useful -shorter ranged than the P-51 but still decently ranged compared to the P-36 and with the added centerline hardpoint over the P-51 to make it more flexible as a fighter-bomber -also a

They also would have HAD to abandon the Curtiss Electric 3-blade prop for a better unit ... but that's another post.

The P-39 actually got 4-blade props on some of the later production models but seemed to cope poorly with the added torque ... not good on a plane with finicky spin characteristics. The P-40 might have handled it better, though. (being a heavier and generally more stable aircraft)

 

[GregP]

Ho Kool Kitty,

I worked at an Allison shop for about 2 years and it is VERY possible, standing still on the ground, mounted to the back of a Ford truck, with a Hamilton Standard club prop. Gen (Ret) John Allison came by several times and told us how he sold Chenault on the P-40. It involved demonstrating it at 75" MAP. When you did that, the P-40 sort of "woke up" and flew just great, according to General Allison.

Gen. Allison mentioned 3,400 rpm as his demo setting. He passed away about 3 weeks after his visit and we were glad we had an Allison ready for test that we could let him start up and help break in. Out break-ins were generally about 4 - 8 hours at 1,200 - 2,700 rpm and idle up to about 48" or so.

But Joe has a left-turn demo unit that he keeps for airshows that is all broken in. We ran it at the General's setting and it was pulling the Ford F-350 dually truck backwards with the wheels locked and we quickly backed off rather than chase the truck. Fortunately, if wasn't moving very fast, but the front wheel did start to come off the ground. When one did and it started moving it was time to back off.

We laughed about that for weeks. My only complaint was that I ws the one who had to reset the club prop's six blades for left hand rotation ... but that was a small price to pay for the show.

 

[gjs238]

Don Berlin left Curtiss in December 1941.
Was that a large reason for the fall of Curtiss?

Don Berlin left Curtiss, according to his son, when he wasn't allowed to "develop" the P-40 into a better fighter. His son does a very good presentation that generates a lot of questions. I've seen him at the Planes of Fame, but there were a LOT of people asking questions and we volunteers know that the public comes first. When questions were over we went out and flew our P-40N for the crowd.

Interesting, good reply to the initial query.

 

[Shortround6]

To some extent Curtiss went to the Casino and and rolled snake eyes several times in a row.

I am not sure how much of the P-36/40 carried over into the P-46. The P-46 was 1/12 feet shorter, had 3 feet less wingspan (and it was not clipped on the ends), had a kinked leading edge to accommodate the the inward retracting landing gear and had slats outboard in front of the ailerons. the fuselage .50 cal guns were mounted a bit above where the Early P-51 fuselage guns were mounted and not on top like a P-40. That is due to the reduction gear. The Light weight prototype is supposed to have reached 410mph (or at least gotten close) while the fully equipped prototype dropped to 355mph. Something doesn't seem quite right there. Few, if any,fighters lost 50mph going form unarmed prototype to full service equipment. 10-30mph yes but 50-55mph? Either the 410mph was wrong or the 355mph was wrong, or something was very wrong with the prototype. Army lost interest, in part due to the armed prototype flying in Sept of 1941 and the World situation was such that the Army couldn't afford the loss in production a change over from the P-40 to the P-46 would have entailed. The Army didn't have several months to test fly the XP-46 and figure out where some of the speed went ( the increase in weight is usually blamed but most aircraft could take that kind of additional load without slowing down anywhere near that much). That was the first roll of the dice.
The second roll was the XP-53. Keep the P-40 fuselage (unlike the P-46) and stick a laminar flow wing on it. Unfortunately Curtiss tried to cthe deck a bit by picking the Army's fair haired wonder boy engine, The Continental XIV-1430. This doomed not only the XP-53 but every other plane that was intended to use it. To be fair the 275 sq ft wing needed more power than the Allison was giving at the time. I don't know if it was Curtiss or the Army that came up with the idea of eight .50 cal guns in the wings. If you want Thunderbolt armament you need a close to Thunderbolt sized plane to carry it.
The 3rd dice roll was the XP-55 and we know how that turned out. It's Allison engine was the 2nd choice (if not 3rd) after the P W 24 Cylinder H-2600 sleeve valve was canceled and perhaps a brief flirtation with the Continental XIV-1430. Even if the got the unorthodox aerodynamics to work they were down hundreds of horsepower over the intended engine/s. Many of the programs overlapped.
The 4th roll of the dice was the XP-60. Replace the Continental engine in the XP-53 with a single stage Merlin and keep the 275sq ft laminar flow wing. The Army goes for this one in mid Nov 1940. Only a couple of months after ordering the R-2800 powered P-47 off the drawing board. Inspite of using inward retracting gear it actually flies 11 days before the armed XP-46. Here is where things get a bit strange. Using a Merlin that was supposedly not making full rated power the XP-60 is supposed to have gone 387mph at 22,000ft which means it was 20-25mph faster than a production P-40F using the same model engine. Unfortunately the XP-60 was about 5-600lbs heavier than a P-40F and almost 1000lbs heavier than a P-40E (and had 16% more wing area) so the climb performance and ceiling were a bit lacking. Weight was due in part to the eight .50 cal armament. Army requirement or Curtiss trying to equal Republic?
Army then goes into a bout of self doubt and rapid changes of mind (everything but wearing a hair shirt under their uniforms) as they decide the XP-60 needs more power in the form of a turbo-charged Allison, and orders 1950 of them, then within weeks decides the Allison, even with turbo isn't powerful enough. Before they can reach a decision the Japanese hit Pearl Harbor the production question puts the lid on the P-60's coffin ( Build P-40s which aren't quite good enough or build nothing while we sort o the P-60?). The Coffin lid isn't nailed shut as the army cancels the production order but orders 3 more prototypes, one with a GE Turbo Allison, one with a Wright turbo charger on an Allison and one with the Chrysler V-16. The original XP-60 was pretty much a P-40E/F with a new wing. These 3 prototypes were pretty much the XP-60 wing with new fuselages. With our great hindsight it is not surprising that the wright turbo came to nothing and the Chrysler V-16 took much longer to reach flight status than planned. Both airframes got P W R-2800 radials while armament was cut to six guns and then four guns in an effort to get the weight under control.

Now maybe if Curtiss had used a smaller laminar flow wing with only 4 guns on the P-40 Fuselage they might have gotten a plane closer in performance to the Mustang and had production models flying in the summer of 1942.

Curtiss double up on their bets and kept rolling the dice with the XP-62 and the Navy fighter. The Army issued the specification that lead to the XP-62 in Jan of 1941. Curtiss submitted their proposal in April of 1941. Army spec call for eight 20mm cannon or TWELVE .50 cal guns. Between the Pressure cabin, the R-3350 engine the counter rotating propellers, the 420 sq ft wing (an A-20 had 465sq ft) and the guns/fuel the plane wound up about 1 ton heavier than a P-47.

This certainly doesn't look like a company putzing along building slight variations of the P-36/40 to me. It does look like a company a little too desperate for work (or too confident in their own abilities?) to tell the customer that what they want isn't possible and to scale back their fantasy aircraft to reality.

Curtiss in 1939-42 was also building SNC trainers, the AT-9 twin engine trainer,the C-46 (working on the unlamented C-76, another blow to the Curtiss reputation) The Helldiver and the Seamew. The last four aircraft probably did more to Curtiss's reputation and long term prospects than any of the "failed" fighters.

 

[Graeme]

Don Berlin left Curtiss in December 1941.
Was that a large reason for the fall of Curtiss?

According to one author (Joe Mizrahi - Wings. Volume 25 No.2) Donald Berlin's (described as a difficult man to work with) departure from Curtiss was not the reason for the fall of Curtiss. Curtiss was falling slowly well before this due to administrative problems...

 

[GregP]

Yeah, what HE said above.

 

[Shortround6]

According to one author (Joe Mizrahi - Wings. Volume 25 No.2) Donald Berlin's (described as a difficult man to work with) departure from Curtiss was not the reason for the fall of Curtiss. Curtiss was falling slowly well before this due to administrative problems...

Author has a rather strange view of business. Yes the O-52 was useless for modern warfare but then so were a number of it's contemporaries. If the customer says that is the airplane he wants, was it up to Curtiss to say "NO, you are wrong, we won't build it" ? That type of aircraft had been being built for years, the Douglas O-38 was built in greater numbers than the P-26 fighter.

Douglas went on to build several parasol monoplane "observation planes" totaling around 120-130 aircraft.

Their replacement, North American O-47

was purchased in greater numbers than the P-36 by the USAAC.

Germans bought HS 126s by the Hundreds.

and we have beaten the Lysander to death

French were build twin engine aircraft for this role and yet Curtiss is supposed to have either convinced the Army they were wrong and turned down the contract or given the money back after building the planes?

Wiki has a rather different story about the SBC-4 dive bombers. Regardless of wither the navy returned the planes to Curtiss as "outmoded", and please remember that the Navy was operating biplane Grumman F3F fighters from carriers over a year later, or wither this was a ruse to get some combat planes to France in a Hurry the Martinique "thing" is a bit twisted in the Article. The planes were loaded on the aircraft carrier Bearn along with 21 Hawk 75s?P-36s (?) 25 Stinson 105s and 5 Brewster Buffaloes for Belgium. (numbers vary slightly in different accounts). France fell while the Bearn was enroute and it sailed to Martinique. Martinique sided with Vichy France as did the crew of the Bearn. Both the US and the British kept "watch" on Martinique at times (British had two cruisers on watch from July until Nov of 1940).
Now was Curtiss supposed to give the money back? and to who? The US government or the Vichy government who had possession of the planes or to the "Free French". How was sit the fault of Curtiss that the planes wound up in Martinique? Should every manufacturer of war goods only been paid for items that made it to the intended destination and just forfeited any money for planes, tanks, trucks, ammo, blankets sunk by U-boats or bombers in route?

Yes Curtiss took on too many projects but then it was the Army and Navy handing them out. The British Air Ministry sometimes passed on giving 3rd or 4th contracts to some firms because the Ministry judged the Firm/s in question didn't have enough capacity to build them in a timely manner. Of course the US Army gave money to Preston Tucker too

 

[Graeme]

Good information there!

If the customer says that is the airplane he wants, was it up to Curtiss to say "NO, you are wrong, we won't build it" ?

I got the impression from the article, maybe I'm wrong, that Curtiss was in a rut design wise and accepting orders for obsolete aircraft which they were happy to oblige and encourage. All fine and good - but then the war abruptly ends and they lose massive contracts. Another author, Peter M Bowers, points out that Curtiss was particularly hard hit because they never planned for a postwar market, in particular, civil aircraft.

Got another scan, this time from an article on the XF-87. Would it be fair to say that the USAF by 1948 had little respect for the Curtiss management?

 

[Shortround6]

I think the reverse is actually true. Curtiss was accepting orders for "New" aircraft that took too long to develop and too often didn't perform as promised. This kind of "company performance" makes it hard for the customers to keep placing orders on faith.

I don't know if the O-52 performed as promised or not. But it wasn't Curtiss's fault the basic specification was out of date. Curtiss was responsible for a lot of the SB2C Helldivers initial woes and long development. Curtiss took on the job of designing a wooden transport aircraft (the C-76) that came out over weight, under performing and tended to come apart in flight. The saga of the Seamew and it's "replacement" by older Seagulls taken from depots and 2nd line units certainly didn't help Curtiss's reputation. Wartime C-46s had a tendency to blow up in flight. Post war civil conversions got vented wing roots/wings to vent spilled fuel. Why that took years to fix is a bit of a mystery.
While some of the Curtiss fighter projects were certainly of advanced concept at the time they started they took too long and under-performed when done. Curtiss refused to tell customer that the intended payload was simply too much ? (eight 20mm cannon?).
By 1946-47 Curtiss simply had a rather dismal track record. Stuffing up being a second source for the P-47 didn't help.