Most 'Underrated' Aircraft of WW2?

[michael rauls]

P-40Ns were used for lead lease to a host of countries, they were issued to training squadrons in the US (the manual assured new pilots that if they could handle the P-40 in training they could handle whatever fighter the combat squadron they were posted to had) and as a sad commentary, of the last few hundred built, they went directly to storage/scrap. When you are building over 200 a month it is a little hard to turn off the flow over night.
P-40s flew in

Thats what I was kinda thinking. That they must have, aside from training, been largely for export but while there were still many units using them in 44 and a few in 45 it just doesn't seem like enough to utilize that kind of production but maybe with training and replacement taken into account it was.

 

[michael rauls]

P-40Ns were used for lead lease to a host of countries, they were issued to training squadrons in the US (the manual assured new pilots that if they could handle the P-40 in training they could handle whatever fighter the combat squadron they were posted to had) and as a sad commentary, of the last few hundred built, they went directly to storage/scrap. When you are building over 200 a month it is a little hard to turn off the flow over night.
P-40s flew in

The line you wrote about the last few hundred p40s going directly to storage / scrap made me think what a crying shame it is that almost nobody recognized how valuable these war bird would become( and I don't mean in a monetary way) and didn't think to preserve more than a dozen or two of most types if even that. Some even less or none at all. This may be one of those hindsight things but to me it really looks obvious. Out of respect for the guys that flew them if nothing else.

 

[Conslaw]

IIRC, the Tang had to (or it was decided to) sink this Kingfisher on the grounds that the weight of the rescued flyers compromised the flying surfaces. Even so, it was marvelous performance by the plane and pilot. (There is a well-preserved Kingfisher on the Battleship North Carolina Memorial in Wilmington, North Carolina.)

They (and the other seaplanes like the PBY, SOC, etc.) are truly overlooked.

Here's one such example of the Kingfisher in action at Truk Lagoon, 1 May 44. Launched from USS North Carolina (BB-55), they picked up downed aviators (nine aboard for this photo - two being inside) in the lagoon and not having enough interior room for the airmen in order to get airborn, "taxiied" instead with them riding on the outside, out of the lagoon to a waiting lifeguard sub, which in this case, was the USS Tang (SS-306).

View attachment 501590

 

[GrauGeist]

IIRC, the Tang had to (or it was decided to) sink this Kingfisher on the grounds that the weight of the rescued flyers compromised the flying surfaces. Even so, it was marvelous performance by the plane and pilot. (There is a well-preserved Kingfisher on the Battleship North Carolina Memorial in Wilmington, North Carolina.)

The Kingfisher's floats had sprung a leak and was settling in the water from the rough-water landings and additional weight through rough seas during the extended taxiing. There was no way it could get airborne after offloading the rescued crewmen.

And agreed, it was a magnificent feat of determination by the Kingfisher's crew.

 

[michael rauls]

The Kingfisher's floats had sprung a leak and was settling in the water from the rough-water landings and additional weight through rough seas during the extended taxiing. There was no way it could get airborne after offloading the rescued crewmen.

And agreed, it was a magnificent feat of determination by the Kingfisher's crew.

This may be a little off the topic but just ran across something I think you might enjoy. It's an interview, told 2nd hand, with Franz Stigler who commanded Luftwaffe forces at the Palm Sunday massacre( I'm guessing you already know who he is). If you have not read this already it is definitely a must read and it is riveting! It's at aviation store.net.

 

[davparlr]

All the aircraft that held the line in the PTO in the first year of the war.
F4Fs
P-40s
P-39s

On a backburner battlefield strangled by lack of support, these aircraft and the men that flew them faced some of the most formidable and experienced fighter pilots in the world with airplanes that were uniformly far more maneuverable. Once techniques and experience matured, IIRC at the outbreak of the war, 100 AAF pilots, fresh out of pilot training, were diverted from the Philippines and sent to the south pacific, these aircraft blunted the onslaught of an overpowering enemy. By the time more advance aircraft became operational in the theater, the F4U in February, 43, the F6F in August of 43, P-38s arrived in August, 42, but in limited amounts, the Japanese had sustained a significant amount of loses of the irreplaceable cream of their aircrews and the tide had swung against them. A job well done and underappreciated.

Here are a few of the battles fought in the south pacific in 1942 and first part of 1943.

Coral Sea
Midway (not in the south pacific)
Eastern Solomon
Guadalcanal
Cape Esperance
New Guinea (a theater all its own with ferocious land, sea, and air battles for the full year)

There were many others where aircraft played little or no role.

Other underappreciated aircraft

• · While quite a few accurately identified the very capable A-20, the Lockheed Hudson seems to have gotten its nose stuck in a lot of interesting situations early in the war while it is basically ignored.

• · Short wing B-26. If the AAF had emphasized high speed, high wing loading piloting, which it had to do anyway in a few years, the short wing with its 35 mph top speed and its almost 50 mph cruise speed advantage, would have been even more formidable than the successful later model B-26s. Instead its reputation was very negative due mainly to poor training.

 

[Shortround6]

I agree with a lot of that but the B-26 is a mixed bag.
The short wing B-26 was usually being operated thousands of pounds lighter than the later big/tilted wing planes. This would usually mean less bomb load or range or both had they kept building the short wing planes.

See; http://www.wwiiaircraftperformance.org/B-26/B-26_Operation_and_Flight_Instructions.pdf

The B-26 went from an under 30,000lb aircraft to a max 37,000lb aircraft. Maybe 1500lb can be attributed to the bigger wing, tail, armor and increased armament?

 

[Venturi]

All the aircraft that held the line in the PTO in the first year of the war.
F4Fs
P-40s
P-39s

On a backburner battlefield strangled by lack of support, these aircraft and the men that flew them faced some of the most formidable and experienced fighter pilots in the world with airplanes that were uniformly far more maneuverable. Once techniques and experience matured, IIRC at the outbreak of the war, 100 AAF pilots, fresh out of pilot training, were diverted from the Philippines and sent to the south pacific, these aircraft blunted the onslaught of an overpowering enemy. By the time more advance aircraft became operational in the theater, the F4U in February, 43, the F6F in August of 43, P-38s arrived in August, 42, but in limited amounts, the Japanese had sustained a significant amount of loses of the irreplaceable cream of their aircrews and the tide had swung against them. A job well done and underappreciated.

Here are a few of the battles fought in the south pacific in 1942 and first part of 1943.

Coral Sea
Midway (not in the south pacific)
Eastern Solomon
Guadalcanal
Cape Esperance
New Guinea (a theater all its own with ferocious land, sea, and air battles for the full year)

There were many others where aircraft played little or no role.

Other underappreciated aircraft

• · While quite a few accurately identified the very capable A-20, the Lockheed Hudson seems to have gotten its nose stuck in a lot of interesting situations early in the war while it is basically ignored.

• · Short wing B-26. If the AAF had emphasized high speed, high wing loading piloting, which it had to do anyway in a few years, the short wing with its 35 mph top speed and its almost 50 mph cruise speed advantage, would have been even more formidable than the successful later model B-26s. Instead its reputation was very negative due mainly to poor training.

As said earlier, the reasons above are part of why the P-40 always remained a 1940/41 era aircraft. It was too profitable for Curtiss and too needed by the US, to be delayed at all in 1942 production. Even as dated as it was by 1942 European standards. By the time 1943 came around, there was no two-stage Allison to put in them and here comes the P38 and P47 with the turbo-supercharger... and in 1944 the Packard Merlin Mustang with the RR 2 stage setup.

My point was very simple, though - and it got expanded and dragged along alot further than I meant it to. My point was that the P40 airframe was not the dog it came to be reputed as. The original Tomahawk series were lighter than the Warhawk series by a fair margin and nearly as fast. They were a TON, literally, lighter than the P-51. Weight means a great deal in fighter combat as evidenced by the Bf109 and Spitfire, Yaks, etc. You can see the differences in the design from Tomahawk to Warhawk, as the Curtiss brass weighed in on design. Increased weight, increased size, aerodynamic problems introduced. Yes, a lot of the changes had to do with the 1710-33 to 1710-39 transition and shortening the reduction gearing, etc. But for the most part these changes were not done with an eye to improving the design but rather minimizing changes / expenses in production and in meeting USAAF regs / export compatibility. You would NEVER have seen a complex structure like the Spitfire's wing on a Curtiss assembly line! The P-40 remained a very inexpensive fighter as compared to later ones the USAAF fielded, throughout the war.

Had the design process across the P-40s life been better, more foreward thinking at Curtiss, had they instituted a two-gear supercharger on the Allison 1710-39 or later, like the Merlin 66 had (no two-stage engine-lengthening there), you would have had a P-40E with a lighter airframe ala Tomahawk which would mean better acceleration and climb as well as energy retention in maneuvers, it would have kept its excellent roll rate and avoided longitudinal instability, and had benign handling characteristics (unlike the P-39) - and would have remained the premier all-around single seat fighter until at least the P-51 arrived in numbers which was at the end of 1943, as the historical P40E did - just a lot better at its job.

That the moderately revised P-40Q with a engine similar in output to a 1944-45 Packard Merlin achieved results that were well above 400mph proves my point. And that's all I wanted to say.

 

[Venturi]

Ultimately the fact is that the motivation to improve the P-40 just wasn't there, at the highest levels. The Air Force brass wanted turbo-superchargers, and that was coming in the P-38 and P-47. Curtiss wanted to keep making money. Production was needed of EVERYTHING at max capacity. P-26's were trying to fight Zeros as the Curtiss assembly line cranked away in 1942. The result was that the P-40B/C which was actually an excellent design, became inexorably outdated by world standards even by late 1941 and the P-40E variant. Fortunately, it was still a capable, maneuverable, and flexible aircraft, and it could and DID produce good results. Who can say now that we are right to wish it had been developed further at the expense of producing more much needed fighters, even if they were somewhat dated? But the point remains, it COULD have been...

 

[Shortround6]

Curtiss built what the government wanted them to build.

I would really like to see some sort of proof as to how much money Curtiss was making and when. Contracts changed during the war. Grumman for example made a huge amount of money on the F6F. Gumman took until some time in the 1960s to make as much money in one year as they did in 1944, but this is misleading.
Grummans contracts where under constant review by government auditors and Grumman was not supposed to make more than 3% profit. However 3% profit on over 6000 F6Fs in one year is a lot of total profit, but is it excessive? Many other aircraft and defense contractors operated under similar contracts. If a company figured out to make a product cheaper, follow up contracts were amended to lower the price.
Perhaps Curtiss got around this and was profiteering? Or people are just looking at total revenue and not actual profit?

There are reasons the Warhawk weighed more than the Tomahawk and they don't have a whole lot to do with Curtiss sabotaging the Warhawk or incompetence in design or some of the other stuff being implied.
You want for or six .50 cal guns in the wings instead of four .30 cal guns you need beefed up wing structure. You want the ability to carry 500lb bombs under the wings you need beefed up structure.
You want to add guns, armor, self sealing tanks and still have a 12 G safety factor you need to beef up the structure.
You want to cool an 1150 hp engine instead of an 1040hp engine? maybe you need a bigger/heavier cooling system.
The wing group on a Hawk 75 for export went around 840lbs, The wing group on the Tomahawk went about 1000lbs, the wing group on a Warhawk went just over 1100lbs.

Curtiss, like Grumman, built airframes. The engines were bought and paid for by the Government under separate contracts and shipped to the aircraft factories.
The propellers were also provided by the government as were some of the instruments, the radios and some other gear.
Curtiss could suggest changes in the supplied equipment and if the government agreed and could get the contracts with the engine makers, propeller makers and instrument makers changed, and could supply the new/different parts to Curtiss then and only then could Curtiss change the production aircraft.
The government could make one or more airframes available to Curitiss to experiment on in regards to airframe details (change in tail or radiator location or even airfoil) and the government might even pay for such work if a decent proposal was put forth.

Curtiss was trying hard to come up with a successor to the P-40, unfortunately it wasn't up to Curtiss to pick and choose either the desired engine or the desired armament or some of the other details. The Government would put out proposals for a new fighter and would say they wanted the "new" fighter to use engine XX and to fly at 400mph and carry eight .50 cal machine guns. All to often Engine XX turned out to be a turkey
, from WIki
" The initial design contained in proposals to the United States Army Air Corps was for an aircraft based upon the P-40 design but featuring a low drag laminar flow wing, a Continental XIV-1430-3 inverted vee engine, and eight wing-mounted 0.5 in (12.7 mm) machine guns. This proposal was accepted and a contract for two prototypes was issued on 1 October 1940 with the aircraft designated the XP-53."

This was after the XP-46 and before the XP-55 Ascender. The XP-53 morphed into the P-60 series but it was caught in an ever shifting "what engine are they going to use" problem. The Army had made it pretty well known that they wanted to go to the Continental XIV-1430 engine and that the Allison was sort of a temporary fill in so designers of aircraft to replace the P-38, P-39 and P-40 should be thinking about using the Continental XIV-1430 and not just an improved Allison. Please note there were versions of the P-39 (the P-39E/P-76) the P-38 (turned into the P-49)

That were intended to use the XIV-1430 engine.
Unfortunately the XIV-1430 was a total dud and may designs either fell to the wayside or made mad scrambles for substitute engines.
The Continental XIV-1430 may be one reason the Army was not leaning on Allison very hard to to come up with either a two speed or a two stage supercharger.
Turbo XIV-1430s were supposed to be the answer.
Please note that the Army actually did a lot of the design work and Continental just served as an assembly/workshop. And the Army was as bad at paying Continental for work done in the 30s as they were at paying Allison.

 

[GrauGeist]

Ultimately the fact is that the motivation to improve the P-40 just wasn't there, at the highest levels. The Air Force brass wanted turbo-superchargers, and that was coming in the P-38 and P-47.

As has been exhaustively stated already, Curtiss put a tremendous effort into trying to upgrade the P-40. Actually more than they should have BUT contracts kept coming in for the P-40 and as long as Governments were wanting it, Curtiss was going to build it.

Curtiss wanted to keep making money.

So did every other aircraft manufacturer.
Grumman's F4F was used through to the end of the war. GM even continued to manufacture it until 1945, two years after Grumman stopped manufacturing it.
And the Wildcat was older than the P-40.

Production was needed of EVERYTHING at max capacity. P-26's were trying to fight Zeros as the Curtiss assembly line cranked away in 1942...

Wait, What?
The few Army P-26s at Pearl Harbor were caught on the ground and destroyed, only the P-36 and P-40 were able to engage IJN elements.
The USAAC P-26s in the Philippines were also caught on the ground. Only some Philippine Army P-26 aircraft, flown by Philippine pilots engaged the Japanese.
The bulk of USAAC fighter groups were already equipped with the P-40 and were in the process of phasing out the P-36 when the U.S. entered the war in December 1941.

 

[michael rauls]

Curtiss built what the government wanted them to build.

I would really like to see some sort of proof as to how much money Curtiss was making and when. Contracts changed during the war. Grumman for example made a huge amount of money on the F6F. Gumman took until some time in the 1960s to make as much money in one year as they did in 1944, but this is misleading.
Grummans contracts where under constant review by government auditors and Grumman was not supposed to make more than 3% profit. However 3% profit on over 6000 F6Fs in one year is a lot of total profit, but is it excessive? Many other aircraft and defense contractors operated under similar contracts. If a company figured out to make a product cheaper, follow up contracts were amended to lower the price.
Perhaps Curtiss got around this and was profiteering? Or people are just looking at total revenue and not actual profit?

There are reasons the Warhawk weighed more than the Tomahawk and they don't have a whole lot to do with Curtiss sabotaging the Warhawk or incompetence in design or some of the other stuff being implied.
You want for or six .50 cal guns in the wings instead of four .30 cal guns you need beefed up wing structure. You want the ability to carry 500lb bombs under the wings you need beefed up structure.
You want to add guns, armor, self sealing tanks and still have a 12 G safety factor you need to beef up the structure.
You want to cool an 1150 hp engine instead of an 1040hp engine? maybe you need a bigger/heavier cooling system.
The wing group on a Hawk 75 for export went around 840lbs, The wing group on the Tomahawk went about 1000lbs, the wing group on a Warhawk went just over 1100lbs.

Curtiss, like Grumman, built airframes. The engines were bought and paid for by the Government under separate contracts and shipped to the aircraft factories.
The propellers were also provided by the government as were some of the instruments, the radios and some other gear.
Curtiss could suggest changes in the supplied equipment and if the government agreed and could get the contracts with the engine makers, propeller makers and instrument makers changed, and could supply the new/different parts to Curtiss then and only then could Curtiss change the production aircraft.
The government could make one or more airframes available to Curitiss to experiment on in regards to airframe details (change in tail or radiator location or even airfoil) and the government might even pay for such work if a decent proposal was put forth.

Curtiss was trying hard to come up with a successor to the P-40, unfortunately it wasn't up to Curtiss to pick and choose either the desired engine or the desired armament or some of the other details. The Government would put out proposals for a new fighter and would say they wanted the "new" fighter to use engine XX and to fly at 400mph and carry eight .50 cal machine guns. All to often Engine XX turned out to be a turkey
, from WIki
" The initial design contained in proposals to the United States Army Air Corps was for an aircraft based upon the P-40 design but featuring a low drag laminar flow wing, a Continental XIV-1430-3 inverted vee engine, and eight wing-mounted 0.5 in (12.7 mm) machine guns. This proposal was accepted and a contract for two prototypes was issued on 1 October 1940 with the aircraft designated the XP-53."

This was after the XP-46 and before the XP-55 Ascender. The XP-53 morphed into the P-60 series but it was caught in an ever shifting "what engine are they going to use" problem. The Army had made it pretty well known that they wanted to go to the Continental XIV-1430 engine and that the Allison was sort of a temporary fill in so designers of aircraft to replace the P-38, P-39 and P-40 should be thinking about using the Continental XIV-1430 and not just an improved Allison. Please note there were versions of the P-39 (the P-39E/P-76) the P-38 (turned into the P-49)
View attachment 502709
That were intended to use the XIV-1430 engine.
Unfortunately the XIV-1430 was a total dud and may designs either fell to the wayside or made mad scrambles for substitute engines.
The Continental XIV-1430 may be one reason the Army was not leaning on Allison very hard to to come up with either a two speed or a two stage supercharger.
Turbo XIV-1430s were supposed to be the answer.
Please note that the Army actually did a lot of the design work and Continental just served as an assembly/workshop. And the Army was as bad at paying Continental for work done in the 30s as they were at paying Allison.

Was this similar to the procurement process in other countries? I would be fascinated to know the procurement process in Germany, Japan, and Britain and how it affected the ultimate characteristics of the aircraft they got.

 

[Shortround6]

Was this similar to the procurement process in other countries? I would be fascinated to know the procurement process in Germany, Japan, and Britain and how it affected the ultimate characteristics of the aircraft they got.

I don't know about other countries and even US procurement changed from before the war to during the war.

But in general an air force (army or navy or independent) put out a requirement for a new type of aircraft. It could be an open competition with any company being able to make a submission (almost always on paper) or closed so only a few companies could submit or special circumstances only one company.
A company or designer could make an unsolicited proposal if they thought they had something really good but in the 1930s no country had unlimited money to spend on prototypes.
Contracts were a lot easier to manage in peacetime when quantities were in the hundreds (if not lower) than war time in the thousands. Wartime also got into government owned but privately managed plants with the government owning the land, buildings and machinery so how much should it cost to produce that single engine fighter in that plant compared to the same fighter being built in private plant that needs to pay property taxes, bank loans/investors for building/machinery and other higher fixed costs.

I would note that any air ministry worth the roof over their heads tried to take into account factory size, experience ( don't give contract for 4 engine bomber to company that had only built single engine aircraft?) and the demand for certain engines when evaluating proposals. For instance in Germany in 1937-38 just about every designer wanted to use DB 600-1 engines, there weren't enough to go around even with new production facilities being built so a design that used an alternative engine might be view with favor.

 

[michael rauls]

I don't know about other countries and even US procurement changed from before the war to during the war.

But in general an air force (army or navy or independent) put out a requirement for a new type of aircraft. It could be an open competition with any company being able to make a submission (almost always on paper) or closed so only a few companies could submit or special circumstances only one company.
A company or designer could make an unsolicited proposal if they thought they had something really good but in the 1930s no country had unlimited money to spend on prototypes.
Contracts were a lot easier to manage in peacetime when quantities were in the hundreds (if not lower) than war time in the thousands. Wartime also got into government owned but privately managed plants with the government owning the land, buildings and machinery so how much should it cost to produce that single engine fighter in that plant compared to the same fighter being built in private plant that needs to pay property taxes, bank loans/investors for building/machinery and other higher fixed costs.

I would note that any air ministry worth the roof over their heads tried to take into account factory size, experience ( don't give contract for 4 engine bomber to company that had only built single engine aircraft?) and the demand for certain engines when evaluating proposals. For instance in Germany in 1937-38 just about every designer wanted to use DB 600-1 engines, there weren't enough to go around even with new production facilities being built so a design that used an alternative engine might be view with favor.

Verry informative thanks. It just sounded like the processes you described with the p40 was rather cumbersome. Specifying a preferred engine that didn't work out for example rather than put the requirements out there and let the manufacturers come up with there best design/ modification and then accept the best proposals.

 

[Venturi]

Probably the most innovative Curtiss aircraft, which was never contracted for in decent numbers, was the Demon

As has been exhaustively stated already, Curtiss put a tremendous effort into trying to upgrade the P-40. Actually more than they should have BUT contracts kept coming in for the P-40 and as long as Governments were wanting it, Curtiss was going to build it.


So did every other aircraft manufacturer.
Grumman's F4F was used through to the end of the war. GM even continued to manufacture it until 1945, two years after Grumman stopped manufacturing it.
And the Wildcat was older than the P-40.



Wait, What?
The few Army P-26s at Pearl Harbor were caught on the ground and destroyed, only the P-36 and P-40 were able to engage IJN elements.
The USAAC P-26s in the Philippines were also caught on the ground. Only some Philippine Army P-26 aircraft, flown by Philippine pilots engaged the Japanese.
The bulk of USAAC fighter groups were already equipped with the P-40 and were in the process of phasing out the P-36 when the U.S. entered the war in December 1941.

This is not the order of battle as "Bloody Shambles" by Shores relates it...

 

[Shortround6]

Verry informative thanks. It just sounded like the processes you described with the p40 was rather cumbersome. Specifying a preferred engine that didn't work out for example rather than put the requirements out there and let the manufacturers come up with there best design/ modification and then accept the best proposals.

To me the XP-53/XP-60 saga kind of shows where the P-40 improvement got derailed. Either the army (or Curtiss) wanted a plane to compete with the P-47 with it's eight .50 cal guns, so the XP-53/60 got stuck with a laminar flow wing (+) about 1/2 way (275 sq ft) between the P-40 and the P-47 (-). Bigger, heavier wing means bigger heavier airplane and you really need a bigger heavier engine to power it. One of the XP-60 prototypes got a Merlin engine of the type used in the P-40F and despite weighing hundreds of pounds more than a P-40F and having that extra 40 sq ft of wing area was actually a bit faster while the test notes claim the engine wasn't making full rated power ????

Hmmmm, instead of building a 80-90% new airplane (they did some parts from the P-40 fuselage) design a smaller wing that only holds six guns for the P-40 using the same airfoil???
You get something closer to the Mustang, you get it sooner, it just isn't quite as mean and nasty as the army was looking for (but then most of the mean and nasty planes the Army wanted never made it to production.)

 

[GrauGeist]

This is not the order of battle as "Bloody Shambles" by Shores relates it...

Order of Battle for Pearl Harbor or the fall of the Philippines?

I'm still fascinated to know more about all these P-26s battling the A6M other than the few in China and the several out of 28 in the Philippines that survived the initial attacks.

 

[davparlr]

I agree with a lot of that but the B-26 is a mixed bag.
The short wing B-26 was usually being operated thousands of pounds lighter than the later big/tilted wing planes. This would usually mean less bomb load or range or both had they kept building the short wing planes.

See; http://www.wwiiaircraftperformance.org/B-26/B-26_Operation_and_Flight_Instructions.pdf

The B-26 went from an under 30,000lb aircraft to a max 37,000lb aircraft. Maybe 1500lb can be attributed to the bigger wing, tail, armor and increased armament?

 

[davparlr]

I agree with a lot of that but the B-26 is a mixed bag.
The short wing B-26 was usually being operated thousands of pounds lighter than the later big/tilted wing planes. This would usually mean less bomb load or range or both had they kept building the short wing planes.

The B-26 went from an under 30,000lb aircraft to a max 37,000lb aircraft. Maybe 1500lb can be attributed to the bigger wing, tail, armor and increased armament?

I'm not so sure. Velocity, which is a squared term, is a much more powerful lift variable than wing area, which is a linear function. If we hypothetically take a B-26Bs and calculate the amount of lift at 214 mph (the cruise speed of a long wing B-26C) and then calculate the lift of that very B-26 at 260 mph (cruise speed of the B-26B short wing) I think we will find that the high speed B-26 generates almost 50 percent more lift than the slower airspeed B-26. Now if we do the same for the increased wing area, I think we would find that the big wing B-26 would only generate about 10% more lift than the short wing B-26 at the same airspeed. Now the max gross weight of the B-26B long wing is about 4000 lbs more than the max gross weight of the short wing B-26B of which about 1500 lbs is the weight of the new wing, which the short wing doesn't need. So, if we add 7 percent more weight to the short wing B-26, which from the previous example, should be easily accommodated, we will increase induced drag. But, because induced drag reduces with velocity, weight increases tend to have little effect on high speed flight therefore cruising speed may have to reduce only a small bit. So, in my opinion and rough calculations, if they are correct, I think the short wing B-26, which has less drag, could have been faster, flown farther, and carried more bombs than the long wing B-26. The drawback- the AAF would have to have longer airfields to accommodate a higher takeoff speed, which would certainly have been cheaper than putting longer wings on the B-26. It is interesting to note that the cruising speed of the short wing B-26 is only 22 mph slower than the top speed of the long wing B-26. That was a lot of performance to give up. It was the short wing B-26s that attacked the Japanese at Midway and of who commented that they were blazingly fast and difficult to bring down.

Most of this data comes from Ray Wagner's American Combat Planes and Charles Mendenhall's Deadly Duo. The rest from my possibly hair brained calculations.

 

[Shortround6]

Some other things were going on between the early short wings and the later aircraft. The early ones had spinners on the props, the air intakes were smaller (no sand filters) the oil cooler intake at the bottom of the cowl was smaller, the tail gun position may have had less drag (when closed)

From the pilots manual the speeds of 326mph or 323mph were obtained at 26,734lbs.
However the weight chart shows a normal gross weight of 28,706lbs.
This Normal gross is for 465 gallons of fuel and 2086lb of bombs.
Armament is one .30 cal in the nose, one .30 cal in the tunnel, the two .50 cal in the top turret and a single .50 in the tail. Each .50 has 200 rounds. The .30s have 600 rounds each. There is only a 5 man crew. Turret gunner mans the tunnel gun?

The speed figures are either for bombs gone or only about 130 gallons of fuel left in the tanks.

A short wing with the twin .50s in the tail, one or more .50s in the waist/bottom positions, and a .50 in the nose is going to pick a fair amount of weight (forget the cheek guns that come later) and that is part of the 1500lb increase, not just the weight of the bigger wing.
Carrying more than four 500lb bombs is going to affect things. and it could easily carry more.
filling (or trying to run) with fuel in the outer wing tanks is going to add weight.

The Big wing gets a lot of blame but the 323mph figure and the cruise speeds that go with it were obtained at a weight that was thousands of pounds below the way the plane wound up being operated.
The early planes were a bit sensitive to weight distribution. With bombs and ammo gone and less than 250 gallons in the tanks ( it took off with only 465 gal) it was recommended in the manual for two of the crew members from the pilots and/or navigator stations to move to seats in the turret compartment to help get the CG in trim for ease of control when landing. maybe increasing the weight of the rear guns solved that?