He returned to his cabin, and at 11:40pm, was just nodding off when he felt a grinding vibration. Still in his pyjamas, he went on deck where he met Third Officer Herbert Pitman who had also been disturbed by the vibration. They concluded that the vessel had hit something, but could see no sign of anything. There was no sign of undue alarm on the bridge so they returned to their cabins to await orders.
Ten minutes later, Fourth Officer Boxhall entered his cabin and informed him that "the water was up to the F deck in the Mail Room." Lightoller pulled a pair of trousers, pullover and a bridge coat over his pyjamas and went out on deck.