Aircraft Parts and Auxiliary Equipment, Not Elsewhere Classified - Introduction

Introduction
This category includes establishments primarily engaged in manufacturing aircraft parts and auxiliary equipment, not elsewhere classified. This industry also includes establishments owned by manufacturers of aircraft parts and auxiliary equipment and primarily engaged in research and development on aircraft parts, whether from enterprise funds or on a contract or fee basis. Establishments primarily engaged in manufacturing or assembling complete aircraft are classified in SIC 3721: Aircraft; those manufacturing aircraft engines and parts are classified in SIC 3724: Aircraft Engines and Engine Parts; those manufacturing aeronautical instruments are classified in SIC 3812: Search, Detection, Navigation, Guidance, Aeronautical, and Nautical Systems and Instruments; those manufacturing aircraft engine electrical equipment are classified in SIC 3694: Electrical Equipment for Internal Combustion Engines; and those manufacturing guided missile and space vehicle parts and auxiliary equipment are classified in SIC 3769: Guided Missile and Space Vehicle Parts and Auxiliary Equipment, Not Elsewhere Classified. Establishments not owned by manufacturers of aircraft parts but primarily engaged in research and development on aircraft parts on a contract or fee basis are classified in SIC 8731: Commercial and Biological Research.