NASA-STD-5020A: Requirements for Threaded Fastening Systems

TL;DR — NASA’s standard for bolts — preload, locking, analysis and verification, at spaceflight tolerances.

⬇ Download the archived copy — kept here so the document survives its source going dark. US federal government work (17 USC §105).

NASA-STD-5020A with Change 1 (2019-02-11).

The complete engineering standard for threaded fasteners in spaceflight hardware: preload uncertainty, locking features, separation analysis, fatigue, and how each must be verified.

As a document it is a good answer to the question of what ‘rigorous’ actually costs — 114 pages to specify a bolt, because the failure mode is unrecoverable.

Where this came from

• Will Manidis’s “most underrated PDF” thread

114 pages. A copy is archived locally against link rot; the header links the original source.