The strategy or maintaining a new aircraft is a relatively straightforward challenge. However, over time, various different options begin to present themselves, and the older an aircraft gets, the more complex those options become. Questions arise regarding the merits of proactive as opposed to reactive maintenance, the use of used serviceable materials (USM) as opposed to brand-new OEM parts, whether repair or replacement of parts is a better option, and at what point should maintenance be aligned with any plans ...