Hummingbird Posted June 6, 2020 Posted June 6, 2020 (edited) Since a bug report on this was requested, here it is. I'm suspecting an incorrect Clmax is used for the FW190 in DCS due to Fw190's oddly low turn performance compared with the P-51 (& now P-47) ingame. I base this on NACA report TN 1044, 824 & 829 as well comparative trials between the F4U (which uses the same airfoil as the Fw190), Fw190 and the P-51B. Let's start off with NACA report TN 1044, below are the numbers summarized Link to full report: https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19930084610.pdf NACA 23XXX (F6F, Fw190 etc) results: FT high alt / FT low alt M 0.30 = -- / -- M 0.35 = 1.35 / -- M 0.40 = 1.28 / -- M 0.45 = 1.16 / -- M 0.50 = 1.02 / -- NACA 00XX (P-39 etc) results: FT high alt / FT low alt M 0.30 = 1.20 / 1.24 M 0.35 = 1.12 / 1.18 M 0.40 = 1.05 / 1.14 M 0.45 = 0.97 / 1.08 M 0.50 = 0.92 / -- NACA 66-XXX (P-51, Tempest etc) results: FT high alt / FT low alt M 0.30 = 1.12 / 1.23 M 0.35 = 1.07 / 1.16 M 0.40 = 1.05 / 1.19 (2nd peak low alt) M 0.45 = 1.02 / -- M 0.50 = 1.05 / -- (2nd peak high alt) To summarize these figures show a 0.28 - 0.14 difference in Clmax between the F4U/F6F/Fw190's wing and the P-51's at high alt between 0.35 & 0.45 mach. At low altitude there reason to believe the difference would be even greater as NACA report 829 https://ntrs.nasa.gov/search.jsp?R=19930091906 shows a Clmax of 1.55-1.60 for the F6F. Very similar to the 1.58 reported in a document from Focke Wulf AG https://i.imgur.com/SPf4kiA.jpg In practice such a difference in Clmax should make up for the Fw190's disadvantage in wing loading compared with the P-51, enabling it to match the P-51 in turns, which is also what the British AFDU tactical trials hinted at when they paired a Fw190G vs a P-51B at relatively high alt, where the BMW engine doesn't really perform, and yet little difference was found between the two in turning. Qoute: "Turning circle 42. Again there is not much to choose. The Mustang is slightly better. When evading an enemy aircraft with a steep turn, a pilot will always out-turn the attacking aircraft initially because of the difference in speeds. It is therefore still a worthwhile manoeuver with the Mustang III when attacked." For further confirmation of the airfoil data comparative trials between the F4U-1 & P-51 saw the F4U easily beat the P-51B in turning, despite the F4U having a slightly higher wing loading: http://www.wwiiaircraftperformance.org/f4u/p-51b-f4u-1-navycomp.pdf Qoute: "each plane was loaded to it own specified full fighter load, 9,100 lbs. for the P-51B, and 12,162 lbs. for the F4U's" "© The F4U-1 is everywhere superior in maneuverability and response." Once again the F4U uses the same NACA 23015 to 23009 airfoil selection as the Fw190 & F6F. Hence I would like to report the Fw190 & P-51's use of a similar Clmax (I believe 1.35 for both has been stated) in DCS as a bug. Edited June 7, 2020 by Hummingbird Updated the document links so they work
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