From a photographic composition point of view it would have been better had the Utility vessel Willchallenge and the unmanned dredger/underwater operations vessel CW4-100 been much closer together but as they were not connected by any towing line it was probably for operational reasons that they were spaced apart as they were. No doubt CW4-100 was radio controlled from Willchallenge. According to Internet sources CW4-100 is Registered in the United Kingdom, has a length of 4 Metres and a width of 2 Metres. I believe it can also be described as an Autonomous Surface Vehicle. When I saw the two vessels on the 25th of March 2022 they were motoring together down Southampton Water, heading in the direction of the Solent. Later on during the same day they appeared to be working off the Reach Navigation Buoy in the Solent. The image was captured from the Moat Wall of Calshot Castle.