Don't Wing It

Dec. 9, 2009
Fall protection tips for aircraft maintenance

No matter what type of aircraft a mechanic is working on — prop or jet, private or commercial, narrow- or wide-bodied plane — work surfaces are sloped and slippery, intensifying fall hazards. Even if this is the hundredth time a worker has performed the same job, the worker must be aware of the surroundings. It only takes one slip or misstep for a fall to occur.

Whether conducting a routine maintenance check or carrying out a repair job, a fall protection system must be in place anytime you are working on an aircraft surface more than a few feet off the ground. Even if it’s a routine repair that will only take a few minutes to complete, and the risk of falling seems improbable — think again. It only takes a second for a fall to occur.

Depending upon the application, OSHA mandates fall protection when working on surfaces elevated by more than 4 or 6 feet. There are multiple fall protection solutions for the aviation industry to ensure maintenance and repair tasks are completed efficiently and most importantly, safely. Below are tips to help select the best-suited fall protection solutions for applications in the aviation industry.

Choose the right equipment
Workers should always use fall protection equipment that is lightweight, comfortable, compact, and mobile.

There are three parts to a personal fall protection system: anchorage, body support, and connector. The anchorage is a vital part of any fall protection system and many options are available to suit the location of the aircraft, whether parked on the tarmac or in a hangar.

A full-body harness distributes fall arrest forces to the upper thighs, pelvis, chest, and shoulders. When selecting a harness, consider the worker’s comfort and time spent wearing the harness, as well as the application and environment. A comfortable harness has padding and lining, as well as adjustment points on the legs, waist, chest, and shoulders. Breathable lining that wicks moisture away from the body helps workers stay dry and comfortable in hot or cold weather.

There are two main connector options to connect the anchorage to the harness: lanyards and self-retracting lifelines (SRLs). If a task requires more mobility, the worker should use an SRL. A shock-absorbing lanyard can be used when less mobility is required. A shock-absorbing lanyard limits the fall arrest forces exerted on the body in the event of a fall. In order to prevent scratching the plane’s surface, workers should use harnesses and connectors with covered hardware elements and a web loop in place of the back D-ring.

Permanent overhead systems
The best solution for almost all types of aircraft maintenance work is tying off to a permanent overhead engineered system. There are two basic types of permanent overhead systems: a cable system and a horizontal rail system. A cable system is strung horizontally across hangar roof beams and supported by intermediate brackets spaced evenly to help distribute the forces of a fall. The shuttle, the element that moves along the line, can navigate intermediate brackets, allowing the system to be engineered in a virtually unlimited array of configurations.

Cable systems are usually limited to large aircraft with increased fall clearance because in the event of a fall, the cable will dip slightly where the weight of the worker is deflected on the line.

Unlike cable systems, horizontal rail systems are desirable for both large and small aircraft. These rigid systems are also fixed to overhead support structures, but a partially sealed aluminum rail with a trolley that moves within it serves as the anchor, rather than a flexible cable. The rigid overhead anchorage point allows horizontal rail systems to be used for small aircraft with less fall clearance. Both systems can be engineered to span the needed length.

Permanent overhead engineered systems are convenient for both stationary and mobile work such as damage repair, inspections, and routine maintenance along the fuselage. Most systems allow the worker to bypass the brackets hands-free, so the user never has to disconnect from the lifeline, increasing safety and productivity. Depending on the system, one to five workers can be connected to it simultaneously. The disadvantage to these systems is that they cannot be moved.

A mobile system is necessary
Location of the airplane is a primary consideration when selecting a fall protection system. With most aircraft schedules, it is difficult to know the exact tarmac location or hangar an aircraft will be in when maintenance is needed. If the aircraft cannot be parked directly under a permanent system in a hangar, or work needs to be completed on the tarmac, a portable system is required. Leased facilities may lack a permanent overhead system, or the system may be in use. If the task can’t wait, a mobile fall protection system is needed.

There are three main types of mobile fall protection systems: free-standing, aerial lifts, and vacuum anchors. Free-standing systems provide an overhead anchorage point that limits the free-fall distance. Most systems can be maneuvered into place by hand, forklift, or maintenance vehicle. Additional advantages include allowing multiple workers to be tied off to the system and most systems are height-adjustable to work on small or large aircraft. The disadvantage of a free-standing system is that mobility is limited to a safe working range, which varies based on the system.

There are two types of free-standing systems commonly used in the aviation industry: ladder access systems and horizontal rail systems. A ladder access system provides easy access to an elevated work area with fall protection from the ground up, so at no point would a worker be unprotected from a fall. A semi-enclosed platform at the top of the ladder allows a worker to access the wing or fuselage, or perform a quick task on the edge or side of the aircraft. Fall arrest anchorages are located at the top of the platform for attachment of a personal fall arrest system. These systems are ideal for reaching extreme heights such as the tail of a large commercial jet.

Free-standing horizontal rail systems are essentially the same as horizontal rail systems used in overhead permanent engineered systems, except they are mobile and height adjustable. Workers can connect to anchors located on the same or separate rails. A rail system avoids direct contact with the aircraft, but there are height limitations compared to the ladder access system.

Aerial lifts are a good choice for gaining access to an overhead fall protection system or for stationary work. Cherry pickers and scissor lifts are the most commonly used aerial lifts. They provide quick accessibility to the side or edge of the aircraft. A disadvantage of lifts is that they can damage the aircraft if they come into contact with the fuselage or wing. Another disadvantage is the limited positioning in the bucket or cage of a lift device that can quickly cause workers to become uncomfortable and restrict work angles.

Vacuum anchors are the newest fall protection system available for the aviation industry. These systems attach directly to the wing or crown of an aircraft without penetrating or damaging the surface. When vacuum anchors were introduced they were quite heavy and a large air pump was needed to attach the anchor to the aircraft. Today vacuum anchors are lightweight, making them extremely portable, and they offer the option of using an onboard compressed air bottle or connection to an independent air supply to seal the anchor to the surface.

A fall arrest or restraint lanyard, depending on what the anchor is rated for, can be attached to the vacuum anchor and connected to the worker’s full-body harness. For increased mobility, two anchors can be set up with a horizontal lifeline running between them. This configuration allows one or two workers to tie off to the system. The major advantages of the vacuum anchor are its portability and quick setup time. With some systems weighing in at less than 20 pounds, it is extremely easy to transport and set up. The disadvantage is that the system should only be used on larger aircraft due to the fall clearance required when workers are tying off at foot level.

Time is of the essence in the aviation industry; quick, unscheduled repairs are common. A highly portable vacuum anchor system that a mechanic can easily carry to the airplane’s site can increase productivity and efficiency. A portable system as a backup is a necessity, as it’s often impractical to wait for an overhead fall protection system to become available.

Conclusion
When climbing atop an aircraft, large or small, consider which type of fall protection system best fits the application and use it. Whether a five-minute job or a five-hour job, a fall protection system must be utilized when working on an airplane’s surface, as it only takes a second for a fall to occur. Don’t wing it!

Tim Maroushek is product manager for systems and anchors with Capital Safety, a designer and manufacturer of height safety and fall protection equipment under the DBI-SALA and PROTECTA brands. Capital Safety offers a line of fall protection and rescue systems, as well as training courses. For more information, contact Capital Safety at (800) 328-6146 or visit www.capitalsafety.com.