King's Harbour Master Portsmouth

LNTM No 109/22

1. NOTICE IS HEREBY GIVEN by the King’s Harbour Master Portsmouth that an Autonomous Surface Vessel (ASV) Sea Trial will be conducted in the Solent Areas during the period 17-28 October 2022.

2.  ASV operations will be conducted in daylight only with a safety vessel in attendance throughout. MAST 9 is a 9-metre craft, is coloured grey and has a top speed of 50 knots. MAST 9 will be accompanied by VALKYRIE 6, which will accompany the craft from/to Trafalgar Wharf to the operating areas and will act as the safety vessel for the trials. The staff operators embarked in VALKYRIE 6 will intervene in the event of any safety issues as will the onboard coxswain. For the trial serials, MAST 9 will be remotely/autonomously controlled, but crewed throughout, with the operators able to regain control quickly should circumstances require this. Speeds used for trials will vary but will remain within the 10-knot speed limit when within 1000 yards of the mean low water springs line.



3. The trial will take place from approximately 1000 to 1500 on each day in the Solent areas, off Osbourne Bay and Hayling Bay as shown below. MAST 9 will be operated in remote/ autonomous mode only when in the trials area. For transit to and from the demonstration area MAST 9 will be operated from inboard. The trial staff crewing the safety boat will verify that the proposed trial is safe to continue

Osbourne Bay operating area (Chart not to be used for navigation)

50° 44.578’N  001° 12.567’W start/finish
1. 50° 45.326’N  001° 14.810’W
2. 50° 45.661’N  001° 14.517’W
3. 50° 44.914’N  00°1 12.262’W

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

50 °45.746’N  001° 3.023’W start/finish
1. 50° 45.814’N  000° 58.016’W
2. 50° 44.769’N  000° 57.999’W
3. 50° 44.914’N  001° 3.030’W

4. The safety vessel VALKYRIE 6 and MAST 9 will be listening on VHF Ch 11, Ch 12 and 16. Where possible, trials vessels will maintain a 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 29 October 2022.


Wednesday 12 Oct 2022

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.