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Until the late 1950s the fabrics used for aircraft fuselage, wing and/or control surface coverings were invariably woven from natural fibres, linen or cotton in various grades. The fabric was glued, sewn or laced to the wood or metal airframe, soaked with water to initially shrink the skin and remove wrinkles then 'doped' to further tauten, seal and protect it.
Nowadays the natural fiber fabrics are only used in repair or restoration of vintage aircraft and the covering fabrics for recreational aircraft have been adapted from other uses, such as yacht sailcloths and are woven from polyester and glass filament yarns.
For an expanded description of fabrics used today, I recommend the following
site
http://www.auf.asn.au/scratchbuilder/fabrics.html
It covers , in good detail the subjects below and much more:
Fabric Design and Terminology
Polyester Fabric Properties
Chemically Bonded Fabric Covering Process
Coatings
Trade Names for Fabrics and Covering Systems
The following summary was taken from the abstract
referenced in the
http://www.auf.asn.au/scratchbuilder/fabrics.html site:
Design and
Performance Comparison
Daryl Irving Hammond, Oklahoma State University, published in 1999 the results of a study of design and performance properties for selected aircraft fabric covering processes.
The purpose of this study was to examine the design and performance properties of aircraft fabric covering using the Grade-A cotton with Randolph dope, Ceconite with Randolph dope, Cooper Superflite II, Air-Tech Coatings, and Stits Poly-Fiber processes. The design properties studied were characteristics of the base fabric and nonweathered coated material. The performance properties investigated were coating surface changes of gloss and yellowing, strength degradation, and response to heat and flame throughout an accelerated weathering cycle. The hypotheses were written to answer questions about how a selected fabric covering method performs over its intended life and in a variety of functional areas.
There were significant differences in design and performance properties among the five Federal Aviation Administration (FAA) approved covering processes. An investigation of the design properties pointed out differences in elongation, weight, and breaking strength. Ceconite 101 was thicker and stronger, yet stretched more than the other samples. Air-Tech and Superflite processes had higher than average weight per square foot values. An investigation of the performance properties indicated that Superflite and Air-Tech had excellent gloss retention over the accelerated weathering cycle. Ceconite with Randolph dope was the least stable in yellowing degradation while Stits was the best performer. Strength degradation was most pronounced in the Superflite process, decreasing rapidly during weathering. Thermal stress testing showed all processes exhibited heat and flame resistance loss due to weathering. Ceconite with Randolph dope was a volatile combination, bursting into flames with the application of heat, while Air-Tech and Stits resisted sustained burning after ignition. Superflite bum characteristics included emission of thick black acrid smoke. An overall performance index and best performer is provided in the author's research search implications.
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