Aerodynamical proparties of P-51 horizontal stabilizer

Discussion in 'Technical Requests' started by finfly, Nov 7, 2011.

  1. finfly

    finfly New Member

    Joined:
    Nov 7, 2011
    Messages:
    4
    Likes Received:
    0
    Trophy Points:
    1
    #1 finfly, Nov 7, 2011
    Last edited: Nov 8, 2011
    I'm doing a school project about P-51 tail. My task is to calculate if possible shear force and bending moment distribution's of P-51 horizontal stabilizer. Currently I'm stuck looking for info really old NACA files. Has anyone info about horizontal stabilizer lift coefficient and mass distribution of the horizontal stabilizer wing box? Thanks in advance!
     
  2. FLYBOYJ

    FLYBOYJ "THE GREAT GAZOO"
    Staff Member Moderator

    Joined:
    Apr 9, 2005
    Messages:
    23,207
    Likes Received:
    790
    Trophy Points:
    113
    Gender:
    Male
    Occupation:
    Aircraft Maintenance Manager/ Flight Instructor
    Location:
    Colorado, USA
    Sounds like a fun project but a suggestion if I may - why don't choose a newer airframe. You might be lucky and find that data but most of the time data like like, especially for WW2 aircraft is long gone. If anyone can help you "Dragondog" might have informtion.
     
  3. finfly

    finfly New Member

    Joined:
    Nov 7, 2011
    Messages:
    4
    Likes Received:
    0
    Trophy Points:
    1
    #3 finfly, Nov 7, 2011
    Last edited: Nov 7, 2011
    Probably so but our project is more in the structural side of aeronautical engineering so it is not critical to get real values. It's more important to have info about materials and structures right. And those bits are much easier to find for P51 than for more modern planes that have some commercial value. Doing those calculations with correct values would ad nice touch (and hopefully rise in the grate).

    Plus P51 is really cool and worth of the extra effort when everybody else studies A320's!
     
  4. FLYBOYJ

    FLYBOYJ "THE GREAT GAZOO"
    Staff Member Moderator

    Joined:
    Apr 9, 2005
    Messages:
    23,207
    Likes Received:
    790
    Trophy Points:
    113
    Gender:
    Male
    Occupation:
    Aircraft Maintenance Manager/ Flight Instructor
    Location:
    Colorado, USA
    You might be able to find some information within the P-51 structural repair manual. There may be one on this site in the technical section.
     
  5. finfly

    finfly New Member

    Joined:
    Nov 7, 2011
    Messages:
    4
    Likes Received:
    0
    Trophy Points:
    1
    Thanks. It and the part list for P51 are the best sources for our work.
     
  6. kettbo

    kettbo Member

    Joined:
    Oct 18, 2007
    Messages:
    435
    Likes Received:
    14
    Trophy Points:
    18
    Occupation:
    US Army (Ret)
    Location:
    Western Washington, USA
    I can get you in contact with Boeing's Historian. He may be able to point you in the right direction.
    Mike's personal library is formidable....await seeing what treasures he has at the office.
    Keep posting here but shoot me a PM as a reminder.
     
  7. finfly

    finfly New Member

    Joined:
    Nov 7, 2011
    Messages:
    4
    Likes Received:
    0
    Trophy Points:
    1
    That would really take our project to a new level. Thanks George!
     
  8. drgondog

    drgondog Well-Known Member

    Joined:
    Jun 28, 2006
    Messages:
    7,359
    Likes Received:
    561
    Trophy Points:
    113
    Gender:
    Male
    Occupation:
    Executive, Consulting
    Location:
    Scurry, Texas
    I'm away from my reference drawings on the 51 (I assume B/C/D vs H) but here are some thoughts. Sorry I'm late on this.

    1. To get a mass distribution you really need detail drawings IMO with a BOM explosion to get a sense of skin thickness, rib geometry, spar geometry, etc
    2. To get the aero loads you have two questions primarily. A.) what is the flight profile of interest? Somewhere in the pullout process of a steep dive?, and B) what is the downwash component over the Horizontal Stab at peak aero load?
    3. The pre-metal elevator models of the B/C/D had a -2degree incidence, while the metal elevator version had 1/2 degree. These distinctions are of course necessary to include in downwash estimation to get a relative AoA (and hence CL) for the max lift force at the Aerodynamic center.

    The CL of the stabilizer will be correct for the NACA airfoil - wing or Elevator (or Rudder) makes no difference - BUT the elevator deflection angle will create a cambered airfoil with associated changes to be considered for CL at your calculated relative AoA.

    Good Luck.

    Bill
     
  9. drgondog

    drgondog Well-Known Member

    Joined:
    Jun 28, 2006
    Messages:
    7,359
    Likes Received:
    561
    Trophy Points:
    113
    Gender:
    Male
    Occupation:
    Executive, Consulting
    Location:
    Scurry, Texas
    My 'Dean's 1000' is around here somewhere. It probably has some NACA info regarding the Stab.

    Thinking more about Mass distribution, I would look at the plan view and front elevation to get a sense of the tapers and and assume the mass distribution is proportional to the geometry. My best guess is that the center of mass is at Approximately 38-40% of the chord (calculated from CL) and that the lift vector should be translated to ~ 25% chord for bending moment calcs.
     
Loading...

Share This Page