Monday, September 1, 2008
Project 182, Part III
|Renovation on N9771H is complete! In “Project 182, Part I” [April 2008], we covered the modernization of the aircraft’s avionics panel. We took care of the interior in “Project 182, Part II: Redressing A Skylane” [June 2008], and in this final edition, we address the exterior.|
For our 1982 Skylane project, we contacted Karen Mowrey of Globe Fiberglass in Lakeland, Fla., and asked about the advantages and disadvantages of nonmetal exterior pieces. “Metal may be stronger, but fiberglass offers the obvious benefit of being lighter and more easily shaped into compound curves,” says Mowrey. “Whereas metal has very little flexibility, fiberglass can be more adaptable in areas that need to flex. Metal tends to dent when it suffers an impact, but fiberglass has some give and will bounce back with little or no damage. Wheel fairings, wingtips and horizontal and vertical stabilizer end caps are commonly constructed of some form of composite.”
Mowrey was quick to emphasize the difference between plastic and fiberglass parts. “Plastic is far less forgiving,” Mowrey explains. “It’s much more subject to embrittlement. When it begins to crack, you can try stop-drilling, but it’s like putting a Band-Aid on cancer. The crack will probably still migrate, especially if it’s in a high-vibration area and, eventually, the part is almost bound to split. If an airplane with plastic parts is left outside, especially in a very hot or humid climate, plan on no more than a five-year life for plastic components.
“Properly constructed fiberglass fairings last quite a bit longer, and they’re repairable,” Mowrey comments. “If the airplane is housed inside a hangar, fiberglass components can last for 20 years or more. In the event of hangar rash or other damage, it’s often possible to sand, repair and paint a fiberglass piece, something that may be unlikely with plastic.” All of Globe’s parts are finished in a battleship-gray primer, are easily adaptable to painting and are consistent with many standard aircraft metal primers.
Not surprisingly, any part subject to high heat, such as pieces installed in close proximity to an aircraft engine, must be constructed of flame-retardant materials. Globe uses high-end, eight-ounce fabric that’s designed for strength and durability. In most instances, Globe’s parts will outlast the original manufacturer’s components, and the company builds virtually every external composite part for most of the major manufacturers. That includes the parts listed above, plus tailcones, ventral and dorsal fins, empennage fairings and a variety of other fairings. Globe’s parts are approved for most composite pieces on Pipers, Cessnas, Beeches, Commanders, Aerostars, Bellancas and McDonnell Douglas helicopters.
Finally, of course, once you’ve decided on the colors and the paint design, you have to commit to a shop. In our case, we chose Art-Craft Paint Inc. at Santa Maria Airport on the California coast. Art-Craft has been painting airplanes since 1982, so the company knows a thing or three about the process of applying paint to everything from corporate jets and helicopters to warbirds and homebuilts.
Esmeralda Mendoza, VP and director of operations at Art-Craft, suggests that, by far, the biggest factor in a good paint job is the preparation. “Prep consumes about 80% of our time,” Mendoza explains. “If the surface isn’t properly prepared, it really doesn’t matter if you use a high-quality polyurethane and paint and have a world-class artist do the spraying.
“Total downtime for our paint jobs is 22 days on most aircraft, and we spend 18 days of that in the preparation of the surface,” says Mendoza. “The stripping process is extremely critical in that you have to totally clean all metal surfaces but avoid any contact with fiberglass, Plexiglas or composite parts.
“We can usually strip the old paint in one day; then we begin preparing the airplane for new paint,” Mendoza continues. “The standard contract includes 10 hours of body work to correct minor dings and hangar rash, and that usually covers most aircraft that haven’t suffered any major damage. Our mechanics will survey the airplane and determine if anything is serious enough to demand re-skinning.”