Maneuverability vs Speed

[SaparotRob]

The TBD was terrible. It was inferior to the Swordfish and the Albacore by every yard stick, and they were both biplanes.

The TBF / TBM was pretty good though.

Never said it wasn't terrible. Up to that point, however, it seemed to work. You fight with what you have. It would've been interesting had TF 16 and TF 17 been re-equipped with the TBF instead. The TBF wasn't on the carriers, though.
I am on record saying the Stringbag was a brilliant design. The Swordfish's obsolescence was one of first myths the Forum busted for me that I took as fact. I said "it wasn't a bi-plane" as how the USN might've viewed the Devastator.

 

[Reluctant Poster]

The IJN had issues with coordinating strikes and finding their targets. Extreme range was of dubious value when facing an opponent who has AW radar, that could detect shadowing recon aircraft, and mass the CAP to intercept the strikes that actually found the target. Also in the south Pacific, you have a fairly equal day/night cycle, so usable range was limited by available daylight.

They did a better job than the Americans did at coordinating strikes. The USN were never able to launch a coordinated strike from multiple carriers in 1942. And the japanse never got lost as badly as the Hornets air group did at Midway.

 

[Reluctant Poster]

From what I understand 93% loss was from that one strike, same as the 6 Betty's that all went down, lets get real, losing 25% of your A6M's, 52% of Vals and 50% of Kates is simply unsustainable in anyone's language,

And exactly what strike are you referring to? Not any IJN carrier strike that I am aware of in 1942.

 

[RCAFson]

They did a better job than the Americans did at coordinating strikes. The USN were never able to launch a coordinated strike from multiple carriers in 1942. And the japanse never got lost as badly as the Hornets air group did at Midway.

The IJN had two strikes go astray at Coral Sea (one mistakenly directed to Neosho and Sims), and one at Eastern Solomons. Hornet's SBDs missed their targets but not the TBDs.

It also arguable that the strike against Midway (where USN AW radar allowed a retaliatory strike) and the plan for a 2nd strike was due to faulty recon.

In any event the longer range of the IJN aircraft did not seem to confer any advantage.

 

[Reluctant Poster]

Even the SBD made 138 claims - a number often challenged around here but I doubt that is more exaggerated than the 112 victories for the Fulmar.
Even the TBM / TBF made 98 claims.

I am the one who challenged the claims made by the SBD. It is not conjecture on my part, its a collation of the numbers presented by Lundstrom in his excellent First Team books. I will say the the massive overclaiming by the SBD is far greater than for any fighter. Note that most of the claims were made by the gunners and as a group they are notorious for overclaiming. Look at the claims made by B-17 in 1943. As an example in the first two weeks of October 1943 B-17s claimed 791 fighters shot down which was more than the frontline strength of the fighters defending the Germany. But I digress. For those how didn't read my previous posts here is the last one:

At Eastern Solomons the SBDs claimed 6 Vals but actually shot down 0.
At Santa Cruz they claimed 15! Zeros during the strike on the Japanese but actually shot down 0.
At Santa Cruz during the strike on the Americans they claimed:
2 Zeros actual 0
9 Vals actual 2
2 Kates actual 0

That's 34 claims vs 2 actual kills
As noted previously, up to and including Coral Sea SDBs claimed 31 EA vs 6 actuals

That gives a grand total of 8 actual kills vs 65 claims

I don't have data for SDB claims at Midway so it is not included.

The original posts are here:

Why the Skua Only Carried a 500lb Bomb

I debunked the SBD claims at Coral Sea previously: https://ww2aircraft.net/forum/threads/improved-skua-for-faa.52273/page-14#post-1751560 In another post I totaled the actual kills vs claims for the SBD at Eastern Solomons and Santa Cruz based on Lundstroms "The First Team and the Guadalcanal...

ww2aircraft.net

Improved Skua for FAA?

The prowess of the SBD as an ersatz fighter is greatly exaggerated. A large part of the SBDs claim to fame is the battle of Coral Sea. I was always puzzled by the extremely high USN claims for Zeros shot down during this battle. If these numbers were remotely true the Zero easily wins the title...

ww2aircraft.net

Improved Skua for FAA?

The prowess of the SBD as an ersatz fighter is greatly exaggerated. A large part of the SBDs claim to fame is the battle of Coral Sea. I was always puzzled by the extremely high USN claims for Zeros shot down during this battle. If these numbers were remotely true the Zero easily wins the title...

ww2aircraft.net

The 65 claims I found information on represent more than 1/2 of the claims made by carrier SBDs. Unfortunately I don't have any information on the 22 Zeros claimed made by Marine SBDs on Guadalcanal

 

[BarnOwlLover]

Biggest problem is that fighter pilots always want more of everything. They're like racecar drivers. Race drivers want more speed, more grip, better handling, more downforce, less drag, they want improvements in every area. Likewise fighter pilots. They want more speed, better climb, better dive, more range, more firepower, more agility, etc. But like with race cars, fighter planes come with few free lunches.

Planes like P-40s, P-51s, a lot of Spitfires, and even the Hawker Typhoon and Tempests were very agile--at medium to high speeds. Their weight and higher wing loadings wouldn't allow them to out-turn a Zero or Ki-43, let alone a biplane like a CR42 at low speeds. For that to happen, you'd basically need something like Fowler or Fairey-Youngman flaps to increase lift at low speeds. Also, relatively thin wings like what the Spitfire, Mustang and Tempest used weren't quite as good as thick wings at producing lift at lower speeds, either.

Again, we're sort of back at the "follow the bombers" mentality. And I'd also argue that we're also looking at the "horse for courses" train of thought as well. In the Pacific, the IJA and IJN did actually tend (and I've known this for a while) to use "boom and zoom" whenever possible. Of course, over China and initially against some other Allied aircraft, the IJA and IJN's fighters did have a speed advantage until stuff like the P-40 became common. One exception was when the Ki-27s encountered Soviet I-16s over Mongolia during those boarder skirmishes in 1939.

As far as the debate of armor and self sealing fuel tanks vs not having them. Common sense would suggest not having them is a big disadvantage. But most aircraft armor and SS tanks were only good a lot of times at stopping rifle caliber machine gun rounds and flak shrapnel. Granted, there were exceptions, especially later in the war where a lot of American and British fighters had SS tanks that could stop a lot of Japanese or German 20mm shells and .50 rounds comparable to their own (.50 BMG), same with armor at times. But in 1942, I'd question any fighter that was in widespread use in the first half of the year as having those abilities to be common place to stop heavier weapons. Not to mention with .50 and 20mm, those rounds could (at the time and earlier) do enough structural damage even with ball or AP ammo that armor or SS tanks didn't matter a ton, and the .50 and 20mm allied ammo (and Axis ammo) got better as the war went on, just as the armor and SS tanks did for Allied planes, and Axis planes where possible.

The latter also goes IMO for liquid cooled engines vs radial engines. Small caliber stuff, I'd say that some favor goes to the radial engine, HMG and cannon rounds, you're in reality probably just as screwed no matter what engine you're using at that point.

But in combat, you have to use what you have. PZL P7s and P11s did shoot down German aircraft over Poland in spite of being obsolete. Zero and Ki-43 pilots used their low speed agility to at least evade if not shoot down unwary Allied pilots in better aircraft. A lot of times, it's experience and tactics that make the difference. If you have two sides that are equipped about the same, the advantage will go to the side that has the better experience, tactics and strategy. If you have sides that have similar experience, tactics and strategy, then the advantage will go to the better equipped side. And of course, you're really screwed if your opponent has better equipment, experience, tactics and strategy.

That's not to say that they won't take losses, but that situation does make your job that much harder, especially if you're also outnumbered.

 

[RCAFson]

I am the one who challenged the claims made by the SBD. It is not conjecture on my part, its a collation of the numbers presented by Lundstrom in his excellent First Team books. I will say the the massive overclaiming by the SBD is far greater than for any fighter. Note that most of the claims were made by the gunners and as a group they are notorious for overclaiming. Look at the claims made by B-17 in 1943. As an example in the first two weeks of October 1943 B-17s claimed 791 fighters shot down which was more than the frontline strength of the fighters defending the Germany. But I digress. For those how didn't read my previous posts here is the last one:

At Eastern Solomons the SBDs claimed 6 Vals but actually shot down 0.
At Santa Cruz they claimed 15! Zeros during the strike on the Japanese but actually shot down 0.
At Santa Cruz during the strike on the Americans they claimed:
2 Zeros actual 0
9 Vals actual 2
2 Kates actual 0

That's 34 claims vs 2 actual kills
As noted previously, up to and including Coral Sea SDBs claimed 31 EA vs 6 actuals

That gives a grand total of 8 actual kills vs 65 claims

I don't have data for SDB claims at Midway so it is not included.

The original posts are here:

Why the Skua Only Carried a 500lb Bomb

I debunked the SBD claims at Coral Sea previously: https://ww2aircraft.net/forum/threads/improved-skua-for-faa.52273/page-14#post-1751560 In another post I totaled the actual kills vs claims for the SBD at Eastern Solomons and Santa Cruz based on Lundstroms "The First Team and the Guadalcanal...

ww2aircraft.net

Improved Skua for FAA?

The prowess of the SBD as an ersatz fighter is greatly exaggerated. A large part of the SBDs claim to fame is the battle of Coral Sea. I was always puzzled by the extremely high USN claims for Zeros shot down during this battle. If these numbers were remotely true the Zero easily wins the title...

ww2aircraft.net

Improved Skua for FAA?

The prowess of the SBD as an ersatz fighter is greatly exaggerated. A large part of the SBDs claim to fame is the battle of Coral Sea. I was always puzzled by the extremely high USN claims for Zeros shot down during this battle. If these numbers were remotely true the Zero easily wins the title...

ww2aircraft.net

The 65 claims I found information on represent more than 1/2 of the claims made by carrier SBDs. Unfortunately I don't have any information on the 22 Zeros claimed made by Marine SBDs on Guadalcanal

Additionally, Fulmar and Skua kill claims have been compared to Luftwaffe and RAI action and loss reports and most of the claims were confirmed. The Skua shot down more Axis aircraft in 1940 (~20) than the SBD did in 1942. Total Fulmar kills seem to be in the ~100 range.

 

[Shortround6]

On the speed is better side
P-51 over FW 190
Bf 109 over LaGG-3, I-16, early Yak 1 etc. [early Russian Front]
Bf 109 over Hurricane & early P-40 [BoB, North Africa]
P-38 and F4U and Hellcat over A6M and Ki-43 [South Pacific]
P-40 over Ki-43 [China / Burma]
Fw 190 over Spit V [English Channel]
Bf 109F over Spit V and Hurricane II [English Channel, North Africa]

Insufficient data.
No variant information, no speeds and no altitudes.

 

[Thumpalumpacus]

Ah, maybe as a way to distract / misdirect the German fighters?

A solid overview of the raid from inception to counting losses.

 

[Wild_Bill_Kelso]

On the speed is better side
P-51 over FW 190
Bf 109 over LaGG-3, I-16, early Yak 1 etc. [early Russian Front]
Bf 109 over Hurricane & early P-40 [BoB, North Africa]
P-38 and F4U and Hellcat over A6M and Ki-43 [South Pacific]
P-40 over Ki-43 [China / Burma]
Fw 190 over Spit V [English Channel]
Bf 109F over Spit V and Hurricane II [English Channel, North Africa]

Insufficient data.
No variant information, no speeds and no altitudes.

Not needed. Most people reading this forum, yourself included, know enough about all of these matchups, in the operational history, to verify that the plane in the left column had an advantage in outcomes over the plane in the right column.

Or are you suggesting that a P-51 wasn't faster than a Fw 190 or that a Fw 190 wasn't faster than a Spit V?

 

[Thumpalumpacus]

I'm sure it was a factor. But I think these numbers help make clear, it was not as much of a factor as is sometimes portrayed. It's not like the Zeros were made of matches and kindling wood while the Wildcats were flying bar-bells.

The A6Ms were much more agile and had better performance. And 20mm cannons. The F4Fs were tougher and had more ammunition, and probably more radios. It more or less equaled out, but this was later in the year (Santa Cruz was in Oct 1942), once the Americans had improved their tactics. In early 1942 the outcomes were much more in favor of the Japanese (against both US and British / Commonwealth forces).

I personally think pilot experience has a lot to do with this. Early in the Pacific war, American pilots weren't so canny, but by October they had more savvy.

 

[SaparotRob]

I personally think pilot experience has a lot to do with this. Early in the Pacific war, American pilots weren't so canny, but by October they had more savvy.

and moxie.

 

[Thumpalumpacus]

and moxie.

I bet fighter pilots on both sides, or rather all sides, had balls. What that means without experience, that's for the reader to decide.

 

[SaparotRob]

Choose wisely.

 

[Wild_Bill_Kelso]

I personally think pilot experience has a lot to do with this. Early in the Pacific war, American pilots weren't so canny, but by October they had more savvy.

It was pilot experience, but it wasn't just that.

First, the planes which weren't doing well were fairly quickly phased out. The F2A, the TBD, and the Vought 'Vindicator' were all gone after the first few months of the year. So that helped.

For the Navy - it was the Thach Weave- that helped survival a great deal. Thach himself survived the war and made ace with six victory claims. I love the whole story of this technique because it speaks to what you might call the good side of the American system. Low ranking pilot, actively thinking about what his job is going to be and what he and his comrades were going to be going up against. He was skilled in theory and came up with a good plan. And his superiors let him try it and when they recognized that it was working, they sent him to train their fighter pilots to do it. It became navy policy. Brilliant. Same guy later came up with an effective method for protecting aircraft carriers from kamikaze attacks, (though it was not popular with destroyer crews!)

They also improved the guns during 1942. In the early war period, they had a lot of trouble with the .50 cal machine guns jamming on all the American fighters. They sorted that out to a large degree by the middle of the year. They also rolled out the faster firing .50 caliber machine guns some time toward the end of the 1942 IIRC. Sr6 can comment on that if he wants I think he knows the details..

The F4F-4, even though performance was degraded compared to the F4F-3, was better protected with proper self sealing tanks.

With the P-40s at Darwin, New Guinea, and later Guadalcanal, they initially had a big problem with performance, if the pilot was flying to the limit of 42" Hg on the throttle, which maxed them out at about 1,100 hp. That was not enough for a ~8,000 lb aircraft. By the mid year this was increased officially to 56" or 57" Hg, to as high as 60" Hg, with a power increase to about 1,550 hp at lower altitude. At that level of power the P-40 could easily outrun the A6M at low altitude. That made a big difference. Some pilots pushed it further than that unofficially (called 'overboosting') as far as 70", probably at significant peril to their engines.

Tactics solidified with pilots made firmly aware of the 'hit and run' doctrine. Over time this was refined to the point that they would actually dogfight Zeros by using nose-down turns like Low-Yo-Yo. They developed special 'escape maneuvers', usually an outside roll or some side-slip followed by a Split-S into a power dive, and a slight turn to the left. This enabled a lot of P-40 pilots to avoid being shot down.

In mid 1942 they got some P-40K, which were improved over the P-40E with better ammunition storage and an engine rated for higher power (for the 60" WEP) and military power was raised to 44.2" Hg for 1150 hp. Toward the end of 1942, they got some P-40Fs, which were stationed at Guadalcanal. These had two speed superchargers and could make 370 mph at 20,000 ft.

Late 1942 also saw the first of the P-38 units in Theater.

Finally, training was improving in the states and the USN, USMC, and USAAF were all sending experienced combat pilots back to the states to help with training. That definitely made a difference.


So I think it was a combination of improved training and 'savvy' with some technical improvements with the planes.

They also got more flying boats and reconnaissance aircraft. B-24s.

 

[Wild_Bill_Kelso]

I also think logistics in general improved a great deal for the Americans over 1942. More and better food started to arrive (at least in some places, Guadalcanal was sometimes cut off). Things like DDT and mosquito nets. Spare parts and consumables for the aircraft. Tools. Rain proof shelters. Bulldozers. Water purifiers. Those Marston Mats for the muddy airfields really cut down on accidents. Medicine and medical facilities with staff. All that meant fewer sick pilots, more aircraft being repaired more quickly. Fewer casualties from malaria and other tropical diseases. More planes flying.

During the same period, by contrast for the Japanese crews especially on the islands, a lot of this stuff didn't improve nearly as much.

They also got more and better anti-aircraft guns. PT boats and more flying boats and seaplanes for air rescue, liaison and scouting. They put radar on Guadalcanal in Sept 1942 which helped a lot for early warning and coordination of the Cactus Air Force.

 

[PAT303]

Wrong battle.
Interesting statistic. More SBDs were lost in action prior to Midway than TBDs.

I mean the war, both it and it's torpedo shouldn't have been in it.

 

[GregP]

The TBD was terrible. It was inferior to the Swordfish and the Albacore by every yard stick, and they were both biplanes.

The TBF / TBM was pretty good though.

The TBD was faster than the Swordfish and Albacore were, had a smaller bomb load, and wasn't employed very well by the U.S. Navy. So, it didn't "sink the Bismark" or have any notable victories. But, we also didn't employ the F2A Buffalo very well. The Finns did and managed to have a good experience with it.

Perhaps the Devastator was better than our experience with it indicated. But, we didn't give them to the Finns ...so it's hard to say.

It's a "what if" with no correct answer, and all the evidence points to you being generally correct.

 

[Just Schmidt]

A light weight structure doesn't necessarily mean an inherently weak one as far as I understand (i'm not an engineer) - but it means it forgoing any extraneous weight including using the thinnest gauge / lightest materials possible. That means it might be perfectly strong enough in terms of performing its intended flight regime. Where it might become an issue in a combat however, is in the amount of 'redundancy' built into the structure. That might be perfectly acceptable under ordinary flight - but clearly becomes more critical when a bullet or lump of shrapnel passes through a structural member or you're hoping to survive a crash-landing. It also means potential less 'reserve' of strength in terms of metal fatigue (little understood at the time) or if the airframe became over-stressed in hard manoeuvres. It also meant in many Japanese aircraft forgoing things like self-sealing tanks, armour and other items for crew comfort etc.

And that's an important design criteria if you want good performance - especially range and manoeuvrability - from your available engine power. The unarmoured ultra light-weight aluminium pilots seat from a Zero posted earlier in this thread epitomises the approach of certain Japanese designers

Mitsubishi G4M: Why Betty Bombed

Mitsubishi’s G4M bomber went by many names, but perhaps the most appropriate would have been “flaming coffin.”

www.historynet.com

In order to achieve the G4M's great range and performance, he [Kiro Honjo] was forced to equip it with the largest possible fuel tanks and to forego rubberized self-sealing protection for them. Nor did he provide armor for the crew. (His friend Horikoshi seems to have taken the technique to heart in designing the Zero.) The Betty's wet wings were its tanks, with fuel cells neatly defined by the main spar and a secondary spar forward of it, the ends sealed by solid wing ribs. There was no self-sealing mechanism, which would have required a 1¼-inch-thick soft rubber layer weighing about 660 pounds, either inside or outside the fuel tanks, substantially reducing the tanks' capacity.

After 663 Bettys had been manufactured (some 2,400 would ultimately be built), Mitsubishi began to fireproof the wings by applying a thick self-sealing layer on the outside of the lower wing skins. This maintained the internal fuel capacity but adversely affected the airplane's aerodynamics. The rubber mat shaved about 6 mph from the G4M's speed and reduced range by almost 200 miles. Had they tried putting a matching mat on the exterior top of the wing tanks as well, the airplane probably would never have gotten off the ground.

The final version of the Betty, the G4M4, had an entirely new laminar-flow wing with integrally self-sealing fuel tanks. The benefits of laminar flow were probably illusory on Bettys, since IJNAS aircraft of all types had paint jobs that ranged from beater-bad to junkyard special, peeling and flaking in a manner that would have tripped any incipient laminar airflow. For years it was assumed that the Japanese simply didn't know how to make good paint, but the reason was even more basic. Mitsubishi aircraft were delivered to combat units in natural metal and spray-painted with camouflage in the field…without the benefit of primer.

The Betty was the product of excellent engineering pushed to the limit and then slightly beyond, to meet requirements created not by aviators but by military bureaucrats. Those procurement officers were aware of the airplane's main flaw but chose to accept it, dooming many crews.

The number of combat reports regarding the comparative fragility of many Japanese aircraft is pretty much legion. So trope or not, evidence seems to point towards it being accurate, at least for many types

Mitsubishi A6M Zero - Wikipedia

en.wikipedia.org

Every possible weight-saving measure was incorporated into the design. Most of the aircraft was built of a new top-secret aluminium alloy developed by Sumitomo Metal Industries in 1936. Called "extra super duralumin" (ESD), it was lighter, stronger and more ductile than other alloys (e.g. 24S alloy) used at the time, but was prone to corrosive attack, which made it brittle. This detrimental effect was countered with an anti-corrosion coating applied after fabrication. No armour protection was provided for the pilot, engine or other critical points of the aircraft, and self-sealing fuel tanks, which were becoming common among other combatants, were not used. This made the Zero lighter, more maneuverable, and one of the longest-ranged single-engine fighters of World War II, which made it capable of searching out an enemy hundreds of kilometres away, bringing it to battle, then returning to its base or aircraft carrier. However, that tradeoff in weight and construction also made it prone to catching fire and exploding when struck by enemy fire.

With its low-wing cantilever monoplane layout, retractable, wide-set conventional landing gear and enclosed cockpit, the Zero was one of the most modern carrier-based aircraft in the world at the time of its introduction. It had a fairly high-lift, low-speed wing with very low wing loading. This, combined with its light weight, resulted in a very low stalling speed of well below 60 kn (110 km/h; 69 mph). This was the main reason for its phenomenal maneuverability, allowing it to out-turn any Allied fighter of the time. Early models were fitted with servo tabs on the ailerons after pilots complained that control forces became too heavy at speeds above 300 kilometres per hour (190 mph). They were discontinued on later models after it was found that the lightened control forces were causing pilots to overstress the wings during vigorous maneuvers.

To quote our own GregP from 2012:

"The chief culprit in its fragility was the use of .032" Aluminum skin where the western powers used .040" or even .050" or even heavier. When everything is intact, the Zero is as strong as any western fighter. Once it gets battle damage it gets fragile, and the lack of self-sealing tanks and armor add to the perception of fragility."

Thank you for taking the time to give a reasoned answer.

However, i do not see any substantial data on the structure of the G4M as either strong or weak. And while it is true that a light structure isn't of nessessity a bad thing, you seemed to list it among draw backs. certainly the Betty lacked protection, but i do not count self sealing tanks and armour as structural deficiensies.

I can't really say how large a percentage of Japanese designs were structurally light or even weak. Some certainly were, but like the preferrence for radial engines do not make the Ki-61 a radial engined fighter, so the light structure of, say, the Ki-43 does not make the structure of specifically the G4M lightweight. Saying that the probably wasis not a proof.

Another old horse being trotted out is how armour and self sealing tanks were sacrificed in the design of the A6M. Where the Zero stands out is the time it took, far too long, before these were added to the aircraft. While some aircraft were designed in the late 30'es with protective measures incorporated (some IJAF bombers amongst them), it was not as common that exclusion was a sacrifice or a revoluitionary departure from current design praxcis. Exactly when it was becoming common, in the design process, or retrofitted as afterthought, is of course open to argument.

I think it is a shame that we know comparatively little about Japanese (and other participants planes) that we do, compared to planes like the Spitfire or B-17. That is not only because of bias, but also the availabilty of sources and ability to read what exists in the original language. No, I still don't believe Google translate suffices. But it avails us nothing to extrapolate from what we do know to what we don't know. In the case of the G4M the fact that the damn thing ligtet up so easily, will remove badly shot up aircraft returning to base from the dataset out of proportion with better protected designs with which we can, provisionally, compare them.

i sometimes consider the A6M to be both the most underrated and the most overrated aircraft of ww2. As many media want to present everything as a sensasion, first the myth of its invincibility, and then the myth of its utter uselessnes, has to be debunked over and over. we've discussed it often in this forum. And then the discussion starts over, with much of the old threads being not ignored, but rather not read. When i attempt to read everything just of current threads before posting, I often end up not posting at all.

This is partly an effect of the internet. I can mention a new (at least to me) channel on Youtube called something like 'mysterious super plane'. Both the utter thrash it presents in the videos, and the insane speed with which it puts out new videos, points to it mostly being made by chat bots.

 

[Just Schmidt]

That is a good question and it may be very hard to answer. We can look at the empty weight of the aircraft and the size for some indications but not proof.

According to Francillon the G4M1 model 11 was 9500 kg empty, the G4M2 model 22 was 12,500kg empty as was the G4M3 model 34.

Maybe my math is off but the loaded weight of the G4M1 model 11 doesn't allow for the full rated capacity of the fuel, let alone oil and crew.

for a crappy comparison the B-25A was 8,129kg empty and the B-25C was 9,220kg empty but they had a smaller wing (about 15 shorter and 73% in size) and the fuselage was almost 10 ft shorter. We can try looking at engine weights and so on. US bomber strength varies quite a bit as some planes were allowed to decline as they got heavier with only local or critical parts strengthened

I was considering the wieght angle, but for starters I'm not sure what is included in empty weight. Surely turrets but not ammonition, but what about the guns? is that consistent between sourses and nations? I simply don't feel competent enough to do such equations with confidence, even if I had the data, which i do not.

My first attempt to make this answer failed when i closed the tab accidentally, and now i don't have the books. anyway suffice to say that in a reference work i fonund the G4M1 considerably lighter than your figures, about one tonne. In the same work I found the Wellington Ic at approximately the same weight, but we can be certain it wasn't the same person weighing them. While reference works can be generally reliable, sometimes wierd data appears, other are missing and sometimes there are simple typos. Anyway.

I do think that, if we want to compare, the Wellington is a good comparizon. It had a lightweight stucture that i have often seen judged (comparatively) strong, it had good range and can be considered large for a twin, I think it was designed somewhat earlier.

It also had turrets, and on approximately two thirds the powewr it made some 378 km/h compared to around 428 (from memory). For the power available, the Betty was slow compared to most other Japanese bombers. At least in the west, the Wellington is so much better documented than the Betty.