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KHM Portsmouth



King’s Harbour Master Portsmouth

LNTM 35/24

1. NOTICE IS HEREBY GIVEN by the King’s Harbour Master Portsmouth that Autonomous Uncrewed Underwater Vessel (AUUV) trials will be conducted In the Solent areas of either Stokes Bay or Ryde Middle from 26 February to 1 March 2024. 

2. AUV operations will be conducted in daylight hours only with a safety vessel in attendance. The AUUV “IVER4-900” is a black and grey 2.5 m long craft which will be supported by EAGLE (LOA 15m) acting as safety and control boat. “IVER4-900” will be both launched and recovered in the operations area and remotely controlled, from the vessel EAGLE with the remote operator following the International Rules for Preventing Collisions at Sea (COLREGS) at all times.

The IVER 4-900 is 2.5m long AUUV weighing 110kg, it is the first in a family of advanced UUVs to address a wide variety of missions. The vehicle comes standard with industry leading tracking and safety communications, precise measurements, repeatable high accuracy navigation, and low drag side scan and bathymetry transducers. Its top speed is 3 knots.

Support Boat EAGLE

The workboat is owned and operated by Constructex and has a maximum capacity of 12 persons including skipper and crew. The boat is equipped with a davit which will be used to lift the AUUV. During transit the AUUV will be secured to the deck using strops. EAGLE is coded MCA CAT 2.

3. The trials will be around Browndown point to Gilkicker Point (Stokes Bay), Ryde Middle and the most northern section of Portchester Lake; to the North of Trafalgar Wharf dry stack 

NOTE : Portchester Lake is to be used as a ‘back up’ location in inclement Weather; and for pre-trial vessel checks. The IVER4-900 will be operated on the surface only in this area.

Browndown Point to Gilkicker Point

The Latitude and Longitude for the Stokes Bay Trial Operating Box are as follows:
50º 46.989 N  001º 10.785 W
50º 46.989 N  001º 08.651 W
50º 46.152 N  001º 08.651 W
50º 46.152 N 001º 10.785 W

Ryde Middle

The Latitude and Longitude for the Ryde Middle Operating Box are as follows:
50º 45.826 N  001º 15.504 W
50º 46.879 N  001º 15.504 W
50º 46.879 N  001º 11.790 W
50º 45.826 N 001º 11.790 W

Portchester Lake 

The Latitude and Longitude for the Portchester Lake Operating Box are as follows:
50º 50.683 N  001º 06.745 W
50º 50.733 N 001º 06.745 W
50º 50.733 N 001º 06.533 W
50º 50.683 N 001º 06.533 W

4. Trials will involve a variety of manoeuvres and equipment tests. IVER 4-900 will remain under control from EAGLE at all times, and the pilot will maintain at least 200 metres separation from other shipping.

5. The safety vessel will be listening on VHF Ch 11 and Ch 12 and will contact KHM at the beginning and end of serials. 

6. Cancel this LNTM on 2 March 2024.


Thursday 22 Feb 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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