King's Harbour Master Portsmouth

LNTM No 38/22

1. NOTICE IS HEREBY GIVEN by the Queen's Harbour Master Portsmouth that the Autonomous Vessel MAYFLOWER will transit the Dockyard Port of Portsmouth and berth in Portsmouth Harbour in the period 5-12 March 2022.  

2.  MAYFLOWER is an unmanned 16 metre long white-hulled trimaran capable of fully autonomous operations. The vessel will depart Plymouth on or after 4 March, making a transit along the south coast and through the Solent to Portsmouth, arriving on or after 5 March. Weather permitting, MAYFLOWER will return to Plymouth 11-12 March. 


3. Throughout the passages, MAYFLOWER will be accompanied by a support boat, TALISMAN, a Halmatic Pilot Boat, painted light blue. TALISMAN will carry control equipment and will be able to take local control when necessary, will make appropriate VHF radio calls and assist MAYFLOWER in berthing and unberthing. 


4. When outside 12 nautical miles from land, MAYFLOWER will operate in fully autonomous mode and its progress will be monitored from the remote monitoring centre in Plymouth. When closer to land, MAYFLOWER will be operated in remote control, either from the remote centre or from the control equipment in TALISMAN. For operations north of Outer Spit Buoy, the station in TALISMAN will be in control and TALISMAN will remain within 20-50 metres of the MAYFLOWER. MAYFLOWER and TALISMAN will berth in the Portsmouth Historic Dockyard pontoons to the north of HMS WARRIOR 1860. 

5. While transiting the Dockyard Port of Portsmouth, MAYFLOWER and TALISMAN will both follow the International Rules for Prevention of Collisions at Sea in addition to all local rules and regulations contained in the Dockyard Port of Portsmouth Order 2005 and in General Directions published on the QHM Website ( 

6. In addition, TALISMAN will keep a constant watch on VHF Channels 11 and 12 while in the Solent and both craft will operate AIS B transceivers.  

7. Cancel this LNTM 16 March 2022. 

Thursday 03 Mar 2022

Queen'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.