whartsell Posted July 15, 2013 Posted July 15, 2013 In doing some flight planning with your wonder app I noticed one discrepancy. The drag indexes seem to be wrong for a few weapons. For example in your planned 3xAGM-65 have a drag index of 2.96 but according to TO-1A-10A1-A-10A Chart A1-7 you get: 3xAGM-65: .35 x 3 = 1.05 1xLAU-88A: .61 x 1 = 0.61 total:1.66 I have noticed that the values in your app are different for the AN/ALQ-131 as well. do you have a source for your drag index data other than the -1-1? Arduino,EOS and Helios Tutorial Static ATC menu mod
PFunk1606688187 Posted July 15, 2013 Posted July 15, 2013 In doing some flight planning with your wonder app I noticed one discrepancy. The drag indexes seem to be wrong for a few weapons. For example in your planned 3xAGM-65 have a drag index of 2.96 but according to TO-1A-10A1-A-10A Chart A1-7 you get: 3xAGM-65: .35 x 3 = 1.05 1xLAU-88A: .61 x 1 = 0.61 total:1.66 I have noticed that the values in your app are different for the AN/ALQ-131 as well. do you have a source for your drag index data other than the -1-1? I think the A-10A numbers are long since obsolete. We're talking late 80s. Those who have access to the updated A-10C documents can confirm this. Any different numbers are probably sourced from something with more up to date authority than a declassified document from before Desert Storm. Warning: Nothing I say is automatically correct, even if I think it is.
whartsell Posted July 15, 2013 Posted July 15, 2013 That's why I asked the source of the discrepancy. I doubt the aerodynamic properties of the agm65 changed since the 80s. If drag indexes changed it would have to be the result of a whole new flight test regime with a new 0 drag index based baseline. Considering some ordinance have different values and some do not I doubt that's the case. Just because a manual is old doesn't mean the data is obsolete. Design changes cause obsolescence not age. Arduino,EOS and Helios Tutorial Static ATC menu mod
Eddie Posted July 15, 2013 Posted July 15, 2013 The drag index values used in these tools were provided by me and are straight from the A-10C 1-1. And yes, things like drag index values do change as new/more accurate tests take place over time, as well as changes to weapons and suspension equipment. The drag index value of 2.96 as provided by this tool is indeed correct, your value obtained using (very) old documents is not. To further complicate matters many weapons have different drag index values depending on which weapon station they are carried. Although as this is not modelled in DCS at present I didn't give these values to Balu.
whartsell Posted July 15, 2013 Posted July 15, 2013 I stand corrected. I did some research and found your earlier posts. I didn't think about updated data in interference drag on the stations. One discrepancy I still see is with regards to 2 aim9ms on station calculated with your numbers vs the app. Arduino,EOS and Helios Tutorial Static ATC menu mod
whartsell Posted July 15, 2013 Posted July 15, 2013 One more thing. I'm not trying to be too pickey. I am not primarily concerned with reality vs the sim. If the sim uses x value regardless of the authenticity of said x I'm ok using that. Arduino,EOS and Helios Tutorial Static ATC menu mod
Eddie Posted July 15, 2013 Posted July 15, 2013 It should be 1.03 for 2 AIM-9M/CATM-9. 2* 0.4 for the missiles themselves, 0.19 for the DRA, and 2*0.02 for the LAU-105s. If the app does not turn out those values then it is off. I don't have, or use, the program so haven't checked.
Eddie Posted July 15, 2013 Posted July 15, 2013 One more thing. I'm not trying to be too pickey. I am not primarily concerned with reality vs the sim. If the sim uses x value regardless of the authenticity of said x I'm ok using that. The sim drag index values are a bit bizarre to say the least, frankly I can't make head nor tails of them or how ED have modelled them. Suffice to say they do not match reality, but that said using the real drag index numbers for performance calculations, or to give a sense of how appropriate your config is works fine in the sim.
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