White Star Lines contracted with the Harland & Wolff shipyard in Belfast for construction of three luxury transatlantic passenger ships. They were to be the largest such ships in the world, White Star opting for luxury and passenger numbers, rather than speed. The first ship, the RMS Olympic, entered service in 1911 and had a 24-year career. The second ship was the RMS Titanic, lost on its maiden voyage in 1912. The third ship, originally designated the RMS Britannic, was under construction when tragedy struck the Titanic. Design changes were soon made. The tops of the five forward watertight bulkheads were raised to the B-Deck level. More lifeboats and davits were added to fully accommodate all passengers and crew. A double hull was installed in way of the engine rooms and boiler rooms. The maximum hull width (beam) was increased by two feet to improve stability. Finally, a larger turbine (18,000 horsepower) was installed on the center shaft so as to retain the original design speed of 21 knots. As a result of these changes, the Britannic was not launched until February 1914, when fitting out began. With the outbreak of World War I in August, military authorities placed warships at the top of the priority list, further delaying full completion of the Britannic. In November 1915, the British Admiralty requisitioned the Britannic for service as a hospital ship. Two large red crosses were painted on each side, along with a broad horizontal green stripe. The ship was officially designated as His Majesty’s Hospital Ship Britannic. It made five uneventful trips to the Mediterranean Theater, returning wounded soldiers to Britain for medical treatment. Its sixth and final voyage departed Southampton for Lemnos, Greece on 12 November 1916. It entered the Mediterranean Sea on 15 November and stopped briefly in Naples for refueling and resupply before proceeding toward Lemnos. There were 1,066 crew and medical personnel on board. Steaming around the Attica Peninsula, the hospital ship entered the Kea Channel between the peninsula and the island of Kea on 21 November. At about 8:12 in the morning, it was struck by a major explosion on the starboard side between holds two and three. The first four watertight bulkheads were damaged, allowing extensive flooding. Bulkheads were distorted, preventing closure of a number of watertight doors. In the panic, portholes in the lower decks that had been opened for ventilation were not closed, allowing for entry of even more water as the ship listed. As the captain attempted to turn the listing ship for beaching on the island of Kea, several lifeboats that had been launched without authority were sucked into the screws. The lifeboats and their occupants were destroyed. The captain ordered the engines to be stopped and for everyone to abandon ship. The HMHS Britannic sank at 9:07 a.m. on 21 November 1916 several miles off Kea in 400 feet of water. There were 1,036 survivors, most of the 30 deaths resulting from the early and unauthorized launching of two lifeboats. The wreck was rediscovered by Jacques Cousteau in 1975, who, with scant evidence, opined that the ship had been sunk by a torpedo. Mooring anchors for mines were later found in the vicinity. The wreck is a protected war memorial.