Kitfox Aircraft Stick and Rudder Stein Air Grove Aircraft TCW Technologies Dynon Avionics AeroLED MGL Avionics Leading Edge Airfoils Desser EarthX Batteries Garmin G3X Touch
Results 1 to 6 of 6

Thread: Wiring through the spars.

  1. #1
    Senior Member
    Join Date
    Oct 2009
    Location
    Liberty Lake, WA
    Posts
    205

    Default Wiring through the spars.

    Thought that I saw some photos where some of you drilled holes in the spar to run wiring, where would I find them? I am putting my ADAHRS in my wing and need to run the network cable and the static line into the fuselage. I have the 15 foot network cable so I can't take it to the end of the wing tip and back unless I was to get the 30 foot cable. Any thoughts?
    Stan Inzer
    912 ULS
    Dynon Skyview 10"
    N599KF

  2. #2
    Senior Member SkyPirate's Avatar
    Join Date
    Apr 2009
    Location
    Edgar Springs MO
    Posts
    1,841

    Default Re: Wiring through the spars.

    As a rule you never drill top or bottom on a round spar unless your mounting a strut brace, your filling the hole with a rivet and adding a plate, inside of your spar at the strut mount there is an I beam, if I had to drill a hole on the rear spar it would be on the leading edge close to the strut bracket
    Chase
    Model 5 OutBack
    912 UL

  3. #3
    Senior Member HighWing's Avatar
    Join Date
    May 2009
    Location
    Goodyear, AZ
    Posts
    1,743

    Default Re: Wiring through the spars.

    Quote Originally Posted by SkyPirate View Post
    As a rule you never drill top or bottom on a round spar unless your mounting a strut brace....
    First, I am not an engineer except what I learned as a Dentist - bridge building.

    From what I understand this is typical advice. the stresses on a wing would be tensional stresses and would be the caps - top between root and bracket and bottom bottom outboard of the bracket.

    Quote Originally Posted by SkyPirate View Post
    ...if I had to drill a hole on the rear spar it would be on the leading edge close to the strut bracket
    I might have a little different thought on this one. The greatest point of stress on the spar of a strut designed wing would be at the strut attach bracket. I think I would go inboard or outboard of that. I do know that in the Model IV book, the spar was drilled to pass the pitot tube tubing and it was outboard of the attach bracket about a foot.

    Again, this is just from an amateur.
    Lowell Fitt
    Goodyear, AZ


    My You Tube Channel

  4. #4
    Senior Member SkyPirate's Avatar
    Join Date
    Apr 2009
    Location
    Edgar Springs MO
    Posts
    1,841

    Default Re: Wiring through the spars.

    Yes when I said near the strut bracket I should have been more clear, "close" = inboard , your between the main strut and jury strut and with in the area of the inner I beams added strength
    Chase
    Model 5 OutBack
    912 UL

  5. #5
    Senior Member jiott's Avatar
    Join Date
    Jun 2010
    Location
    Portland, OR
    Posts
    2,959

    Default Re: Wiring through the spars.

    Personally I wouldn't drill holes in the spar anywhere except on the extreme ends (and I am a mechanical engineer). I know several guys who ran wiring and even pitot tubing outside the spars and were able to snake it around the ribs and fuel tank (on model 7). I believe this is a better method if you can't run it inside the full length of the spar.
    Jim Ott
    Portland, OR
    Kitfox SS7 flying
    Rotax 912ULS

  6. #6
    Senior Member Dave S's Avatar
    Join Date
    Oct 2008
    Location
    St Paul, MN
    Posts
    1,833

    Default Re: Wiring through the spars.

    I did the same as Jiott mentioned....ran wires & pitot plumbing behind the fuel tank on our 7 just ahead of the rear spar & snake through the ribs & secured with a compatible adhesive...a service loop of the wires at the inboard end of the wings made an easy design for folding the wings (attached).

    The skystar build manual for the 7 said to drill a hole in the spar for the tube running to the pitot.....I could not bring myself to drill a hole the spar...not an enginer either but lots of experience with metal & fabrication of stuff.

    Sincerely,

    Dave S
    KF7 Trigear
    912uls warp drive
    Attached Images Attached Images

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •