Navigational Safety

Navigational Safety

The principal deep water navigational channels within the statutory limits of the port of Southampton are well marked by buoys and lights. These channels are in constant use by commercial vessels, including large deep-draught tankers (VLCCS), container ships, ferries and other traffic.

Recreational users of the harbour are advised to keep well clear of these main channels whenever possible, and use the recommended crossing areas.

When main channels have to be crossed, this should be done as nearly as practicable at right angles.


Large container ships and VLCCs, in particular, have very restricted visibility for quite a distance ahead when carrying a deck cargo of containers. You maybe be able to see her clearly, but can she see you? Most recreational sailors take a justifiable pride in the responsible way they conduct themselves. Part of this is a

realisation that hindering passage of large commercial vessels is not only bad manners but dangerous to themselves, their crews and the ship itself.

Recreational users of the port area are particularly requested to remind themselves of and observe, the Collision Regulations, Port of Southampton Byelaws and Local Notices to Mariners.

Speed of Vessels

Southampton Harbour Byelaws prohibit the navigation of a vessel;

At a speed which endangers the safety of any person, other vessel, buoy, moorings, banks of the port or any other property.

Without reducing speed and wash effect to a safe level when passing a dredger, vessel engaged in diving or underwater operations, or working on a buoy or mooring.

At a speed in excess of 6 knots north of an imaginary line between Hythe Pier and Western Shelf buoy.

Collision Avoidance Check List

Avoid ship channels. Cross them quickly and at right angles.

Be alert. Watch for ship traffic.

Be seen. Especially at night.

Know whistle signals - five or more means Keep Clear.

Listen to VHF R/T channel 12 - if you have to transmit keep your message brief, say what you have to say, then keep listening.

Use up-to-date navigation charts - read Local Notices to Mariners at your local club or marina.

When in doubt, Keep Clear. Always be prepared for the unexpected. Lifejackets do not help if you are not wearing them.


Rule 9 (b) - A vessel of less than 20 metres in length or a sailing vessel shall not impede the passage of a vessel, which can safely navigate only within a narrow channel or fairway.

Rule 9 (d) - A vessel shall not cross a narrow channel or fairway if such crossing impedes the passage of a vessel which can safely navigate only within such channel or fairway. The latter vessel may use the sound signal prescribed in Rule 34(d) if in doubt as to the intentions of the crossing vessel.


Rule 10(b) - A vessel using a Traffic Separation Scheme shall: (i) proceed in the appropriate traffic lane in the general direction of traffic flow for that lane; (iii) normally join or leave a traffic lane at the termination of the lane, but when joining or leaving from either side shall do so at a small an angle to the general direction of flow as practicable.

Rule 10(c) - A vessel shall, so far as practicable, avoid crossing traffic lanes but if obliged to do so shall cross on a heading as nearly as practicable at right angles to the general direction of traffic flow.

Rule 10(j) - A vessel of less than 20 metres in length or a sailing vessel shall not impede the safe passage of a power-driven vessel following a traffic lane.

Rule 18(b)(ii) - A sailing vessel under way shall keep out of the way of a vessel restricted in her ability to manoeuvre.

Rule 18(d)(i) - Any vessel other than a vessel not under command or a vessel restricted in her ability to manoeuvre shall, if the circumstances of the case admit, avoid impeding the safe passage of a vessel constrained by her draught, exhibiting the signals in Rule 28.


Rule 19(a) This Rule applies to vessels not in sight of one another when navigating in or near an area of restricted visibility.

Rule 19(b) Every vessel shall proceed at a safe speed adapted to the prevailing circumstances and conditions of restricted visibility. A power-driven vessel shall have her engines ready for immediate manoeuvre.

Rule 19(c) Every vessel shall have due regard to the prevailing circumstances and conditions of restricted visibility when complying with the Rules of Section I of this Part.

Rule 19(d) A vessel which detects by radar alone the presence of another vessel shall determine if a close-quarters situation is developing and/or risk of collision exists. If so, she shall take avoiding action in ample time, provided that when such action consists of an alteration of course, so far as possible the following shall be avoided:

Rule 19(d)(i) an alteration of course to port for a vessel forward of the beam, other than for a vessel being overtaken;

Rule 19(d)(ii) an alteration of course towards a vessel abeam or abaft the beam.

Rule 19(e) Except where it has been determined that a risk of collision does not exist, every vessel which hears apparently forward of her beam the fog signal of another vessel, or which cannot avoid a close-quarters situation with another vessel forward of her beam, shall reduce her speed to the minimum at which she can be kept on her course. She shall if necessary take all her way off and in any event navigate with extreme caution until danger of collision is over.

With particular reference to the conduct of vessels (including pleasure craft) in restricted visibility, the MCA have released guidance in the form of MGN 369 Navigation In Restricted Visibility which can be accessed here.


  • Check the weather forecast by listening to the shipping or local radio forecast, watching Teletext ITV, telephoning the Maritime and Coastguard Agency or listening to its reports on VHF Channel 67.

  • Check the condition of the boat and its equipment.

  • Ensure the engine is well maintained. Carry a tool kit and essential spares.

  • Ensure safety equipment is in good order and is provided for all on board.

  • Carry day and night distress flares, first aid kit and a torch.

  • Carry VHF radio with marine frequencies, do not rely on Cellnet and other portable phones.

  • Check local conditions, tide rates, shoal waters.

  • Obtain and carry the appropriate charts and tide tables.

  • Plan your trip.

  • Ascertain how long the voyage will take.

  • It is prudent to set watches for crew members.

  • Plan safe havens en route and alternatives.

  • Have sufficient crew for voyage.


Used to indicate that the vessel (or aircraft) is in grave and imminent danger, is sinking or about to sink or is on fire.

Used to indicate that the station has a very urgent message concerning the safety of a ship or person on board.

Used to indicate that the station is about to transmit an important navigational or meteorological warning.


'V': "I require assistance."
'F': "I am disabled; please communicate with me."
'Q': "I request free pratique, my vessel is healthy."
'U': "You are running into danger."
'O': "Man overboard."
'W': "I require medical assistance."


When the helicopter is sighted by a boat in distress, a flare, orange smoke signal, dye marker or a well-trained Aldis lamp will assist recognition (very important if there are other vessels in the vicinity).

Survivors from a yacht with a mast may need to be picked up from a dinghy or liferaft at least 100 ft (30 m) away.

If a crewman descends, he will take charge: obey his instructions. Never secure the winch wire to the yacht and beware that it may carry a lethal static charge if it is not dipped (earthed) in the sea before handling.


'SPOT IT!' is designed to capture an Potentially Dangerous Situation, Near Miss or Unsafe Practice that could cause an accident or injury to someone, a security issue or impact the environment or our energy consumption. The system has been extended to also capture suggestions for improvement or examples of best practice. By recognising and reporting the situation, action can be taken in time to prevent an accident or to share a positive learning across ABP. Please keep your eyes open, report anything of concern or interest, whether on land or afloat, and help us to embed a culture of not walking by. Should you have an issue you want to report, please follow the link here.