Film flys on large aircraft

Ft. Worth, TX--Future aircraft may be paintless. But rather than bare metal, subject to corrosion or repeated polishing, or a patch quilt of composite panels, their skin may be protected by plastic films.

A series of flight tests is now underway using an Air Force Reserve C-130 transport. Sections of a new generation of 3M (Minneapolis, MN) polymer film cover about 1,600 ft(super 2) of the forward fuselage. The film is colored to match service camouflage requirements, with large markings applied over it using separate precut appliques. Potential savings to military and commercial users would be in production, maintenance, and coating weight savings upwards of several hundred pounds. Also alleviated are air and water pollution concerns over painting and paint removal operations.

Previous tests with earlier films were mostly on smaller aircraft. The C-130 provides experience more relative to surfaces the size and shape of commercial airliners. A prior 227-hour trial on a C-130 used different films and adhesives, which experienced minor problems from both impact damage and residual adhesive cleanup, as well as wearing away of some of the smaller painted-on stencil markings. The revised polymer and adhesive, and different marking paint, seem to have solved the problems, according to Bill Campbell, Lockheed Martin materials engineering specialist.

The company is interested in paintless methods for use on the Joint Strike Fighter, for which it is a contender. It estimates that for a 3,000 aircraft program, around $3 billion in life-cycle costs may be saved.

Campbell says these savings come from reduction in lifetime rework expenses--stripping the surface for subsequent recovering. Currently, cost of application is about the same for film or paint, since both are labor intensive, he notes. "Also with paint, you need a dedicated hanger with environmental protection for personnel." And when paint is removed, rather than just peeling off a film, surface-blasting media must be contained and disposed of or recycled.

After two years of test data, Campbell says the goal of a six-year lifetime for a film-protected surface seems to be attainable. He adds that currently, C-130s are repainted about every three years, depending on use. In mid-1999, program officials are hoping to cover a small airliner for testing in a commercial environment.