Pratt & Whitney Rzeszów S.A.
MAINTENANCE MANUAL
PZL-10W ENGINE
2015.12.30
72-02-00
Page 31
Export Control Classification: PL/UE 9E999
5. Time Between Overhauls (service life) of PZL-10W engine.
A. The engine TBO (Time Between Overhaul) is the engine usage period after which the engine
operation shall be discontinued, disregard of its technical condition.
The engine usage period is limited by: number of “start-stop” cycles, engine operation time and
calendar operating period.
The TBO for the engine and its accessories is specified in the engine log-book, in which the following
details are shown as applicable for given engine and operation period:
(1) Allowed total engine operation time since the beginning to the end of operation, both on the
ground and in the flight.
(2) Allowed number of cycles, which is a sum of "start-stop” cycles (excluding the unsuccessful,
false, and cold starts).
(3) Allowable maximum one-time and accumulated operating time at TAKE-OFF rating.
(4) Allowable maximum one-time and accumulated time at 30 min. OEI rating and limitation of
number of events this OEI rating and is applied.
(5) Allowable maximum one-time and accumulated time at the 2.5 min. OEI rating and limitation of
number of events this OEI rating is applied.
(6) The calendar period of service (operation) before the next overhaul.
B. Values of TBO (service life) of PZL-10W engines.
(1) The TBO of PZL-10W engines of series 1 and 2 to the first overhaul and then after subsequent
overhauls is 1500 hours / 2250 start/stop cycles.
The calendar period of operation is 8 years.
(2) The TBO of PZL-10W engines of series 3 to the first overhaul is 3000 hours / 4500 start/stop
cycles. After subsequent overhauls, the TBO is 1500 hours / 2250 start/stop cycles.
The calendar period of operation is 8 years.
(3) The TBO limitations for all engine series are given in Service Bulletin no. E-19W169/F/2016.
NOTE: The engines directed to operation (new and after overhaul) always have installed the life-limited
parts and assemblies with sufficient life margin which ensure that engine can be operated during
whole TBO period given in log-book.
All individual departures from this rule are recorded in log-book or given in appropriate bulletins
issued by the engine manufacturer. During the engine overhaul replaced are: life-limited parts
and assemblies, parts classified during inspection as worn out and not reusable parts. All
overhauls are carried out by the engine manufacturer or by an authorized overhaul facility.