What does J/S stand for in the context of aircraft seating?

In the context of aircraft seating, J/S stands for Jumpseat. The jumpseat is a special seat on an aircraft primarily designed for pilots, flight attendants, and occasionally other authorized personnel who are working or riding in the cabin but not in a passenger capacity. It allows crew members to be seated safely while still providing access to perform their duties or monitor the cabin.

Jumpseats are often located in the flight deck or in the cabin and are utilized on a voluntary basis by crew members during non-operational flights. This terminology is widely used in the aviation industry to refer to the designated seating for crew members, differentiating it from regular passenger seats. Understanding this term is crucial for proper communication and operations within airline environments.