Actually, the International Aeronautical and Maritime Search and Rescue (IAMSAR) Manual officially consists of only three volumes
. This is the most famous volume, carried on ships and aircraft. It tells the story of the "On-Scene Coordinator" (OSC)—the captain or pilot who arrives first and must take charge, launch lifeboats, and communicate with the distressed craft. Why you might see "Volume 4" references: iamsar volume 4
If you are following the "story" of how the global SAR system works through its intended volumes, it typically flows like this: The "Story" of the IAMSAR System Why you might see "Volume 4" references: If
. There is no official "Volume 4" published by the IMO or ICAO; however, some regional frameworks or national plans (like the Asia/Pacific SAR Plan ) are currently in their Version 4.0 , which might be the source of the confusion. International Civil Aviation Organization and communicate with the distressed craft.