With the wide diversity of aircraft in use today, many Fixed Base Operators are changing from model special aircraft hangars to general use hangars and are increasingly moving their inspection and some maintenance out-of-doors. As the work environment changes, so do the ways maintenance workers access aircraft when they're working above ground level.
Common sense regarding the need to protect workers along with OSHA regulations and insurance requirements has necessitated changes in the way workers are protected from falling. OSHA regulations require that workers be protected from falls when they are working at heights greater than six feet. Fall protection can be provided by guardrails, safety nets, and/or a personal fall protection system.
The use of aerial work platforms in aircraft maintenance is limited by the difficulty in providing worker access to all parts of a plane's exterior while being protected from falls. In the past, sections of the wings, stabilizers, and fuselage crown were impossible to reach from the basket of an aerial work platform. Jet Blast ratings are also sometimes required when aerial work platforms are working around terminals.
This access challenge has been answered by JLG Industries, Inc. with the introduction of their new Fall Arrest Platform designed especially for aircraft inspection and maintenance. The JLG® Fall Arrest Platform allows workers to move outside the basket to access the plane's exterior while still having fall protection in compliance with OSHA requirements. The new Fall Arrest Platform system provides a way to tether workers to the boom's basket without restricting their movement within a radius of six feet.
When aircraft structured hangars were used, cables could be hung from the ceiling above certain areas of the plane, and workers could use them to attach a lanyard for those occasions when they had to leave the basket. It was and is a reasonably satisfactory solution when working inside the hangars, but not feasible when maintenance is required outside. As a substitute, a rolling gantry with cables attached to it has been used. It's bulky and time consuming since the gantry must be moved from plane to plane for it to be in position.
Another attempt at meeting fall protection requirements used a customized platform, dubbed the "playpen", on a standard aerial work platform. It had expandable railings that extended outward to create a large area around a conventionally sized boom and really didn't provide a total system of fall protection. When the guardrails extend over a convex area, there could be a gap between the bottom rail and the aircraft's surface that a worker could slide through since there wasn't a floor under the expanding railings.
A newer concept for providing lanyard anchorage is suction cups. The cups are designed to be attached to a flat, smooth surface, and then have the lanyard attached. The difficulty with the concept is that aircraft have very few smooth surfaces where work is being done, and what surfaces there are, have rivets in them that can prevent a vacuum from being created and holding the cup. There is also no way of determining if the suction cup is holding with sufficient adhesion to provide proper fall protection.
Scissor lifts offer the advantage of a large surface area for workers to move around and have platform capacities up to 1,000 pounds in electric drive models and up to 2,500 pounds in heavy duty, rough terrain models. But, other than a slide-out platform extension, scissor lifts are limited to vertical reach. They're fine for working on wing mounted engines or landing gear but aren't satisfactory for the tops of wings and other areas requiring extended reach.
Telescoping and articulated boom lifts do have an extended, all-around reach capability and can be maneuvered to most areas of an aircraft's exterior. Industry and regulatory standards require workers to stay within the platform, which makes it difficult to reach areas around the platform when it is extended over a wing.
The Closest Thing to Wings Guidelines for establishing a fall protection program By Keith Jackson September 2001 Although the issue has received little attention in the aerospace...