An aircraft bolt has overall length 1-1/2 inches, shank length 1-3/16 inches, and threaded portion length 5/8 inch. What is the grip length?

• A. 0.875 inch
• B. 0.3125 inch
• C. 0.5625 inch
• D. 0.625 inch

Answer: (C)

Grip length is the portion of the bolt’s shank that actually participates in clamping the parts, i.e., the unthreaded part of the bolt that lies within the joint. To find it here, subtract the threaded portion length from the shank length: 1-3/16 inches minus 5/8 inch equals 9/16 inch, which is 0.5625 inch. So the grip length is 9/16 inch.