15.21 OPERATION AND MONITORING👌🏼 Flashcards
As engine speed increases what happens to fuel
Increased fuel supply
Where should the aircraft be positioned
Into the wind
The aircraft must be clear up to what distance
10 metres
Electrical power must be applied as well as external ground air which is what in psi
40-55psi
Fuel should only be introduced when
Correct engine speed reached
Why should EGT be monitored during engine run
- to ensure maximum start temperature is not exceeded
Why should engine power not be increased above idle more than absolute necessary
-operational life is shorter
Usually on wing-mounted engines, should both engines be on
Yes
When carrying out acceleration checks what do we use as the datum
Oldest engine on the aircraft to ensure engines will accelerate at the same rate
When an engine has operated at idle or high power levels it should be left to cool for how long
5 minutes
When an engine has operated at idle or high power levels it should be left to cool for how long
5 minutes
Why is a cool down time necessary during shutdown purposes
- prevent possible seizures of rotors
What indications are used for engine monitoring
- EPR
- Rotor speed (N1, N2 and N3)
- Fuel flow
- exhaust gas temperature (EGT)
What does the EPR give
Indication of thrust output
Which spool gives more thrust
- N1
Explain fuel flow indication
- monitor fuel consumption during flight
- trend monitoring purposes
If EGT exceeds red line what must happen
Inspection of the critical engine are required
What is used to indicate power developed by turbo prop and turbo shaft engines
- Torque monitoring systems
How is torque displayed in flight deck
- torque oil pressure
- torque percentage
- direct horse power read out
What instrument is used to indicate torque
- torque meter
Explain hydro mechanical sensing system
- ## converts engine oil pressure to torque signal
Explain electronic sensing systems
- converts twist of the power output shaft into a torque signal
Explain phase displacement
Shaft that consist of 2 shafts with a phonic wheel
The data recording on board the aircraft is performed by ?
Aircraft condition monitoring (ACMS)
Engines with hydro-mechanical fuel controls need an additional computer for what reason
- parameter measurement (Power plant data multiplexer) (PMUX)
What does the Data management unit (DMU) do and where is it located
- Records the data and complies the ACMS report
- located in aircraft
ACMS reports are used when
- routine reports
-request reports (e.g. flight crew) - advisory reports
During how many take offs is a ACMS report generated
4
Cruise report is generated after how many take offs
35 take offs
If the engine results are critical what occurs
Critical warning for Maintenance engineers is triggered
Magnetic particles are divided into 4 primary groups
- swarf
- magnetic fines
- metal flakes
- chip
What colour is the sludge by magnetic fines
Black sludge
What is the boroscope inspection for
- internal visual inspection of engine
Modern engines use what to detect engine vibration
Piezoelectric accelerometers
Work of any blade damage must be carried out by?
- hand (using files)(emery cloth)
Where are metal flakes found from
- ball bearings, gear teeth etc
Where are accelerometers fitted
To fan or LP casing and turbine casing
How are carbon deposits from nozzle cleaned
By approved cleaning fluid
How to remove softened carbon deposits
- with soft bristle brush
Why would you perform a compressor wash
- to get rid of contaminants that reduces efficiency
In the turbine, contaminants takes the form of what
- sulfidation (build up of sulphur deposits from burning fuel)
What is used to rinse compressor if the major cause of contamination is salt ingestion
- fresh water
Explain desalination wash
- using fresh water to rinse while running engine at idle speed.
- Or while motoring the engine over on the starter
