P-47N Thunderbolt vs. F4U-4 Corsair - Which was superior?

[wmaxt]

John has tried to quantify the data from 20+ aircraft into a model that can be compared. Jon has tried to keep it as accurate as possible. Many /most of us havs stuck to one or a few aircraft simply because we can't cover them all, Jon, has given us a starting point.

The point I found most interesting is how close the top 10/12 aircraft were (not including the P-47N which had limited contact with most of the top 12).

In his comparison the P-51 was 8th, add tactics, training, and numbers and it was very effective in the ETO, showing how much more beyond the chart there is to consider.

As for sims, I think you may be confusing the sim experiance to the accuracy of the sim model. no they aren't reality but as Jon pointed out sims can accurately quantify the performance envelope of any aircraft. On the other hand a creative pilot can expand that envelope from there.

wmaxt

[Jank]

This disagreement that has come up is nteresting. Reading back I see that it began when Mr. Goldberg said that the P-47D-25 would be a better match against the F4U-4 than the P-47N.

I for one am not convincved.

[JonJGoldberg]

Reply to Wmaxt >>>

Thanks for your continued support. I’m having a little trouble understanding your reference to the ‘47N in the 2nd paragraph though.

I’ve just had time to go through the accident reports you set me a while back; you should repost the link. Seriously eye opening; GRRRREAT stuff!! Maybe the Lighting wasn’t as expensive as I originally thought. I wish data like this was available for all aircraft in the tables; I’d work on figuring out how to include this info...

Reply to Jank >>>

Believe it or not, for the most part I was enjoying the fencing, but unfortunately, somehow, for me it was the post of Chart 2, & as for my part maybe it was my reply to Chart 2, words started to be directed to the individual/s, as opposed to the topic/s… Although entertaining for you, as for my part I apologize for the personal remarks.

I had posted the following, with regard to the D Vs the N > “In reality the N indeed defeats the D. In my tables N indeed defeats the D. But we are not talking reality here, as the two never fought (F4U vs. P47, or P47vs P47). So I'm taking this posture, D as opposed to N, for the following reasons... @ combat weight, on production versions, the D's superior turning rate & climb combined with it's level stall characteristic on my personal dogfighting scale, defeats the D's roll & speed advantage.” <

I made a typo, the last words should have said, …@ combat weight, on production versions, the D's superior turning rate & climb combined with it's level stall characteristic on my personal dogfighting scale, defeats the N's roll & speed advantage.”
Now since you need convincing… I’ll expand:

1st I need to qualify something… I’m not a pilot. I served in the USAF as a sheet metal mechanic, & took flight lessons then (1980), and rode in the trainee’s seat a few times in T-38s, but never got a license, & they say I’m color blind. Now, at 45, the closest I’ve come, I’ll ever come to dogfighting for ‘real’, like most (obviously not all) of us, admitted or not, is in a sim. You read my sim post, I imagine, so you know I know the sim is not real (I like to think it is at times), but like these letters I’ve combined into words, using them in a manner that allows a simulation of talking with you, I’ve tried for years to make the aircraft respond as they would, this is not to say that they are indeed real, much like the fact that you can not hear the cadence of my speech; however to me, the meaning of the ‘stat’ is portrayed in a much more convincing manner than simply the numbers, stats, & figures, ‘unanimated’ staring back at me on a piece of paper, or screen. Perhaps we may all accept, one day, that a sim, like a video is not real, like these words, any words are not ‘real’, but they all can, when properly used, do a dam good job of helping us understand what happened/s in reality. Finally…

OK the promised expansion… I imagine the ‘meeting’ of the contestants, the ’47? & F4U-4 to be one on one, & a dogfight, as a joust between the two is a draw, or at best, luck. Accepting the dogfight scenario (simulation), low speed attributes outweigh high speed attributes. I consistently read that WW2 dogfights happened at speeds centered around 200 to 250, depending on the year, & combatants. This is not to say that the initial contact was made at that speed, only that the ensuing dogfight happened at that speed. No matter the praise each advocate has for their respective mounts, no actual WW2 Corsair pilot, & no T-bolt pilot has said in print that their plane was a dogfighter, at least not one I have seen; with the exception of an article I found at (http://home.att.net/~historyzone/F4U-4.html), written in praise of the F4U-4, which says it was indeed amongst the best dogfighters of the era. At these speeds, the N no longer has a ‘speed advantage’. The N’s semi-laminar flow wings perform best at speeds above 250, and without these high speeds, it’s performance decays faster than the D’s decay. I know that some question my tables, but for now, it’s the only document we all can have, check it out. http://www.ww2aircraft.net/forum/vie...=962&start=520

[DerAdlerIstGelandet]

Interesting conclusions there. I have enjoyed reading all of this. I have not said much because I am just trying to take it all in. Seriously very interesting stuff, all of you.

[syscom3]

It certeinly is an eye opener to see the info.

I salute Mr Goldberg for actually trying to quantify what plane is best. Plus there is a lot of constructive arguments coming from several people to keep the topic on course.

This is almost like seeing a thesis being generated by a student then dissected by experts.

[DerAdlerIstGelandet]

Yes I agree with you. At the same time though I do not believe that charts, graphs, numbers, and sims can accuratly tell you what aircraft was the best.

[FLYBOYJ]

Yep- Mr. Goldberg I commend you!

[Sal Monella]

Jon,

When I keep saying, "Where did you get your data?", I am really making a point like, "Did you pull that out of your rectum?" or Did you just plug in "P-47" into your web search engine and write down what came up?"

Garbage in, garbage out. You will notice that the various websites you have cited to are inconsistent with each other and at variance with the data I have provided below.

We still disagree on comparing the combat weight P-47N against the combat weight P-47D-25 or any other "D" model for that matter as the P-47N is carrying an additional 2,500lbs of fuel over the D-25's capacity. The D-23, by the way, had an internal fuel capacity that was 100 gallons less than the D-25 so there was an even greater fuel differential between the "N" and D-23.

I erased that comment about the D-23 not having the paddle blades because I remembered that I was wrong. Your data on the climb rate of the D-23, however is still in error, It was 2,920fpm. It had a greater climb rate than the D-25 because the D-25 was burdened with an extra 100 gallons of fuel in its internal tanks.

At any rate, in the interest of accurate information, I invite you to modify your charts to reflect the following where appropriate, or to take notice where the outputs from your data does not reflect the facts in the following data.

Wing area is 322.7sqft. ("D" model is 300sqft)
Length is 36'3-1/4"
Wingspan is 42'8"
Height is 13'7"

The total aileron area is greater than the "D" by 2.27sqft ("D" model is 25.7sqft)
The total wing flap area is greater than the "D" by 6.4sqft. ("D" model is 39.6sqft)

Empty weight is 10,998lbs. Combat weight is 16,330lbs. (Yes, those number are correct. Hopefully, you can see my point now.) Maximum takeoff weight is 21,198lbs. If we were to load up the "N" with the same internal fuel load as the D-25 model, it would weigh 13,850lbs.

Top speed at 32,000ft at combat weight and 72" HG is 453mph. The "N" can in fact do 467mph, just not while carrying a full internal fuel laod. The 467mph figure that is widely referenced is with an internal fuel load equivalent to the D-25 (100 gallons greater than the D-23). At 5,000ft, at combat weight and 72" HG, she can do 371mph.

The climb rate for the "N" at combat weight (16,330lbs) at 5,000ft and 72" HG is 2,950fpm. This is no small feat. The P-47M with a full internal fuel load (equivalent to the D-25) weighs just 13,275lbs. It can pull 3,775fpm at 5,000ft and 72" HG.

If the P-47N were to be loaded up with a fuel load equal to the "M" and D-25 (100 gallons greater than the D-23), I have no doubt that it would climb at 3,650fpm as it would weigh just 575lbs more than the "M" and has a greater wing area.

The "N" at a fuel load equivalent to the "D-25" would out turn any "D" model as it has a significantly more powerful 2,800hp engine and a greater wing and control surface area. The D-25, in combat weight, weighed in at 14,247lbs which is heavier than the "N" model with the same ammunition and fuel load (13,850lbs.)

Lastly, here is a tidbit that I would venture no one on this board is aware. The "N" model was designed to carry, in place of external fuel tanks, up to 3,700lbs of bombs!

[JonJGoldberg]

Reply to Sal Monella >>>

This has been fun, try your best to stop making this personal, my sphincter, and what I do with it is not open for discussion here, I believe there is a thread for off topic things, where you may be able to satisfy your newly found interest. Please note, as I have not posted anything there, all data has been extrapolated using the best available models.

More on topic, I feel we are getting to be repetitive… but I have a new angle for ya…

This time, in effort to beat the eraser, I’ll start from where you started: Like most of us, it seems we must each edit data that is available. We all must extrapolate the data we find. I tried to point this out using the Cradle of Aviation article you asked I read. I posted the info given for the XP-47J to show that we all (yes including myself) are guilty of being able to slant, & ever so slightly taint things ‘our way’ even when we know better. A better example (within Sal approved data) I can not, as of yet, find; how in the world (of sim reality & beer) can an aircraft, whose best climb rate, taking what was printed at face value, be 4,900 ft/min @ SL & 4,400 ft/min at 20,000 ft reach 20,000 in 4min 15 sec.? Want to know; Mother Nature has an opinion, guarding the ’47, as it was her favorite plane of the time, she aided the craft with a well placed blast of her nostril… There fore defeating the best mathematician at there own game as she hates being quantified. So yeah, I decipher what I see, as you do. Take your beloved service manual, better yet, the service manual for a T-38 (I choose this aircraft as it is not a fighter; an aircraft whose service manual, I’ve seen, OK about 20 years ago, but I saw it, & I figure represents both neutral ground, & higher level of production). On the flight line, there was not a single pair of aircraft that exactly matched. When they left the factory, each was slightly different, they are built using jigs, & by people. The sheet metal skins never had the rivet holes in exactly the same place. Replacement parts were/are in field tailored from their ‘factory’ stampings to exactly match their intended recipients. As a matter of fact, the factories normally produce these pieces (skin) ever so slightly different than original to allow ‘fitting’, or they are remanufactured in field using measurements from the donor for this reason. So with regard to the spec within your service books; it seems you expect my data to match yours exactly. It can’t. Mine was taken from serial number ‘x’ and yours from ‘y’ it says so on the cover of my service manual. My plane is 158 lbs heavier than yours, at combat weight, climbs 180 ft /min slower, & goes 11 mph faster. All these numbers seem just impossible to you, & just ‘plane’ hogwash. You are entitled. As for me, the worst number here may be the climb rate; ((180/2900)*100) I’m off 6.2% from your bible, & that, according to you, is just completely out of the ball park… your sending the clean up crew after the ‘litter’. Mind you, I’d take a 6.2% improvement in my income, so this number is significant, to be sure, but it is hardly grounds for dismissal; we should be able to work on this together, as I’m willing to ‘fix’ my data; please just send me a copy of the original, or point me as to where to acquire it, I left E-mail address, & you can see them in my profile. No more slander OK, the data is not WRONG, your data is not wrong. Climbing to 20,000 ft in 4min 15 sec, in an aircraft whose best climb rate is 4,900 ft/min, that’s wrong.

For a closer look at how combat weight within my tables are determined: I started with 10997 lbs (funny, practically the same number, somebody please fill the tires), to which I added a 225 lb pilot, 75 lb radio, 30 lbs fudge factor (maybe the pilot naked is 225, maybe the radio weighs more, maybe there was 5 gallons of gas stuck from the last flight), 529 lbs of guns (M2=66.1 lbs), 1296 lbs of bullets (5.184 oz/round) @ 500 rpg & 3336 lbs of fuel (6 lbs per gal/556 gal). This brings me to my ‘combat weight figure’. I propose your Republic book & I have one or more of the following happening, we have different pilots in mind, & or a different amount of ammo.

As for the rest of my numbers, again they do not exactly match yours, we may argue about .3 sq foot of wing area, & a ¼ inch in length; I feel as if this would not warrant a letter home to mama, you feel as if they disqualify my stats. OK.

But Sal, I have hope in you.

On Match Rules: We’re going to race a semi, against a pick up truck at a drag strip. These two anonymous vehicles, although designed for clearly different purposes have in common the ability to tow a 14’ power boat on its trailer, my intended ‘job’ for these vehicles, & a sales man. I’ve told the salesman, who’s paid by commission, to apply my deposit on the victor, as beside towing the boat, I want as much acceleration as I can get, that’s what I want; & of all the vehicles here, it’s between these two. Now the semi is 10 times the price of the pick up, so the commissioned sales man says, hey Einstein (or bub), tell you what I’m goanna do, I’m goanna make this fair. The semi is currently equipped with 4 extra tires, 1 extra axel, a hitch that weighs a lot more than is required, & it’s got the capacity for all this extra gas. Now I promise that you will receive all of the features & capacity of whichever truck wins, but I’m goanna take all this unnecessary stuff off, just for this race, so that you may more properly judge the results. Now it’s clear that I would not accept these terms, & further it’s clear what the objectives are all around. I find the race as probable as our dogfight, & we each see the other as the salesman. I’m not convinced that I’m in any way handicapping the semi, by requiring the salesman to keep the vehicles as they are, & feel it wasn’t be proper for the salesman to suggest loading the pickup with 4 semi tires, axel, and fuel tanks, as either which way, I’m screwed! …So much for your bomb analogy.

Happy Bird Day To All

[FLYBOYJ]

Originally Posted by JonJGoldberg

Take your beloved service manual, better yet, the service manual for a T-38 (I choose this aircraft as it is not a fighter; an aircraft whose service manual, I’ve seen, OK about 20 years ago, but I saw it, & I figure represents both neutral ground, & higher level of production). On the flight line, there was not a single pair of aircraft that exactly matched. When they left the factory, each was slightly different, they are built using jigs, & by people. The sheet metal skins never had the rivet holes in exactly the same place. Replacement parts were/are in field tailored from their ‘factory’ stampings to exactly match their intended recipients. As a matter of fact, the factories normally produce these pieces (skin) ever so slightly different than original to allow ‘fitting’, or they are remanufactured in field using measurements from the donor for this reason.

Just to ping off JJs comments - although aircraft from WW2 to today's fighters are mainly built up in assembly jigs, once in the field they tend to "grow" in one direction or another. Its very hard to use a cannibalized skin from one aircraft to another because rivet holes will be slightly off. Any time skin repairs are accomplished, the preferred method is to manufacture a "blank" sheet line it up where it should be and "back-drill" the rivet holes using the existing structure as a template.

Anytime you start changing major structural components in the field because of damage, especially damage that placed large loads on the airframe, the aircraft will never be the same. Many times it will possess some abnormality ( flying crooked, requiring more trim in a certain configuration, not achieving the max speed as indicated in the flight manual). I've also seen "positive" results from major field repairs as well, but those are far and few....

JJ - I hope you don't mind me addressing you that way, being a former New Yorker, it only seems natural...

[JonJGoldberg]

Reply to FLYBOYJ >>>

JJs OK, You may...

You are 100% correct with your above post, about growth, & repair... but I had a specific event in mind... I was stationed @ Edwards in 1981; we recieved two new T-38s for the pilots training school there. After the crew chiefs set the planes, they were to be refuled, & sent on thier way within two hours. An APU truck clipped the left wing of one and the right of the other (the driver had a heart attack). It was suggested by the Sgt. in charge (I was an airman) to the commander, that in order to save time, the dammaged panel from the one with lessor dammage be replaced with the other's as they were new, less than 50 hour flight time on each, & in that way we may be able to release one of them on time. Before removing the panel from the healthy plane, the dammaged section was placed on top; we wound up building the parts from scratch, as the devations were obvious. Not that I thought it was a good idea to begin with... The next day the T-38s were on thier way.

[FLYBOYJ]

Edwards 1981? I used to live in the Antelope Valley. I worked on occasion at Edwards and used to fly there with the Aero Club. The whole area is a lot different today...

[syscom3]

I used to go four wheeling near Mojave in the 80's. California City to be exact.

[FLYBOYJ]

Yep - Cal City, I used to fly there allthe time, they had cheap aviation fuel.

[JonJGoldberg]

...Man that was a while ago. Last time I was back there was '95, on my honeymoon (We landed in Vegas, stayed two days, then for two weeks armed with a Caddy from Hertz, traveled from Vegas, to the Grand Canyon, to 4 corners, to LA, to SF and flew home from there) & already things were different. Pomdale raceway had expanded, my Trailer Park & the Drive In were gone... even the intersections at the wind factory (can't remember the name of where all those wind generators are) were busy. My favorite 'derelict' places were now accessible... I was pretty much a lost soul back then, guess I still am.