Which of the following MMSI numbers...

Which of the following MMSI numbers indicates a U.S. flag ship station?

🔍 Key Concepts

• MMSI (Maritime Mobile Service Identity) structure and what the first three digits represent • The specific MID (Maritime Identification Digits) assigned to the United States • Difference between leading zero(s) and the core 3‑digit MID in ship station numbers vs. other types (like coast stations, group calls, etc.)

💭 Think About

• Look at the first three meaningful digits of each MMSI. Which one corresponds to the U.S. MID? • Consider how a standard 9‑digit ship station MMSI is built: it starts with the country’s MID, then vessel‑specific digits. Which options match that format for a U.S. ship? • Ask yourself: which of these numbers looks like it might belong to another country’s MID (e.g., Europe, Asia, etc.), not the United States?

✅ Before You Answer

• Verify the official U.S. MID(s) used for ship stations (from current ITU/USCG resources). • Confirm that a ship station MMSI is exactly 9 digits and begins directly with the 3‑digit MID (no extra leading digits for ships). • Eliminate the choices whose first three digits are clearly assigned to non‑U.S. countries once you know the correct U.S. MID.