Avidflyer2
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I am bothered by the many posts on replacing of seat slings by Owner/Operators. First allow me to cite a few FAA rules to be followed by other considerations. Meanwhile sharpen your pitchforks as I’m sure there will be naysayers and dissension amongst this group!
FAA Part 43, Appendix A delineates who may perform Preventative Maintenance, Maintenance, and Major Repairs or Major Alterations. It even goes on to say that an Owner or Operator must hold at least a Private Pilot Certificate to perform Preventative Maintenance (abbreviate as PM). A Solo student therefore is not an operator entitled to exercise this privilege to perform PM.
Under the part for Major Repairs any repair to the seat frame or seat frame primary structure is a Major Repair. An example here would be cutting off the tabs for attaching the seat springs, or welding up the holes left by removing the springs. Removing the seat springs is an alteration which can be construed as a Major Alteration as it affects the original design. Both the Major Repair and Major Alteration thoughts should be kept in mind if the seat frames never had a seat sling, or the previous seat sling was not documented on a Form 337.
Using Ceconite as a seat sling has become an accepted practice only when the fabric is installed per the manufacturers instructions or in accordance with an STC. For example an adhesive seam is supposed to overlap a minimum of two inches. Another is that the recommended adhesive be used and applied to completely fill the warp and weave of the fabric. Afterwards the Ceconite is to be heat shrunk for it to reach its full strength. The raw Ceconite is a thermosetting plastic that will continue to stretch until it is heated to the proper temp, afterwards the material is “set” and will not stretch.
Don’t use any ordinary contact cement like Weldwood Contact Cement. Use a recognized aviation product like Poly-Tac which is made specifically for the Ceconite to metal adhesion joint.
Yes the Owner/Operator may repair or replace upholstery as PM but I think the seat sling in particular demands a sign off by an A&P mechanic. Contact your local FSDO for their ruling if in doubt.
FAA Part 43, Appendix A delineates who may perform Preventative Maintenance, Maintenance, and Major Repairs or Major Alterations. It even goes on to say that an Owner or Operator must hold at least a Private Pilot Certificate to perform Preventative Maintenance (abbreviate as PM). A Solo student therefore is not an operator entitled to exercise this privilege to perform PM.
Under the part for Major Repairs any repair to the seat frame or seat frame primary structure is a Major Repair. An example here would be cutting off the tabs for attaching the seat springs, or welding up the holes left by removing the springs. Removing the seat springs is an alteration which can be construed as a Major Alteration as it affects the original design. Both the Major Repair and Major Alteration thoughts should be kept in mind if the seat frames never had a seat sling, or the previous seat sling was not documented on a Form 337.
Using Ceconite as a seat sling has become an accepted practice only when the fabric is installed per the manufacturers instructions or in accordance with an STC. For example an adhesive seam is supposed to overlap a minimum of two inches. Another is that the recommended adhesive be used and applied to completely fill the warp and weave of the fabric. Afterwards the Ceconite is to be heat shrunk for it to reach its full strength. The raw Ceconite is a thermosetting plastic that will continue to stretch until it is heated to the proper temp, afterwards the material is “set” and will not stretch.
Don’t use any ordinary contact cement like Weldwood Contact Cement. Use a recognized aviation product like Poly-Tac which is made specifically for the Ceconite to metal adhesion joint.
Yes the Owner/Operator may repair or replace upholstery as PM but I think the seat sling in particular demands a sign off by an A&P mechanic. Contact your local FSDO for their ruling if in doubt.
