Purpose This SAE Aerospace Standard (AS) establishes the requirements for 37 degree flared tube fittings or machined internal cone fluid connection fittings for use with 37 degree external cone@ spherical nose and seal ring fittings in all types of aerospace fluid systems. Classification Tube fittings shall be furnished in types@ styles and sizes designated by the applicable AS@ AN@ and MS standards. This specification is a similar and an improvement to MIL-F-5509 for 37 degree flared tube fittings. It is intended to serve as the procurement specification for the fittings described herein.