🔍 Key Concepts
• International Code of Signals (INTERCO) procedures for flashing light communication
• Use of repetition and verification groups in visual signaling
• Special two-letter groups like AA, AB, RQ, WA, CS, RPT and how they function
💭 Think About
• Think about what AA and AB are doing in a flashing light conversation: are they asking, answering, repeating, or correcting?
• Which of the listed groups is most logically paired with something that might come in a sequence like AA, AB…?
• In procedural codes, which group is typically associated with repeating or requesting a repeat, and which with starting or acknowledging a message?
✅ Before You Answer
• Check in a signaling manual how AA and AB are defined when used with flashing light (are they repeat markers, word spacers, or something else?).
• Verify which of the options (CS, RQ, RPT, WA) is itself a procedural signal rather than a general question or word signal.
• Confirm that the group you choose is actually used together with AA and AB in a set, not just elsewhere in the code.