INDUSTRIAL FOAM TECHNOLOGY CARGO LINER HISTORY...EARLY ON
Probably the first materials used for lining baggage compartments was ABS sheet, aluminum and plywood. These materials of choice had many drawbacks, including rigidity and weight. But the early aircraft builders had other considerations to contend with and cargo lining material was not high on their list of priorities. We don't know whose idea it was to use fiberglass reinforced plastic (frp) for cargo liner but it was a major breakthrough and a definite improvement over the aforementioned materials. The original frp products represented a quantum leap in cargo liner quality and performance but they possessed fewer than half of the desired characteristics common to today's materials. They did have low specific gravity, good corrosion resistance, satisfactory flame resistance, repairability, good aging properties, and dent and fatigue resistance, but they were a far cry from the liners available today, which are 50% lighter than the early liners. With Larger Piston Aircraft With the advent of the larger four-engine piston driven aircraft such as the DC-6 and DC-7, improvements in basic properties were required.-Mechanical properties were upgraded by the use of satin weave fabrics and bolted joint pullout resistance at the edges was increased. Pigments were added to the resin systems to obtain a uniform white color throughout, wide sizes (48" x 60") became standard and much of the surface porosity was reduced so that the sheet possessed greater integrity. Thickness was often the answer to increased puncture resistance, and although thicker meant heavier, weight was not as critical as it is now. Gillfab(r) 1018, qualified to Douglas specification 10011 (now obsolete) is a liner that was representative of the era, although sales of that product have evaporated in recent years. Vast improvements in the newer liners have accounted for those decreases -- for example, in the last three years sales of 1018 have totaled less than 20 sheets. With the Advent of the Jet Age The introduction of jet aircraft to commercial aviation focused attention on weight and improved puncture resistance. Test fixtures were developed to empirically ascertain comparative values expressed in foot-pounds. Each airframe manufacturer designed its own impact tester, creating confusion when attempts were made to correlate data. Liners of the last of the piston aircraft and early jets were upgraded by advances in resin technology, proprietary additives, special cloth weaves, and better processing techniques. The advances resulted in improved puncture resistance, reduced weight, better flame self-extinguishing properties, and resistance to shear -- all of which combined to greatly prolong service life. The trijets became increasingly popular, cargo liner weight became more and more critical. Material requirements were met by higher performance reinforcing agents. The goal was to provide a better liner that weighed less, and to improve the following characteristics: abrasion and shear resistance; rigidity for better appearance; flame resistance; and puncture resistance. Also, surface blemishes and porosities were eliminated. Gilliner 1166, 1266, and 1366 met almost all the desirable characteristics and represented almost 30 years of concerted effort and specialization in the field.

For more information, contact M. C. Gill Corporation, 4056 Easy St., El Monte, CA 91731, 626-443-4022, FAX 626-350-5880.