When did Titanic sink and how long did it take? A timeline of the disaster

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11:00 | Due to high winds, Captain Smith decides to cancel Titanic’s first lifeboat drill. This will prove to be significant when the evacuation of the ship becomes frantic almost 13 hours later.

13:42 | Another warning comes Titanic’s way, this time from the Greek ship Athenai, relayed via RMS Baltic. It cautions the crew about "passing icebergs and large quantities of field ice" in the area. The chairman of the White Star Line, J Bruce Ismay, is on board Titanic; he always travels on the maiden voyages of his ships. Smith informs Ismay that a sharp lookout will be kept and that ice will be seen in time to avoid it, given the calm and clear weather conditions. Titanic keeps to the longer steamer track to New York, which is advised during the iceberg season.

19:20 | The radio operators pick up further reports, this time issued by SS Californian, of three large icebergs. This message is delivered to the bridge by radio operator Harold Bride, where it is posted on the notice board for officers. Captain Smith is not on watch at the time, and is dining with passengers travelling first class, leaving the ship in the command of Titanic’s Second Officer, Charles Lightoller.

21:40 | Senior radio operator Jack Phillips receives yet another warning from yet another ship, SS Mesaba, reporting of multiple large icebergs just 15 miles ahead of Titanic. However, there’s a communication breakdown. Messages for a ship’s captain should be prefixed with the letters ’MSG’, but because Mesaba’s missive hasn’t been labelled correctly, Phillips does not treat it with the utmost urgency. Instead, he carries on with the pressured task of sending a large backlog of passenger telegrams now that he is within range of the Cape Race relay station on Newfoundland.

22:00 | Two of the ship’s lookouts – Frederick Fleet and Reginald Lee – take their positions up in the crow’s nest. The task of spotting icebergs, especially the smaller growlers, is difficult for a number of reasons. It’s a moonless night, meaning that they’re peering into darkness, save for bright starlight and the ship’s own lights. It’s also an incredibly still night. Had the ocean been choppier, the pair could have spotted water breaking against the icebergs. And they’re without binoculars, which have been misplaced during a crew rearrangement. However, as binoculars do not speed the process of spotting icebergs at night this position is not corrected.

22:55 | A casual but vital warning comes from the nearby Californian – "Say, old man, we are stopped and surrounded by ice". But in Titanic’s radio room, Jack Phillips is too preoccupied with sending passenger telegrams, and the message from the nearby ship is so loud that it nearly deafens him. His response is curt to say the least: "Shut up! Shut up! I am busy. I am working Cape Race."

23:30 | With his ship stationary until at least first light, when it can safely navigate its way out of what will become known as ’Iceberg Alley’, Californian’s radio operator switches off his equipment and goes to sleep after 16 hours of work, quite possibly a little aggrieved at the rudeness of his opposite number aboard Titanic. Had he held his position for just half an hour longer to receive the distress calls of the other ship, the subsequent loss of life may have been much less.

23:39 | Titanic, now 400 nautical miles south of the Grand Banks of Newfoundland, is seconds away from disaster. But despite the multiple warnings its crew have received throughout the day, the vessel continues to crack on at just two knots slower than its top speed of 24 knots because the weather remains unusually clear. Ensuring an early arrival in New York would be a notable publicity coup for the White Star Line company and the new Titanic.

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Up in the crow’s nest, Frederick Fleet spots an iceberg right in the ship’s path. He rings the look-out bell three times and calls the bridge, where Sixth Officer James Moody receives Fleet’s urgent, unequivocal words: “Iceberg, right ahead!” Moody relays the message to First Officer William Murdoch, who in turn instructs Quartermaster Robert Hichens to instantly change the ship’s course to “hard-a-starboard” and for the engines to be put into reverse.

23:40 | Although it takes around 30 seconds for the steam-powered mechanism to turn the rudder, that’s just enough time to avoid a head-on collision between liner and iceberg. But the starboard side does make significant contact, with an underwater spur of ice scraping along the ship for seven seconds. In his cabin, Captain Smith feels the impact and quickly makes his way to the bridge where he’s informed of the collision. Many passengers continue to sleep, unaware of what’s just occurred and the devastation it will unleash.

23:45 | All of Titanic’s engines are switched off and the ship now faces north, albeit drifting southwards. The chief architect, Thomas Andrews, is also on board for this maiden voyage and is summoned to the bridge by Smith. Titanic is divided into 16 watertight compartments. Even if four of the forward compartments were to be flooded, the ship should still remain afloat. But when Andrews surveys the damage over the next few minutes, he finds that five compartments have been ripped open by the collision. His diagnosis to Smith is a grim one: Andrews predicts that Titanic will be completely underwater within a couple of hours, if not sooner.

15 April 1912

00:05 | Smith orders the lifeboats to be readied in order for as many people to be evacuated as possible. Stewards move speedily though the ship, banging on cabin doors to rouse the occupants, whether crew or fare-paying passengers, since Titanic has not been fitted with a public-address system. The evacuation is an unequal one. The ratio of stewards to passengers in the first-class accommodation means the latter have great assistance from the staff, helping them to dress and escorting them up onto deck. In the more populous third-class accommodation, passengers are largely left to manage their own passage from cabin to deck, with directions from stewards. In the first-class lounge, the band play to entertain those waiting for the lifeboats.

00:20 | With passengers instructed to put on lifebelts, the loading of the lifeboats gets underway. Titanic has 20 lifeboats in all, with a combined capacity of 1,178 – little more than half the number of people on board. The ship had been designed to carry 64 lifeboats, but the White Star Line company had complied with the current regulations and only fitted fewer than a third of them. Lifeboats on a properly subdivided ship like Titanic in 1912 were intended to ferry passengers from the stricken vessel to a nearby rescue ship, and uninterrupted views of the ocean from the main deck were deemed to be more pleasing to the eye of its passengers, rather than rows of lifeboats. With this insufficient number of lifeboats, Captain Smith explains the priority to First Officer William Murdoch and Second Officer Charles Lightoller: "put the women and children in and lower away".

By now, several vessels have received the distress signals sent by radio operators Phillips and Bride. Many are too distant to offer assistance, but Carpathia – another liner belonging to the rival Cunard company – is comparatively close at 58 nautical miles away. "Come at once. We have struck a berg." Carpathia immediately changes course, but it will still take at least three hours to arrive. Exactly what its crew will encounter when they eventually arrive remains unclear.

00:25 | The grim mathematics are inescapable. By now, 45 minutes after the collision, 13,700 tonnes of icy water have poured into a ship that’s only capable of pumping out 1,700 tonnes per hour. Titanic’s fate is sealed as the much nearer Californian, with its radio operator asleep, does not understand the ship’s plight and fails to come to its aid.

00:45 | The first Titanic lifeboat, No 7, is lowered onto the ocean and starts rowing away from the stricken ship. There are believed to be just 27 people aboard it, 38 fewer than its capacity. A significant number of first-class passengers refuse to board the lifeboats. Among them is the industrialist millionaire Benjamin Guggenheim who, along with his valet, removes his life-vest and changes into evening wear, including a top hat. "We have dressed up in our best and are prepared to go down like gentlemen", he is reported to have said.

Others don’t have an option. Very few third-class passengers will make it onto the deck, let alone find a seat in a lifeboat. Indeed, many third-class passengers travelling as families choose to stick together and trust the ship, rather than have the women and girls risk their lives on the ocean at night in a small lifeboat, and abandon the male members of their family – including boys of 13, who are regarded as adults in 1912.

00:55 | Lifeboat No 7 is far from the only underpopulated craft; No 6 is thought to have only 23 people on board. More lifeboats are lowered every few minutes, rarely at capacity. Lifeboat No 1 carries just a dozen passengers. Early lifeboats are sent unfilled due to the initial reluctance of passengers nearby to enter them, and because the crew’s main objective is to get all the boats launched before Titanic sinks with its lifeboats still attached to the ship.

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01:30 | After the first hour following the collision, the downward angle of the ship had remained relatively steady at around five degrees, offering a modicum of reassurance to both passengers and crew that they might be rescued in time. However, by 01:30, that angle has increased to 10 degrees as Titanic continues to take on water at an alarming rate. A group of male passengers tries to rush Lifeboat No 14 as it’s being lowered with 40 people already on board. Three shots fired in the air by Fifth Officer Harold Lowe manages to halt the melee.

01:35 | At the wireless operators station, an ominous message is sent over the ship’s radio and picked up by Carpathia: "Engine room getting flooded." Ten minutes later, the update is even more alarming: "Engine room full up to boilers." It will be the final intelligible message sent over Titanic’s radio system.

02:05 | The last of the 20 lifeboats – collapsible D – is lowered from the ship. The last few lifeboats have been closer to capacity now that the fate of the “unsinkable” ship is clear to all left on board.

02:15 | Titanic’s downward angle gets much steeper as water pours in through open port holes and deck hatches into areas of the ship previously unflooded. A wave caused by the rapid sinking of Titanic causes people to be swept into the ocean. The front funnel collapses and several passengers are crushed to death.

02:18 | The ship’s lights go out and the frantic scene is now plunged into darkness. Under the weight of the stern, which is now lifted out of the water by the sinking bow, Titanic begins to split into two.

02:20 | The world’s most modern ocean-going liner completely disappears under the surface of the Atlantic. "There is no danger that Titanic will sink," White Star Line vice-president Phillip Franklin reassures the waiting press, after news of the collision first reaches New York. But those who have survived being thrown into the water will perish, many from cardiac arrest, within half an hour. Second Officer Lightoller, the most senior crew member to survive the disaster after managing to cling onto an upturned lifeboat, will later describe the sensation of plunging into the freezing waters as being akin to "a thousand knives" penetrating his body.

02:26 | The bow and the stern, now separated, reach the seabed, having rapidly corkscrewed to a depth of nearly 4,000 metres in just six minutes.

03:30 | Rockets fired by Carpathia are spotted by those aboard the lifeboats. Having dodged innumerable icebergs, its crew have travelled at high speed, with the heating system turned off so as much steam as possible could be available for its engines.

04:00 | The rescue begins; survivors are brought on board Carpathia by rope ladder and slings. Children are hauled aboard in mail sacks.

08:30 | Californian arrives at the scene of the disaster but, after a two-hour search, they find there are no remaining survivors to rescue. The ship’s radio operator had only learned of the disaster when he logged back on early this morning.

08:50 | The last of the survivors are now aboard Carpathia. The decision is made to take them to New York City, Titanic’s intended destination. J Bruce Ismay is among those rescued, having found himself a berth on a lifeboat (and for which he will later be renounced as a coward). Ismay has already sent a grim message to the White Star Line offices in Manhattan, which was relayed to the waiting press. "Deeply regret advise you Titanic sank this morning fifteenth after collision iceberg, resulting serious loss of life, further particulars later."

18 April 1912

21:30 | After a difficult voyage through ice, fog and thunderstorms, Carpathia arrives in New York. It initially visits Pier 59, where the empty lifeboats are unloaded to go back into White Star Line’s care, before sailing on to Pier 54, where an estimated 40,000 people are waiting in heavy rain. Only 705 Titanic passengers and crew have made it to New York. More than 1,500 lives have been lost at sea.

Nige Tassell is a freelance journalist specialising in history

This article first appeared in the July 2021 issue of BBC History Revealed