The APU includes an engine, control system, starting, fuel, lubrication, fire protection, intake and exhaust arrangements.
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APU
APU Abbreviation · Auxiliary Power Unit Synonym
Auxiliary Power Unit: a small gas turbine that can provide aircraft power and starting support.
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How the term is used
APU capability depends on aircraft design and operating phase. Typical functions include ground electrical supply, engine starting support and air-conditioning air, with limits controlled by aircraft systems and procedures.
Where you may encounter it
Maintenance may involve fault messages, oil servicing, inspections, starting-system checks and performance monitoring.
APU intake, exhaust, fire and high-temperature hazards require strict approved precautions.
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