1994 maritime disaster on Baltic Sea
 sank on Wednesday, 28 September 1994, between about 00:50 and 01:50 (UTC+2) as the ship was crossing the Baltic Sea, en route from Tallinn, Estonia, to Stockholm, Sweden. The sinking was one of the worst maritime disasters of the 20th century. It is one of the deadliest peacetime sinkings of a European ship, after the "Titanic" in 1912 and the "Empress of Ireland" in 1914, and the deadliest peacetime shipwreck to have occurred in European waters, with 852 (out of 989) lives lost.
Sinking.
"Estonia" departed slightly behind schedule at 19:15 on 27 September and was expected in Stockholm the next morning at about 09:00. She was afterwards stated as carrying 989 people: 803 passengers and 186 crew.
Most of the passengers were Swedish, although some were of Estonian origin, while most of the crew members were Estonian. The ship was fully loaded, and was listing slightly to starboard because of poor cargo distribution.
According to the final disaster report, the weather was rough, with a wind of , force 7–10 on the Beaufort scale and a significant wave height of compared with the highest measured significant wave height in the Baltic Sea of . Esa Mäkelä, the captain of "Silja Europa" who was appointed on-scene commander for the subsequent rescue effort, described the weather as "normally bad", or like a typical autumn storm in the Baltic Sea. According to modelled satellite data, gusts were in the excess of at 01:00 that night over the Baltic Sea, although the ship had not yet reached the areas with the heaviest gusts before its sinking. There was some rain and temperatures around . All scheduled passenger ferries were at sea, something not unusual for this weather in the Baltic Sea. The official report says that while the exact speed at the time of the accident is not known, "Estonia" had very regular voyage times, averaging . The chief mate of the Viking Line cruiseferry "Mariella" tracked "Estonia"'s speed by radar at approximately before the first signs of distress, while the "Silja Europa"'s officers estimated her speed at at midnight.
The first sign of trouble aboard "Estonia" was when a metallic bang was heard, presumably caused by a heavy wave hitting the bow doors around 01:00, when the ship was on the outskirts of the Turku archipelago, but an inspection—limited to checking the indicator lights for the ramp and visor—showed no problems. Over the next 10 minutes, similar noises were reported by passengers and other crew. At about 01:15, the visor is believed to have separated and torn open the loading ramp behind it. The ship immediately took on a heavy starboard list (initially around 15 degrees, but by 01:30, the ship had rolled 60 degrees and by 01:50 the list was 90 degrees) as water flooded into the vehicle deck. "Estonia" was turned to port and slowed before her four engines cut out completely.
At about 01:20, a quiet female voice called "Häire, häire, laeval on häire", Estonian for "Alarm, alarm, there is alarm on the ship", over the public address system, which was followed immediately by an internal alarm for the crew, then one minute later by the general emergency signal. The vessel's rapid list and the flooding prevented many people in the cabins from ascending to the boat deck, as water not only flooded the vessel via the car deck, but also through windows in cabins as well as the massive windows along deck 6. The windows gave way to the powerful waves as the ship listed and the sea reached the upper decks. Survivors reported that water flowed down from ceiling panels, stairwells and along corridors from decks that were not yet underwater. This contributed to the rapid sinking. A mayday was communicated by the ship's crew at 01:22, but did not follow international formats. "Estonia" directed a call to "Silja Europa" and only after making contact with her did the radio operator utter the word "Mayday". The radio operator on "Silja Europa", chief mate Teijo Seppelin, replied in English: "Estonia, are you calling mayday?" After that, the voice of third mate Andres Tammes took over on "Estonia" and the conversation shifted to Finnish.
Tammes was able to provide some details about their situation but, due to a loss of power, he could not give their position, which delayed rescue operations somewhat. Tammes would later die in the sinking. Some minutes later, power returned (or somebody on the bridge managed to lower him or herself to the starboard side of the bridge to check the marine GPS, which will display the ship's position even in blackout conditions), and the "Estonia" was able to radio its position to "Silja Europa" and "Mariella". After that, Estonia sent their last radio message saying: "Todella paha, todella pahalta näyttää nyt tässä kyllä" (in English: "Really bad, it's looking really bad right now."). The ship disappeared from the radar screens of other ships at around 01:50, and sank at in international waters, about on bearing 157° from Utö island, Finland, to a depth of of water. According to survivor accounts, the ship sank stern first after taking a list of 90 degrees.
Rescue effort.
Search and rescue followed arrangements set up under the 1979 International Convention on Maritime Search and Rescue (the SAR Convention), and the nearest Maritime Rescue Co-ordination Centre MRCC Turku coordinated the effort in accordance with Finland's plans. The Baltic is one of the world's busiest shipping areas, with 2,000 vessels at sea at any time, and these plans assumed the ship's own boats and nearby ferries would provide immediate help and that helicopters could be airborne after an hour. This scheme had worked for the relatively small number of accidents involving sinkings, particularly as most ships have few people on board.
"Mariella", the first of five ferries to reach the scene of the accident, arrived at 02:12. MRCC Turku failed to acknowledge the Mayday immediately and "Mariella"'s report was relayed by Helsinki Radio as the less urgent pan-pan message. A full-scale emergency was only declared at 02:30. "Mariella" winched open liferafts into the sea onto which 13 people on "Estonia"'s rafts successfully transferred, and reported the location of other rafts to Swedish and Finnish rescue helicopters, the first of which arrived at 03:05. The former took survivors to shore, while the latter—Finnish border guard helicopters Super Puma "OH-HVG" and Agusta Bell 412 "OH-HVD"—chose the riskier option of landing on the ferries. The pilot of "OH-HVG" stated that landing on the ferries was the most difficult part of the whole rescue operation; despite that, this single helicopter rescued 44 people, more than all the ferries. MS "Isabella" saved 16 survivors with its rescue slide.
Victims.
Of the 989 on board, 138 were rescued, one of whom died later in hospital. Ships rescued 34 and helicopters 104; the ferries played a much smaller part than the planners had intended because it was too dangerous to launch their man-overboard (MOB) boats or lifeboats. The accident claimed 852 lives. Most died by drowning and hypothermia, as the water temperature was .
One of the victims of the sinking was the Estonian singer Urmas Alender. In total, 94 bodies were recovered: 93 within 33 days of the accident, and the last victim was found 18 months later. By the time the rescue helicopters arrived, around a third of those who escaped from the "Estonia" had died of hypothermia, while fewer than half of those who had managed to leave the ship were eventually rescued. The survivors of the shipwreck were mostly young males with strong constitutions, from all those who survived 111 were men but only 26 were women. Seven over 55 years of age survived and there were no survivors under age 12. About 650 people were still inside the ship when it sank. The commission estimated that up to 310 passengers reached the outer decks, 160 of whom boarded the life-rafts or lifeboats.
Official investigation and report.
The wreck was examined and videotaped by remotely operated underwater vehicles and by divers from a Norwegian company, Rockwater A/S, contracted for the investigation work. The official report indicated that the locks on the bow door had failed from the strain of the waves and the door had separated from the rest of the vessel, pulling the ramp behind it ajar. The bow visor and ramp had been torn off at points that would not trigger an "open" or "unlatched" warning on the bridge, as is the case in normal operation or failure of the latches. The bridge was also situated too far back on the ferry for the visor to be seen from there. While there was video monitoring of the inner ramp, the monitor on the bridge was not visible from the conning station. The bow visor was under-designed, as the ship's manufacturing and approval processes did not consider the visor and its attachments as critical items regarding ship safety. The first metallic bang was believed to have been the sound of the visor's lower locking mechanism failing, and that the subsequent noises would have been from the visor 'flapping' against the hull as the other locks failed, before tearing free and exposing the bow ramp. The subsequent failure of the bow ramp allowed water into the vehicle deck, which was identified as the main cause of the capsizing and sinking: RORO ferries with their wide vehicle decks are particularly vulnerable to capsizing if the vehicle deck is even slightly flooded because of free surface effect: the fluid's swirling motion across such a large area hampers the boat's ability to right itself after rolling with a wave. The same effect had caused the capsizing of seven years earlier.
The report was critical of the crew's actions, particularly for failing to reduce speed before investigating the noises emanating from the bow, and for being unaware that the list was being caused by water entering the vehicle deck. There were also general criticisms of the delays in sounding the alarm, the passivity of the crew, and the lack of guidance from the bridge.
Recommendations for modifications to be applied to similar ships included separation of the condition sensors from the latch and hinge mechanisms.
Changes stemming from the disaster.
In 1999, special training requirements in crowd and crisis management and human behaviour were extended to crew on all passenger ships, and amendments were made to watch-keeping standards. "Estonia"'s distress beacons or EPIRBs required manual activation, which did not happen. Had they been activated automatically, it would have been immediately obvious that the ship was in distress and the location would have been clear. All EPIRBs were subsequently required to deploy automatically and the accident was "instrumental in the move to legislate Voyage Data Recorders". New International Maritime Organization (IMO) Safety of Life at Sea (SOLAS) liferaft regulations for rescue from listing ships in rough water were introduced.
New designs, the "citadel concept" once again influenced by "Estonia", aim to ensure damaged ships have sufficient buoyancy to remain afloat, though cost will determine if any are built. SOLAS 90, which came into effect in 2010, specifies existing passenger ships' stability requirements and those in North West Europe must also be able to survive of water on the car deck.
2020 investigation.
On 28 September 2020, a Swedish documentary was released which used underwater equipment to film the wreck. This investigation found a 4-metre hole in the ship's hull. This prompted the Estonian prime minister and foreign minister to meet with their Swedish and Finnish equivalents and announce that a "new technical investigation" would take place.
The head of the Estonian investigation, Margus Kurm, stated publicly that he believes this new information points to a collision with a submarine and that the hole could not have happened post-sinking. In October 2020, the Estonian government published a report stating that the hole was too small to have sunk the ship as quickly as it did. The Swedish documentary makers were prosecuted for violating the sanctity of the wreck, but were acquitted on 8 February 2021 as the diving happened on a German ship in international waters. Germany had not signed the treaty that declares sanctity over the site. However, as a result of a retrial in September 2022, the filmmakers were finally found guilty and fined.
By June 2021, laws allowing the examination of the wreck for investigation of the disaster were passed in the Swedish