Coast Guard Test Coast Guard Communications 2 — Questions and Answers
Question 1: What is an MMSI number and why is it important?
- A 9-digit Maritime Mobile Service Identity used to identify a vessel in DSC and AIS transmissions (Correct answer)
- A vessel registration number issued by each state
- A radio operator license number
- A GPS coordinate identifier for vessel tracking
Correct answer: A 9-digit Maritime Mobile Service Identity used to identify a vessel in DSC and AIS transmissions
An MMSI is a unique 9-digit number assigned to a vessel's radio, used in DSC distress calls and AIS transmissions, allowing the Coast Guard to identify the vessel instantly.
Question 2: What is AIS and what information does it broadcast?
- Automatic Identification System; broadcasts vessel identity, position, course, speed, and other data (Correct answer)
- Automated Inspection System for vessel safety
- Aerial Identification Signal for aircraft coordination
- Automated Intelligence Surveillance for harbor security
Correct answer: Automatic Identification System; broadcasts vessel identity, position, course, speed, and other data
AIS (Automatic Identification System) automatically broadcasts a vessel's identity, position, speed, course, and other data to nearby vessels and shore stations.
Question 3: When is a ship station radio license required for a US vessel?
- When the vessel travels to foreign ports, carries more than 6 passengers for hire, or is required by federal law (Correct answer)
- For all vessels with a VHF radio
- Only for vessels over 100 feet
- Never — licenses are voluntary in the US
Correct answer: When the vessel travels to foreign ports, carries more than 6 passengers for hire, or is required by federal law
A ship station license is required for US vessels operating in foreign waters, carrying passengers for hire, or when otherwise required by law; pleasure boats in US waters only are generally exempt.
Question 4: What is the purpose of the Global Maritime Distress and Safety System (GMDSS)?
- To ensure vessels can send and receive distress alerts and safety information worldwide (Correct answer)
- To regulate commercial radio operators
- To provide satellite navigation to all vessels
- To monitor vessel fuel consumption globally
Correct answer: To ensure vessels can send and receive distress alerts and safety information worldwide
GMDSS is an internationally agreed-upon set of safety procedures, equipment, and communication protocols ensuring that distress alerts and safety information reach rescue authorities worldwide.
Question 5: What radio watch must all vessels equipped with a VHF radio maintain while underway in US waters?
- Continuous watch on Channel 16 (Correct answer)
- Watch on Channel 22A only
- Watch on the working channel only
- No mandatory watch required
Correct answer: Continuous watch on Channel 16
Federal regulations require all vessels equipped with VHF radios to maintain a continuous watch on Channel 16 while underway, except when actually communicating on another channel.
Question 6: What does 'radio silence' mean in an emergency?
- All stations must cease transmissions that could interfere with a distress message in progress (Correct answer)
- All radios must be turned off
- Only the Coast Guard may transmit
- Only vessels near the emergency may transmit
Correct answer: All stations must cease transmissions that could interfere with a distress message in progress
When a MAYDAY is in progress, the controlling authority may impose radio silence (SEELONCE MAYDAY), requiring all other stations to stop transmitting on that frequency until released.
Coast Guard Test Coast Guard Communications 2
What is an MMSI number and why is it important?