Onboard Maintenance System Q’s Flashcards
Fatigue fuses used in structure monitoring
Are bonded to the structure and fail at different fatigue stresses
A HUMS in a helicopter is
A system which monitors time period of components in service and warns of a premature failure
A MCDU is
To dialog with the CMC
A modern aircraft CMC used
A CRT screen
A red line shows on a thermal sensitive airborne printer paper this indicates
The printer roll needs replacing
Aircraft condition monitoring monitors
Certain parameters
Aircraft normally fitted with 2 cmc and you only have one to dispatch the aircraft
Where do you fit it
LH side
An aircraft condition monitoring system
Stores information for long term error analysis
BITE fitted to onboard maintenance systems can be
Start up interruptive and continuous
Central maintenance system considers the eicas warnings cautions and advisory messages as
Flight deck effects
HUMS failure has what effect
No indication until data is downloaded
In a CMC aircraft flight deck indications and warnings are managed and provided by the
Electronic interface units
In CMC warning signals are generated by
Warning computer
In a modern aircraft a bite is carried out
Continuously when the systems are working
In an autoland aircraft fitted with a CMC
All faults are recorded in non volatile memory
In case the aeroplane is wired for dual installation of the CMC and only one computer is to be installed
It must be installed on LH side
Maintenance messages
Are not made available to the crew
MCDUs
Enable dialog with the CMC
On an aircraft fitted with a CMC how do you get to the system pages
Through the ground test function
One of the inputs in a cmc is autopilot controls the data will be stored in
Non volatile memory
Power to the CMC is from the
Standby AC bus
The basic structure for the data chain for the onboard maintenance system for most aircraft compromises
System computer to central computer to graphics generator to flight deck displays
The CMC
Can be used to simulate aircraft in the air
The flight phases in the CMC start at
Power on
The purpose of ACMS is to
Detect the source of a fault
The real time on a cmc is when
Existing faults page is selected on the CDU
The uploading function on an onboard maintenance system enables
The onboard data base to be updated
What devices aids structural monitoring of aircraft
Electrical strain sensors
What deceive is required to load software or install updated software to the FMC
Data loader
What does the expression electronic flight library system refer to
A system of cd or disc data that lists all data configs and systems for that aircraft aircraft and carried on board
What is most appropriate for maintenance data
Data at maintenance base provided in real time
What is one reason for structural monitoring
To develop a preventative maintenance policy
What is provided by the CMC fitted to
Modern aircraft
A centralised location for aeroplane fault information
What is the reason for dual cmcs being fitted
Redundancy protection
What is the name given to sensors that convert mechanical energy into electrical energy by the force exerted on a crystal pile which are utilised in structural monitoring
Piezo device
What type of memory do CMCs have
Non volatile
Hat unit in a HUMs system carries out the data acquisition
DAU
Where are modern aircraft printers located
Centre pedestal
Where are the CMC accessed from
Flight station CDUs
Why are modern aircraft fitted with printes
To print faults recorded by the CMC to aid in rectification
With a ACMS quick access recorder
The tape can have used previously if it is first bulk erased
With OBM systems the purpose of CMF is to
Log relavent maintenance data
For aircraft with dual CMCs when only one CMC is available it
Must be connected to the left side
