"Titanic" received six warnings of sea ice on 14 April but was travelling about 22 knots when her lookouts sighted the iceberg. Unable to turn quickly enough, the ship suffered a glancing blow that buckled her starboard side and opened six of her sixteen compartments to the sea (the forepeak, all three holds, and boiler rooms 5 and 6). "Titanic" had been designed to stay afloat with four of her forward compartments flooded but no more, and the crew soon realised that the ship would sink. They used distress flares and radio (wireless) messages to attract help as the passengers were put into lifeboats.