P-40 Warhawk/Kittyhawk

Ad: This forum contains affiliate links to products on Amazon and eBay. More information in Terms and rules

... I'm going to assume you're being funny here, because if you actually missed the "your base assumption is" part preceding that, then you make me sadface, sir.
Not THAT funny, I don't recall Jesus ever flying a P-40 but you might want to consider that line of response could well be offensive to any number of members on here.

I've seen that comparison made before- I know precisely where you're coming from - but I'm not so sure it's an accurate one. Simply put, I don't know if it's fair to regulate the P-40 to the same era of out-dated aircraft that the Hurricane belonged to. I personally think the P-40 had more potential then it was given credit for.
Whether it's fair or otherwise, the P-40 belonged to the same mid-30s-designed range of fighters that the Hurricane belonged to. You will need to spell out exactly why you think the P-40 had more potential that it was given credit for and it won't do you any good trotting out the 'fit it with a Merlin' argument again - we've already shown you that in the P-40F and L it didn't exactly light the plane up.

...because the P-51 came about as a direct result of the British trying to buy P-40s. As Wikipedia says:

Originally Posted by Wikipedia
North American Aviation (NAA) was already supplying their Harvard trainer to the RAF, but were otherwise underutilized. NAA President "Dutch" Kindelberger approached Self to sell a new medium bomber, the B-25 Mitchell. Instead, Self asked if NAA could manufacture the Tomahawk under license from Curtiss.Kindelberger replied that NAA could have a better aircraft with the same engine in the air in less time than it would take to set up a production line for the P-40.
But don't you see why that damns your argument? Why did Kindleberger suggest something better (that didn't even exist yet!) if the P-40 had so much development potential left in it?

Earlier in the article it says that the only American aircraft that came close to what the RAF purchasing commission required was the P-40. I'd wager that a good range was part of that requirement.
I'd wager the other part was the lack of anything else to choose from; you can come close just by being the best of a bad bunch...

I just think that the P-40 had much potential then most people give it credit for, and the reason it wasn't fully realized is that the American war machine was going all out- current fighters were being built and upgraded even as several new designs were being built. America had more resources available in terms of production lines and such then Germany, or England. If Germany had had the resources, they would have thrown all their resources into building FW-190s and 190Ds instead of continuing to upgrade the Bf109, but it was easier to upgrade a proven design then work out the kinks in an entirely new one.
We've yet to nail this elusive potential of yours...
I don't really see anything that provides any new clarity in the rest of the piece in fact, I'd say it rambles a bit

The P-40Q, as others have just pointed out, was an attempt to make the P-40 into a clone of the P-51, which it would never, ever be. The P-40 just didn't have it in it to be a high-altitude high speed fighter. However, simply adding a decently powerful powerplant to an already proven design would have improved it's usefulness drastically for very little invested in R&D costs- and time, always a crucial factor when you need every fighter at the front right away. After all, the Curtiss factory was going all-out even as the P-51 was entering production. Now, the P-39D2, in 1941, had a 1600 horsepower Allison V-1710-63 engine in it, a massive improvement over the 1100 horsepower Allison it had before. The P-40E of the same era only had the Allison V-1710-39, with an anemic 1150HP. Why couldn't they get the Allison -63 into the P40? Does anybody know the reason?
I don't think anyone pointed that out.
The XP-40Q had a -121 Allison with two-speed supercharging and water injection good for around 1430hp - I'd call that a decently powerful powerplant. I'm not really sure what the rest of this piece is trying to tell me either.

Dude. The Fw190, with its radial engine, was a poorer high-altitude performer than the Bf109. And yet, the 190 was preferred because most dogfights took place below 15,000 feet, where the 190 was superior
At the time of the Fw190's introduction to the ETO it was pasting Spitfire Vs left, right and centre. The RAF was getting kicked in the teeth. It wasn't until the introduction of the Spitfire IX that they had a hope of engaging the Fw190 on something like level terms, or not, if they chose to remain at altitude. The 190, unlike the P-40, was able to develop into something that could redress the balance and kept developing until the end of the war. This is the train that you keep missing, development potential - the P-40 didn't have alot of it

And consider that Luftwaffe pilots found that the Mustangs performance advantages were only at altitude, and that they disappeared the closer to the ground you got
That's still not a good enough reason to keep the P-40

But that doesn't mean for one second that the energy fighter (in this case, the P-51) could dominate the fight. The Mustang could be a thousand yards away before the P-40 could turn to face him, but that also means that the P-40 will always have plenty of time to get his nose on target with the P-51 for the next pass. In this case, the fight degenerates into a series of head-on passes, and that's not good. You've got a 50/50 chance of coming out on top, even if you have better guns- and that's just a wash.
Fighter comparisons are usually made with all things being equal eg both at same altitude, both at their optimal cruising speed, both pilots see each other at the same time etc etc. The P-51 could be a thousand yards away before... yes and by that standard of comparison the P-40 could be tucked underneath the P-51 in his blind spot and gun him down before the P-51 knew what hit him. There are countless instances where a P-40 could shoot down a P-51 but my money's still on the P-51.

But gee, I thought you said that the P-51 was never originally designed to be a long-range escort fighter! But it had the potential to grow into a long-range fighter, and the 190 didn't. Therefore, by your logic, both the 109 and 190 were obsolete.
That wasn't my logic at all (and alot of your argument seems to centre around this technique; I have to search my previous posts trying to figure out which of my responses you are countering). I did say that and I maintain that argument, it wasn't originally designed for that. But here comes that term again development potential - the P-51 evolved into the role. Pure interceptors on the other hand are simply the smallest possible airframe wrapped around the biggest possible engine, not alot of room for internal, range-extending fuel.
Neither the 109 nor the 190 series were obsolete and continued to be a headache for Allied escort pilots up until the end of the war.
 
I guess this would depend on how much different the A-model mustangs were from the D-models that went into Germany.
There you are, some homework for you

Let me guess, unless I can dig up extensive technical documents or pilot accounts comparing the durability of the P-40 to the P-51, you're going to cry foul?
This is the corner you've fought yourself into; yes, I would like to see at least some documentation that supports this.

Are you really going to argue that the P-51 was a better low-altitude fighter then the P-40? When the P-40 could out-turn and out-roll the P-51, and the P-51's speed advantage was slimmest on the deck?

In any case, I find it very interesting that the P-51 actually was deployed as a purpose-built fighter bomber- the A-36! It was used in North Africa, and was basically a P-51B with dive brakes. By all accounts, they fared quite well. This demonstrates, I think, that the P-51 wasn't a bad low-altitude fighter- it's just that the Pony does a lot better at altitude. On the deck it's equal, at 30,000 feet it shines.
No, I'm not arguing anything, you are arguing that the P-40 was a better multi-role (better than what, you don't say) fighter. You still haven't presented a case for the P-40 multi-role supremo

Yes, I eagerly await the rest of the forum telling me how an excellent power to weight ratio is not tremendously useful.
Excellent power to weight ratio? Presumably this explains the P-40's less than sparkling climb rate? However, you did, as ever, respond to a point I wasn't making, that of the Bf109 being inferior in every respect; I'm sure there more learned Bf109 students than I on here who will tell you exactly what a Bf109F would make of a P-40

It wasn't the cleanest ship, not by a long shot- but it WAS a superior energy fighter to the Zero, only because the Zero was a very dirty ship with that big radial, and was so very light. Against pretty much every other fighter of the war, the P-40 was a furballer- slow, but manuverable. The Zero is the only exception, because the Zero was right on the extreme end of the scale.
Wrong way around, the P-40 was pretty dirty, I don't believe the A6M could be described as very dirty. The rest of the piece is back in ramble mode I'm afraid, I'm not sure what you're trying to say
 
Colin1 said:
Not THAT funny, I don't recall Jesus ever flying a P-40 but you might want to consider that line of response could well be offensive to any number of members on here.
Click to expand...

Yes, in the same breath that I mention Optimus Prime- thus establishing that I am referencing both as examples of supreme, unassailable power? Yes, what a shattering insult to the Christian faith, of which I am a member. I expect adults- especially the people I have been privileged to speak with on this forum- to be rational enough to understand what is being said.


Listen very carefully, because I am tired of repeating myself.

  • The P-40 had an excellent turn rate, better then most fighters of the war.
  • The P-40 had an excellent roll rate, better then most fighters of the war.
  • The P-40 was a very durabe fighter, able to absorb much damage.
  • The P-40's performance suffered only because of insufficient engine power, which was easy to remedy with a more powerful powerplant.
  • In short, the only aspect of the P-40s performance that was lacking was the powerplant. With the addition of a more powerful engine, the otherwise-excellent performance characteristics of the P-40 would have kept it a competetive fighter.

But don't you see why that damns your argument? Why did Kindleberger suggest something better (that didn't even exist yet!) if the P-40 had so much development potential left in it?
Click to expand...


Because people disagree. Just because Kindleberger said the P-40 was tapped out doesn't mean it was. A disagreement between the Army and the Navy over the B-36 bomber led to something called the "Admiral's Revolt."

Oh, and lets not forget that by building their own fighter, North American Aviation wouldn't have to pay a licensing fee to Curtiss-Wright for each fighter built.

I'd wager the other part was the lack of anything else to choose from; you can come close just by being the best of a bad bunch...
Click to expand...

It was, in fact.

We've yet to nail this elusive potential of yours...
Click to expand...


It's only drawback was a weak engine. There. Put a better engine in it, you have a much better fighter. That's it.

The XP-40Q had a -121 Allison with two-speed supercharging and water injection good for around 1430hp - I'd call that a decently powerful powerplant. I'm not really sure what the rest of this piece is trying to tell me either.
Click to expand...


That engine was needed in the production P-40s to improve their performance, not in some ill-conceived "P-51 clone."

This is the train that you keep missing, development potential - the P-40 didn't have alot of it
Click to expand...

Prove it. Even the late Merlin-engined models received only 1200hp engines, not the 1500 hp ones they needed. You can't dismiss the P-40s potential simply because nobody actually used it.

That's still not a good enough reason to keep the P-40
Click to expand...

The P-40 was tougher, more manuverable, and cheaper. Good enough?

There are countless instances where a P-40 could shoot down a P-51 but my money's still on the P-51.
Click to expand...

You fail to understand the scenario that I am describing. Assuming a "fair fight," i.e, both aircraft head-to-head and spot each other at a good distance, the P-51 will not turn in a circle to fight the P-40, but will fly a distance off and turn around to make another pass, by which time the P-40 will be turned around to face it. It will be a series of head-on passes if the P-51 chooses to energy fight.

Colin1 said:
This is the corner you've fought yourself into; yes, I would like to see at least some documentation that supports this.
Click to expand...

Cool, show me some documentation that proves that the P-40s development potential was used up.

Colin1 said:
Excellent power to weight ratio? Presumably this explains the P-40's less than sparkling climb rate?
Click to expand...

You seem to have trouble with basic reading comprehension. I was talking about fighters that DID have good power-to-weight ratio, not the P-40. How could you make this error when I've spent the entire thread talking about how badly the P-40 needed a more powerful engine!?

Colin1 said:
No, I'm not arguing anything, you are arguing that the P-40 was a better multi-role (better than what, you don't say) fighter. You still haven't presented a case for the P-40 multi-role supremo
Click to expand...

Mostly because the P-40 was more durable and was a better gun platform (the P-51 was notoriously twitchy on the controls.) It was a better gun platform because the sturdier wings didn't flex as much, though I don't know if this advantage was marked.

The success of the A-36 as a dive-bomber shows that the P-51 was just fine at jabo, however. I'm not saying the P-40 was "supreme" at multi-role, but there were some reasons to favor it in theaters where ground attack was borne by fighter-bombers instead of high-altitude bombers that required escort.

Colin1 said:
However, you did, as ever, respond to a point I wasn't making, that of the Bf109 being inferior in every respect; I'm sure there more learned Bf109 students than I on here who will tell you exactly what a Bf109F would make of a P-40
Click to expand...

The P-40 had a superior turn and roll rate. The Bf-109 had much better power to weight ratio. I can tell you exactly what a P-40 would make of a 109. It'd save it's airspeed to put it's nose on target if the 109 tried to climb and attack from a dive; dive to the deck to make such attacks more difficult (the ground precludes a diving escape afterward, forcing either a more vulnerable zoom climb or a transition to a slower, more horizontal approach,) and then attempt to force a scissors or turn fight, where the P-40 is dominant. Alternately, the 109 pilot might insist on a series of head-on passes, in which case the victory is down to luck, nerve, and who is the better shot.
 

Can you step away from your strong affection for the P-40 and think through all the classic comparisons of ACM metrics (WL, Power to Weight Ratio, Roll Rate, Power profile of the Engines) and still make a case that the P-40 was as good as either the Me 109 or Fw 190 or P-51B?
 
Yes, what a shattering insult to the Christian faith, of which I am a member. I expect adults- especially the people I have been privileged to speak with on this forum- to be rational enough to understand what is being said.
Your arrogance will be your undoing my friend, just because you don't find something offensive doesn't mean others won't. It's precisely because they're adults that you don't need to resort to overblown superlatives normally expected from a teenager

The P-40 had an excellent turn rate, better then most fighters of the war.
The P-40 had an excellent roll rate, better then most fighters of the war.
The P-40 was a very durable fighter, able to absorb much damage.
Yes it did, when did anyone say that it didn't?

The P-40's performance suffered only because of insufficient engine power, which was easy to remedy with a more powerful powerplant.
In short, the only aspect of the P-40s performance that was lacking was the powerplant. With the addition of a more powerful engine, the otherwise-excellent performance characteristics of the P-40 would have kept it a competitive fighter.
There was more to the P-40's lack of power than the engine, it was a dirty airframe and that's where it was out of favour with newer designs. These were complementing the better powerplants with cleaner designs and more efficient methods for dealing with losses around the airframe. That's why the Packard Merlin in the P-40F only made a difference over previous versions of the P-40; stacked up against similarly-engined but newer designs, it wasn't competing.

That engine was needed in the production P-40s to improve their performance, not in some ill-conceived "P-51 clone."
So if the 1500hp Packard wasn't doing it for the P-40, why do you think the 1430hp Allison would have?

Prove it
History

Even the late Merlin-engined models received only 1200hp engines, not the 1500 hp ones they needed.
Packard Merlins were not 1200hp

You can't dismiss the P-40s potential simply because nobody actually used it.
It was used, they wrung as much as they could get from the P-40 airframe and then they moved on.

The P-40 was tougher, more manuverable, and cheaper. Good enough?
No. It wasn't fast enough and couldn't climb well enough; it was turning into a boom and zoom victim for the newer fighters. Cheapness is what mainly kept it in production for so long after its obsolesence.

You fail to understand the scenario that I am describing. Assuming a "fair fight," i.e, both aircraft head-to-head and spot each other at a good distance, the P-51 will not turn in a circle to fight the P-40, but will fly a distance off and turn around to make another pass, by which time the P-40 will be turned around to face it. It will be a series of head-on passes if the P-51 chooses to energy fight.
Oh, I think I understand you; isn't that what Japanese fighters tried to do when the late-war USN fighters came scything through them?

Cool, show me some documentation that proves that the P-40s development potential was used up.
There's one set called NA-73

You seem to have trouble with basic reading comprehension. I was talking about fighters that DID have good power-to-weight ratio, not the P-40. How could you make this error when I've spent the entire thread talking about how badly the P-40 needed a more powerful engine!?
and you seem to have trouble with professional courtesy and manners when presented with an opinion counter to your own. You gave a very strong impression that you were referring to the P-40 when you said that

Mostly because the P-40 was more durable and was a better gun platform (the P-51 was notoriously twitchy on the controls.) It was a better gun platform because the sturdier wings didn't flex as much
Do you know this from your days on flight sims?

I'm not saying the P-40 was "supreme" at multi-role, but there were some reasons to favor it in theaters where ground attack was borne by fighter-bombers instead of high-altitude bombers that required escort
Actually you did, but ground attack, down low, would favour the P-40; let's leave it there and pretend you never said multi-role...
 

Perhaps I'm not making myself clear. I have said- multiple times- that the P-40 was nigh crippled by it's very poor power-to-weight ratio. It had excellent performance in other categories- the airframe was inherently very manuverable- but without a proper engine, it's absolute disability in the vertical allowed aircraft like the Bf-109 to simply extend away, loop over the top, and make diving attacks from above with near impunity.

Now, in 1940, the P-40 was pretty evenly matched with the 109, having superiority in manuverability but inferiority in power-weight ratio. For reference, the A-81 A-2 Hawk had a power-to-weight ratio of 0.31 (Horsepower/Kg.) The Emil Meschersmitt had one of 0.45. By the time the Me-109 Gustav came out, however, the discrepancy in power-weight between the two ships had gone from significant to dominant. By 1942 the Gustav was sporting a 1400 hp engine, while the P-40s engine still labored around 1200hp, where it had been since 1940. (Engine upgrades in the P-40 seem to have improved high-altitude performance, but not actual raw power output on the deck.) This meant that the Gustav had a power/weight of 0.52 hp/kg while the P-40 stayed at 0.31. The discrepancy went from an edge for the Bf-109 to a dominant advantage that the Bf-109 could exploit at will.

A proper powerplant upgrade would have allowed the P-40 to counter the vertical advantage of later Bf-109s with some ability- by giving it enough power to reliably keep it's nose in the air long enough to meet a diving Bf-109 (or Fw-190, for that matter.) The necessity of meeting diving attacks by climbing to meet them was first observed by Boelcke in 1918. This wasn't as important in 1940, when the ability of the Bf-109 to get in such a position, as well as it's ability to extend far enough away to try it, wasn't as pronounced, but by the time the Gustav model came out, it was imperative.

This same analysis can be applied to both the P-51B and Fw-190. Even though neither of these aircraft were known to be great climbers, the P-40 was such a poor one that it really didn't matter.

I took some time to type up this explanation, so I'd appreciate it if you didn't dismiss it as my "affection for the P-40."

Now, on to Colin!

Colin said:
Your arrogance will be your undoing my friend, just because you don't find something offensive doesn't mean others won't. It's precisely because they're adults that you don't need to resort to overblown superlatives normally expected from a teenager
Click to expand...

It's called hyperbole, and it is a useful literary technique.


Agreed. The P-40 was not, and never would be, a high-speed energy fighter. The issue of the powerplant was simply that it required mediocre, adequate performance in speed and power-to-weight ratio, elsewise it's advantages could be neutralized handily.

Colin said:
Packard Merlins were not 1200hp
Click to expand...

Which models received 1500hp Merlins? Wikipedia says that even the late-model N production runs were still being fitted with Allisons. Did any other model besides the experimental Q prototype mount a Packard Merlin? I throw myself upon the greater knowledge of my fellows here, for I know not.

So if the 1500hp Packard wasn't doing it for the P-40, why do you think the 1430hp Allison would have?
Click to expand...

Who says the 1500hp Packard wasn't doing it for the P-40? Just because the P-40 so equipped wasn't as fast as the P-51? A P-40M Warhawk with a 1500hp engine would have had a power-weight ratio of 0.51 hp/kg. Or the 1400hp Allison, which would yield a ratio of 0.47, still much better. (I'm still curious as to why that Allison engine in the P-39 was never put in the P-40- technical difficulties, perhaps?) The Allison in the P-39 was most certainly available by 1942.

Colin said:
No. It wasn't fast enough and couldn't climb well enough; it was turning into a boom and zoom victim for the newer fighters.
Click to expand...

All which could have been greatly alleviated by a better powerplant. This is what I'm trying to say- all the reasons that you give for why the P-40 was lacking could have been addressed with a better powerplant. It wouldn't have eliminated them, but they would have been far less problematic.

Colin said:
Oh, I think I understand you; isn't that what Japanese fighters tried to do when the late-war USN fighters came scything through them?
Click to expand...

Scything? Not even a Hellcat driver was eager to pit his ship against the firepower of the Zero's 20mm cannons. No, the scything owed much more to other factors, not the least of which being the Zero's high vulnerability and the rapid attrition of trained Japanese aviators.

Ask any WWII pilot what attack he'd prefer- a head-on attack, or an angle where the enemy couldn't shoot back at him- and I think you'll get the latter reply every time.

Colin said:
There's one set called NA-73
Click to expand...

I addressed that already.

Colin said:
and you seem to have trouble with professional courtesy and manners when presented with an opinion counter to your own
Click to expand...

If I didn't want your opinion I'd hardly be discussing the matter with you! It's simply very frustrating to spend so much time and effort making these verbose and detailed posts, only to have my meaning inverted 180 degrees several times by accident.

Do you know this from your days on flight sims?
Click to expand...

While we're discussing politeness, we might say a few things about your condescending, high-handed attitude. I try not to read too much into these things- much is lost in translation in the textual medium, after all- but it's poor form to call me impolite and then use an insult yourself in the next breath.
 
Sorry for the double post ladies and gentlemen, but Colin requested proof of the P-40s structural strength, and I was able to find it for him:


The source is here:

The P-40 in Soviet Aviation

This confirms the claim of a five-spar wing, and the strength offered by it. Finding similar data to compare the P-40 to the P-51 might be difficult, but I'll see what I can find regarding the P-51 in mid-air collisions- or even wing diagrams showing the number of spars.

The best I can do for now is this: http://img155.imageshack.us/img155/7608/1222905782388.jpg

I think that diagram shows a two-spar wing, but I can't be sure. In any case, it makes a lovely desktop.
 
Demetrious said:
...ladies and gentlemen, but Colin requested proof of the P-40s structural strength, and I was able to find it for him
Click to expand...
It won't take much detective work for your ladies and gentlemen to realise that I made no such request. I do however, recall saying this:-

Colin1 said:
The P-40 was structurally a strong aircraft... ...it was a robust fighter in a whole inventory of robust fighters
Click to expand...
I don't require any such proof and neither I suspect, does anyone else.

Its structural strength wasn't enough to prevent the P-40 from being rendered obsolete.
 
Colin1 said:
It won't take much detective work for your ladies and gentlemen to realise that I made no such request.
Click to expand...

All anybody has to do is scroll up to see this:


Your reply, as per your standard practice, is the one in bold- specifically requesting documentation to support my comparison of durability.

In any case, the same article, in the footnotes, says that a one or two spar wing was the norm in those days. I think it's a safe assumption that the P-40 paid for the extra structural strength from three additional spars with equivalent weight.

drgondog: An apology is in order, I missed 9/10ths of your last post, because it was in a quote box. I didn't realize you'd replied in bold.


Thank you! So the D-model Mustang gained a lot of weight, but the cutting down of the fuselage behind the cockpit eliminated some weight in turn and improved the aerodynamics of the ship? I'd assume the D model was faster, but the B model, lighter (and probably the better climber,) and the A model, even more so.

drgondog said:
There is no reason, nor is there a body of data, to suggest that one coolant system was 'better' than the other.
Click to expand...

Agreed. A liquid cooled system is a liquid cooled system is a liquid cooled system. The only real difference is how much armor any given plane had installed around it.


What?

The P-40 was one of the tightest-turning monoplane fighters of the entire war. It could do a 360 in 20 seconds, whereas most Bf-109 variants required 23. It could also outroll the Spitfire (at higher speeds,) easily outroll the Tempest, and the roll rate of the Zero was just hopeless (the Type 97 was a bit better.) The only ship that could really out-turn the P-40 was the Spitfire (I've seen numbers from 17-19 for the Spitfire.) I'll try to find a single chart that compares the P-40 and P-51 turn radius/rate (so don't be surprised if I edit.)

EDIT: Righto, I've found some data given by our fellows on this very forum in days past; attributed to Soviet testing:

Soviet Testing of the P-40. That seems to confirm my "19-20" second figure, at any rate. I'll see if I can find us data on the P-51s rate.

EDIT THE SECOND:


Source: World War II Aircraft Performance.

"Turn rate," is only one axis of manuverability. Roll rate is more important, since every aerobatic maneuver starts with a roll. For this reason I'd rate the Fw-190 as superior in maneuverability, because even though the P-40 could out-turn it without much trouble, nothing, absolutely nothing, could touch the 190s roll rate.


Well, pretty much everything I've read gives the P-51 24 seconds to make a 360 degree turn- but I'll say now that that usually doesn't tell the whole story, since there are so many other factors effecting turn rate.

What is this about "sustaining a level turn longer?" Planes don't just turn and turn until they fall out of the sky, they have a "sustained turn speed," at which the difference between induced drag by high AoA and engine power balance out. The sustained turn speed for the P-51 is most certainly higher then the P-40, for all the reasons you named- it's a cleaner ship with a bigger engine. Another consideration is that pure wing loading doesn't tell the whole story with the '51- the laminar flow wing made for less drag then another wing with the same wing loading, allowing the '51 to keep a higher energy state then another aircraft with the same wing loading- and thus make a faster turn.

However, that higher speed meant the turn radius would be larger, as well, so the P-40 would be able to turn inside the -51. This explains the phenomena nicely.

Colin said:
As to roll, the P-40 might out roll the 51 at low speed, What is your source to suggest the P-40's superior roll capability and if, cited, for which flight regimes?
Click to expand...

You're in luck, some nice people in another thread just showed me this: Roll rates. Observe how the P-40 is superior to the P-51 until about 280MPH, where they balance out. The Mustang is truly designed to work with speed.


Oh, simple. really. Since mV>>2 determines total energy, and the P-40 had more mass then the Zero, at the same airspeed, the P-40 had more energy stored in it then the Zero. This meant that it could bleed off more during violent maneuvers and still have some left to work with. Since both aircraft had about the same wing area- and thus induced about as much drag at any given angle of attack- the P-40 held more energy simply because it entered the fight with more.

The superior power to weight ratio of the A6M, however, meant it could replace energy much faster. P-40 pilots had to make very sure they didn't bleed off too much energy with needless maneuvers, because replacing it without trading altitude would be hard.

Again, all the P-40s problems come calling right back to the power plant, don't they?
 
Demetrious said:
Again, all the P-40s problems come calling right back to the power plant, don't they?
Click to expand...

Actually the P40 had a few other problems.
Stability comes to mind, something they finally addressed with the N models by lengthening the fuselage.
They also required constant trimming, something that made them somewhat dangerous in the ground attack role, particularly for bombing, and something that kept the P40 pilot task overloaded in a dogfight.
Here's a quote from Wing Commander James Edwards who flew Kittyhawks in North Africa.


Also a quote about reliability of armament in desert P40's.

The landing gear was also 'relatively narrow' which did lead to some accidents. The 109 and Spitfire had the same fault, though for some reason the Spit never got a rep for ground accidents.
 
Demetrious said:
Originally Posted by Colin
As to roll, the P-40 might out roll the 51 at low speed, What is your source to suggest the P-40's superior roll capability and if, cited, for which flight regimes?
Click to expand...
Though irritating
it's one thing to suggest I submitted a post when people can check that I clearly didn't, it's quite another to doctor a post to make it look as if I posted it.

Your incoherent ramblings are beginning to cross the line of decent behaviour, kindly refrain from this in future.
 

Clive Cadwell, highest scoring Aussie ace and a pilot in the African theatre, had this to say:

The highest-scoring P-40 ace, Clive Caldwell (RAAF), who scored 22 of his 28.5 kills in the P-40, said the type had "almost no vices", although "it was a little difficult to control in terminal velocity".
Click to expand...

That seems to confirm that the P-40 was tricky in the dive, but (seems) to conflict on stability. Not that surprising, however- P-47 pilots transferring to the P-51 often complained about how twitchy and sensitive the controls were, when even the official evaluations of the P-51 praised it's exceptionally stable handling.

All in all I'm inclined to believe that the P-40 was on the unstable side, because the N-models weren't lengthened for giggles, after all. Clearly it was a difficult aircraft to exploit to it's fullest.

By all accounts the P-40 was a good gun platform (owing primarily to the strength of the wings, which didn't vibrate as much, and the weight of the aircraft,) but problems with inherent stability would counteract that. In any case it doesn't seem to be as good a jabo fighter, if only for the problems in a dive.

Another issue with it's ground attack ability is an anecdote I recall from God is My Copilot, where it was said that a dive angle of over 30 degrees was avoided, because the centerline mounted bomb might strike the prop as it separated.

Hmm, perhaps the P-51 and variants really were the better Jabo fighters!

Also a quote about reliability of armament in desert P40's.
Click to expand...

Was this a problem attributable to the P-40s design, or the M2 Brownings? Maintenance of machinery in a desert environment is notoriously difficult, since sand is so damaging and gets into everything. Designs that expose too many critical components don't help, however.


My apologies, sir. In trying to respond to both you and drgondog at the same time, I accidentally typed your name into those quote tags instead of drgondog. This is a typo, nothing more.

I can only assume that you thought that quote was the request for technical information I asserted you had requested. You were asking after comparative durability, not roll rate, of course, and you asked for that verification in this post (most recently.) You were well within your rights to request supporting data, I might add.
 

No D, they also reduce to aerodynamics. In ACM, stick forces for roll and turn are also important and differed quite a bit between various WWII ships. ALL airframe design is a study in performance trade-offs for the target mission but all things being equal you are better served with the cleaner airframe.
 
Fair enough
though I'm not sure what this 'sir' thing is all about...
I do recall the post, but it was some documentation from a general call for any documentation to support your notion in its entirety; what can you see that the 1940s powers-that-were couldn't see in the P-40? I'm reasonably well-versed in how the US thought fighters should be built
 
drgondog said:
Hard to say D - the spar design approach is a shear web with caps top and bottom. The 'taller' the spar, the more effective it is in taking out bending loads - but also heavier.
Click to expand...

Interesting. We'd probably need more detailed schematics to be sure.


All of them, actually...

drgondog said:
That being said D- are you 'engineering' in a 'no engineering zone'. While I agree with much of what you just said I am curious regarding how deep you want to go in the math?
Click to expand...

As far as you can take me! Some months ago I heard some people calling the P-51 a mediocre turner, and started investigating wing loading data. I suspected that wing loading was far from the only determinator of turn rate, and soon I was into drag coefficients. And then there was turn rate vs. turn radius to consider...

Suffice it to say I still don't understand the aerodynamic principles effecting turn performance nearly as well as I'd like to.


Assuming an equal playing field- that is, both aircraft at co-alt, and having had time to build to their maximum speed at the given altitude (which was pretty much the same for the Zero and the P-40 for much of the war,) the P-40 will have more initial kinetic energy simply because it has more mass.


Sustain the turn rate? I never suggested the P-40 could keep a sustained turn with a Zero, never (and if I did, I was telling lies.) The wing loading of a Zero is insanely low.

If the P-40 engages in turning manuever a) it loses velocity faster than the Zero, and b.) the only remaining manuever the P-40 may perform to re-generate system energy is to intially trade altitude (potential) energy by diving to regain velocity.
Click to expand...

Are you saying that the P-40, while having more initial energy, also bleeds it off faster in any given maneuver? Fast enough to negate it's advantage?

When I speak of energy fighting, I speak of maneuvers that take advantage of instantaneous turn rate, but not ones that continue long enough to continually sap energy. Simply put, I imagine a P-40 pulling a hard instantaneous turn to gain lead on a Zero for a shot, and yet still keep enough kinetic energy that it will be safely out of guns range by the time the Zero reverses to put it's nose on target.

drgondog said:
The Zero may outclimb, out accelerate, out turn the P-40 as ACM options. When the speed of the ships reduces below 300mph the Zero also out rolls the P-40.
Click to expand...

This chart from WWII aircraft performance has the Zero rolling significantly worse then the P-40 at all speeds, at 10,000 feet.

Your sources may vary, of course. I sadly haven't found any other roll comparison charts yet to compare with this one.

Agreed on the climb and accelerate parts, however. A P-40 pilot really has to be careful not to let a Zero boom and zoom them (thankfully they're not the best at that,) and use their roll rate to turn a defensive situation into an offensive one. That, and keep their speed up, with the exception of guns defense break turns.

drgondog said:
Hmmm. You just spent a couple of lines describing why the P-40 had energy to burn in violent manuevers
Click to expand...

drgondog said:
So which?
Click to expand...

The P-40 started a fight with a Zero with a superior cache of energy, but once that energy was gone, it was gone. This principle of course applies to all energy fighters and all energy fighting- no aircraft can accelerate fast enough to escape an enemy right on their six that they've foolishly slowed down to furball with- but in the P-40s case the underpowered engine made this rule an absolute. Where other fighters could burn off a little more energy and replace it with good acceleration, the P-40 simply could not.

EDIT:


I call everybody sir. It's polite.

I think the powers that be back in the 1940s could see plenty in the P-40- it was just that by the time they had proper engines available for the P-40, they also had brand-new fighters available as well. I certainly can't fault them for going the route they did; that's just the way history played out.
 
Its understandable that we tend to emphasise the fighter abilty of an aircraft. However its worth remembering that the P40 was a very capable GA aircraft able to carry a payload that at the time, few other aircraft could carry.

Yaks, Zero's, Ki43, Me109's Spitfires and Hurricanes couldn't match it.

For that alone it deserves bonus points.
 
I have seen pictures of P40's carrying 3 x 500lb bombs and even 6 x 250lb bombs but the most I have seen on the Hurricane was 2 x 250lb.
I believe the impact on range was greater on the Hurricane than on the P40 and often in the Far East the Hurricane carried one bomb under one wing and a drop tank on the other, the same with 4 x rockets on a wing.

Certainly could be wrong on this and any information welcome
 
Demetrious,

You aluded, in a post that appears on page 8 of this thread, that the V-1710-63 engine, used in the P-39D, made 1600HP.
Now, the P-39D2, in 1941, had a 1600 horsepower Allison V-1710-63 engine in it, a massive improvement over the 1100 horsepower Allison it had before.
Click to expand...
Actually, it made 1325HP @ 3000 RPM on take-off 1150HP @ the same RPM @ 11800 ft.
It seems that Curtiss skipped this particular version of that engine and went straight to the "-73", going on to mount the "-81" and finally, the "-99" versions of this engine in successive models of the P-40.
The "-73" differs from the "-39" in that there is no gun synchonizer installed and it has improved take-off ratings.
Performance for "-73" is as follows:
1150HP @ 3000RPM - take-off
1150HP @ 3000RPM @ 11800 ft.
The "-81" differed from the "-73" in the supercharger's gear ratio and and it was equipped with an automatic boost control.
Performance for the "-81" is as follows:
1200HP @ 3000RPM - take off
1125HP @ 3000RPM @ 14600 ft.
The "-99" differed from the "-81" due to an "engine regulator" (define that as you will. Sounds like a governer to me) and an automatic manifold pressure regulator.
Performance for the "-99" is as follows:
1200HP @ 3000RPM - take off
1125HP @ 3000RPM @ 15000 ft.

On page 9, you stated you were unaware that a 1200 HP Packard-Merlin engine was used.
Wikipedia says that even the late-model N production runs were still being fitted with Allisons. Did any other model besides the experimental Q prototype mount a Packard Merlin?
Click to expand...
The "F" and "L" versions of the P-40 both utilized the Packard-Merlin engine.
I understand the practice was halted due to engine manufacture needed for P-51 use.
Also, the Packard-Merlin used in those P-40's was the 20 ("XX") series engine, which only made about 1300HP.

Here's the link to the Allison engine info - ModDesig

Here's the link to the Packard-Merlin engine info - http://www.raafwarbirds.org.au/targetvraaf/p40_archive/pdfs/1650-1.pdf

Here's the link to the P-40 info - Perils P40 Archive Data


Ok, that was all.
Pardon the intrusion.





Elvis
 
You must log in or register to reply here.

Users who are viewing this thread

Total: 1 (members: 0, guests: 1)

Similar threads

Paper comparing the flight performance of the P-40E Warhawk and the A6M2 Zero
Replies
8
Views
2K
Ivan1GFP
I
Polish outfitting & positioning of their armed forces, 1935-39(40?)
2
Replies
29
Views
672
tomo pauk
How good a plane was the P-40, really?
23 24 25
Replies
493
Views
47K
Think Tanker
M
P-61 Performance
Replies
15
Views
2K
Snautzer01
French Army alternatives, 1935-40 (41?)
2 3 4
Replies
64
Views
4K
Admiral Beez
A