What does the MS20426AD-6-5 specification indicate about a rivet?

The specification MS20426AD-6-5 indicates that it is a countersunk rivet with a specific overall length. The 'AD' in the designation is key to understanding that this rivet is a countersunk type, which allows for a flush surface on the assembled structure, reducing aerodynamic drag and providing a smooth finish. Additionally, the '6' in the number indicates the diameter of the rivet in 1/32 inches, which translates to 6/32 or 3/16 inches. The '5' at the end signifies an overall length of 5/16 inches, meaning this rivet is designed to securely fasten components while allowing for a smooth and flush surface finish.

This understanding of the MS20426AD designation is crucial for aircraft assembly and maintenance where precision in fastener selection directly impacts structural integrity and performance.