MCA COC Cheat Sheet 2026

The 30 highest-yield MCA COC facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. What type of fire extinguisher should NEVER be used in a machinery space on board ship? → Water extinguisher — risk of electrical shock and steam explosion near hot machinery
2. Which record must be maintained on board a SOLAS vessel as a mandatory GMDSS compliance requirement? → A radio log recording all distress, urgency, and safety communications
3. A vessel displacing 10,000 tonnes has KM = 8.5 m and KG = 7.2 m. A weight of 500 tonnes is shifted vertically upward by 4 metres. What is the new GM? → 1.10 metres
4. During the 'Appraisal' stage of passage planning, which of the following actions is the primary focus for the navigating officer? → Gathering and considering all relevant information for the intended voyage.
5. A vessel has a negative initial metacentric height (GM) when upright. What is the resulting condition of the vessel called? → Angle of loll
6. A vessel has several slack double-bottom tanks. What is the primary effect of the free surface of the liquid in these tanks on the vessel's stability? → A reduction in the righting arm (GZ) at all angles of heel.
7. In the Northern Hemisphere, according to Buys Ballot's Law, if you stand with your back to the wind, where is the centre of a low-pressure system located? → To your left and slightly ahead
8. Under the MCA's Seafarer Training and Certification requirements, what is the minimum standard of fire-fighting training required for all seafarers? → Basic fire prevention and fire-fighting (STCW A-VI/1) as part of basic safety training
9. Under GMDSS, what is the minimum number of VHF radiotelephone installations required on a SOLAS vessel on an international voyage? → Three, of which at least two must be portable handheld units
10. According to SOLAS requirements, how often must abandon ship drills be conducted on board a UK-flagged cargo vessel? → Every month
11. What is the role of an MRCC in the GMDSS distress system? → To receive distress alerts and coordinate search and rescue operations
12. Which VHF channel is exclusively designated for DSC distress alerting under GMDSS? → Channel 70
13. What lights must a power-driven vessel of 50 metres or more in length display when underway at night? → Two masthead lights (fore and aft), sidelights, and a sternlight
14. On a UK-flagged passenger ship, what is the regulatory requirement for the frequency of abandon ship and fire drills? → Weekly for both drills.
15. Under the MCA's stability criteria (based on the IMO Intact Stability Code), what is the minimum required GM for a cargo vessel in the departure condition? → 0.15 metres
16. What is a primary advantage of using a semi-balanced rudder compared to a fully unbalanced rudder? → It requires less torque from the steering gear to operate.
17. While navigating at night, you observe a vessel ahead displaying three all-round red lights in a vertical line. What does this indicate? → A vessel constrained by her draught.
18. What is the 'MAYDAY' equivalent for a vessel on fire at sea? → MAYDAY on Channel 16 — fire is a distress situation requiring immediate assistance
19. In which GMDSS sea areas is a satellite EPIRB mandatory for SOLAS vessels? → A3 and A4
20. Under the MCA's requirements, what is the minimum period of validity for pyrotechnic distress signals carried on board before they must be replaced? → 3 years from date of manufacture
21. According to the LSA Code, what is the minimum capacity required for a lifeboat on a cargo ship? → Sufficient to accommodate the total number of persons on board on each side of the ship
22. Under Rule 15 of the COLREGs, when two power-driven vessels are crossing so as to involve risk of collision, which vessel is the give-way vessel? → The vessel which has the other on her starboard side
23. What frequency does the international NAVTEX service use to broadcast Maritime Safety Information? → 518 kHz
24. What information is automatically encoded in a DSC distress alert transmitted by a GMDSS-equipped vessel? → MMSI, nature of distress, position, and UTC time of position
25. What is the primary purpose of an EPIRB? → To transmit a distress signal and vessel position to SAR authorities via satellite
26. In accordance with Rule 9 (Narrow Channels), which of the following actions is required for a vessel of less than 20 metres in length? → Not impede the passage of a vessel which can safely navigate only within the channel.
27. What action does COLREGs Rule 16 require of the 'give-way' vessel? → Take early and substantial action to keep well clear of the stand-on vessel
28. According to UK regulations implementing SOLAS Chapter III, emergency drills for enclosed space entry and rescue must be conducted at intervals not exceeding: → Every two months.
29. A vessel's compass reads 045°C and deviation for the heading is 3°W. What is the Magnetic heading? → 042°M
30. Which four sea areas are defined under the GMDSS? → A1, A2, A3 and A4