NAVY AVIATION MACHINIST MAIN EXAMINATION
PAPER 2026/2027 QUESTIONS AND SOLUTIONS RATED
A+
✔✔Boost Pump - ✔✔Fuel flow to the engine-driven fuel pump. Submerged unit
containing a centrifugal pump and an electric motor (USED WITH FEED CELL)
✔✔Strainers - ✔✔Prevent large foreign particles from entering the fuel system
✔✔Manually Operated Shut-Off Valves - ✔✔Installed where it is desirable to shut off the
fuel while it is being removed or replaced
Closed to stop fuel flow in case of fire
✔✔Electrically Operated Shut-Off Valves - ✔✔Referred to at gate valves
Control fuel flow during refueling and fuel transfer
✔✔Fuel Level Control Valves - ✔✔Used to control the level of fuel in the fuel cell/tanks
✔✔Check Valves - ✔✔Allows fuel to flow in one direction only
✔✔Selector Valve - ✔✔Allows the pilot to control the flow for selected purposes
✔✔Fuel Probes - ✔✔Used to transmit an electrical signal to the cockpit / flight station
fuel quantity indicator to register the amount of fuel in the cells/tanks.
✔✔Aircraft Fuel Subsystems - ✔✔Pressurization System, Vent System, Dump System,
and Pressure Fueling System / Defueling System
✔✔Pressurization System - ✔✔Pressurize the aircraft fuel system for fuel transfer
✔✔Vent System - ✔✔Vent fuel cells/tanks to prevent pressure build up
✔✔Dump System - ✔✔Dump excess fuel overboard
✔✔Pressure Fueling / Defueling System - ✔✔Provides a means of pressure fueling /
defueling on the ground
✔✔Auxiliary Fuel System's Purpose - ✔✔Provide a means of increasing the aircrafts
fuel capacity. This is done through the use of external tanks
✔✔External Tanks - ✔✔Store additional fuel
, Varies in size but holds 150, 300, 400
Mounted on pylons on the underside of wings and centerline of the fuselage
Are streamlined and may be jettisoned
✔✔In-Flight Refueling System - ✔✔Allow an aircraft to receive fuel during flight
Connected directly into the Pressure Fueling System of the receiving aircraft and
permits the fuselage cells, wing tanks, and external tanks to be filled to capacity
Accomplished by transferring fuel from a tanker aircraft, or a ship, through a refueling
nozzle connected to the in flight refueling probe or servicing manifold of the receiving
aircraft
✔✔Aircraft Fuel System Maintenance Support Equipment - ✔✔Multi-RAE 50,
Multimeter, Explosive-proof lighting/flashlight, Portable purging equipment, and
Breathing Air System
✔✔Multi-RAE 50 - ✔✔Used to detect fuel vapor levels
✔✔Multimeter - ✔✔A measuring instrument for current, voltage, and resistance
✔✔Explosive-Proof Lighting / Flashlight - ✔✔Spark resistant lighting used to aid visibility
✔✔Portable Purging Equipment - ✔✔Air blower used to evacuate the vapors from the
fuel cell
✔✔Breathing Air System - ✔✔Air-supplied respirator used to supple clean, compressed
air
✔✔Fuel Cell Entry Process (Before Maintenance) - ✔✔(1) Ground the aircraft to prevent
static electricity from causing fuel vapors to ignite
(2) Defuel the aircraft
(3) Rope off the aircraft maintenance area
(4) Disconnect the battery
(5) Pull the appropriate circuit breakers
(6) Post tag-out signs
(7) Pencil drain the fuel cell
✔✔Fuel Drain - ✔✔Used to drain condensation from the fuel system
Drain excess fuel from the cells'tanks
Drain samples for contamination checks
PAPER 2026/2027 QUESTIONS AND SOLUTIONS RATED
A+
✔✔Boost Pump - ✔✔Fuel flow to the engine-driven fuel pump. Submerged unit
containing a centrifugal pump and an electric motor (USED WITH FEED CELL)
✔✔Strainers - ✔✔Prevent large foreign particles from entering the fuel system
✔✔Manually Operated Shut-Off Valves - ✔✔Installed where it is desirable to shut off the
fuel while it is being removed or replaced
Closed to stop fuel flow in case of fire
✔✔Electrically Operated Shut-Off Valves - ✔✔Referred to at gate valves
Control fuel flow during refueling and fuel transfer
✔✔Fuel Level Control Valves - ✔✔Used to control the level of fuel in the fuel cell/tanks
✔✔Check Valves - ✔✔Allows fuel to flow in one direction only
✔✔Selector Valve - ✔✔Allows the pilot to control the flow for selected purposes
✔✔Fuel Probes - ✔✔Used to transmit an electrical signal to the cockpit / flight station
fuel quantity indicator to register the amount of fuel in the cells/tanks.
✔✔Aircraft Fuel Subsystems - ✔✔Pressurization System, Vent System, Dump System,
and Pressure Fueling System / Defueling System
✔✔Pressurization System - ✔✔Pressurize the aircraft fuel system for fuel transfer
✔✔Vent System - ✔✔Vent fuel cells/tanks to prevent pressure build up
✔✔Dump System - ✔✔Dump excess fuel overboard
✔✔Pressure Fueling / Defueling System - ✔✔Provides a means of pressure fueling /
defueling on the ground
✔✔Auxiliary Fuel System's Purpose - ✔✔Provide a means of increasing the aircrafts
fuel capacity. This is done through the use of external tanks
✔✔External Tanks - ✔✔Store additional fuel
, Varies in size but holds 150, 300, 400
Mounted on pylons on the underside of wings and centerline of the fuselage
Are streamlined and may be jettisoned
✔✔In-Flight Refueling System - ✔✔Allow an aircraft to receive fuel during flight
Connected directly into the Pressure Fueling System of the receiving aircraft and
permits the fuselage cells, wing tanks, and external tanks to be filled to capacity
Accomplished by transferring fuel from a tanker aircraft, or a ship, through a refueling
nozzle connected to the in flight refueling probe or servicing manifold of the receiving
aircraft
✔✔Aircraft Fuel System Maintenance Support Equipment - ✔✔Multi-RAE 50,
Multimeter, Explosive-proof lighting/flashlight, Portable purging equipment, and
Breathing Air System
✔✔Multi-RAE 50 - ✔✔Used to detect fuel vapor levels
✔✔Multimeter - ✔✔A measuring instrument for current, voltage, and resistance
✔✔Explosive-Proof Lighting / Flashlight - ✔✔Spark resistant lighting used to aid visibility
✔✔Portable Purging Equipment - ✔✔Air blower used to evacuate the vapors from the
fuel cell
✔✔Breathing Air System - ✔✔Air-supplied respirator used to supple clean, compressed
air
✔✔Fuel Cell Entry Process (Before Maintenance) - ✔✔(1) Ground the aircraft to prevent
static electricity from causing fuel vapors to ignite
(2) Defuel the aircraft
(3) Rope off the aircraft maintenance area
(4) Disconnect the battery
(5) Pull the appropriate circuit breakers
(6) Post tag-out signs
(7) Pencil drain the fuel cell
✔✔Fuel Drain - ✔✔Used to drain condensation from the fuel system
Drain excess fuel from the cells'tanks
Drain samples for contamination checks
