King's Harbour Master Portsmouth

LNTM No 92/23

1. NOTICE IS HEREBY GIVEN by the King’s Harbour Master Portsmouth that Autonomous Surface Vessel trials will be conducted in the Hayling Bay area during the period 15 August – 1 September 2023.

2.  Autonomous Surface Vessel (ASV) operations will be conducted in daylight only with a safety vessel in attendance throughout. An ASV “P38 Aggressor” will be undertaking Sea Trials in the Hayling Bay area. P38 Aggressor is a 13 metre craft, is coloured black and has a top speed of 25 knots. P38 Aggressor will be accompanied by Valkyrie 8 for autonomous trials and SB850 or P24 for Uncrewed Trials which will act as safety vessels for the Sea Trial.  The trial staff operators embarked on the safety boat will intervene in the event of any safety issues. For the trials serials, P38 Aggressor will be remotely/autonomously controlled, with the operator following the International Rules for Preventing Collisions at Sea (COLREGS) at all times.

P38 Aggressor

Valkyrie 8



3. Trials will take place from approximately 1000 to 1600 during the day in Hayling Bay as shown below. P38 Aggressor will only be operated in remote/autonomous mode when in the area. The trial staff manning the safety boat have verified that the proposed Sea Trial is safe to continue.

The Trials area will be the Hayling Bay area shown below within the pink boxed area. 

Hayling Bay area: 

50 °45.746’N  001° 3.023’W start/finish
50° 45.814’N  000° 58.016’W
50° 44.769’N  000° 57.999’W
50° 44.914’N  001° 3.030’W

Hayling Bay trials area (Chart not to be used for navigation)

4. The assigned safety vessels will be listening on VHF Ch 11, 72 and 16. Where possible, trials vessels will maintain a minimum 200-metre separation from other craft, and trial runs will be modified or aborted if a close-quarters situation is developing. 

5. All trials vessels will obey the International Rules for Preventing Collisions at Sea (COLREGS) at all times. 

6. Cancel this LNTM on 2 September 2023.


Friday 11 Aug 2023

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.