The Navy Enlisted Classification (NEC) system supplements the enlisted rating structure in identifying personnel on active or inactive duty and billets in manpower authorizations. NEC codes identify a non-rating wide skill, knowledge, aptitude, or qualification that must be documented to identify both people and billets for management purposes.
For example, if a Navy police officer ( MA -- Master at Arms ) receives specialized training as a K-9 Dog Handler, he/she would be awarded NEC MA-2005. From that point on, the sailor could be assigned to Navy law enforcement duties involving military working dogs.
Below are the NECs for the AVIATION SUPPORT TECHNICIANS (AS) community area:
AS-7601 Support Equipment Cryogenic Mechanic (APPLIES TO: AS)
AS-7603 Support Equipment Air Conditioning and Mobile Maintenance Facility (MMF) Technician (APPLIES TO: AS)
AS-7606 Support Equipment Gas Turbine Mechanic (APPLIES TO: AS)
AS-7607 Support Equipment Tow Tractor Technician (APPLIES TO: AS)
AS-7609 Support Equipment Maintenance Manager (APPLIES TO: AS)
AS-7612 SE Hydraulic Intermediate Maintenance Technician (APPLIES TO: AS)
AS-7616 Maintenance Crane Intermediate Maintenance Technician (APPLIES TO: AS)
AS-7617 Crash Equipment Technician (SEA) (APPLIES TO: AS)
AS-7618 Afloat Support Equipment Technician (APPLIES TO: AS)

