15.21 Flashcards
What are the types of servicing
Scheduled and Unscheduled
When all engine are stabilised what must you check for?
Oil pressure & temperature, EGT & RPM (N1,N2(&N3)), fuel flow, vibration and EPR
What does AIDS stand for
Aircraft Integrated Data Systems
What must you switch off at IDLE rpm
Start and ignition
What does the EPR indicate
The thrust output
What does torque monitoring systems indicate in the flight deck
Power developed by the turbo-prop or turbo shaft engines
Centrifugal compressor engines measure engine power by comparing what
Engine rpm and jet pipe temperature
What does DMU sand for and what dose it do?
Data Management Unit, records the data and makes it into a ACMS report
What are the accelerations measured in
Inches per second and millimetres per second
How many accelerometer are fitted in an engine and where are they located?
2 are fitted,
One is fitted on the fan or LP casing
The second one is fitted to the turbine casing
What can the engine performance and limitations indications be classified into ( 3 groups)
~ performance monitoring
~ system monitoring
~ condition monitoring
What does EGT stand for
Engine gas temperature
What must you do when the EGT passes the red line
Inspections are demanded
After engine run how long should you keep the engine on ideal before closing the HP cock
3 minutes
What is Hard time
Removal of intense for overhaul pr replacement at specified intervals
What do modern engines use to detect engine vibration
Piezoelectric accelerometers
After gaining clearance from ground crew to start the engine what must you do next
Close throttle and HP cock
Before working on the gas turbine engine, what must you check prior to positioning the aircraft
The logbook
When the engines are running, what else can you carry out if required
Engine trimming
Why can you not use methanol during compressor cleaning with water at low temperature
It can damage the titanium
What can FOD cause in the engine
Hard rubs
What does TBO stand for
Time Between overhaul
What must you do when we get a LP rotation indication
Open HP cock
What is on condition
Process which involves the inspection,test or checking of particular items at specified periods to ensure they remain in service
How much clearance distance should the aircraft have in front of the engines
10 meters
What is a desalination wash
Using fresh water to wash the compressor
What are the three main methods of conditioning monitoring
Flight deck indicators
In flight recorders
Ground indicators
What are the 3 maintenance processes that the CAA recognise
~ Hard time
~ On-condition
~ Condition Monitoring
What re the most common used sensing systems for torque monitoring
Hydro mechanical ( engine oil pressure —> torque signal)
Electronic ( twist of the power O/P shaft —> torque signal )
What system on board the aircraft records the data of the engine condition
Aircraft condition monitoring system (ACMS)
What does JPT stand for
Jet pipe temperature
At what speed can you carry out engine adjustment
Ideal rpm
What ways can torque be displayed in the cockpit
~ torque oil pressure
~ torque percentage
~ direct horse power dead out
What is the EPR
Ratio of the jet pipe pressure:compressor inlet pressure
What is condition monitoring
Not a preventative process, info gained from operational experiences is collected
What does MCD stand for
Magnetic Chip Detector
What is trimming?
Term applied to idle speed, various throttle setting and maximum thrust adjustment during engine performance testing
Engine torque is proportional to what?
Horse power 🐴
What must you use when cleaning the compressor in low temperature conditions with water
Isopropyl alcohol as an anti freeze
