Aces High Bulletin Board
General Forums => Aircraft and Vehicles => Topic started by: SgtPappy on May 11, 2010, 12:59:16 PM
-
Upon reading an article by Robert Mikesh published in 'The Great Book of WWII Airplanes', I came across what the author states was a comparison test done with the Model 52-? Zero (A6M5-?) versus the F6F-5 and the F4U-1D. The Americans had captured, rebuilt and flown several of these claimed 'Model 52 Zeros' during the battle of Saipan, June 1944.
"F4U-1D vs Zero 52:
Both aircraft were flown side by side, making all things equal at the beginning of this flight comparison test. In a race for altitude, the best climb of the F4U-1D was equal to the Zero up to 10,000 feet, above 750 ft/min better at 18,000 feet and above 500 ft/min better at 22,000 feet and above. Best climb speeds of the F4U and Zero were 156 mph (135 kts) and 122 mph (105 kts) indicated airspeed respectively"
Now you may think... 'What? The A6M5b in our game destroys any F4U-1A that's using WEP in the climb rate. Perhaps the Zero in the test was flown incorrectly' But listen to this; the F6F-5 vs. the A6M5:
"F6F-5 vs Zero 52:
The Zero climbed about 600 ft/min better than the F6F up to 9,000 ft, after which the advantage fell off gradually until the two aircraft were about equal at 14,000 feet. Above this altitude, the Hellcat had the advantage, varying from 500 ft/min better at 22,000 feet, to about 250 ft/min better at 30,000 feet. Best climb speeds for the F6F-5 and Zero 52 were 150 mph (130 kts) and 122 mph (105 kts) indicated, respectively."
This is very strange... either the Americans didn't fly their F6F-5 at maximum capability and the Zero was not performing properly or there is something amiss in the climb rates of these aircraft in the game.
Essentially, the F6F-5 vs the A6M5b in our game is completely opposite to the test. Our F6F-5 can only outclimb the A6M5 using WEP, and only from 0-4000' and from 12000-~15500'. Above that, the Zero is better in climb all the way up.
An F4U-1D, even with WEP, cannot hope to come close to either the Hellcat or A6M5 climb rate in AHII. In-game now, the F4U-1D only out climbs the A6M5b during a tiny interval of altitude from 12000-14000 feet.
Can anyone explain the strange findings?
I wish I had the data as to the engine settings each plane was using at the time but I cannot find them.
-
well, 2 replies:
First, there is no WEP in the zero in this game.
Second, that zero was heavily damaged and repaired, and at the time the US really had no idea how to operate it properly. It wasn't performing like Japanese versions would have. It was broken goods.
-
Jap pilots were smaller and weighed less than American pilots resulting in an overall lighter, faster and more maneuverable aircraft. Jap's dined on vegetables, tofu and brown rice while Yanks gorged themselves on burgers, dogs, fries and milk shakes. Also, sake has half the calories of American beer.
-
Jap pilots were smaller and weighed less than American pilots resulting in an overall lighter, faster and more maneuverable aircraft. Jap's dined on vegetables, tofu and brown rice while Yanks gorged themselves on burgers, dogs, fries and milk shakes. Also, sake has half the calories of American beer.
...
ack-ack
-
The A6M5 Type 0 Model 52 could climb to 26,250ft in 10 minutes.
ack-ack
-
:O
The A6M5 Type 0 Model 52 could climb to 26,250ft in 10 minutes.
ack-ack
-
Jap pilots were smaller and weighed less than American pilots resulting in an overall lighter, faster and more maneuverable aircraft. Jap's dined on vegetables, tofu and brown rice while Yanks gorged themselves on burgers, dogs, fries and milk shakes. Also, sake has half the calories of American beer.
*EDIT* Not even close vafii...
(http://www.merchco-online.com/includes/img.php?m=430&p=images/&i=besign5.jpg)
-
Could the fuel that was used have made the difference? Wasn't U.S. fuel of a higher quality than what the Japanese used and if that was true then a Zero with U.S. fuel would outperform a Zero with Japanese fuel.
-
Could the fuel that was used have made the difference? Wasn't U.S. fuel of a higher quality than what the Japanese used and if that was true then a Zero with U.S. fuel would outperform a Zero with Japanese fuel.
Only if the engine was designed for the high grade fuel. The Ki-84's engine was actually designed for fuel the Japanese didn't have access to, I am not sure that is the case with the older A6M5's engine.
-
Jap pilots were smaller and weighed less than American pilots resulting in an overall lighter, faster and more maneuverable aircraft. Jap's dined on vegetables, tofu and brown rice while Yanks gorged themselves on burgers, dogs, fries and milk shakes. Also, sake has half the calories of American beer.
Although your right that the average Japanese pilot was usually smaller then his American counter-part, and US testings of the Zero usually note this with complaints of the size of the cockpit(which would be sufficient for a Japanese Pilot). I really doubt a gross difference of 20 - 40lbs at best made any noticeable difference.
-
Regardless of the Zero's performance in these tests, we can see that the Hellcat cannot outlimb the F4U-1D in these tests. This is indeed strange, since AHII says the opposite.
The bigger picture here is that these two American Muscle planes seem very different in-game than in real life, unless someone can prove as to how these aircraft were tested.
EDIT: Also Krusty, I don't think I stated or the test stated that the Zero was on WEP. Then again, unfortunately, the test states nothing of the engine settings on any plane. But let me reiterate that whether the Zero was up to snuff or not, it was tested the same method against both USN birds (as far as the test shows us) and the F4U-1D outclimbs the A6M5 while the Hellcat only does so at high altitudes. So perhaps there is a problem with the F6F-5 testing method, or something is modeled strangely in the game.
I honestly doubt it's the latter, but this test deserves much speculation, and I don't think it should be ignored.
-
These are good questions ( I would also like to know why) but if you try to use the set auto-climb to outclimb almost anyone in an F4U you're probably going to get killed. Get it to it's top speed and it climbs almost as fast as in autoclimb and it will pull away from most other planes.
:bolt:
-
The average weight of Japanese pilot was 120lbs vs 180 for American pilots. Jap aces Saburo Sakai and Hroyoshi Nishizawa weighed a mere 122 lbs each. That's a 60lb difference right off the bat! Now add in gear, flight suits, parachutes, etc. and the weight differential is even more dramatic as Japanese pilots chose not to wear parachutes (even when ordered to do so). The Zero, like most Japanese planes, was extremely fuel efficient as opposed to the American gas guzzlers, allowing Japanese planes to carry a lighter fuel load. Not to mention the Zero weighed a mere 5,000lbs, half the weight of American planes. All this resulted in better performance, better climb rate, etc..
-
A6M5b weighs more then 5,000lbs at combat weight. Also, you seem to be forgetting why it weighed so little in the first place, it had to do with that 1,100HP engine is was forced to use. Comparatively to American planes it fought against like the F6F: 2000HP, F4U: 2,400HP, P51D: 1,700HP(I think), etc, etc.
-
The average weight of Japanese pilot was 120lbs vs 180 for American pilots. Jap aces Saburo Sakai and Hroyoshi Nishizawa weighed a mere 122 lbs each. That's a 60lb difference right off the bat! Now add in gear, flight suits, parachutes, etc. and the weight differential is even more dramatic as Japanese pilots chose not to wear parachutes (even when ordered to do so). The Zero, like most Japanese planes, was extremely fuel efficient as opposed to the American gas guzzlers, allowing Japanese planes to carry a lighter fuel load. Not to mention the Zero weighed a mere 5,000lbs, half the weight of American planes. All this resulted in better performance, better climb rate, etc..
Still missing the big picture here though. Of course the Zero's climb rate is strange and can be explained due to a number of things, but really, the thread was meant to show what the A6M5's climb rate revealed versus the Hellcat and Corsair.
IF the Zero was flown exactly the same against both planes (which is likely a safe assumption), then clearly, the F4U-1D is supposed to out climb the F6F-5. Which it doesn't in-game. Has anyone used the suggested climb speeds of 156 mph for the F4U-1D and 150 mph for the F6F-5? If there's a difference in climb rates there, perhaps it will match the test results.
I also found the original test I first posted here: http://www.wwiiaircraftperformance.org/f4u/p-51b-f4u-1-navycomp.pdf (http://www.wwiiaircraftperformance.org/f4u/p-51b-f4u-1-navycomp.pdf)
-
Let's just say this myth has been busted.
-
Let's just say this myth has been busted.
Uh no it hasn't...but I'm not in the mood to point out where the missed points are.
-
Has anyone used the suggested climb speeds of 156 mph for the F4U-1D and 150 mph for the F6F-5?
I had read the same test (I think) in the book "Zero Japan's Legendary Fighter."
I have set my autoclimb to 158(I forgot it should have been 156) in the F4U-1A.
Although I have not used a stopwatch or any other means to test it seems to me that the -1A climbs better at that speed. I do realize the tests were done w/ a 1D but, I figured that the performance would be very close with an edge to the 1A.
When I say climbed better it might be a couple hundred feet a minute..........This is an appearance and I don't know how accurate it would be.....But what the hell? It can't hurt.......
-
I don't know how to make graphs but if someone could plot Noah's test results (i.e. F4U-1A/D, sustained climb @ 156 mph) against an F6F-5's climb rate at 150 mph, then maybe we can get a better bearing on climb rates here.
Does anyone know if the climb rate data posted in the scores & stats page are done at 160 mph for all aircraft? Because as far as we know, every plane essentially has a best climb speed, but auto-speed sets our climb speed to 160 mph default in each fighter.
EDIT: Sorry people, I posted the wrong link to the test earlier. This is the actual test: http://www.wwiiaircraftperformance.org/japan/ptr-1111.pdf (http://www.wwiiaircraftperformance.org/japan/ptr-1111.pdf)
-
This graph shows the comparative performance of the 1D and F6F. Doesn't specify what speed the climb performance was tested at, however:
(http://bbs.hitechcreations.com/newscores/genchart.php?p1=11&p2=33&pw=2>ype=2)
The chart shows a clear advantage going to the F6F at nearly all altitudes.
Here's an interesting one:
(http://www.wwiiaircraftperformance.org/f4u/17930-climb.jpg)
From the BuNo. this is likely an F4U-1A. Another one:
(http://www.wwiiaircraftperformance.org/f4u/50030-climb.jpg)
Once again, from the BuNo this is most likely a 1A.
Comparison an F6F-5:
(http://www.wwiiaircraftperformance.org/f6f/58310-climb.jpg)
No WEP on this one, but even under MIL the F4U-1A outperforms the F6F. This one shows a slightly different curve, (again, no WEP) but still surpassed by the 1A:
(http://www.wwiiaircraftperformance.org/f6f/72731-climb.jpg)
For some odd reason I'm not having much luck finding a climb chart with WEP noted on my search....
-
Thanks Sax.
If we can find the speeds at which those climb rates were attained, then we can conclusively deduce if our aircraft are climbing incorrectly. In all of Sax's charts, the F4U-1(A)'s all climb faster than 3000 fpm without WEP. Obviously not the case with our plane.
I did, however retry Noah's tests. I took the F4U-1A for a spin, set auto-speed to 156 IAS and the plane easily climbed at ~ 3100 fpm from sea-level. It went over 3200 fpm with WEP as I got higher and higher, but that obviously dropped quickly.
-
At higher alts. WEP makes even more of a difference in autoclimb at the 156~158 speed. It seems that it may be a few hundred feet better a minute difference from Mil to WEP at High altitudes. I've been spending more time climbing to 19k as this is the best top speed alt for the 1A (different blower setting maybe?)....Call me an "Alt Monkey" but it seems I'm running in to more 51's, 47's and, k4's up there every day....
Obviously fuel loads will vary the rate of climb. I flew the F6F in a fight briefly this morning. I normally "up" with 75% fuel as I did this morning.The F6F autoclimbing at the default rate did not seem to climb as well as the -1A with 75% fuel at the 156~158 MPH. Again the difference appears to be small in ft per minute but, if you're on autoclimb for 5minutes that could be a nice benefit.....Or perhaps I'm delusional as I have not had stopwatch or other means of testing lol. Admittedly my personal bias is towards the F4U. The higher speed and high speed climb is partially why it replaced the F6F anyway...Much better to get to and kill Kamikaze's that way. That and the demand for more fighters on board carriers.
For Hellcat jocks I mean no disrespect the F6F is a great plane and has some nice advantages too.
-
Jap pilots were smaller and weighed less than American pilots resulting in an overall lighter, faster and more maneuverable aircraft. Jap's dined on vegetables, tofu and brown rice while Yanks gorged themselves on burgers, dogs, fries and milk shakes. Also, sake has half the calories of American beer.
ummm.......
froger
-
Can any of our chart gurus confirm whether this indicates the rate of climb on the 1A/D/C is off, or is this something that was non-standard?
-
Does anyone know if the climb rate data posted in the scores & stats page are done at 160 mph for all aircraft? Because as far as we know, every plane essentially has a best climb speed, but auto-speed sets our climb speed to 160 mph default in each fighter.
In-game, each plane's default [alt-x] speed is set for best climb, as modelled by HTC. For example, compare default [alt-x] speed in the P-51 versus the F4U.
Now, that being said, as you increase altitude, best climb indicated air speed increases, but only slightly. Where the P-47 best climb is around 160 at sea level, above 25,000 feet, its around 165. Not to big of a difference really--a hundred fpm difference maybe.
Again, like all reports of this nature, we get a qualitative assessment by the pilots instead of hard, quantitative data. Without testing weights, power settings, rates of climb, climbing speeds, etc., we get a cloudy picture of the relative performance. If we were Corsair or Hellcat fanbois, we could desperately grasp to a report like this and cry "Look!, the F6F in-game is porked! It says so in this report right here!" Without the context of the test, its only interesting from a historical standpoint; it offers no "proof" of anything.
-
But in the case of the F4U/F6F when multiple tests, climb rate reports, etc. indicate that the F4U outclimbs Hellcat, while the situation is reversed in the game something seems off. Even under full fuel load, the F6F outweighs the F4U-1D slightly by about 300-400lbs with the same amount of engine power, (the 1A under full fuel is heavier, but she does have the extra wing tanks. If the 1A is at 75% the Hellcat weighs more by 100lbs) but when you look at the performance comparison chart for the game the Hellcat outclimbs the 1D by a pretty good margin at all but a very tiny band between ~11-13,000ft, and above ~17k.
-
Do we know however, that the R-2800-10W and R-2800-8W have the same power at sealevel? If they do, what Sax says about their respective power-weight ratios should allow an F4U-1D to climb faster. I assume the F4U is also more aerodynamic if the engines produce the same power since we know that the F4U is faster at sea-level.
Though let me also bring to the table the following speculation: I believe it has been mentioned before that Grumman was testing the Hellcat incorrectly at one point, and that other companies' tests (Vought, I think was one of them) concluded that the F6F-5 could exceed 400 mph in level flight. If all/most of the published tests out there are done with this possible 'incorrect testing', then we may never know what the Hellcat really performed like.
-
I suppose my question to both of you would be, why is there a discrepancy in-game? Everything in this game is controlled by mathematics. I would suggest that there is an answer out there that would explain the difference.
First start with the aerodynamic characteristics that affect climb rate. They are? Also, when a test flight says that the F4U "outclimbed" the F6F, what exactly does that mean? What is the quantitative difference in the flight test numbers?
-
Stoney, that answer is exactly what we are seeking.
There must be something to explain the discrepancy, but I wish I knew what the answer was. Though I am still curious about the F6F-5's testing discrepancies that Widewing mentioned before. I can't find that thread.
-
Pappy's on the ball. The couple charts and tests I've seen indicate something's fishy, however I don't have the information to determine what if anything is wrong. Hoping we can get some of the chart and stat gurus to lend a hand.
There's some charts out there with the 1A at nearly 4000fpm climb, however these I KNOW for certain are while testing overpowered settings (IIRC, it was something to do with pressure in the cylinder heads, that conversation was a while ago. Although I'd love to see it just to see the whines). We need someone with more information that can help sort this stuff out.
-
First start with the aerodynamic characteristics that affect climb rate. They are?
-
I suppose the straight- up aerodynamic cleanliness of the aircraft, thrust-weight ratio/propeller efficiency. The only things I can really think of right now.
-
I suppose the straight- up aerodynamic cleanliness of the aircraft, thrust-weight ratio/propeller efficiency. The only things I can really think of right now.
Excess power. If you do power available/power required analysis, you'll probably be closer to finding what you're looking for.
-
Again, like all reports of this nature, we get a qualitative assessment by the pilots instead of hard, quantitative data. Without testing weights, power settings, rates of climb, climbing speeds, etc., we get a cloudy picture of the relative performance. If we were Corsair or Hellcat fanbois, we could desperately grasp to a report like this and cry "Look!, the F6F in-game is porked! It says so in this report right here!" Without the context of the test, its only interesting from a historical standpoint; it offers no "proof" of anything.
Hi Gang - been awhile since I've lurked in here ;). Stoney's spot on. Also His advice about thinking about the aerodynamics of climb is very important too. He mentions excess power.
rate of climb = specific excess power = (thrust - drag) / weight * velocity
To illustrate Stoney's point about qualitative vs. quantitative data...
in the sgt pappy's OP we have two data points: rate of climb and airspeed. That leaves thrust, drag, and weight missing from the ROC equation. Without them we don't have any idea what we are evaluating because thrust, drag, and weight also make a big difference on ROC. (Also, don't let the simplicity of the equation fool you. Thrust and drag can be complicated with many factors dynamically influencing their value.)
So in short we have an anecdote of qualitative climb comparisons between an F4U, F6F, and A6M. But you can't really use it to do meaningful comparative analysis and flight model study.
Tango
412th FS Braunco Mustangs
-
This is an interesting equation.
Of course, thrust and drag must take a large amount of analysis to find the net force applied on the plane.
-
Hi Gang - been awhile since I've lurked in here ;). Stoney's spot on. Also His advice about thinking about the aerodynamics of climb is very important too. He mentions excess power.
rate of climb = specific excess power = (thrust - drag) / weight * velocity
To illustrate Stoney's point about qualitative vs. quantitative data...
in the sgt pappy's OP we have two data points: rate of climb and airspeed. That leaves thrust, drag, and weight missing from the ROC equation. Without them we don't have any idea what we are evaluating because thrust, drag, and weight also make a big difference on ROC. (Also, don't let the simplicity of the equation fool you. Thrust and drag can be complicated with many factors dynamically influencing their value.)
So in short we have an anecdote of qualitative climb comparisons between an F4U, F6F, and A6M. But you can't really use it to do meaningful comparative analysis and flight model study.
Tango
412th FS Braunco Mustangs
Tango, skip the FW-190A5/A8 thread, because it will only make your head hurt
-
This is an interesting equation.
Of course, thrust and drag must take a large amount of analysis to find the net force applied on the plane.
Well, you can grab some test data from the E6B to capture an approximate sustained rate of climb. Use that number on one side of the equation and plug in the "weight*velocity" term since they're known. That should give you the "thrust-drag" term. The zero-lift drag coefficients for the F6F and Corsair are known, so you can compute the zero lift drag and add the induced drag and that will give you thrust at that condition, or a fairly close approximation.
As you can see, there's several steps of math here, and a lot of dynamic factors involved. Every time the altitude increases, at least 4 or 5 of the elements in this equation change, so any approximation would only be accurate for a fixed condition. This is why we caution you guys from taking stuff in these flight tests at face value.
-
Tango, skip the FW-190A5/A8 thread, because it will only make your head hurt
42 pages???? :O Lord. Didn't even see it until you pointed it out. I think I'll skip that one ;).
Tango
412th FS Braunco Mustangs
-
42 pages???? :O Lord. Didn't even see it until you pointed it out. I think I'll skip that one ;).
Tango
412th FS Braunco Mustangs
Some epic aero-flymanics in that thread.