Curtiss-Wright: Loss of Don Berlin and downfall

[GregP]

The P-47 was every bit the fighter the P-51 was. It had different strengths and weaknesses, but it was formidable. After the paddle-bladed prop came out, it was definitely the better performer of the two above 25,000 - 30,000 feet.

When I mentioned having Curtiss concentrate on other projects, I was assuming that would come after the P-40 was getting a bit dated. So my suggestion would not have affected early P-40 production. But I'm not sure they would have gotten to the "N" model before I would have asked them to pursue other avenues of endeavor.

I'd have disbanded Brewster or had their engineers assigned to other companies. Their internal quality control was laughable.

 

[kool kitty89]

I'd have disbanded Brewster or had their engineers assigned to other companies. Their internal quality control was laughable.

Yeah, had the Navy (or any branch of the US Government) investigated the situation sooner they'd probably have taken more drastic action. Brewster seemed to manage small scale production well enough, but was in no shape to expand that infrastructure (be it trying to force higher volumes out of their small initial facilities or trying to manage expanding to new plants) and aside from being outright disbanded/liquidated, it might have just made sense to keep them mainly as an engineering consulting firm with only limited manufacturing abilities. (enough to prototype their own aircraft in a timely manner and make small production runs, perhaps still handling export orders)

Having the Naval Aircraft Factory take over production of the F2A like it had the SBA/SBN might have changed the story of the Buffalo. (unless the Navy DID attempt that and Brewster wasn't forthcoming for a license, but that seems unlikely even with Brewster's level of management woes)

Expanding the Naval Aircraft Factory's capacity would have been a much better investment than expanding Brewster orders and expecting them to be capable of managing expansion.

That or encouraged/compelled a merger/buyout of Brewster by Grumman. (or another manufacturer, but Grumman seems the obvious choice not just as the major USN aircraft producer, but also given the relatively close proximity of Brewster and Grumman headquarters)






As for a Curtiss Corsair, if it could have been put into mass production in a reasonable amount of time, it should at least have made a superior fighter and fighter-bomber than the P-40 of the same time period as well as a better fighter-bomber/dive bomber than the A-36 or A-31. ( 'better' in the all around operational effectiveness sense at least, not necessarily in pure bombing accuracy -compared to the A-31 or raw top speed -compared to the A-36 at low altitude )

Perhaps one of the few notable 'improvements' Curtiss might (or should) have added would be bomb racks and possible drop tank plumbing. (also potentially replacing the unprotected wing tanks with self sealing fuel cells -likely of somewhat reduced capacity)

Any model intended for high altitude combat would obviously need to retain the 2-stage R-2800, but for low/medium altitude fighter/bomber or intruder work or low/medium altitude patrol, interceptor, or escort duties, single stage 2-speed R-2800 or R-2600 powered variants should have still been serviceable and useful.

 

[GregP]

I'd have stopped production of "low-altitude" engines and concentrated on 2-stage or 1-stage+turbo units. Anytime a "low altitude" fighter needs to go high and fight, it can't. A high-atitude plane CAN funtion well down low. There is some justification for a low-altitude plane if there is air superiority but, otherwise, I can't really think of one in the ETO.

In the PTO, CBI, and maybe MTO ... maybe not ... there was some room for lower-altitude capability planes.

By "planes," I mean fighters. Why field a P-39 / P-40 when you can field a plane with altitude capability? If that's all you HAVE, use it, then start making better ones and deploying them to replace the single-stage units. Maybe even have a wholesale swap out and return the older airframes to be upgraded in the powerplant department.

 

[kool kitty89]

In the PTO, CBI, and maybe MTO ... maybe not ... there was some room for lower-altitude capability planes.

The MTO would be where the low-altitude optimized 7.48:1 supercharged Allison powered A-36s were allocated ... as fighter bombers in the ETO, they'd probably have done better to stick witht he 8.8 supercharger of the Mustang I/Ia. (maybe the 9.6:1 engines even)

But we're not just talking about single-speed superchargers, but 2-speed ones, so the comparison becomes more akin to the Merlin XX powered Hurricane II and P-40F/L depending on the 2-speed R-2800s and R-2600s in question. (some were tuned for lower critical altitudes than the Merlin XX, though that would still have the advantage when higher take-off power is needed while still having high gear for at least medium altitude capability -unlike the A-36 or Sptifire LF Mk.V)

I might be mistaken, but Wright also seemed to get better performance out of their single supercharger stages than P&W did. The R-1820 seemed to have an edge over the 1830 there (unless I'm mistaken and it was only the single SPEED R-1830s that fared worse), but then also the R-1820's development fared better than the R-2600's. (and the R-2600 never seemed to mate with turbochargers well for some reason)

Cranking out more 2-stage R-2800s would be ideal, though.

 

[GregP]

I like both the 1820 and the 1830 myself. But almost everyone has their preferences. Mostly it falls down to what is in the plane you fly ... these days you wouldn't be swapping engines unless more than one was approved for the airframe. Some ARE approaved for multiple types. The Bt-13 / 15 comes to mind. One was a Wright and one was a Pratt.

As long s I'm "what-iffing," I might as well ask Allison to design an integral, 2-stage supercharger, and to leave room for speed changes if indicated in testing. Can't leave ANYTHING alone, huh?

 

[kool kitty89]

I like both the 1820 and the 1830 myself. But almost everyone has their preferences. Mostly it falls down to what is in the plane you fly ... these days you wouldn't be swapping engines unless more than one was approved for the airframe. Some ARE approaved for multiple types. The Bt-13 / 15 comes to mind. One was a Wright and one was a Pratt.

With the Wildcat the switch between the two wasn't particularly messy either given the already large fuselage diameter, and the early Wildcats and Martlets downgraded to single-stage engines seem to have fared better on the R-1820s than 1830s (or at least close enough to make the increased cowling diameter inconsequential). And obviously the more powerful R-1820 of the FM-2 proved a net prerformance gain, especially in acceleration and climb.

It's not like the case of the Curtiss Hawk 75 where the performance margin of the R-1820 on some export models made it obvious that the altitude performance outstripped the added drag (and quite noticeably bulkier nose on that rather skinny fusealage). The F2A was never tested with an 1820, but given it's smaller size, I wonder if it would have benefited more than the Wildcat did. (in spite of its stubby, barrel shaped fuselage, it's still actually slimmer than the Wildcat, rather obvious by the fact that the F2A's engine cowling is very nearly the widest point on the entire aircraft, while the F4F clearly bulges out in the middle considerably further even on the Cyclone powered models)


But as to the 1830 vs 1820 argument, the 1820 was a much older design that saw near complete re-designs several times in its life (retaining little more than cylinder dimensions) while the 1830 was both newer and not stretched as far in development (perhaps in part due to the R-2000 taking over for higher power needs -granted, one could see the R-2000 as as much an evolution of the 1830 as later 1820s were of their predecessors). Given the diameter advantage, it's still odd Grumman went from R-1535 to R-1820 rather than R-1830. (including possibly the simpler single stage 1830s if weight was a serious problem -possible given the originally intended small engines)

As long s I'm "what-iffing," I might as well ask Allison to design an integral, 2-stage supercharger, and to leave room for speed changes if indicated in testing. Can't leave ANYTHING alone, huh?

Well, most of my suggestions were actually downgrades to the basic F4U-1 configuration in the event that airframe production capacity exceeded 2-stage R-2800 production volumes and/or for export models. (akin to what happened to the export Buffaloes and Wildcats/Martlets) Plus the single-stage engines would cut costs (especially the 2600) and at least slightly close the gap further between the much cheaper P-40 itself. (even if the P-40 was obviously less capable in range, load hauling ability, and sheer performance, the added value alone doesn't always sell that well ... especially when you've got both the military and congress to work through, not to mention foreign buyers -or lend-lease production)

Pushing R-2600 powered Corsairs off to lend-lease might make the most sense.

 

[Shortround6]

OK, R-2600 powered F4U?
When?
Why?
Lend-lease to who and when?

The 1700hp R-2600 doesn't really show up much different than the 1850hp R-2800. So you don't really pick up anything in timing. The R-2600 is bigger in diameter. The Corsair was designed for an 1850hp engine minimum but two stage so it had good power at 18-22,000 ft. Cutting the power by 10% at even the lower altitudes means you have lighten the plane up by 1100-1200lbs to get near the same climb. Compared to service F4Us you are talking 15% less take off power, 400hp less at 10-14,000ft and with aux supercharger in high gear the F4U-1 had about 600hp more than the R-2600B did at around 22,000ft.
Even if you go for the low altitude ground pounder, the R-2600 gives up too much and it never got a WEP rating or water injection. Please compare the R-2600 power at 12,000ft to the Allison, then figure in the added weight, the added drag and then see what real advantage the plane would have over a P-40. Unless you stay really, really low AND have good escorts flying top cover, this doesn't look like a good option.

 

[Koopernic]

I like the idea of the P-75. Its possibilities as a long range fighter bomber able to drag heavy loads such as torpedos, bombs, large rockets ultra long distance and replace aircraft such as the B-25, B-26 were probably not appreciated. It would be self escorting and thus highly efficient. It would have been better than the P-51 in over water missions.

Such matters weren't appreciated then.

A Naval style microwave radar on the wing, a second crew member would increase its versatility both as a night fighter and as a night time bomber and torpedo bomber against shipping.

Big is beautiful.

 

[Shortround6]

It would be self escorting and thus highly efficient. It would have been better than the P-51 in over water missions

There really isn't any such thing as "self escorting". You can use one squadron of fighter "X" to escort another squadron of fighter "X" carrying bombs though. If our long range fighter bomber has to drop it's bombs to defend itself then it is a mission kill for the defenders, no bombs dropped on the intended mission target. Mission has to be flown again the next time weather permits. Assuming it is not a shipping target and the the target is now out of range.

Competition in the bomber category wasn't so much the B-25 and B-26 but the A-26. Sure you can replace a twin engine bomber plane of a certain age with a newer twin engine "fighter-bomber" and get most of the range/payload but bumping a bomber that uses the same knowledge (aerodynamics and structure) is going to be a bit tougher.

Often big is beautiful, Grumman F7F first flew within 2 weeks of the first P-75 and the first P-75 looked like a dogs breakfast.

 

[GregP]

If Big is beautiful, I really like the Boeing XF8B-1, 1st flight in 1944.

Imagine 1,000 of those headed anywhere with bad intentions.

 

[kool kitty89]

I like the idea of the P-75. Its possibilities as a long range fighter bomber able to drag heavy loads such as torpedos, bombs, large rockets ultra long distance and replace aircraft such as the B-25, B-26 were probably not appreciated. It would be self escorting and thus highly efficient. It would have been better than the P-51 in over water missions.

Such matters weren't appreciated then.

A Naval style microwave radar on the wing, a second crew member would increase its versatility both as a night fighter and as a night time bomber and torpedo bomber against shipping.

Big is beautiful.

Wouldn't much of that also be applicable for the P-38, including the night fighter role?

And self-escorting is a bit of an odd issue: without dedicated escorts, you'd be forced to release bombs and drop tanks in order to properly evade or engage interceptors, effective for pilot and aircraft survival, not so good for operational effectiveness.

Now if you mean self-escorting in that the same model planes could be configured for both bomber and escort dueties and bombed-up fighter-bombers could be escorted by other aircraft of the same type, that would make more sense while allowing the ratio or fighters to bombers vary from mission to mission and save on both fuel and bomb resources. (with the added benefit of the 'bombers' STILL having the option to drop their load early and fight or run just as well as the escorts)


The P-51, P-47, and F4U would have some potential there too, but the P-51 would have issues carrying a drop tank and bomb due to shifting weight issues as fuel is consumed so most likely would only use internal fuel. The P-47 and F4U have more options for ordinance, and the F4U in particular has its bomb/tank racks all on the centerline to minimize weight shifts more like the P-38.

The P-38 still has the advantage of being able to carry a massive 300 US gal drop tank along with an additional 1600 or 2000 lb bomb (depending on the model).


The P-38 also should have been able to be adapted to carrying anti-tank and anti-material cannons in the nose. The M4/M10 of the P-39/P-63 would be useful against some 'soft' but heavy targets without the performance penalty or inaccuracy that wing-mounted rockets posed and the higher powered M9 37 mm cannon should be possible to fit as well and useful against some armor. (beyond what the hispano was already capable of)

 

[Koopernic]

Wouldn't much of that also be applicable for the P-38, including the night fighter role?

And self-escorting is a bit of an odd issue: without dedicated escorts, you'd be forced to release bombs and drop tanks in order to properly evade or engage interceptors, effective for pilot and aircraft survival, not so good for operational effectiveness.

There really isn't any such thing as "self escorting". You can use one squadron of fighter "X" to escort another squadron of fighter "X" carrying bombs though.

The problem with fighter bombers based on say the Me 109, Spitfire P40 is that these aircraft were too small to carry a bomb load that was worthwhile without loosing performance; speed and range. They don't have range to begin with.

A Fisher P-75 or Boeing XF8B-1 has range, even with bombs. They are also not going to slow down much with a load.

When the Luftwaffe worked out their bomb shackles they had a fighter in the Fw 190G that could haul a bomb to a target deep in enemy territory 1000km away and return. Speed loss was about 50km/hr which was almost restored with C3 einspritziung. They used the aircraft with blind bombing systems and it was only a moderately sized fighter.

As for the Big fighters such as the P-75 and XF8B-1
1 Long range even with bombs, same as medium bomber.
2 Speed loss limited to such a degree that interception was unlikely anyway (compare that to slowly having 6 men in a medium bomber try to fight this way in their way in and then out again) so a mission kill is unlikely.
3 Can start to carry sophisticated devices for instance radar on the wing to find and 'blind' attack enemy aircraft and enemy shipping with bombs and torpedos.
4 blind bombing systems such as Oboe, Gee-H, Micro-H allow a single engine aircraft to level bomb.
5 Electronic navigation to help the pilot find his way home.
6 such large aircraft could carry a second man if necessary.

The final nail in the coffin for medium bombers was the development of toss bombing sights.

Bombing of targets behind enemy lines was possible with such aircraft but I saw them more as replacing medium bombers rather than strategic bombers.

These were all coming in toward the end of WW2 had the big aircraft been available sooner the systems would have been developed sooner. The P-75 didn't have to wait for a R-4360.

There is no such thing as a medium bomber anymore. There are F-15E doing that job.

 

[Milosh]

A 500SC and 2 300l. drop tanks resulted in a speed loss of 50mph to 56mph, not 50kph, depending on the ETC rack used.

This was at climb and combat power.

 

[Shortround6]

The problem with fighter bombers based on say the Me 109, Spitfire P40 is that these aircraft were too small to carry a bomb load that was worthwhile without loosing performance; speed and range. They don't have range to begin with.

True but then they weren't part of the discussion to begin with. P-40 was never "official" tested with large bomb loads. large being relative but their are photos of them carrying six 250lb bombs. The Last "N"s were rated for three 500lb bombs and there are reports of them using 1000lb bombs in Italy. Given a long runway a late model P-40 might be able to carry two 500lb bombs and a drop tank.

A Fisher P-75 or Boeing XF8B-1 has range, even with bombs. They are also not going to slow down much with a load.

1/2 right. The Boeing XF8B-1 could carry at least a couple of bombs inside. Put a couple of drop tanks on the outside for the early part of the mission and you might get an impressive range (beware of some internet ranges, being a Navy plane a lot of the range figures are for around 190mph at low altitude.) XP-75 was only rated for a pair of 500lb bombs. Granted it might not have taken much work to increase that but an internal bay was out. Engines and fuel taking up most of the volume near the the CG. The more "stuff" you hang outside the worse the performance gets.

As for the Big fighters such as the P-75 and XF8B-1
1 Long range even with bombs, same as medium bomber.
2 Speed loss limited to such a degree that interception was unlikely anyway (compare that to slowly having 6 men medium their way in and then out again) so a mission kill is unlikely.
3 Can start to carry sophisticated devices for instance radar on the wing to find and 'blind' attack enemy aircraft and enemy shipping with bombs and torpedos.
4 blind bombing systems such as Oboe, Gee-H, Micro-H allow a single engine aircraft to level bomb.
5 Electronic navigation to help the pilot find his way home.
6 such large aircraft could carry a second man if necessary.

The Big fighter being able to carry the same bomb load as far as an equivalent medium bomber takes a bit of swallowing. Or more than a bit. Being able to come close to previous generation bombers is lot more believable but then you are comparing planes in service world wide in 1942 to planes that would NOT have entered squadron service until mid/late 1945 at best. Try comparing the "BIG" fighter to the A-26 or the B-42.

3750 pounds over a range of 1850 miles (?). It would hold four 2000lb bombs inside.

The final nail in the coffin for medium bombers was the development of toss bombing sights.

That nail took until the early to mid 50s even begin to be a reliable method.

These were all coming in toward the end of WW2 had the big aircraft been available sooner the systems would have been developed sooner. The P-75 didn't have to wait for a R-4360.

No, it had to wait for a V-3420 with two stage supercharger when Allison was having trouble building V-1710s with two stage superchargers. One of the P-75As was bailed back to Allison under a no payment contract for further engine development work after The P-75 contract was canceled so perhaps it's performance figures should be taken with a few grains of salt.

There is no such thing as a medium bomber anymore. There are F-15E doing that job.

This rather confuses the march of progress. AN F-15E weighs empty only about 400lbs less than a Martin B-26 at mean weight. One might also consider that the B-47E bomber only had about 75% of the installed power of an F-15E.
One might also want to consider the actual bomb loads, speed and radius of a B-66B with only a bit more power than 1/3 the power of an F-15E and being about 30 years older. One also wonders what Ed Heinemann and Douglas could have done with engines that weighed about 75% of the engines used in the B-66 while giving about 40% more thrust without afterburner and with better fuel consumption.

Comparing airplanes of different generations/types and claiming that they way they are used now shows what could have done then (30-40 years before) ignores a whole lot of things.

 

[kool kitty89]

The problem with fighter bombers based on say the Me 109, Spitfire P40 is that these aircraft were too small to carry a bomb load that was worthwhile without loosing performance; speed and range. They don't have range to begin with.

A Fisher P-75 or Boeing XF8B-1 has range, even with bombs. They are also not going to slow down much with a load.

When the Luftwaffe worked out their bomb shackles they had a fighter in the Fw 190G that could haul a bomb to a target deep in enemy territory 1000km away and return. Speed loss was about 50km/hr which was almost restored with C3 einspritziung. They used the aircraft with blind bombing systems and it was a moderately sized fighter.

The Bf 109, P-39, P-40, Typhoon, and Fw 190 were all less capable fighter-bombers than the likes of the P-47 and F4U in terms of combination of performance, load, and range (the Tempest and Fury might be more competitive but still shorter legged on the whole and I'm not entirely sure where the F6F might fit in).

The P-38 takes the load+range capabilities a bit further and the F7F further still while both were adaptable to nightfighter roles too. (similar for the De Havilland Hornet as well)

The Fw 187 might have developed into something along the same lines as well, likely more akin to the P-38 than the later F7F (or Hornet).

The Me 410, Ar 240, and Mosquito as bombers/fighter-bombers seem to fit in more of an odd middleground there as none was really capable of performing day fighter duties, unlike the P-38. (granted, the Hornet and F7F were no longer capable day fighters by the time they actually saw combat, but as late WWII aircraft they were more competitive even during the transition to early jets)

OK, R-2600 powered F4U?

Even if you go for the low altitude ground pounder, the R-2600 gives up too much and it never got a WEP rating or water injection. Please compare the R-2600 power at 12,000ft to the Allison, then figure in the added weight, the added drag and then see what real advantage the plane would have over a P-40. Unless you stay really, really low AND have good escorts flying top cover, this doesn't look like a good option.

I was thinking in terms of both the British and Soviet lend-lease P-40 deliveries in the event sufficient R-2800 production wasn't initially available. Admittedly, this seems unlikely (in as far as Corsair production outstripping R-2800 production). The 1850 hp single-stage R-2800 would seem a more realistic alternate choice there. I was admittedly also thinking in comparison to the R-2600 powered P-36/P-40 derivative and the Corsair airframe being better suited to the engine in terms of existing dimensions, aerodynamics, and fuel capacity. (and potential external load carrying capacity)

I guess there's still probably more useful places for R-2600s at the time though, at least if you assume both A-20s, B-25s, A-31s, SB2As, and SB2Cs are all more effective bombers and attack aircraft all around than R-2600 powered Corsair derivatives in their respective roles. (or, rather in the SB2A's case, just better allotted to one of those other R-2600 powered aircraft ... likely the same for the A-31, and also admittedly some of those used older engines before the Corsair would likely see service -or be more crippled by the 1600 hp limitation- ... or wilder ideas like trying to cram those 1939/40 vintage R-2600s into F4F or P-36 airframes)

I suppose the P-36 airframe mated to an R-2600 might make a semi-decent early war fighter-bomber in the sense the Jabo Fw 190s later did, but it really seems like the size and capacity of the F4U (and dive bombing capability) would make more sense in the attack role. (other than that, it's just the existing R-2600 powered bombers that would be better for those roles ... the question was more whether the F4U might manage better than SOME of those as well as SOME roles the Allison powered P-40 performed historically while possibly being a bit faster flying/climbing/turning/rolling than the existing P-40E)

 

[Shortround6]

I suppose the P-36 airframe mated to an R-2600 might make a semi-decent early war fighter-bomber in the sense the Jabo Fw 190s later did, but it really seems like the size and capacity of the F4U (and dive bombing capability) would make more sense in the attack role. (other than that, it's just the existing R-2600 powered bombers that would be better for those roles ... the question was more whether the F4U might manage better than SOME of those as well as SOME roles the Allison powered P-40 performed historically while possibly being a bit faster flying/climbing/turning/rolling than the existing P-40E)

The P-40 seems to get a bit maligned at times. Yes it was a bit underpowered and a bit overweight but it actually wasn't too bad drag wise. It was within 10-15mph of a Spitfire V at 20,000ft when powered by a Merlin, the extra 1000lbs of weight are what killed the climb and altitude performance.
Sticking a high drag radial on the airframe unless you can come up with an installation close to the FW 190s isn't going to help much because you are just sucking up a lot of the extra power fighting the extra drag.

A P-40F was 'supposed' to do 350mph at 12,800ft in low blower. A P-40E was supposed to be good for about 340mph. A F4U-1 was 'supposed' to do about 360mph at 13,000ft using 1650hp (normal or max continuous rating) it would go faster using Military power. The 1700hp for take-off R-2600 was only good for about 1400hp at 13,000ft at Military rating. Cut 250hp from the Corsair and see the speed drop. You might get a bomb truck out of it but you no longer have a fighter after the bombs are gone, at least not a very good one. You have the same problem as the P-40, too much weight for not enough engine. Even if you can lighten up the Corsair by 1000lbs or so by using the lighter R-2600, a smaller prop and less fuel you then have a 10,200lb plane with a 1400hp engine at 13,000ft while the real F4U-1 had 1800-1850hp up to about 18,000ft for its 11,200lb weight. The P-40E had 1100hp or so for 8000lbs. Power to weight winds up within a few % and the R-2600 Corsair is well behind the curve on drag compared to a P-40E.

If you are going to be slow and climb like crap you might as well bite the bullet and stick the rear gunner in.

 

[kool kitty89]

A P-40F was 'supposed' to do 350mph at 12,800ft in low blower. A P-40E was supposed to be good for about 340mph. A F4U-1 was 'supposed' to do about 360mph at 13,000ft using 1650hp (normal or max continuous rating) it would go faster using Military power. The 1700hp for take-off R-2600 was only good for about 1400hp at 13,000ft at Military rating. Cut 250hp from the Corsair and see the speed drop. You might get a bomb truck out of it but you no longer have a fighter after the bombs are gone, at least not a very good one. You have the same problem as the P-40, too much weight for not enough engine. Even if you can lighten up the Corsair by 1000lbs or so by using the lighter R-2600, a smaller prop and less fuel you then have a 10,200lb plane with a 1400hp engine at 13,000ft while the real F4U-1 had 1800-1850hp up to about 18,000ft for its 11,200lb weight. The P-40E had 1100hp or so for 8000lbs. Power to weight winds up within a few % and the R-2600 Corsair is well behind the curve on drag compared to a P-40E.

Hmm, yes, and what might be gained in (maybe) better wing loading/higher lift airfoil compared to the P-40 would tend to be a loss in dive and zoom climb performance. (the higher weight of the standard F4U-1 would be an advantage there too given weight = thrust in a dive)

If you are going to be slow and climb like crap you might as well bite the bullet and stick the rear gunner in.

And at that point, adapting the likes of the SBD to use an R-2600 would probably make more sense. (and an R-2600 powered land or carrier based F4F should perform better than the similarly powered F4U too -and match far better to the engine than the P-36's slim/low drag frame and smaller wing)

The P-36 airframe really was best mated to a V-12 engine ... putting as much effort into low drag radiator/oil cooler configurations on the P-40 as they had radial cowlings on the XP-42 probably would have been one of the better investments Curtis could have made. (compared to British fighters, the delay in WEP ratings hurt low/middle altitude performance a good deal too -including V-1650-1 WEP)

 

[Shortround6]

Grumman had studied (two different design numbers at least) putting a R-2600 in the F4F, they came to the conclusion it needed a new airfame.

One problem you have with a lot of these "stick the R-2600 in it" schemes is that the US did not have a 4 bladed propeller in production during the planing stages of some of these schemes. They got one with the B-26 but there must have been some reason the F4U used that huge 3 bladed prop and they jumped though all the hoops with the bent wing to help fit it. Now maybe you don't need the big diameter prop if you stay at low level where the air is thick but you don't use a prop designed for 11-1200hp on a 1600-1700hp engine either. You not only get a heavier prop but the bigger diameter will call for longer landing gear which means.........
F4Fs had trouble taxiing as it was.
SBD's seemed to lag a bit behind on getting the latest R-1820s. Sticking and extra 600lbs of dry engine in the nose might not be that easy either.

 

[kool kitty89]

Grumman had studied (two different design numbers at least) putting a R-2600 in the F4F, they came to the conclusion it needed a new airfame.

One problem you have with a lot of these "stick the R-2600 in it" schemes is that the US did not have a 4 bladed propeller in production during the planing stages of some of these schemes. They got one with the B-26 but there must have been some reason the F4U used that huge 3 bladed prop and they jumped though all the hoops with the bent wing to help fit it. Now maybe you don't need the big diameter prop if you stay at low level where the air is thick but you don't use a prop designed for 11-1200hp on a 1600-1700hp engine either. You not only get a heavier prop but the bigger diameter will call for longer landing gear which means.........
F4Fs had trouble taxiing as it was.

Indeed, I dug up the old discussion on R-2600 powered fighters and saw the extensive details on all that, particularly between your and Tomo's posts. The Wildcat does indeed have a bunch of limitations that would be made worse with the R-2600 installed (particularly those related to the landing gear: track, length, supension, and retraction mechanisms) For the R-2600 to be properly utilized it would mean more or less a similar progression in development that the F6F later saw. The only problem there is that didn't go beyond paper until 1941 and didn't fly until 1942 at which point the 2-stage R-2800 was the obvious choice for mass production.

An earlier Hellcat of sorts might have actually made sense to bring into service with the R-2600 had its design and testing started 2-3 years earlier, allowing an R-2600 powered Hellcat to enter production around the same time as the F4F-4 did historically. (possibly earlier if they'd foregone the F4F-3 entirely and started on the Hellcat -or equivalent new airframe- back in 1937/38, but then you'd need the F2A to hold the fort in the interim and for smaller/escort carrier use, and that too might have worked out fine if not limited to using Brewster manufacturing; adapting it to the 2-stage R-1830 would help make the F2A more useful as well)

I suppose that would be the point too: the R-2600 only really makes sense for a purpose-built fighter optimized for it AND developed early enough to take advantage in the initial development and mass production leads (of the 1600 and 1700 HP models) over the R-2800. So the Corsair doesn't really make sense there either ... rather odd the Hellcat still ended up targeting the 2600 in '41/42 for that matter.

As a final note on the Wildcat: the only other possibly useful engine might have been the R-2000 but that would be in the similar vein as the R-1820 the FM-2 already used historically, not really available any sooner though smaller in diameter and more power without water injection. That and introducing a powered landing gear retraction mechanism. (given the torque required for that manual crank, it seems like introducing a small electric motor to drive it would be pretty straightforward and simplify take-off and landing procedures)
That and there's an argument that the performance loss between the F4F-3 and F4F-4 wasn't worth the added utility gained from the modifications.



Also, as far as Curtiss aircraft are concerned: the 2-stage R-1820 would probably be the only real competitor to the V-1710 in terms of P-36/P-40 developments. (and with the conventional P-36 cowling, would be slower than the P-40 below 15000 ft, dive worse, but maybe climb and turn a little better -we've been over the trade-offs here before though) Definitely more interesting than an R-2600 powered P-36 derivative at very least.

 

[gjs238]

<SNIP> the US did not have a 4 bladed propeller in production during the planing stages of some of these schemes. They got one with the B-26 but there must have been some reason the F4U used that huge 3 bladed prop and they jumped though all the hoops with the bent wing to help fit it. Now maybe you don't need the big diameter prop if you stay at low level where the air is thick but you don't use a prop designed for 11-1200hp on a 1600-1700hp engine either. You not only get a heavier prop but the bigger diameter will call for longer landing gear which means.........

How did the F6F deal with this issue?