Aces High Bulletin Board
General Forums => Aircraft and Vehicles => Topic started by: Raptor on October 11, 2009, 03:20:37 PM
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I am just now getting to be acquainted with the plane comparison charts but I find it interesting how well the P47D-11 performs. I have always known it was the most agile, but I didn't realize it was the fastest until the M.
This shows it is even faster than the N at mil power until 30,000ft.
(http://bbs.hitechcreations.com/newscores/genchart.php?p1=46&p2=83&pw=0>ype=0)
Here the D-11 and M are nearly identical in speed until 25,000ft
(http://bbs.hitechcreations.com/newscores/genchart.php?p1=46&p2=102&pw=0>ype=0)
The main counterpart that distinguishes the N and M from the D-11 is WEP, both the D and the M model have more effective WEP than the D-11.
The D-11 outclimbs the N until around 30,000ft mil power and 8,600ft with WEP. However, the M climbs better than the D-11 at all altitudes.
What I want to know is how does the M compare to the D-11 in turning? Are all of the D-11 pilots going to drop it for the M?
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Probably not, unless they already left the D11 for the N.
See the comparison for the D11, D40, and N at Gonzo's page:
http://www.gonzoville.com/ahcharts/index.php?p1=p47d11&p2=p47d40&p3=p47n
Note the N (as always) "looks" worse only because it has so much more fuel onboard.
Here you can see the D40/N comparison with a lightly loaded N model:
(http://www.nakatomitower.com/71sqn/p47chart3.jpg)
It just about matches the D11 for milpow climb, and bests the D40 for WEP climb.
Also note that when the P47M takes overload ammo (as 99% of all of them seem to be doing, orbiting for hours spraying thousands of rounds and then running away -- they'd run out of ammo if they took the historic loadout), it only makes 3200fpm with WEP.
The M specs are very very close to the N when the N is loaded lightly, and this I've been saying for ages. Yet very few seem to fly it exclusively. I think the same will be true of the 47M -- folks will still switch up their 47 choices based on their mood or mission profile.
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That only tells you turn radius, not turn rate. Before the M was introduced, many of us already knew that the N could out duel the D-11. Belief that the D-11 is a better dogfighter than the N is merely belief.
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The N has a higher empty weight (around 1000lbs according to my foggy memory) than the D models. The D11 has lowest drag due to the cage & razorback configuration and no wing pylons, besides being slightly lighter (empty). All jugs have similar military power. Therefore on mil power the D11 is the best performer and N is the worst. As a ground pounder, the D40 with the exact same loadout and absolute fuel load in gallons, clearly out climbs the N on mil and will get to the target first. The only advantage of the N is the better ability to get away after the drop.
The D11 is different from all the other jugs by not having the paddle blade prop. This has a minor effect on speed (actually faster with the toothpick), but a much more pronounced negative effect on climb-rate/acceleration. This is what makes the climb-rate difference between it and the heavier, draggier D25/40.
The M/N have caffeine injection system that makes all the difference. In these 5 minutes of joy they blow the D models out of the water. 5 minutes is often all you need, but not always.
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Was under the impression the M could climb to 20k on WEP. I have also read the climb rate should be 4k/min initially. This does not seem to be the case. Any thoughts on why?
http://www.wwiiaircraftperformance.org/p-47/p-47.html (http://www.wwiiaircraftperformance.org/p-47/p-47.html)
Infidelz.
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Was under the impression the M could climb to 20k on WEP. I have also read the climb rate should be 4k/min initially. This does not seem to be the case. Any thoughts on why?
http://www.wwiiaircraftperformance.org/p-47/p-47.html (http://www.wwiiaircraftperformance.org/p-47/p-47.html)
Infidelz.
Not modeled with 150 avgas my best guess.
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Weight?
With 25% fuel and the 8 gun, 267rpg package, the M gets 3900fpm initially and climbs to 19K in ~5 minutes.
Edit: Your source lists time to climb to 15K with WEP as 4.2 minutes. This seems pretty ballpark with the test figures I got above.
Was under the impression the M could climb to 20k on WEP. I have also read the climb rate should be 4k/min initially. This does not seem to be the case. Any thoughts on why?
http://www.wwiiaircraftperformance.org/p-47/p-47.html (http://www.wwiiaircraftperformance.org/p-47/p-47.html)
Infidelz.
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Weight?
With 25% fuel and the 8 gun, 267rpg package, the M gets 3900fpm initially and climbs to 19K in ~5 minutes.
Historically it only ever carried the "normal" loadout (267 rds) and some sources say only ever had the 6 guns onboard.
As for fuel, very rarely has a WW2 plane been test flown by the USAAC/USAAF with so little fuel onboard. It's not representative of the real thing.
As usual, the "4000fpm" quotes were overly optimistic, and the comparisons that LIST 4000fpm-type climb rates are usually questionable in many ways. More reputable sources say climb rates in the mid 3000s or lower.
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That report has "combat" weight at 13262. I haven't looked at the weights in game, but it does list the MG load at 6.
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Could reach 20k implied to me that it ran wep the whole time (from below quote). I can get to 16k on wep with full fuel and 8 50cals. Haven't tried 6 50cals.
In mil power the average ROC (see below) to 20k is 3500 fpm. That is pretty sporty. In WEP it says the average ROC is 4210. Holy bat snot. That is well outside anything posted before.
I read it at the following:
http://www.geocities.com/Pentagon/Quarters/9485/P-47M.html (http://www.geocities.com/Pentagon/Quarters/9485/P-47M.html)
"P-47M performance was as follows:
Max speed: 470-480 mph @ 28,500 ft. Climb, at max. gross weight (including three 75 gallon drop tanks): 4.9 minutes to 15,000 feet at 2,600 rpm (1700 hp). Reportedly, the "M" could reach 20,000 feet in 5.7 minutes at military power (2,100 hp @ 2,800 rpm). 20,000 feet in 4.75 minutes in WEP (2,800 hp @ 2,800 rpm). This is with full internal fuel and ammo. No external stores or drop tanks. In other words, normal load, clean configuration."
With these specs I think it would have to be perked.
But this is why I asked the question.
Infidelz.
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The plane is a beast - but I dont think its any more perk worthy than a K4, solely from a performance standpoint.
However, should over-use become a factor, I have no problem assigning a small perk to it.
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The plane is a beast - but I dont think its any more perk worthy than a K4, solely from a performance standpoint.
However, should over-use become a factor, I have no problem assigning a small perk to it.
:rolleyes: :rolleyes: :rolleyes:
So you know its no better than the K4 with its inconceivable 20eny (In fact you know as well as I do that a K4 will WHOOP it in a duel between equal pilots) yet you want to perk it anyway, because its popular? What, are we perking on the basis of having white stars and curvacious women in in the paint-scheme now? :neener: :neener: :neener: they perk the M, they will sure need to perk the Kurt AND the D9.
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:rolleyes: :rolleyes: :rolleyes:
So you know its no better than the K4 with its inconceivable 20eny (In fact you know as well as I do that a K4 will WHOOP it in a duel between equal pilots) yet you want to perk it anyway, because its popular? What, are we perking on the basis of having white stars and curvacious women in in the paint-scheme now? :neener: :neener: :neener: they perk the M, they will sure need to perk the Kurt AND the D9.
Hmm...
Im thinking you misread what I wrote; that or simply chose to assign your own meaning. I say this because, if you read again, I think youll find that we have no disagreement when it comes to performance-specific perk criteria.
That said, youll note my mentioning of over-use in the post. Although exclusive of peformance, it factors into whether or not an airplane is perked.
Lotta bunched panties in here today.
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I was not advocating a perk for the present performance in game. Just suggesting that it was probably perked during World War II for the performance I referenced above.
Also wondering about the dive brakes. Have to try them tonight see what they do.
Infidelz.
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The Luftwafffe officially considered that their captured P-47D Razorback (with needle-tip prop!) generally much out-turned their (non MW-50) Me-109G-6 in flight tests. (On Special Missions: KG 200)
Unlike with the P-51D, almost all of the 600 P-47 combat reports, on the Mike Williams "WWII Aircraft performance" site, show a very rapid gain in level turns by the early '44 P-47D on the Me-109G at all altitudes, even in left-hand climbing(!) spirals against gondola 109Gs, usually in less than four 360° turns from the merge... This somewhat excepted turns to the right where the Razorback was still superior but MUCH slower gaining...
The Bubbletop D was around 1000 lbs heavier than the Razorback, and turned slightly worse than even a P-51D Mustang.
I doubt any of the later Bubbletop variants could match the early '44 Razorback turn performance in those combat accounts, but power and wing area could create an upset with the N maybe?
It should be remembered that when the P-47D Bubbletop was being introduced, the P-47D was in the process of seeing a massive change of role, from escort fighter to ground-attack aircraft... The Bubbletop was essentially a ground-attack aircraft first and foremost, and everything about it was optimized for that role.
Gaston
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The Luftwafffe officially considered that their captured P-47D Razorback (with needle-tip prop!) generally much out-turned their (non MW-50) Me-109G-6 in flight tests. (On Special Missions: KG 200)
Unlike with the P-51D, almost all of the 600 P-47 combat reports, on the Mike Williams "WWII Aircraft performance" site, show a very rapid gain in level turns by the early '44 P-47D on the Me-109G at all altitudes, even in left-hand climbing(!) spirals against gondola 109Gs, usually in less than four 360° turns from the merge... This somewhat excepted turns to the right where the Razorback was still superior but MUCH slower gaining...
The Bubbletop D was around 1000 lbs heavier than the Razorback, and turned slightly worse than even a P-51D Mustang.
I doubt any of the later Bubbletop variants could match the early '44 Razorback turn performance in those combat accounts, but power and wing area could create an upset with the N maybe?
It should be remembered that when the P-47D Bubbletop was being introduced, the P-47D was in the process of seeing a massive change of role, from escort fighter to ground-attack aircraft... The Bubbletop was essentially a ground-attack aircraft first and foremost, and everything about it was optimized for that role.
Gaston
Tell that the the 56th Fighter Group w/ over 1000 e/a confirmed destroyed. (yes, in the air and on the ground)
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It should be remembered that when the P-47D Bubbletop was being introduced, the P-47D was in the process of seeing a massive change of role, from escort fighter to ground-attack aircraft... The Bubbletop was essentially a ground-attack aircraft first and foremost, and everything about it was optimized for that role.
Gaston
While its role was changing, the aircraft was still optimized for its original role--that of an interceptor. Otherwise, they'd have gotten rid of the turbo and made it a pure supercharged plane. The aircraft was not reconfigured in any way (from the late model razorback D-22/23) to make it more useful for ground attack. In fact, the move to a bubble-top was made in order to increase the visibility of the pilot for air-to-air. Also, the main increase in weight between the early D and later D's was increased fuel, and not structural weight.
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-Could be true about the fuel weight. I think an issue could have been a modest change in CG. Judging from tests, there is no way the later Bubbletops could turn as well as the Razorbacks, but the reason for that could be aerodynamic, CG, keel area (a big difference!), typical weight, the lack of wing pylons, canopy drag, all combined to tip a non-linear balance.
One of the things overlooked in simulations is that performance deterioration with weight, aerodynamics or CG is not something strictly linear, but a deterioration that probably occurs in a series of "steps". Thus one aircraft gains 300 lbs with very modest changes in performance, while another's performance takes a big drop from the same 300 extra pounds. What I mean is that performance changes are not predictable: I agree that the Razorback should NOT have a big edge on the Bubbletop in turning. We fully agree on that. In practice, it seems like there WAS a big difference: The Razorback out-turned EASILY the Me-109G-6, by the Luftwaffe's own account, which Me-109G-6 was very close, or marginally better at low speeds, than the P-51D, which was noticeably (10-15%+) better-turning than a P-47D Bubbletop... All this from actual tests, not my opinion...
Quote: "While its role was changing, the aircraft was still optimized for its original role--that of an interceptor. Otherwise, they'd have gotten rid of the turbo and made it a pure supercharged plane. The aircraft was not reconfigured in any way (from the late model razorback D-22/23) to make it more useful for ground attack. In fact, the move to a bubble-top was made in order to increase the visibility of the pilot for air-to-air."
-They did the same thing to the Typhoon, which was stricktly a ground-attack aircraft. The Bubble canopy was incidental: You need it just as much, or more, when attacking low on the ground, to check for diving enemy fighters: Actually a more likely occurence than up at high altitude...
They did indeed never re-configure the P-47, so the poor thing was lugging around a VW-Beetle sized turbocharger, with huge ducting, all of which was of absolutely no use to it for most European fighting after June of 1944...
One Army high-ranking official put it in an amusing way: "We designed the P-47 for high altitude escort, and the P-51 for low-altitude ground-attack. Given how they both ended up serving, it's a wonder we won the war!!"
Actually that huge turbocharger is one of the major reasons I don't like the later Bubble P-47Ds compared to the earlier Razorbacks: The aircraft had tremendous qualities that allowed it to be one of the best fighter-bomber of the war (except maybe for the Corsair's valuable dive-bombing ability?), and yet much of the superb engineering that was put into it was counter-productive to its later, most valuable role...
It did break the Luftwaffe's back at the moment it was at its strongest, scoring 140 out of the 220 air-to-air kills of "Big Week", a period after which some US pilots said "the Luftwaffe was never the same". For the reliability of its guns alone I would, as a pilot, always have preferred it to the Merlin P-51, whose jamming tendencies in hard turns was never really fully cured (read the P-51 reports page on "WWII aircraft performance": Many Mustang kils were claimed with one gun, even on the D!).
But as an efficient use of Power, energy and elegance in design, it certainly wasn't at the front row!
Gaston
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The bubble top replaced the razor back because the visibility was a greater advantage than what a few mph or dps give. Most real pilots flew with icons off and died to a plane other than the one they were looking at.
The turbo supercharger was never yanked out from the P47 because it was impossible. It practically required a new plane and not like it did any real harm. They managed just fine. See also: P-38.
The P47 was replaced by the P51 in the high alt role not because the P51 was a better fighter up there. Many would claim it wasn't. P51D could fly longer on less fuel and cost less than a P47. Simple logistics win wars. Anyway, by the time the P51D was running in full force it didn't really matter anyway who was flying up there, so it might as well be the cheaper ones. As a fighter bomber the P-47 had a clear advantage over the P-51. Fighter bombers do not dogfight that much, so the "bomber" part is more relevant than the performance advantages at low alt.