What is one of the primary causes of wear and tear on an APU?

Overheating due to inadequate cooling is indeed one of the primary causes of wear and tear on an Auxiliary Power Unit (APU). An APU generates a significant amount of heat during operation, and it relies heavily on an effective cooling system to maintain optimal operating temperatures. If the cooling system is inadequate—whether due to design flaws, failure of cooling components, or external factors—the temperature within the APU can rise beyond safe limits.

This overheating can lead to several detrimental effects, including thermal degradation of materials, increased friction in moving parts, and accelerated wear of critical components such as bearings and turbines. Over time, this can significantly reduce the lifespan and reliability of the APU, leading to potential failures and costly repairs. Proper maintenance of the cooling system and monitoring of temperature levels are essential to prevent overheating and ensure the longevity of the APU.