Maintenance Fundamentals, Publications & Drawings Flashcards
The two types of maintenance activities
Scheduled and Non-Scheduled
Fixed Life or hard life
is where the maintenance interval is defined, after
this time it must be overhauled or scrapped
On Condition
where the life is dependent on the condition of the item as
observed at regular periodic inspections.
Condition Monitored
which relies on routine surveillance and evaluation
of the system and/or component performance and failure rates.
Maintenance Periods
Calendar Time
Maintenance carried out on a calendar schedule, examples are: Daily, weekly,
monthly or yearly. Other calendar schedules could be dates, e.g. No later than
25/12/2017 or 6 months from date of issue.
Maintenance Periods
Airframe Hours
Airframe or “Flight Hours” are normally calculated and recorded on a “Take-off” to
“Touch -down” basis. These are normally recorded by the flight crew and added to
the previous flight hours
Maintenance Periods
Flight Cycles
The number of cycles completed by the airframe is equal to the number of aircraft
landings.
Maintenance Periods
Operating Hours
The time measured from when an engine, component or unit begins to operate; until the operating unit completes its operation or unit. This can be especially important for monitoring the actual usage of components, such as engines and avionics equipment, which are operating for much longer than “Flight time”.
Service Check
Every calendar 48 hours
Exterior visual checks.
Routine aircraft
servicing, such as
checking hydraulic
fluids, engine oil &
general lubrication
A Check
Every 125 flight hours
Exterior visual checks.
Check
Routine and specific
aircraft inspections.
Replacement of time-
limited items.
B Check
Every 3 months
Includes A Check
items, plus calendar
items.
C Check
Required every 24 months or no more than 4000 flight hours from the last
C Check, whichever occurs first.
Includes A and B Check items.
Detailed inspections of the aircraft, components, engines,
and appliances.
