SAE AS8879A

This SAE Aerospace Standard (AS) specifies the characteristics of the UNJ profile inch series of screw threads, to include a mandatory controlled radius of 0.18142P to 0.15011P at the root of the external thread and with a minor diameter of both external and internal threads increased to provide a basic thread height of 0.5625H in order to accommodate the external thread maximum root radius. The following detailed requirements are included:aUNJ basic profile and design profiles.bStandard series of diameter-pitch combinations for nominal thread diameters from .060 to 6.000 inches.cStandard thread classes and form tolerances.dFormulae for thread dimensions and tolerances.eMethod of designating UNJ threads.fAcceptance and verification requirements.gTables for selected diameter-pitch combinations for aerospace screws, bolts, nuts, shaft and bearing retaining screw threads, fluid fittings, and other component thread sizes.hTables for UNJ screw threads limiting dimensions and tolerances.iSymbols for UNJ thread dimensions and tolerances.