How can environmental considerations affect APU operation?

Environmental considerations significantly influence APU operation, particularly in extreme temperature conditions. When temperatures fluctuate, they can affect fuel combustion characteristics, lubrication, and overall engine performance, thereby impacting fuel efficiency. In extremely cold conditions, fuel may not vaporize properly, leading to incomplete combustion. Conversely, high temperatures can lead to overheating and increased wear.

As a result, adjustments to APU operation may be necessary to ensure optimal performance and efficiency. These adjustments could involve modifying fuel flow rates or altering operational procedures to accommodate changing inefficiencies. Understanding these environmental impacts is crucial for maintaining the APU's reliability and operational readiness in varying climatic conditions.