What do you enter in block 26 of the initial flight progress strip for search and rescue use?

In block 26 of the initial flight progress strip for search and rescue operations, the pertinent information to provide is the sector position number. This number is vital for coordinating and identifying the specific area in which the aircraft is operating, especially in emergency situations where rapid response and accurate location data are crucial.

The sector position number helps air traffic controllers and search and rescue teams quickly connect the aircraft with the appropriate operational area, facilitating efficient communication and response times. It is an essential reference for ensuring all personnel involved in the rescue can identify the aircraft's location and status.

While other options may include valuable information, they do not serve the specific purpose of indicating the position relevant to search and rescue operations. For instance, flight plan numbers are useful for tracking flight details, but they do not pinpoint the sector of operation as effectively as the sector position number. Similarly, call sign information is important for identification but lacks the geographical context needed for search and rescue. Lastly, the pilot's last name may not be necessary for the immediate operational needs in emergencies. Thus, the correct entry in block 26 is the sector position number to enhance the efficiency and effectiveness of search and rescue efforts.