Seat rail maintenence

Discussion in 'Maintenance Bay' started by sarangan, Apr 11, 2019.

  1. sarangan

    sarangan Pre-takeoff checklist

    Joined:
    Jun 7, 2008
    Messages:
    486
    Location:
    Dayton, OH
    Display Name:

    Display name:
    Andrew Sarangan, CFII
    This might be a naiive question, but is seat rail inspection part of an annual? I have studied the mechanism under the seats, and it appears to be far less beefy than the one under my car seat. The reason I ask is, a seat rail becoming disengaged could cause a serious issue, even catastrophic, especially during takeoff. Has this ever happened, and how reliable are the seat locking mechanisms in GA aircraft?
     
  2. asicer

    asicer En-Route

    Joined:
    Jan 1, 2015
    Messages:
    3,481
    Display Name:

    Display name:
    asicer
    I'd trust the seat rail in a DA40 no problem :)
     
    dans2992 likes this.
  3. Dan Thomas

    Dan Thomas Final Approach

    Joined:
    Jun 16, 2008
    Messages:
    5,175
    Display Name:

    Display name:
    Dan Thomas
    What airplane are we talking about?
     
  4. Kenny Phillips

    Kenny Phillips Pattern Altitude

    Joined:
    Jul 29, 2018
    Messages:
    1,680
    Display Name:

    Display name:
    Kenny Phillips
    Heck yeah it's happened. There are airworthiness directives (ADs) on this very subject on Cessna aircraft.
     
    Omalley1537 likes this.
  5. baboss

    baboss Pre-takeoff checklist

    Joined:
    Apr 20, 2012
    Messages:
    196
    Location:
    Central IL
    Display Name:

    Display name:
    Brock Boss
    Here's where we cover the seat/seat rail inspection during our annual. But since we've got a Cessna the AD has it covered as well.

    Title 14: Aeronautics and Space
    PART 43—MAINTENANCE, PREVENTIVE MAINTENANCE, REBUILDING, AND ALTERATION
    Appendix D to Part 43—Scope and Detail of Items (as Applicable to the Particular Aircraft) To Be Included in Annual and 100-Hour Inspections
    (c) Each person performing an annual or 100-hour inspection shall inspect (where applicable) the following components of the cabin and cockpit group:
    (2) Seats and safety belts—for poor condition and apparent defects.
     
  6. sarangan

    sarangan Pre-takeoff checklist

    Joined:
    Jun 7, 2008
    Messages:
    486
    Location:
    Dayton, OH
    Display Name:

    Display name:
    Andrew Sarangan, CFII
    Good point. I was talking about Cessnas and Pipers where you pull a lever to move the seat on a rail.
     
  7. Sinistar

    Sinistar Pattern Altitude

    Joined:
    Sep 9, 2016
    Messages:
    1,706
    Display Name:

    Display name:
    Brad
    In our 182 the seat rail inspection is mandatory 100hrs but we rarely hit 100hrs before the annual so its done during the annual.
     
  8. Clip4

    Clip4 En-Route

    Joined:
    Jun 27, 2013
    Messages:
    3,885
    Location:
    A Rubber Room
    Display Name:

    Display name:
    Cli4ord
    The seats are removed as part of the annual inspection. Your IA should be inspecting the seat and the rails.
     
  9. Tom-D

    Tom-D Taxi to Parking PoA Supporter

    Joined:
    Feb 23, 2005
    Messages:
    31,184
    Display Name:

    Display name:
    Tom-D
  10. Gary Austin

    Gary Austin Pre-Flight

    Joined:
    Sep 15, 2017
    Messages:
    75
    Display Name:

    Display name:
    Gary
    Tom, that covers it well, 100 hours or 12 months, whichever comes first, I always put that in the maintenance record, also it's not just the seat and rail, well it is the seat, but it's a bunch around the seat, tang, amount of wear and distance between tangs, rollers, it pays to read that AD well, Cessna states no lubrication, Piper said lubricate rails, thanks for the site
     
  11. Dan Thomas

    Dan Thomas Final Approach

    Joined:
    Jun 16, 2008
    Messages:
    5,175
    Display Name:

    Display name:
    Dan Thomas
    The AD forbids lubricating the rollers and bushings, since it just accumulates dirt and forms sludge that eventually seize the rollers. In Cessna's service manuals they tell you that you can rub paraffin (wax) on the seat rails to let the roller housing slide easier, and believe me, that works really well and doesn't attract dust. It will need renewing avery 50 hours or so. It helps prevent galling between the aluminum rail and aluminum roller housings, of which those tangs are a part. Worn tangs mean new roller housings, and they're not cheap.

    Don't put the paraffin on the top of the rail where the roller runs. Just along the side edges and under the rail, the places that the housing rubs.
     
  12. Tom-D

    Tom-D Taxi to Parking PoA Supporter

    Joined:
    Feb 23, 2005
    Messages:
    31,184
    Display Name:

    Display name:
    Tom-D
    You'd be surprised how well dry slide works.
     
  13. Silvaire

    Silvaire En-Route

    Joined:
    Oct 10, 2012
    Messages:
    3,685
    Display Name:

    Display name:
    Silvaire
    The Cessna seat rail issue is due to a couple of things. First off is you have to adjust the seat every time you get in or out of it. Second is the whole mechanism for retracting the pin isn’t the greatest engineering feat ever accomplished and doesn’t work that well a lot of the time. Maybe it gets worn or out of adjustment or just isn’t operated correctly but the result is the pin doesn’t get pulled completely out and you jimmy the seat with your weight so it gets pushed out by the rail and eventually the hole gets enlarged and eroded and the cracks form at the edges and it all goes south from there. You end up with a 25 page AD that has been superseded half a dozen times and just keeps getting longer.
     
  14. bluerooster

    bluerooster Pattern Altitude

    Joined:
    Nov 28, 2011
    Messages:
    1,529
    Display Name:

    Display name:
    shorty
    As to Piper, what I found on the rails in my Cherokee was kinda spooky to say the least. seat track (4).JPG seat track (3).JPG