The latest Autosub Long Range (ALR) vehicle being developed by the National Oceanography Centre (NOC) (www.noc.ac.uk) in Southampton has completed its first trials in the waters of Portland Harbour in Dorset.

This autonomous vehicle — named ALR150 for the 1,500m depth it can reach — passed its first major test in late March with flying colours, successfully demonstrating its integration with the unified command and control software platform developed by the NOC in partnership with the Scottish Association for Marine Science (under the Oceanids programme).

The trials have shown that the vehicle’s hardware and software systems are communicating effectively with each other, which provides a solid platform for ever more advanced features to be added.

The ALR1500 is one of three vehicles designed to enhance the marine observing capabilities available to the UK’s science community.

It is designed to have greater endurance and payload capacity than the current 6,000m-rated models, which need heavy pressure vessels to operate at such extreme depths.

Optimised for surveying the continental shelf and upper slope, the ALR1500 will have the potential for missions covering hundreds or thousands of km over periods of several weeks or months.

This opens up new possibilities, such as a full trans-Arctic under-ice mission.

The harbour acceptance trial was not just of interest to engineers and scientists.

A bottlenose dolphin paid a visit and appeared curious about this new addition to the underwater environment.

Further trials scheduled to take place in Loch Ness in the coming months will test the vehicle’s Terrain Aided Navigation, environmental profiling capabilities and other functions.