5
Permissible Tolerances
The following paragraphs outline the permissible tolerances that can be applied to the interval of the tasks listed in
the Time Limits and Scheduled maintenance sections. The tolerance is not cumulative.
It is the responsibility of the owner or operator to make sure that any maintenance interval extension is accepted by
the local Airworthiness Authority of the country of registration of the affected aircraft.
The owner or operator is responsible for complying with all national regulations.
5.1
Flying Hour Based Intervals
The tolerance permissible for the flying hour based intervals is ±10%, but not more than 500 FH.
5.2
Calendar Time Based Intervals
The tolerance permissible for the calendar time based intervals is ±10%, but not more than 6 months.
The subsequent monitoring procedure for all the calendar time limited items after their initial replacement or
inspection, will be in installed or elapsed time. Each task with a calendar time is understood as installed time unless
stated as “elapsed”. This applies to tasks in Chapter 4 and Chapter 5.
5.3
Landing Based Intervals
The tolerance permissible for the landings based intervals is ±10%, but not more than 500 landings.
5.4
Examples
If you do an inspection inside the permitted tolerance, the planned inspection times do not shift. Two examples
have been provided for reference:
−
The 300 FH inspection package can be accomplished any time between 270 FH and 330 FH (±10% or ±30
FH). The next inspection is still due at 600 FH (±30 FH). The inspection intervals do not change
−
The 12 months inspection package can be accomplished any time between 11 months and 13 months (±10%
or 1 month). The next inspection is still due at 24 months (±1 month). The inspection intervals do not change.
If you do an inspection earlier and outside the given tolerance, then the planned inspection time will shift, examples
shown below:
If you do the 300 FH and the 300 FH / 12 Months inspection packages earlier and outside the given tolerance,
for example at 150 FH (2 months of operation), the inspection interval shifts. In this case the following inspection
is due at 450 FH (6 months of operation) with a ±10% or ±30 FH tolerance since only the 300 FH and the 300
FH / 12 Months inspection packages are due. However, the next inspection would then be at 600 FH (8 months of
operation) where only the 600 FH and the 600 FH / 12 Months inspection packages are due and as a result, ±10%
or ±60 FH tolerance can be applied. If the operation continues like this, at 1800 FH (24 months of operation) the
600 FH, 600 FH / 12 Months, 1200 FH / 12 Months and 2400 FH / 24 Months inspection packages will be due with
a ±10% or ±60 FH tolerance. The tolerance for the inspection is always driven by the inspection package that is
due with the lowest interval. The tolerance can be calendar time driven, if the inspection package calendar time
interval is reached first.
PC-12/47E AMM Doc No 02300, ISSUE 01 REVISION 27 MSN 545, 1001-1719, 1721-1942
12-B-AM-00-00-00-I
UNCLASSIFIED
Effectivity: All
12-B-05-00-00-00A-018A-A
UNCLASSIFIED
19.11.2019 Page 4
