What size AN bolts would be required for a bolt pattern drilled with holes that are .3125 inch in diameter?

When determining the appropriate size of AN bolts for drilled holes, the bolt size must correspond to the size of the drilled holes to ensure a proper fit. The hole diameter here is .3125 inches, which correlates to the correct AN bolt size.

AN bolts are categorized by their nominal diameter in sixteenths of an inch. For example, an AN3 bolt has a diameter of 3/16 inch, or approximately .1875 inches; an AN4 bolt measures 1/4 inch, or .250 inches; an AN5 bolt measures 5/16 inches, equating to .3125 inches; and an AN6 bolt is 3/8 inch in diameter, which is .375 inches.

Based on this, AN5 bolts are precisely the correct choice for holes that are .3125 inches in diameter, providing a proper and secure connection without compromising integrity or safety.

This understanding underscores the importance of correctly matching bolt sizes to corresponding hole diameters in structural applications and aircraft maintenance to maintain airworthiness and safety.