Materials & Hardware

Aircraft fastener holes may require repair after corrosion removal, fastener replacement, or minor damage. This section explains approved hole repair methods, the use of Acres fastener sleeves, and the basic construction and hardware of aircraft control cable and push-pull linkage systems. Many of the blind fasteners are manufactured in oversized diameters to accommodate slightly enlarged … Read more

Aircraft hardware and fasteners are subjected to constant vibration, aerodynamic loads, and operational stresses during flight. To prevent nuts, bolts, screws, turnbuckles, and other components from loosening, various safetying methods are used throughout the aircraft. Proper installation and inspection of safetying devices are essential to maintain structural integrity, system reliability, and flight safety. Safetying Methods … Read more

Many special fasteners produce high strength with lightweight and can be used in place of conventional AN bolts and nuts. When AN bolts are tightened with the nut, the bolt stretches, narrowing the diameter and then the bolt is no longer tight in the hole. Special fasteners eliminate this loose fit, because they are held … Read more

Two classes of mechanically-expanded rivets are discussed here: Self-Plugging Rivets (Friction Lock) The self-plugging (friction lock) blind rivets are manufactured by several companies. The same general basic information about their fabrication, composition, uses, selection, installation, inspection, and removal procedures apply to all of them. Self-plugging (friction lock) rivets are fabricated in two parts: a rivet … Read more

Torque As the speed of an aircraft increases, each structural member becomes more highly stressed. It is therefore extremely important that each member carry no more and no less than the load for which it was designed. To distribute the loads safely throughout a structure, it is necessary that proper torque be applied to all … Read more

Sheets of metal must be fastened together to form the aircraft structure, and this is usually done with solid aluminum-alloy rivets. A rivet is a metal pin with a formed head on one end when the rivet is manufactured. The shank of the rivet is inserted into a drilled hole, and its shank is then … Read more

Installation of Nuts, Washers, & Bolts Bolt & Hole Sizes Slight clearances in bolt holes are permissible wherever bolts are used in tension and are not subject to reversal of load. A few of the applications in which clearance of holes may be permitted are in pulley brackets, conduit boxes, lining trim, and miscellaneous supports … Read more

Aircraft washers used in airframe repair are either plain, lock, or special type washers. Plain Washers Plain washers, both the AN960 and AN970, are used under hex nuts. [Figure 1] They provide a smooth bearing surface and act as a shim in obtaining correct grip length for a bolt and nut assembly. They are used … Read more

Aircraft nuts are made in a variety of shapes and sizes. They are made of cadmium-plated carbon steel, stainless steel, or anodized 2024T aluminum alloy and may be obtained with either right- or left-hand threads. No identifying marking or lettering appears on nuts. Only the characteristic metallic luster or color of the aluminum, brass, or … Read more