As in the fourth exploration, Captain Ishii with his CHOEIMARU took us to a point 2.4km south of 1F (Fukushima Daiichi Nuclear Power Plant). This time we attached an on-line posture censer to the detector to know whether it stayed upright or not. The posture censer worked fine. We confirmed that the detector stayed mostly upright while we collected the data. After this point we went back to south to do measurements at those points previously explored.