AMS 274 Turbines Unit 3 Exam Review (Hancock) Questions and Answers
State three functions of the oil tanks overboard relief 1. Maintains positive pressure
valve: 2. Vents to prevent tank failure
3. Allows depressurization of tank at shutdown
What is the function of the oil tanks dwell chamber? Separates air from the oil (bleeds it out from the scavenge system)
What is the position of the internal valves of the Aneroid valve is open
pressurizing and vent valves when the aircraft is on the
ground?
What is the position of the internal valves of the Aneroid begins to open at around 8000-10000 ft, and will be completely closed at
pressurizing and vent valves when the aircraft is at 20k 20000 ft
ft?
What is a "hot tank"? The cooler is located in the pressure subsystem
What is a "cold tank"? The cooler is located in the scavenge system
Explain trimming: Also known as tuning, is when you make adjustments to the fuel control system
for idle and max power (there are 2 adjustments)
Explain the thermostatic valve position and flow of fuel The thermostatic valve is open and ONLY fuel is flowing
and oil when the oil is cold in a fuel/oil cooler:
Explain the thermostatic valve position and flow of fuel The thermostatic valve is closed and forces oil through the cooler with the fuel
and oil when the oil is hot in a fuel/oil cooler: (the two mix and oil heats the fuel)
Oil jets: Fixed nozzles that apply constant flow to all the bearings (fixed nozzles used for
this reason)
Chip detector: Checks for the presence of ferrous material due to internal breakdown
What happens when ferrous pieces get into a chip When chips get in they attach to the magnet and complete the circuit to the
detector? electrode and cause a chip light to illuminate in the cockpit
Gas turbine engines require what kind of oil? Synthetic oil (cannot be interchanged with reciprocating engine oil)
When should the oil in turbines be serviced and why? Just after shutdown when the oil is still warm so you don't over-service the
system
What else can you use to cool oil aside from fuel? RAM air
Delta P does what? Has a light that denotes an impending filter bypass. This allows oil to bypass the
filter in case of a clogging/oil is too cold
State three functions of the oil tanks overboard relief 1. Maintains positive pressure
valve: 2. Vents to prevent tank failure
3. Allows depressurization of tank at shutdown
What is the function of the oil tanks dwell chamber? Separates air from the oil (bleeds it out from the scavenge system)
What is the position of the internal valves of the Aneroid valve is open
pressurizing and vent valves when the aircraft is on the
ground?
What is the position of the internal valves of the Aneroid begins to open at around 8000-10000 ft, and will be completely closed at
pressurizing and vent valves when the aircraft is at 20k 20000 ft
ft?
What is a "hot tank"? The cooler is located in the pressure subsystem
What is a "cold tank"? The cooler is located in the scavenge system
Explain trimming: Also known as tuning, is when you make adjustments to the fuel control system
for idle and max power (there are 2 adjustments)
Explain the thermostatic valve position and flow of fuel The thermostatic valve is open and ONLY fuel is flowing
and oil when the oil is cold in a fuel/oil cooler:
Explain the thermostatic valve position and flow of fuel The thermostatic valve is closed and forces oil through the cooler with the fuel
and oil when the oil is hot in a fuel/oil cooler: (the two mix and oil heats the fuel)
Oil jets: Fixed nozzles that apply constant flow to all the bearings (fixed nozzles used for
this reason)
Chip detector: Checks for the presence of ferrous material due to internal breakdown
What happens when ferrous pieces get into a chip When chips get in they attach to the magnet and complete the circuit to the
detector? electrode and cause a chip light to illuminate in the cockpit
Gas turbine engines require what kind of oil? Synthetic oil (cannot be interchanged with reciprocating engine oil)
When should the oil in turbines be serviced and why? Just after shutdown when the oil is still warm so you don't over-service the
system
What else can you use to cool oil aside from fuel? RAM air
Delta P does what? Has a light that denotes an impending filter bypass. This allows oil to bypass the
filter in case of a clogging/oil is too cold
