P47D x FW190

Discussion in 'Engineering Retrospective' started by _strafe_, May 26, 2007.

  1. HoHun

    HoHun FH Beta Tester

    Joined:
    Sep 22, 2001
    Messages:
    2,643
    Re: P47 x FW190

    Hi again,

    >The current turn rate of the P-47D (1 km, WEP, 100% fuel) is too high. I tested it in 1.64R2 and got a sustained turn circle time of 23.2 s. At 14500 lbs weight, that yields a clmax of 1.55. I don't have real life data, but as a thin high-speed wing, it should be good for perhaps 1.20 only. That would yield a circle time of 25.7 s.

    From airfoil coordinate data for the Seversky S-3 airfoil used for most Kartveli designs - including the P-47 -, I calculated an airfoil lift-over-drag polar using Javafoil.

    Here is the graphical output from Javafoil:

    http://hometown.aol.de/WBHoHun/Namenlos.png

    Note that the Javafoil output is not completely reliable and changes according to the parameters and the calculation models used, so my Javafoil data doesn't prove anything.

    However, it delivers a Clmax figure of about 1.2, which matches my expectations - and which as far as I can tell Freehost surpassed by far in 1.64R2, yielding much better manoeuvrability for the P-47 than I would expect.

    Regards,

    Henning (HoHun)
     
  2. HoHun

    HoHun FH Beta Tester

    Joined:
    Sep 22, 2001
    Messages:
    2,643
    Re: P47 x FW190

    Hi again,

    >From airfoil coordinate data for the Seversky S-3 airfoil used for most Kartveli designs - including the P-47 -, I calculated an airfoil lift-over-drag polar using Javafoil.

    Somehow, it's hard to find data on the Seversky S-3. NACA Report TR 829 has a lift curve for a P-35 (as "Airplane 8"), which is supposedly equipped with this wing. In clean condition with propeller removed to avoid slipstream-induced errors, the Clmax measured on that P-35 is about 1.16.

    However, the NACA report states that the P-35 used NACA 0015/NACA 0009 sections, which is rather confusing since historical photographs show clearly that the P-35 had a cambered section. (The Seversky S-3, of course.)

    Regards,

    Henning (HoHun)
     
  3. Jochen

    Jochen Well-Known Member

    Joined:
    Nov 12, 2001
    Messages:
    215
    :eek:

    Regards,

    Jochen