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KHM Portsmouth



King’s Harbour Master Portsmouth

LNTM 04/24

1. NOTICE IS HEREBY GIVEN by the King’s Harbour Master Portsmouth, for the benefit of owners and operators of recreational vessels, Rigid Inflatable Boats (RIBs) and other fast craft, to draw attention to the risk to both themselves and others as well as to the basic safety measures required to assist in keeping marine risks as low as practicable.

2. The Marine Accident Investigation Branch (MAIB) have published a report into the tragic deaths of a father and daughter thrown from a RIB travelling at high speed. Neither were wearing a lifejacket, the hydraulic steering of the RIB was in poor condition and they were conducting no basic safety precautions. The full MAIB report on this accident is available at:

3. IMPORTANCE OF USING A KILL CORD The kill cord serves one purpose, to stop the engine when the driver moves away from the controls. It is essential that all owners and operators of vessels fitted with kill cords:
• Test kill cords regularly to ensure that the engine stops when the kill cord mechanism is operated.
• Make sure that the cord is in good condition.
• Always attach the cord securely to the driver, ideally before the engine is started, but certainly before the boat is put in gear.
• Stop the engine before transferring the kill cord to another driver.
The RYA guidelines surrounding the use of killcords are available at:

4. WEARING OF SUITABLE LIFEJACKETS/CARRYING OF LIFESAVING EQUIPMENT (INCLUDING FLARES) While not a legal requirement for certain types of small private recreational craft; the habit of routinely wearing a suitably tested personal floatation device for your activity, cannot be emphasised sufficiently as a minimum precaution to such exposed personnel (especially children). This characteristic alone can dramatically increase both survival and rescue probability. The Volunteer Harbour Patrol (VHP) in Portsmouth will additionally remind such mariners of the importance of wearing the right lifejacket/floatation device whenever possible.

The RYA Information on this subject can be found here:

The RYA also publish a guide to safety equipment and that should be carried onboard pleasure vessels which can be found here:

5. SAFE SPEED The maintenance of a safe speed at all times, within the specified speed limit, has a direct bearing on reducing the to risk to both life and property.  Not only is this relevant to the occupants of the “speeding” vessel but also to those who encounter the associated wake and risk of collision.  GD 5/23 (Speed Limits) is and will continue to be strictly enforced by KHM.  Of particular note, the 10 knot speed limit applies within half a mile of the shore, throughout the Dockyard Port of Portsmouth which covers the majority of the eastern Solent. Mariners should also be mindful of the wash their vessel is creating, particularly when transitting in close proximity to boats moored in the vicinity. Further guidance surrounding wash can be found in GD 19/23 (Wash Effects).

6. VHF GUARD   Within the Solent and especially within the Dockyard Port of Portsmouth (due to the traffic density) the continual monitoring and significance of carrying a portable VHF set (or better) and a good VHF guard by all mariners is vital for traffic coordination. This is detailed at LNTM 02/24. The essential use of VHF for all craft to safely transit and cross the harbour (see GD 2/23 – Portsmouth Harbour Entrance – Approach Channel, Small Boat Channel, Swashway and inner Swashway) reaffirms this and reminds the recreational user that help is only a call away. Users of the Small Boat Channel are recommended to maintain a listening watch on VHF Ch11 during their transit. Search and Rescue operations are primarily a Coastguard responsibility, but again, a careful guard of VHF is important here, both to obtain assistance if required and to assist other mariners if needed.

7. DON’T DRINK AND GO BOATING The Royal Yachting Association (RYA) and the British Ports Association (BPA) fully support the Government in raising alcohol awareness and highlighting the dangers of drinking and boating. Although many recreational users enjoy boating responsibly, unfortunately, the issue of drinking in the marine environment has contributed to incidents around the UK coast, including in the Solent. The message is clear - don’t mix alcohol and boating. The RYA encourages all boaters to behave responsibly and to understand how alcohol can affect their safety and the safety of others. Put simply, alcohol distorts your perception of risk and your own abilities; it affects your balance, impairs your judgement, and slows your reactions.

8. GOOD LOOKOUT  Simple but vital to all mariners,  this measure can save lives if followed diligently.  In particular, vessels operating at speed in the Solent should be particularly vigilant towards the presence of other small craft as well as swimmers and divers marked by floats and support craft flying flag Alpha.

9. NARROW CHANNELS  The Portsmouth approach channel, entrance and the harbour are frequently used by deep draught warships, ferries and commercial traffic that can safely navigate only within the channel.  Small craft operators are advised that they are to adhere to the requirements of LNTM 08/24 (Vessels Constrained by their Draught) and to Rule 9 (Narrow Channels) of the International Regulations for the Prevention of Collisions at Sea (COLREGS) in that they are not to impede the passage of vessels which can safely navigate only within a narrow channel.

10. TIDAL STREAM IN PORTSMOUTH HARBOUR ENTRANCE The tidal streams in the harbour entrance can run up to 5 knots, particularly during spring tides. Users of the Small Boat Channel (GD 2/23 Portsmouth Harbour Entrance - Approach Channel, Small Boat Channel, Swashway and Inner Swashway) should be mindful of their chosen times to exit and enter the harbour as strong cross currents and back eddies can be encountered; this is especially applicable to the Harbour Entrance where cross currents can sweep boats into the main channel. Mariners are advised to consult Admiralty Charts 2625 and 2629, and Tidal Stream Atlas NP 219 for further details.

11. SPECIAL OPERATIONS  Portsmouth Harbour and approaches are frequently used for Ministry of Defence Police (MDP) and military training and operations when MDP launches special forces small attack training craft are permitted to exceed the speed limit and other safety requirements under dedicated risk assessment criteria (see LNTM 06/24 – Fast transits by military craft). Furthermore specific risk assessments for recreational events are also required (see LNTM 03/24) to ensure all the hazards have been reduced to an acceptable level. This is controlled by KHM and all mariners need to remain alert to their existence, activity and relevance.

12. BOAT LICENSING REGULATIONS  For the small pleasure boat user who hires out or has paying guests there is a legal requirement to achieve successful inspection and certification on an annual basis. Details of this are to be found at

13. REPORTING DAMAGE OR INCIDENTS  All damage to craft and navigational incidents in the Dockyard Port of Portsmouth need to be reported to KHM.  See GD 03/23 on directions to be followed.   

14. WEBSITE ADVICE/INFORMATION  The following sites are all relevant to enhancing recreational safety on the water and worthy of revisiting and updating before returning afloat this year. for KHM Local Notices to Mariners, Navigation Warnings and General Directions for Portsmouth International Port information for general information and advice  for Southampton local information for MAIB Reports / Actions for recreational safety and information

15. Finally, all mariners are reminded of the importance of a good appreciation of likely weather to be encountered (including fog) on their planned passage especially taking into account the heavy density of all types of traffic in the Solent throughout the year. Ensuring such basic precautions are followed will improve safety and enjoyment for all local users.

16.       Portsmouth LNTM 04/23 is hereby superseded.


Monday 01 Jan 2024

King's Harbour Master

Owners, Agents, Charterers, Marinas, Yacht Clubs and Recreational Sailing Organisations should ensure that the contents of this Notice are made known to the masters or persons in charge of their vessels or craft.

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