Which facility initiates Search and Rescue procedures when no flight plan has been filed?

The correct answer identifies the Flight Service Station (FSS) as the facility that initiates Search and Rescue (SAR) procedures when no flight plan has been filed. FSS plays a crucial role in assisting pilots, especially in areas where air traffic control may not have oversight or when pilots are flying VFR (Visual Flight Rules) without filing a flight plan.

In situations where an aircraft is unaccounted for and no flight plan exists, the FSS is responsible for alerting the appropriate search and rescue authorities. They monitor for signs of overdue aircraft and can initiate reports to search and rescue entities when necessary. This process ensures that aircraft in distress can be located and assisted promptly.

While other options, such as the ATC Center, Airport Operations, and Coast Guard, have their own roles in aviation safety and rescue efforts, they may not be the primary initiators of SAR procedures under the specific condition of an unfiled flight plan. The ATC Center primarily manages traffic and coordinates with flights that are under their jurisdiction, while Airport Operations handle matters specific to airport facilities and operations. The Coast Guard is principally concerned with maritime rescue and may be involved in search and rescue operations for aircraft only in specific scenarios where their jurisdiction overlaps.