Page 263 - The Jet Engine

Maintenance

Fig. 24-1 A typical maintenance schedule (extracts).

their own and associated component operation. Any video photography which may be linked to closed
fault detected is recorded in its built-in memory for circuit television. These instruments are used for
subsequent retrieval and rectification by the ground examining and assessing the condition of the
crew. On aircraft that feature electronic engine compressor and turbine assemblies, nozzle guide
parameter flight deck displays (Part 12) certain faults vanes (fig. 24-2) and combustion system, and can be
are also automatically brought to the flight crew's inserted through access ports located at strategic
attention. points in the engine main casings.

Ground indicators 18. The engine condition indicators include
16. The devices used or checked on the ground, as magnetic chip detectors, oil filters and certain fuel
distinct from those used or checked in flight, may filters. These indicators are frequently used to sub-
conveniently be referred to as ground indicators; this stantiate indications of failures shown by flight deck
title is also taken to embrace instruments used for
engine internal inspection. monitoring and in-flight recordings. For instance,
inspection of the oil filters and chip detectors can
17. Internal viewing instruments can be either reveal deposits from which experienced personnel
flexible or rigid, designed either for end or angled can recognize early signs of failure. Some
viewing and, in some instances adaptable for still or maintenance organizations progressively log oil filter

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