Technological advances have meant the complexity of aircraft is constantly increasing; the number of systems on-board that all need to be integrated and considered. Having worked on multiple aircraft types, from new technology jets to aging passenger aircraft, it is clear that so many systems are relied upon to fly the latest aircraft. This will only increase with unmanned aircraft.
From an engineering perspective, there are therefore more and more considerations to design and maintain aircraft. Working on the latest jet aircraft required significant training to understand all of the supporting aircraft systems. Faults were often software or computer based, rather than classic mechanical failures of components and materials.
As an aerospace engineer, you need to understand what the implications of individual and collective failures are to understand the risk to the aircraft.
A recent example of challenges with increasingly complex aircraft is the grounding of the 737 Max.