As it was not yet sunset when he initially approached the coast, Hess backtracked, zigzagging back and forth for 40 minutes until it grew dark. Around this time his auxiliary fuel tanks were exhausted, so he released them into the sea. Also around this time, at 22:08, the British Chain Home station at Ottercops Moss near Newcastle upon Tyne detected his presence and passed along this information to the Filter Room at Bentley Priory.