MSAP: COLREGS and Anti-Collision Questions

Vessels Restricted in Ability to Maneuver

• A vessel transferring provisions while underway restricts its navigational ability to change course.
• A vessel in a towing operation that restricts the navigational ability of the mark vessel and her tow to change their course.
• A vessel whose anchor is fouled.
• A vessel engaged in dredging.
• A vessel engaged in launching or recovering a mine-clearing aircraft.

Vessels Not Under Command

• A vessel transferring provisions while underway.
• A vessel in a towing operation that restricts the navigational ability of the mark vessel and her tow to change their course.
• A vessel whose anchor is fouled.
• A vessel engaged in dredging.
• A vessel engaged in launching or recovering a mine-clearing aircraft.

Vessel Constrained by Draft

• A power-driven vessel severely restricted in its ability to deviate from its course due to its draft in relation to the available navigable water.

COLREGS Lights

• Authorized light used to assist in the identification of submarines operating on the surface is an intermittent flashing blue light.

Good Seamanship

• Practicing good seamanship involves using radar and fog signals, and proceeding at a speed that allows for taking advantage of a favorable current in a fog.

COLREGS Overtaking

• When a power-driven vessel is overtaking another vessel, it should sound one short blast and alter course to starboard.

COLREGS Sailing Vessels

• A sailing vessel becalmed or with restricted maneuverability is not "not under command".
• A vessel engaged in underwater operations or a difficult towing operation is considered "not under command".

Inshore Traffic Zones

• Inshore traffic zones shall not be used by vessels that cannot safely use the lane within the zone.

Anchoring in a Narrow Channel

• Anchoring is not permitted in a narrow channel.

COLREGS Fog Signals

• A vessel hearing a fog signal forward of the beam should take action to prevent a collision.

COLREGS Collision

• After a collision, the master should not always attempt to make a substantial course alteration.

COLREGS Traffic Separation Schemes

• A vessel engaged in fishing should not impede the passage of a vessel following a traffic lane.
• A vessel of less than 20 meters in length or a sailing vessel should not impede the safe passage of a vessel following a traffic lane.

COLREGS Whistle Signals

• The Government of any State can make provision for special rules allowing the use of additional whistle signals between vessels.

COLREGS Lights and Signals

• The sidelights of a power-driven vessel should be placed at a height above the hull of not less than 1.5 meters or not greater than 4.5 meters.
• Additional signals for fishing vessels should be visible all around the horizon at a distance of at least 1.0 nm.
• If two masthead lights are carried for a power-driven vessel, the after one should be vertically higher than the forward one by at least 0.5 meters.

Test your knowledge of COLREGS (International Regulations for Preventing Collisions at Sea) and anti-collision procedures with this quiz. Identify the authorized lights for submarines operating on the surface and understand the concept of 'good seamanship' as required by the regulations.