AMS 274 Unit 4 Exam Questions with Answers
A typical Gear ratio for an air turbine starter is 25:1. If the turbine is rotating @ 80,000
RPM's, what would the input RPM be to the gear box? - -3,200 RPM
-With a variable vane system when will the vanes be most closed? - -at Low RPM
-What happens if the vanes are stuck in the open position? - -Engine will stall in low
power
-A clicking noise heard from an air turbine starter on engine coast down is a result of
what? - -Pawls re-engaging and riding the ratchet in case we need a re-start
-Which igniter plug requires special handling due to semi-conductor material? - -Low
voltage shunted surface gap (Self Ionizing)
-What does the semi conductor material do when its HOT and COLD? - -Cold- Conducts
Hot- Isolates
-What is autoignition and what does it sense? - -Ensures instantaneous igniton if an engine
loses power. Senses Torque, Oil Pressure, and loss of Compressure dischatge pressure
-What positions are fail type anti-ice valves in? - -Powered closed and spring loaded open
-What instrument indication would you most likely see when engine anti-ice is turned on?
- -Slight Rise in EGT (10 Degrees)
-Starting sequence - -Starter, Ignition, Fuel
-When do you disengage the starter? - -When it reaches self accelerating speed
-Where is the Pressure Regulating and Shutoff valve located? - -Pneumatic starter Unit
-What does the PRSV do? (Pressure Regulating, and Shutoff valve) - -controls airflow to
the pneumatic starter
-What parameter is the most critical to observe? - -TIT
-What indicates a successful start on a turbine engine? - -Rise in EGT
-At what RPM is a stall most likely to occur? - -Low-Medium
-When are the bleeds open? - -at Low power
-What if the bleeds are open @ High power? - -High EGT is expected
A typical Gear ratio for an air turbine starter is 25:1. If the turbine is rotating @ 80,000
RPM's, what would the input RPM be to the gear box? - -3,200 RPM
-With a variable vane system when will the vanes be most closed? - -at Low RPM
-What happens if the vanes are stuck in the open position? - -Engine will stall in low
power
-A clicking noise heard from an air turbine starter on engine coast down is a result of
what? - -Pawls re-engaging and riding the ratchet in case we need a re-start
-Which igniter plug requires special handling due to semi-conductor material? - -Low
voltage shunted surface gap (Self Ionizing)
-What does the semi conductor material do when its HOT and COLD? - -Cold- Conducts
Hot- Isolates
-What is autoignition and what does it sense? - -Ensures instantaneous igniton if an engine
loses power. Senses Torque, Oil Pressure, and loss of Compressure dischatge pressure
-What positions are fail type anti-ice valves in? - -Powered closed and spring loaded open
-What instrument indication would you most likely see when engine anti-ice is turned on?
- -Slight Rise in EGT (10 Degrees)
-Starting sequence - -Starter, Ignition, Fuel
-When do you disengage the starter? - -When it reaches self accelerating speed
-Where is the Pressure Regulating and Shutoff valve located? - -Pneumatic starter Unit
-What does the PRSV do? (Pressure Regulating, and Shutoff valve) - -controls airflow to
the pneumatic starter
-What parameter is the most critical to observe? - -TIT
-What indicates a successful start on a turbine engine? - -Rise in EGT
-At what RPM is a stall most likely to occur? - -Low-Medium
-When are the bleeds open? - -at Low power
-What if the bleeds are open @ High power? - -High EGT is expected