The Royal Australian Navy's Hydrographic Ships Leeuwin and Melville are based in Cairns, North Queensland. These 71 m long ships enable the Australian Hydrographic Service to collect high-quality bathymetry data within Australia's regional seas. I was invited onboard HMAS Leeuwin to observe the new RESON SeaBat T50-R multibeam sea trial.
Sailing from Cairns on 11th October, we headed towards Green Island and the location of an old coal barge wreck lying in about 37 m depth. The wreck was an ideal spot to conduct patch testing for the dual-head T50-R multibeam.
The data quality were excellent, requiring hardly any editing of noise. The wreck's exterior was clearly seen rising vertically from the seafloor. Within the point cloud, we could also view the internal frames and debris lying on the seafloor beside the wreck.
A transit out of Grafton Passage to the Coral Sea allowed the deepest depth to be recorded with the multibeam, and we could also see the drowned reefs that rim the Great Barrier Reef shelf-edge.
Many thanks to the Commanding Officer and crew of HMAS Leeuwin for a great day and the opportunity to watch such an advanced multibeam system in operation.