The GSE/GSM Ratings
The Navy Gas Turbine Systems Technician rating was established in 1978.
The Navy's computerized personnel system associates the rating name with an alphanumeric Navy Occupational Specialty (NOS) code. For GS, the NOS is B120; for GSE, B121; and for GSM, B122.
Gas Turbine Systems Technicians are broken down into two separate ratings with one whose core is electrical (GSE) and the other mechanical (GSM). GSs operate, repair, and perform organizational and intermediate maintenance on gas turbine engines, main propulsion machinery (including gears, shafting, and controllable pitch propellers), assigned auxiliary equipment, propulsion control systems, assigned electrical and electronic circuitry up to the printed circuit, and alarm and warning circuitry.
The active duty GSE rating requires a 60 month (5 year) minimum enlistment contract. The GSM rating requires a 60 month (5 year) service obligation (effective FY-13).
Gas Turbine Systems Technician - Electrical (NOS B121)
Gas Turbine Systems Technicians (Electrical) operate, repair and perform organizational and intermediate maintenance on electrical components of gas turbine engines, main propulsion machinery, auxiliary equipment, propulsion control systems, and assigned electrical and electronic circuitry up to the printed circuit and alarm warning circuitry. They operate electric plant main and propulsion control equipment, and they locate circuit failures and replace parts.
GSEs measure current, voltage and resistance, and test for shorts, grounds and continuity. They test protective circuitry, and test, service and replace batteries. GSEs perform preventive maintenance on digital data equipment and control and monitor circuits, measure insulation resistance, and repair electrical/electronic cables, wiring, and connectors. They maintain alarm, indicating and warning systems, and maintain and repair gas turbine engines and auxiliary equipment. GSEs work with blueprints, schematics, and charts, and perform administrative procedures related to gas turbine propulsion system operation and maintenance.
Gas Turbine Systems Technician (Electrical) class "A" school is approximately 22 weeks long, and is located in Great Lakes, Illinois.
Gas Turbine Systems Technician - Mechanical (NOS B122)
Gas Turbine Systems Technicians (Mechanical) operate, repair and perform organizational and intermediate maintenance on mechanical components of gas turbine engines, main propulsion machinery (including main reduction gears, shafts and controllable pitch propellers), assigned auxiliary equipment, and propulsion control systems. They also maintain and operate ship's service gas turbine generators and support systems, maintain the controllable pitch propeller system, control ship's service steam water chemistry.
GSMs operate electric plant control and main propulsion equipment, pumps, turning gears, air compressors, oil purification systems, low pressure air dehydrators, and engineering control systems. They work with blueprints, schematics and charts to maintain and repair gas turbine engines and auxiliary equipment. They perform preventive maintenance on ship's fuel system and air system, sea water service system, waste drain system, oil purification system, and manually operated valves. They also perform work area inspections, operate standard test equipment, and test lubricating oil and distillate fuels for contamination, neutralization, and precipitation.
Gas Turbine Systems Technician (Mechanical) class "A" school is approximately 15 weeks in duration, and is located in Great Lakes, Illinois.
Career Sea - Shore Rotation Chart
Sea tours and shore tours for Sailors that have completed four sea tours will be 36 months at sea followed by 36 ashore until retirement.
Sailors in the Gas Turbine Systems Technician rating can expect to spend more than half their career on sea duty assignment. Sea tour lengths for the GSE/GSM ratings will not involuntarily exceed 60 months for Sailors with less than 20 years of service (YOS) and 48 months for Sailors with more than 20 YOS. Shore tour lengths between sea tours will be set to 36 months long. Manning conditions at sea may require the need to request sea tour extension or shore tour curtailments to ensure all sea duty billets are filled.
Qualifications, Interests, and Working Environment
Personnel in this rating must have mechanical ability, manual dexterity and normal color perception. They should also have experience working with machines, in electronics/electrical fields and have had some courses in physics.
Normal color perception is required. Members of these rates are not required to be citizens of the United States.
Gas Turbine Systems Technicians usually work in engine rooms or shops that may be hot and noisy aboard many types of modern ships. At shore they may work at major repair or training facilities. Work is physical and analytical (trouble-shooting) for electronic and mechanical components. GS ASVAB Test score requirements.
The American Council on Education recommends that semester hour credits be awarded in the vocational certificate and lower-division bachelor's/associates degree categories for courses taken in this rating on technical mathematics, applied physics, gas turbines and blueprint reading.
Date Page Modified: December 21, 2016.