What identification marking is found on the selvage edge, and in which direction is the warp applied?

• A. The FAA-PMA stamp is found on the selvage edge and the warp is applied parallel to the line of flight
• B. The stamp is on the center; Warp perpendicular to line of flight
• C. The stamp is on the underside; Warp is 45 degrees
• D. No markings exist on the selvage edge

Answer: (A)

The identification that matters here is that the selvage edge carries the FAA-PMA stamp, and the fabric’s warp is oriented parallel to the line of flight. The selvage edge is where manufacturer and approval markings are placed so the material can be traced and verified as PMA-approved for use on certified aircraft. Aligning the warp parallel to the line of flight means the primary lengthwise fibers run in the same direction as the aircraft’s forward motion, matching the main tensile loads experienced during flight and ensuring the fabric’s strength is utilized where it matters most. The other possibilities don’t reflect common practice: marks aren’t typically centered or on the underside, and markings are generally present to indicate PMA approval.