- What determines the required quality & strength of fabric that is to be used for covering aircraft?
Determined by pound per square foot of wing loading (PSF) & the never exceed speed of the aircraft (VNE)
- When are anti-tear strips recommended & where are they used?
Under wing rib stitching when VNE is greater than 250
- What is the maximum permissible deterioration of aircraft fabric before it is considered unairworthy?
More than 30% from original tensile strength
- What should be the strength of the fabric used for re-covering an aircraft?
High grade aircraft tensile material, equivalent to the original strength from original manufacturer
- What is the purpose & location of drain grommets in aircraft fabric?
Allows condensed moisture to leave the aircraft as well as ventilation
located underside of airfoils trailing edge close to ribs
- How are drain grommets installed in aircraft fabric?
Brass grommets mounted to fabric patches then doped to coverings
Plastic grommets are doped directly to coverings
Both require 2nd coat of dope
- Name the methods of applying fabric to an aircraft wing?
Blanket & envelope method
- What is the purpose of reinforcing tape?
Used under all stitching, prevents stitching ford from tearing through fabric
- What type of fabric is not affected by moisture or mildew?
- What methods are used to check the strength of doped fabric?
Fabric punch test if fails then a laboratory test
- What type of machine-sewed seems are used in aircraft coverings?
Plain overlap seams
Folded fell seams
French fell seams
- What should be done with structure that will come in contact with doped fabric?
Treat all parts of the structure
- If the original rib stitch spacing cannot be determined when re-covering and aircraft, where can you find the rib stitch spacing that should be used?
- What is the standard tie off knot used during rib stitching?
Modified seine knot
- What do you call the edge cloth, tape, or webbing that has been woven to prevent raveling?
- The type of fabric used for covering aircraft are organic & synthetic. Name two organic and two synthetic types.
Organic fibers - cotton & linen
Synthetic fibers - fiberglass & nylon
- When covering aircraft, where is surface tape used?
Sewed seams, lapped edges, & all stitching
- Name the advantages of using the envelope method to cover fabric aircraft.
Saves labor most sewing is done by machine
- How are wrinkles removed from cotton fabric?
Wetting the wrinkles & allowing to dry
- When is finishing tape applied?
After the second coat of dope is dry, and the nap has been sanded away
- How wide should surface tape be when used to cover the trailering edge of an aircraft wing?
- What is the recommended type of repair for an L shaped tear when the legs are more than 14 inches long?
A doped on patch, if VNE is less than 150mph