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The installation of common threaded aerospace fasteners by the application of a torque to a nut or collar is made possible by an internal wrenching element or recess feature adapted to the threaded end of a pin, which accepts a mating anti-rotation key designed to partially balance the applied torque. In applications such as the mechanical joining of composite structures accomplished by wet clearance fit installations of permanent fasteners, high nut or collar seating torques not adequately opposed by frictional resistance at the contact surfaces of the fastener and joint members effectively shift a greater proportion of the torque reaction requirement onto the recess and mating anti-rotation key which in turn can experience high torsional stresses exceeding their design capability and result in frequent service failures.

Structural panel fasteners have been used in the aerospace industry for longer than the previous half century. This paper presents the new FC43® Panel Fastener with a novel retaining feature which enables the use of a full shank stud. The retaining feature can be used with a variety of thread configurations and is independent of nut style or head configuration, providing an unprecedented modularity for this type of fastening system. With a stud design that is free of slots or axial recesses, the FC43® provides higher mechanical performance than existing equivalent panel fasteners. Mechanical characteristics and performance comparisons with the most commonly used panel fasteners in the aerospace industry are also presented.

Following the trend in automotive manufacturing, electric cordless tooling platforms are gradually being adopted for aerospace assembly tool systems. This paper introduces a new portable aerospace fastener assembly tool system based on the cordless electric technology platform. These systems are significantly more accurate than traditional pneumatic–based assembly tool systems and offer a range of process monitoring options. Cordless assembly tool systems make the assembly process easier, faster, safer and more accurate. These systems have the ability to provide traceability with time & date stamp for each installed fastener and provide wireless communication to enable process monitoring in real time. A comparison with traditional aerospace tool systems is made, in terms of historical evolution and working performance. Lessons learned from automotive applications are brought to aerospace industry. Key benefits include better ergonomics, improved accessibility, productivity and cost.

The installation of aerospace fasteners with pneumatic or cordless tools generally requires specialized systems which are dedicated to the fastener hex size and torque, often requiring laborious disassembly for a configuration change. This paper presents a quick change system that can be used together with a large variety of tooling configurations and provides instant socket exchange without requiring wrenching or disassembly. A comparison with traditional socket system is made, highlighting the characteristics and benefits of this new technology in terms of ergonomics, productivity and cost.

Light weight aerospace fastening collars were manufactured from 2099 alloy which is a new generation Al-Li alloy developed by Alcoa. The collars studied in this work are threaded self-locking collars with controlled torque-off feature and are to be used in a fastener assembly with a treated pin. The mechanical properties of 2099 collars were measured and compared to the ones made of incumbent alloys such as 7075 and 2024. It was found that the 2099 collars were 16% lighter but provided the equivalent mechanical properties. In addition, the corrosion characteristics of the 2099 collars were studied using the salt spray and alternate immersion test methods. It was observed that 2099 collars exhibited an improved corrosion performance as compared to the base line 7075 collars. This paper presents the results obtained from the mechanical and corrosion testing of the Al-Li collars along with the weight saving potentials of the new product.