Which line is associated with COORDINATING ALTITUDE?

• A. Line O
• B. Line P
• C. Line N
• D. Line M

Answer: (A)

Coordinating altitude is the reference height used to align all elements in a joint operation so everyone operates at the same vertical level. On the chart, each line serves a specific vertical role, and the line that represents coordinating altitude is the one specifically marked for that purpose. The line labeled O corresponds to that coordination role, and its path through the diagram matches the altitude level designated for coordination in the chart’s legend or notes. This makes it the correct reference when you’re asked which line is associated with coordinating altitude.

The other lines in the diagram represent different altitude constraints or references, but they are not designated as the coordinating altitude, so they don’t carry that same reference for synchronization.