The MBES was the 50 Khz, 126 1.5° beams, 150°aperture RESON 8160, capable to acquire data at a range of 3000 m depth. The sonar data were collected and recorded in realtime on HD by direct interfacing of the sonar processor P1 to the PDS-2000 software. In addition two data sets were generated and stored on separate computer for backup on HD and CD/DVD. The PDS-2000 was able to build a 25 m DTM during the acquisition of the entire surveyed area.