Should the US have used either the Vultee P66 or Curtis-Wright CW21?

[pinsog]

Considering how allied aircraft faired against the Japanese early in the war, should the US have built either the Vultee P66, which had good speed, 340 mph, or should it have built the Curtis-Wright CW21? The CW21 had an excellent rate of climb, supposedly 4,500 fpm with an 850 hp engine The CW21 was a bit slow at 314 mph, but if the Wright Cyclone had been bumped up to 1100-1200 hp like the P&W in the Wildcat, it should have been a match for about anything with outstanding climb, maneouverability and good speed. Sort of beating the Japanese at their own game. If not why not?

 

[vikingBerserker]

I believe the US used a number of P-66's and the IIRC the CW21 sold to China were used by the AVG.

 

[pinsog]

That is what I understand also. Should the US have built the and used them for themselves?

 

[GregP]

The CW-21's that got sent to the AVG were lost enroute to delivery, hitting a mountain.

The Dutch East Indies got 24 CW-21B's. They claimed 4 victories but were overwhelmed by sheer numbers of Japanese planes.

They might have made a difference, and I personally LIKE the design, but it never showed much in the way of potential other than a few victories against many losses. Perhaps if it had been available in some numbers it might have done something.

I like the P-66, but they needed orders ... from the home armed services, and they weren't forthcoming.

 

[Shortround6]

Considering how allied aircraft faired against the Japanese early in the war, should the US have built either the Vultee P66, which had good speed, 340 mph, or should it have built the Curtis-Wright CW21? The CW21 had an excellent rate of climb, supposedly 4,500 fpm with an 850 hp engine The CW21 was a bit slow at 314 mph, but if the Wright Cyclone had been bumped up to 1100-1200 hp like the P&W in the Wildcat, it should have been a match for about anything with outstanding climb, maneouverability and good speed. Sort of beating the Japanese at their own game. If not why not?

From Wiki, take for what you think it is worth.

" The lightweight construction of the Curtiss-Wrights gave rise to structural problems, and several aircraft were grounded by cracks in the undercarriage, and were still awaiting repair when war with Japan began on 8 December 1941"

and "With its light construction, radial engine, low wing loading, limited pilot protection and lack of self-sealing fuel tanks, the CW-21B was the Allied fighter most similar to the opposing Japanese fighters"

the improvement by fitting a later model Wright Cyclone may not be as great as it might appear. The Engine used in the CW-21 was a pre-war engine and the naming/nomenclature was a bit different. Engines in the 30s were often called by their MAX continuous rating and that is the case here. The engine was good for 850hp at 6000ft (34in at 2100rpm) for as long as the fuel lasted. Take-off rating was 1000hp at 2200rpm at 41in for 5 minutes. The 4500fpm climb may have been achieved using this rating?
The engine also weighed 1115lbs, over 200lbs less than the later 1100-1200hp engines.

Engine data can be found here: http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgMakeModel.nsf/0/9d8387f8163ad7d98525670e0065ae06/$FILE/ATTZCGXO/TC154.pdf

More info on the CW-21 can be found here: http://www.warbirdforum.com/cw212.htm

Please note the parts were both radio and oxygen are called "optional" equipment by Curtiss which certainly calls into question the performance of a model equipped to 'normal' US standards.

The P-66 had already been evaluated by the British in the Fall of 1940 (after they were embargoed) and not wanted by them except as advanced trainers. They were reported as having some (unspecified?) structural problems in US service. They may have achieved their performance figures without armor or self sealing tanks.

 

[GregP]

Here's a civilian counterpart that has a LOT of CW-21 in it, the CW-22. It is right next to the tail of the DC-3 and it makes me want to go flying.


View attachment 238883

 

[Jabberwocky]

Considering how allied aircraft faired against the Japanese early in the war, should the US have built either the Vultee P66, which had good speed, 340 mph, or should it have built the Curtis-Wright CW21? The CW21 had an excellent rate of climb, supposedly 4,500 fpm with an 850 hp engine The CW21 was a bit slow at 314 mph, but if the Wright Cyclone had been bumped up to 1100-1200 hp like the P&W in the Wildcat, it should have been a match for about anything with outstanding climb, maneouverability and good speed. Sort of beating the Japanese at their own game. If not why not?

US assesments of the P66 considered the aircraft unfit for combat (at least with US forces, some were cleared for export to the UK [where they would have been used as trainers] and [temporarily] Sweden and a few ended up with the Chinese airforce).

From the little bit I've seen about it, the aircraft had the following major faults:
Slow speeds at altitude (340 mph at 15,000 ft);
Light construction and an insufficient armour scheme;
Inadequate engine cooling (due to closely cowled radial);
Marginal lateral stability (partially solved by increasing the size of the rudder);
Antiquated construction methods (steel tubing and even wooden structural members a la the Hawker Hurricane)
Weight creep (the production version was 1150 lb heavier than the prototype)

The US had plenty of other designs in production or in the pipeline (P-43, P-39, P-40, P-51, P-47) that offered all the performance of the P66 and then some.

 

[davebender]

Mass produced USA day fighter aircraft.
P-38
P-39 / P-63
P-40
P-47
P-51
F4F
F6F
F4U

USA Light / medium bombers.
A-20
B-25
B-26
TBF
SBD
SB2C

Germany began the war with a single mass produced day fighter aircraft. Britain began the war with two models.

Japan began the war with a single mass produced (by Japanese standards) IJA fighter and a single mass produced IJN fighter aircraft.

IMO the USA had far too many air models in mass production. Now you want to add more? If P66 and / or CW21 are mass produced they should be ILO something else.

 

[vikingBerserker]

Here's a civilian counterpart that has a LOT of CW-21 in it, the CW-22. It is right next to the tail of the DC-3 and it makes me want to go flying.


View attachment 238883

It was also use by the Dutch military to what extent I am not sure. I have a book with pictures of captured Dutch aircraft by the Japanese and there were a number of CW-22s.

 

[GregP]

There is a pristine example in the Evergreen Museum in Oregon, and it made me want to jump in and fly it. What a beautiful example of an art deco radial executive plane that could keep up with a lot of fighters of the day. Simply aviation in one of its best forms. The plane used to fly regularly but hasn't in more than 10 - 15 years.

I'd LOVE to restore and fly it. The "restoration" would probably consist of wiring, engine, maybe hydraulic hoses and the prop seals ... and, of course, new tires. The airframe itself looks like new ... but thath CAN conceal major issues, as I well know.

 

[pinsog]

I didn't mean to produce either for the whole war, I meant just build one or both of them until the F6F, F4U and P38 could replace it. The CW21 could outclimb a Nate or a Zero, or a Hurricane, Spitfire or ME109 for that matter, so it could have fought the early Japanese fighters on equal footing. Neither the CW21 or the P66 should be built in place of midwar or late war fighters.

 

[davebender]

Do you realize how many V12 powered fighter aircraft the USA produced during 1941? We were building P-39s and P-40s by the thousands. Mustang airframe was also available with hundreds produced for Britain.

If you want an inexpensive fighter aircraft powered by plentiful R1820 or R1830 radial engine then P-36 was in production during 1940. P-36 is a fair match for IJA Ki-43 and more then a match for Ki-27.

 

[Ivan1GFP]

The CW-21 simply wasn't competitive from many different aspects.
The maximum speed was way too low.
The firepower was also too low (Two machine guns).
Aircraft carried no armour at all.
The climb rate was overstated.

There is an article from somewhere in the 1970s describing this aircraft pretty much as Curtiss Advertising.
I believe it was in "Air Power" magazine though I am not absolutely certain. It was in one of the few magazines I bought at the time.

It was nimble and that was probably its only truly superior characteristic.

- Ivan.

Attached is a screenshot of a Flight Sim model I started building many years ago but still haven't finished yet.

 

[oldcrowcv63]

The P-36 apparently enjoyed a good reputation among the DEI-Af pilots in Java.

If you want an inexpensive fighter aircraft powered by plentiful R1820 or R1830 radial engine then P-36 was in production during 1940. P-36 is a fair match for IJA Ki-43 and more then a match for Ki-27.

Seems like the P-36 high altitude performance might have benefited from replacing the P&W 1830 SG205 with the F4F-4's two-stage supercharged, P&W 1830-76 or -86? Is there a reason why this couldn't have been done to give the USAAF a better high altitude capability than wither the P-40 or P-39 could manage? Was the production being monopolized by F4F-3 4 production?

 

[davebender]

What do you mean by "high altitude"?

Most Pacific aerial combat took place below 20,000 feet. P-36 supercharger optimized for 18,000 feet should work just fine.

 

[Shortround6]

Do you realize how many V12 powered fighter aircraft the USA produced during 1941? We were building P-39s and P-40s by the thousands. Mustang airframe was also available with hundreds produced for Britain.

If you want an inexpensive fighter aircraft powered by plentiful R1820 or R1830 radial engine then P-36 was in production during 1940. P-36 is a fair match for IJA Ki-43 and more then a match for Ki-27.

Lets see if we can correct a few things.

The US Built 3560 v-12 powered fighters in 1941, 2289 of them were P-40s, only 138 were P-51s. Every P-36 you make in 1941 is one less P-40 as they were built on the same production lines and used a lot of the same tooling. (Yes they added more lines for the P-40 but the P-36 lines/ equipment was not standing idle.

As for your earlier post,

You bring in practically EVERY US single seat fighter of the entire war, and then compare that list to what other countries had in "in production" at the start of the war only. Hardly a fair comparison.

You also leave out the fact that while The British, the Germans, the Japanese, the French and the Russians had twin engine multi-seat day fighters in production or development. the US stopped with the Airacuda and didn't come close to fielding another one for the duration of the war.

As for the Japanese building just one JAF fighter? Both the Ki 44 and Ki 61 were being worked on in 1940 in response to 1939 requirements.

The British had just two fighters? well since you count the US Navy fighters why don't you count the FAA fighters. How about counting the Whirlwind? How about counting the Typhoon? Built to a pre-war specification it was in production before the Allison powered Mustang. Maybe it shouldn't have been given it's initial problems but it was.

as for your Bomber list?

The twins won't operate of carriers on a regular basis and the single engine navy planes don't have the range to perform the twins job.

The US may have had more types than some other nations but not to extreme that you are trying to paint.

Even the Germans were "planning" on adding a 2nd single seat fighter when they went to war (earlier than planned) with the first flight of the Fw 190 in June of 1939.

 

[nuuumannn]

Someone nailed it when they mentioned numbers. Without the numbers of aircraft in theatre there was no hope for the Allies. A few more CW-21s and P-66s in American hands wouldn't have made much difference in the end.

 

[Shortround6]

Quite right, a few extra squadrons (3-6) isn't really going to affect things.

And turning these "light" planes into planes that US would judge "combat ready" is going to come at a price.

For those of us who have AHT please look at the P-40, The P-40 gained about 400lbs empty weight going from the 5th production P-40 to the P-40C, empty means without guns, armor, oxygen etc but in this case does include 71 lb of radio. A lot of the increse was due to the self sealing tanks. P-40s used three tanks, a different plane with different tanks might very well show less of an increase.
The P-40 B,C had 93 lbs of armor/BP glass. Later P-40s got more. Later P-40s also roughly doubled the weight of the radio installation.

I would note that the Brewster Buffalo Used by Finland used exactly the same engine used by the CW-21 and and the increase in power was not enough to keep up with the increase in weight. The F2A-3 used a 339lb 10'3" prop with hollow steel blades compared to the 262lb 9'0" Aluminium blade propeller used on the Finish 239s. Granted the Buffalo porked up more than most early fighters but just stuffing in the later Cyclone/bigger prop, a modest amount of armor and self sealing tanks, radio and oxygen could run the weight of the CW 21 up by 600lbs or better (13%). I am not sure what that does to the "G" rating/safety limits or landing loads.

 

[oldcrowcv63]

What do you mean by "high altitude"?

High altitude in December, 1941 thru about December 1942 was anything above ~24k to ~27k' feet. The frequent favorite altitudes of IJN G4M bombers attacking pretty much where ever they chose. A6M escorts typically took up positions about 3,000 ft above their charges, putting them about 27-30,000'.

Most Pacific aerial combat took place below 20,000 feet. P-36 supercharger optimized for 18,000 feet should work just fine.

The most devastating and uncontested attacks were as described above and nothing the allies fielded in any numbers could reach them. The Hurricanes might have but the types sent to Southeast asia were the ground attack variant, not the interceptor. As I understand it, apparently they weren't in sufficient numbers and weight reduction measures weren't totally effective. P-40 ceiling was about 27,000'. When the P-40Es encountered aircraft at lower altitudes they acquitted themselves reasonably well, but suffered heavily in the initial months because they couldn't get above the A6Ms and were barely able to reach the G4Ms.

I imagine a supercharger optimized for 18k' might have helped some but from charts it looks like the Allison -39 single-stage SC the P&W -86 first stage kicks in about 12-15 k' while the second stage of the P&W kicks in about 20k" I haven't found any P&W charts for a single stage supercharger so not sure where the G205 or similar engine (for example P&W 1830-90) kicks in.

from: http://curtisshawk75.bravepages.com

"The Hawk 75 never benefited from the later R-1830 versions, including the single-stage, two-speed supercharged R-1830-90, let alone the two-stage, two-speed R-1830-76, which gave the Grumman F4F Wildcat a new lease on life. The presence of this engine allowed the Wildcat to take on the A6M Zero at higher altitudes.
The empty weight of the Army's standard P-36C was 4,620 lbs. empty, 5,734 lbs. loaded. Weight for the folding-wing F4F-4 version were 5,895 lbs. empty and 8,762 lbs. loaded, although the earlier F4F-3 was somewhat lighter. In a Navy proposal Curtiss estimated a top speed of 351 MPH for a navalized Hawk equipped with the -76 engine. "

 

[Civettone]

Pinsog, why don't you add the Republic P-43 to that list ??



Kris