ZCZC SA18 NAVTEX-HAMBURG (NCC) 260015 UTC APR 26 NAV. WARN. NO. 240 GERMAN BIGHT NORTH OF OWP 'GLOBAL TECH 1'. SURVEY OPERATIONS IN PROGRESS BY MV 'GEO OCEAN 8' CS 'LXAJ2' IN AREA AROUND POSITION 54-370N 006-070E. VESSEL TOWING MEASURING INSTRUMENTS. RESTRICTED MANOEVRABILITY DURING OPERATIONS. BERTH OF 0.5 NAUTICAL MILE REQUESTED. NNNN