Aces High Bulletin Board
General Forums => Aircraft and Vehicles => Topic started by: SgtPappy on February 09, 2008, 06:17:51 PM
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The closest I could get to finding turn performance between certain planes was checking the Y-axis deflection # and the speed on the E6B, but this isn't very accurate compared to the tests others (particularly Widewing and DTango) have been doing. Until I finish my physics course, I'm not going to even attempt the calculations on the turn radius calculation websites concerning AH2.
Is there a way to find the turn radius of an aircraft in-game with just data from the game itself?
Thanks!
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(http://www.badz.pwp.blueyonder.co.uk/Files/Images/RRSimple.jpg)
Hope that helps.
Badboy
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Very good explanation, helped me.
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Thanks Badboy!
Much appreciated.
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I did all the turn tests used on DokGonzo's website http://gonzoville.com/ahcharts/index.php (http://gonzoville.com/ahcharts/index.php) , so I'll throw in a couple of notes for anyone interested in testing....
1) Be sure your tests are at the same altitude or comparisons will be meaningless. A difference of just a couple of hundred feet in altitude will throw off your comparisons. All my testing was done at 500 ft.
2) Keep your circles as level as possible. +/- 50 ft in any one circle was my miniumum on each of three turns. If I went up or down more than that I started over with three more circles. I started over a LOT!
3) The most subjective part of the test is calculating, really guesstimating, your average speed. You will notice that your speed will vary slightly because it will be hard to keep within that +/- 50 ft altitude mentioned above. So you have to take a guesstimate of what your average speed was. You can see that being off just 1 mph in either direction can make a big difference in the size of your radius.
4) How do you know when you've completed an exact circle? Use the .target command to create a target. Start your timing as some part of your cockpit frame crosses the edge of the target, keep it up for three circles and end at the same point.
Divide your total time by 3 to get a one average circle time and use Badboy's formula to calculate your radius.
My formula is different from Badboy's. My formula calculates a slightly smaller radius than his does if I use the numbers he supplied.
I convert speed in MPH to speed in feet/sec (MPH x 1.46), then muliply that by the time to get distance covered in feet, I divide that distance by 3 (since I do three circles) (Circumfrence), then divide that distance by Pi (3.14) to get Diameter, then divide diameter by 2 to get Radius.
Using Badboy's speed and time, my formula calculates a turn radius of:
(170 x 1.46) = 248.2 ft/sec
248.2ft/sec x 18.3sec = 4542.06 ft
4502.06ft / 3.14 = 1446.5 ft (Diameter)
1446.5 / 2 = 723.2 ft Radius
The 2.8 ft difference is irrelevant. It's just the difference each of our formulas use for rounding. His is easier to use, because he's used a constant that takes out a lot of the calculations.
My formula sounds complicated, but since I had to figure it out myself a few years ago and you can see the logic I used, it's what I've got in my spreadsheet which does all the calculating for me automatically.
Warning, once you start testing it can burn up a lot of time. Because then you'll want to test at different fuel loads, different flaps settings, and different weapons configurations.....ect.
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Originally posted by MOSQ
The 2.8 ft difference is irrelevant. It's just the difference each of our formulas use for rounding. His is easier to use, because he's used a constant that takes out a lot of the calculations.
The difference is mostly due to the fact that you are rounding to two decimal places and that you haven't followed the rules for rounding off.
If you use a more accurate conversion factor for converting mph to ft/s it would be 1.46667 to five decimal places, and similarly Pi would be 3.14159 and if you use those numbers in your calculation you would get 726.19ft or 726ft rounded to the nearest whole number, the same value I quoted.
I agree it is a trivial point, but always nice to see errors, no matter how small, correctly attributed.
Badboy
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I'll be sure to update my spreadsheet!
:aok
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Thanks again guys!
Yea, Mosq, it's been taking me FOREVER to make the turn rate tests before I started the thread. Oh wow. When I have time, I'll get to it. If only we could choose to fill up certain fuel tanks at certain levels so I could compare the F4U-1A vs. the F4U-1D more accurately or the Spit9 vs the Spit8.
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Originally posted by SgtPappy
Thanks again guys!
Yea, Mosq, it's been taking me FOREVER to make the turn rate tests before I started the thread. Oh wow. When I have time, I'll get to it. If only we could choose to fill up certain fuel tanks at certain levels so I could compare the F4U-1A vs. the F4U-1D more accurately or the Spit9 vs the Spit8.
I just set the fuelburnrate to max, and manually select tanks to burn them down to the levels I'm looking for.