📡 Multibeam Echo Sounder: Swath Width, Ray Refraction and Depth Error (2D cross-track section)

Cross-section of a multibeam echo sounder survey. Set depth, seafloor slope, fan angle, beam count and the sound-speed profile with its thermocline, and watch the beams bend, the swath width change and the position error appear when refraction is ignored. Same sound-speed model and ray rule as the 3D lab, with four in-page numerical checks.