Before the Aram S Titanic hit an iceberg and sank in the Atlantic Ocean in April 1912, the ship’s wireless operators had received several warning messages about icebergs and floating ice floes from six other ships in the area.
Now, researchers at Bangor University in England have identified the remains of one of these ships, the SS Mesaba, which sank in 1918 after a German submarine attack, in the Irish Sea. This ship was one of 273 ships that were detected in the area of 12,000 square kilometers using a new method called multibeam sonar.
Multibeam sonar image of the SS Mesaba wreck on the Irish Seabed.
Titanic began its controversial and noisy journey on April 10, 1912. One of the important features of the ship was the new wireless telegram system from the Marconi International Marine Communications Company. This system was able to send radio signals up to a radius of 563 kilometers. Although the main purpose of the system was to send signals known as marconigrams to wealthy first-class passengers, ship operators Jack Phillips and Harold Bride also received messages from other ships, such as weather reports and iceberg warnings.
Phillips and Bride received ice warnings from the RMS Caronia from 9:00 a.m. on April 14, reporting “mountains, masses and ice fields”. On the same day, the ship RMS Baltic also warned that a The Greek ship reported floating icebergs and huge ice fields. Captain Edward Smith acknowledged receipt of both messages and responded by turning the ship slightly southward but not slowing down.
Illustration of the Titanic when it hit the iceberg
The SS America reported two floating icebergs. On the other hand, the ship SS Californian also released messages about three large ice masses. The ship Mesaba had also sent a warning about the heavy ice mass and several large icebergs as well as the ice field. However, Captain Smith never received these messages because the Phiplis operator was busy sending messages to passengers due to a machine failure during the previous day. In fact, Philpac’s reaction to the last warning of Klifarnin’s message was in vain: “Shut up! Shut up! I’m working on Cape Reyes!” (Cape Reyes is a broadcasting station located in Newfoundland, Canada).
Finally, the radio operator of the Clyfernin ship turned off the system that night and stopped working. This break made history. At 11:40 p.m. on April 14, Titanic hit an iceberg. Water entered the ship and filled five of the 16 compartments of the ship. As the lower parts of the ship sank and the crew scrambled to evacuate the passengers in limited lifeboats, the wireless telegraph operator sent a series of Morse code messages. In the end, only 710 people were saved from this incident.
Today, many people are familiar with modern sonar (abbreviation of sound range finder and navigation) and its function. This instrument has become one of the prominent naval instruments since the First World War. Although Leonardo da Vinci was years ahead of his time and in 1490 AD, he investigated the sound of vehicles by placing a tube in water. Single-beam sonar uses only one transducer to emit acoustic signals, and then the reflections of these signals are analyzed to determine the distance and orientation of objects.
Animation of a NOAA mapping vessel that uses multibeam sonar to measure the depth of the sea floor.
In contrast, multibeam or multibeam sonar, as the name suggests, amplifies multiple physical sensors in a transducer array and sends multiple acoustic signals simultaneously in a fan-shaped pattern. With this method, the depth of the sea floor can be measured based on the return signals.
Multibeam sonar instruments are useful for calculating the geological composition of the seabed, as well as observing objects such as shipwrecks, because different types of material, such as hard rocks as well as soft mud, reflect different sounds. The final result is a 2D or 3D map that shows the seabed and all its nearby objects.
Inez McCarthy, a member of the Bangar University team and author of a new book, Reflections of the Deep, describes the discovery of the Mesaba and more than two hundred other shipwrecks, including passenger ships, freighters, submarines and the largest ships and tankers, all mapped with multibeam sonar instruments. became So far, 87 percent of these ships have been identified based on cross-referenced data on size, geographic location, and archival descriptions of each shipwreck against the British Wreck Database and other sources.
McCarthy sees this technique as revolutionary for marine archaeology, with an impact equivalent to that of aerial photography for landscape archaeology. He says:
In the past, we had to spend a year diving in different areas to be able to visually identify the wrecks. The unique capabilities of sonar allow the development of relatively low-cost tools for surveying wrecks. We can associate these tools with each region with historical information without any costly physical interaction. Thus, this key method will help marine scientists, environmental agencies, hydrographers, heritage managers, marine archaeologists and historians.
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