ZCZC SA04 NCC-HAMBURG 180900 UTC APR 26 NAV. WARN. NO. 223 GERMAN BIGHT SOUTH OF OWP 'GLOBAL TECH 1'. SURVEY OPERATIONS IN PROGRESS BY MV 'GEO OCEAN 8', CS 'LXAJ2' IN AREA AROUND POSSTION 54-39,0N 006-33,0E. VESSEL TOWING MEASURING INSTRUMENTS. RESTRICTED _ANOEVRABILITY DURING OPERATIONS. BERTH OF 0.5 NAUTICAL MILE REQUESTED. NNNN