What does PSU stand for in the context of aviation?

In the context of aviation, "PSU" stands for Passenger Service Unit. This term refers to the components located above the passenger seats in an aircraft that provide essential services to the passengers. These units typically include the reading lights, air vents, and oxygen masks.

Understanding the role of the Passenger Service Unit is crucial for cabin crew as it directly impacts passenger comfort and safety during a flight. For instance, in emergency situations, knowing how to access and operate these units can ensure that passengers receive timely assistance, such as access to oxygen when necessary.

The other options, while they sound plausible, do not accurately define PSU in aviation terminology. "Passenger Seat Usage" relates more to seat booking and management rather than onboard services. "Passenger Safety Unit" is not a standard term used in aviation discourses, and "Public Service Unit" generally refers to broader public utility services unrelated to individual flight operations or passenger care.