Aces High Bulletin Board
General Forums => Aircraft and Vehicles => Topic started by: Nimrod45 on September 08, 2007, 10:12:36 AM
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Why is there no speed or climb data for this bird, is it eqaul to the D-Hog or closer to the F4U-1?
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You can get the data in the Hanger view.
Right click the plane name in the list and select "Speed Chart" or "Climb Chart".
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Can't get it on the home page though?
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The F4U-1A is slightly faster than the -1, and climbs and accelerates roughly equivalent to the 1D.
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I've always wondered but never knew a reliable way of testing but I have a few questions....
1) If the A-Hog is flying around with a bomb shackle (no bomb), does it end up turning as well as the D-Hog?
2) Also, how badly do the empty rocket tabs affect the D-Hog's turning?
3) And finally, is it just me or does the F4U-4 seem to handle a tad worse that the other Hogs? When my buddies and I flew around in H2H, I flew against them in F4U's to see which one I would prefer best, and the 4-Hog, (though one of my favourites) was able to beat them the most often, but it seemed to high AoA stall a little more; i.e. flop over on one wing during a turn at low-med speeds.
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The bomb shackles and rocket tabs by themselves aren't going to affect turning all that much that I've noticed so long as you've cut the ordinance loose (then again, I never take eggs up in the 1A, and have so far never needed to haul a drop tank on it outside of the Rabaul Snapshot). The bomb shackles in the 1A, and rocket tabs in the 1C/D/4 WILL add drag that will affect your top speed.
I haven't noticed the F4U-4 being more prone to wing drop while maneuvering at the low end. Then again, there's some people that insist the F4U-1 is less likely to depart than the other models, even though the -1 didn't have the stall strip so should actually be LESS stable.
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I have a hard time believing that it's climb rate and acceleration were not better than it is on AH, I wonder what info they used in building the flight model. All reports that I have ever read indicate it was an unstable race horse compaired to the extremely tame predictable Hellcat but in the game the only thing it has on the Hellcat is top end speed.
I already know, SEARCH BUTTON.
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Yeah, the search is a smart idea lol.
There are quite a few threads that have talked about the weirdness concerning the Hog's stability in relation to the Hellcat's.
Last question (And yes, I do use the search bar as well). I stumbled across FAA tests of the Corsair Mk. II, III, and IV on F4U performance trials (http://www.wwiiaircraftperformance.org/f4u/f4u.html) and the highest figure the FAA could achieve with these Hogs (which are said to have been tested with the R-2800-8W) was 405 mph as opposed to the US tests of 425 mph. Is this because of the lower-grade British fuel? But if so, why do the climb rates seem the same to the US figures?
You can find the tests at the bottom of the page I highlighted.
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Thanks that is some pretty cool info.
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Lol of course it is. But that doesn't answer the question :p
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Could be any number of reasons, really.
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So did the 130 grade and 100 grade fuel differ much? I.e. would any of the high performance fighters suffer from switching from 130 to 100?
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I really wouldn't know but I would assume that there would deffinatly be a noticable difference.
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One of the well-educated people at WWII Aircraft Forum Site (http://www.ww2aircraft.net) stated that higher grades prevent engine knocking. Not sure of that concept, or how it helps the engine and performance, but she/he stated that the operational limits of the two fuel grades were not different at all and that the performance gain was not too different.
Power settings are said to be the same for both grades.
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Some new things I've learned.
Apparently the higher grade fuel does increase boost pressure, but of course at low altitudes where the supercharger allows. I've read that, in a Merlin for example, that 61" of boost was gained from 100 octane while 130 gave a boost of 67".
Now I'm just trying to find out about the R-2800-8W and about how much that extra boost increases performance.
Also, what's the fuel grade we use here in AHII?
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Originally posted by SgtPappy
Some new things I've learned.
Apparently the higher grade fuel does increase boost pressure, but of course at low altitudes where the supercharger allows. I've read that, in a Merlin for example, that 61" of boost was gained from 100 octane while 130 gave a boost of 67".
Now I'm just trying to find out about the R-2800-8W and about how much that extra boost increases performance.
Also, what's the fuel grade we use here in AHII?
Don't know, I wonder if the even modeled such a thing.
And maybe there was only a speed difference between the Brit and American test at certain altitudes.
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It ABSOLUTELY makes a difference.
AVGAS is rated by grade according to the amount of tetraethyl lead it contains and is dyed to identify the grade. Shortly after WW2 before hairdryers became so important, there were 5 grades of AVGAS: red 80/87 octane, blue 91/98 octane, green 100/130 performance, brown 108/135 performance, and purple 115/145 performance.
With the tremendous decrease in AVGAS requirements, the 108/135 and 115/145 for big bore engines and 91/98 for smaller engines were discontinued. The TEL content for 100/130 gas was decreased from 4.0 to 2.0 milliliters per gallon, and this low lead fuel is now what we have as 100LL.
What the designations meant was the following: the first number was the octane, or performance rating of the fuel with a lean mixture. So 115/145: 115 would be the lean mixture rating. 145 would then be the rich mixture such as used for takeoff. Additionally, those numbers showcased the fuels anti-detonation properties.
What that means in plain english is you would not get the maximum rated power in a big bore radial at takeoff power with 100LL, in fact you would more likely then not be detonating away all the way down the runway. R2800s are poisioned by 100LL at high power settings, which is why many of them are limited to 52" manifold pressure using todays fuel, except perhaps while running on a race mix at the Reno Races.
Bodhi could probably fill in the gaps on what engines like best, but that is the summary of it. Bottom line, engines 60 years ago require the higher TEL content. In fact, the higher test fuels, 115/145 for instance had a lot of aromatics such as benzine, toluene and xylene to increase its anti detonation characteristics. What was found later down the line is these additives attacked rubber products in the fuel system. As time wore on and 100LL was the fuel, materials were developed that were not susceptible to aromatic compound deterioration.
Wolf