Like any other key piece of equipment, aircraft towbars must be maintained regularly to preserve their useful life as well as perform their job safely and efficiently. Aircraft towbar preventative maintenance is vital to their continued operation and safety. Our approach to preventative maintenance on towbars is to follow maintenance procedures for each component of the towbar, including the towbar body, head mechanism, shear pins, tow rings, lift mechanism, and carriage, wheels, and hubs.
Although many planes can use reverse thrust to move backwards, this movement can damage the jet engines of the aircraft and poses a danger to nearby buildings and equipment. Machines such as tractors and tugs can be used to safely move aircraft backward in a process known as “pushback.” Towbars are attached to these tractors and tugs as well as to the nose of the plane being moved. Towbars are an indispensable part of the pushback and towing processes and are used with everything from small, light aircraft to massive commercial aircraft.
Towbar Body Maintenance
One of the key maintenance areas is the body (or tube) of the towbar. We carefully check the body for straightness, and if it is bowed then it is taken out of service immediately and repaired or replaced. The towbar body must also be inspected for signs of cracks. If cracks are present, the towbar body is repaired by one of our certified welders.
Head Mechanism Maintenance
There are many moving parts that need inspection in the towbar head mechanism, and this is true whether it uses a pin capture or clamp style. First, all moving parts (including linkages) are lubricated and checked for wear. For pivot-designed heads, the pivot bolt is removed to check its condition and replaced it if it seems suspect. We also verify that the actuator handle correctly locks into position.
Preventative Maintenance for Shear Pins
The shear pins carry most of the load during an aircraft transfer. They are designed to shear at a predetermined stress (psi) to prevent damage to the aircraft. As part of their regular maintenance, shear pins are inspected for the following: cracks, indentations, straightness, and overall condition. If shear pins show any signs of damage, they are replaced immediately. Inspecting the shear pins is an important step in any aircraft towbar preventative maintenance program.