We have all heard at least once in our lives such concepts as the SOS signal and Morse code. For the first time, this radio signal began to be used in shipping and was firmly established in the maritime industry, like in no other.
However, do not think that such a distress message is used only at sea. It is absolutely universal, and everyone will benefit from learning how to send an SOS signal in Morse code.
Morse code: SOS
Morse code appeared almost 100 years before the invention of radio broadcasting, back in 1835, and began to be actively used by sailors to prevent and rescue from emergency situations (Figure 1).
Figure 1. Sailors were the first to use the SOS distress signal
In the early stages of radio broadcasting, the sound of a help alert was developed individually by each communications provider. Since each company sought to monopolize a new niche in the market and installed its own radio beacons with a unique message on ships, there was no one-size-fits-all warning message.
History of the SOS signal
Also, company managers prohibited receiving notifications from beacons of other manufacturers, and this practice had negative consequences. However, in 1906, at a conference on radiotelegraphy, a single, simple sound consisting of three dots, three dashes and three more dots was chosen. And so that it would not get lost in the air, a silence regime was established every half hour for 3 minutes per day. It is worth noting that, contrary to the prevailing stereotype regarding the decoding of SOS in Morse code, this combination is not an abbreviation.
TROUBLE SIGNALS
Home / Publications / Literature / Bookshelf / V.A. Dygalo. Russian fleet. Three centuries in the service of the Fatherland“A disaster is an event with unfortunate, tragic consequences.” Behind this laconic definition is a linguist, doctor of philological sciences, professor, author of the “Dictionary of the Russian Language” SI. Ozhegov stands thousands of human destinies, closely intertwined with courage, cowardice, betrayal and nobility. It hides a secret behind itself, sometimes never discovered and even more terrible for its unsolved nature.
Particularly dramatic is the struggle of man with nature beyond his control, primarily with the raging water elements.
How many dead ships lie at the bottom of the oceans and seas?
American oceanographers tried to answer this question. According to their estimates, at least one million. If we assume that people have been engaged in navigation for more than two thousand years and accept that the average loss is about 500 units, then we will get the mentioned million dead ships. Thus, for every 40 square kilometers of the seabed area of the seas and oceans, there is one lost ship.
At the bottom of the seas and oceans rest ancient Roman ships, caravels and galleons of Spanish and Portuguese conquerors, hiding in their holds the gold of Peru and the silver of Mexico, frigates of the English colonialists with a cargo of precious stones from India, ivory and ebony from Africa, ships of seafarers from the Middle and Far East. The East with corals and pearls, light brigantines of pirates, whose holds are filled with stolen goods, and modern ships with various cargoes.
Despite the technical improvement of sea vessels, their equipment and the application of various navigation safety rules, the number of shipwrecks at sea remains significant. According to foreign data, in 1979-1983 alone, 1,199 large ships with a total gross tonnage of 8.5 million registered tons perished. In 1979 alone, over two thousand people died on large ships.
The reasons for such a large number of shipwrecks are extremely varied and individual in each case. At the same time, among them you can find typical ones and classify them by type of incident (fire, leak, throwing a ship onto rocks in stormy weather, improper loading of the ship and its capsizing under the influence of waves and wind due to loss of stability, collision with other ships, etc. Further).
The death of a ship from any of the above reasons reminds us that in navigation, as in any field of activity, in addition to technical factors, the human factor also plays a very important role, for no technical achievements and improvements can replace the art of navigation and the sense of high responsibility of the crew for the ship entrusted to him and human lives.
In most cases, the crew themselves are unable to save their ship and call for help by sending distress signals.
It can be said without exaggeration that since the first known shipwrecks of ships of the ancient Cretans, Egyptians, and Phoenicians (2000-1500 BC), the distress signal has been the most important signal.
From the history of maritime signal production, many different methods of sending distress signals are known. For this, the following were used: drums, a bell, a siren, a bugle, a horn, smoke from a burning barrel of tar, oil or fuel oil, the fire of a fire lit on a special brazier on the deck of a ship, flags of various dark colors in combination with a ball, slow raising and lowering of hands to the sides, and at night - the same raising and lowering of lit oil lanterns. Bottle and pigeon mail were used, but news sent in this way reached someone or the addressee when those calling for help had already died.
With the invention of gunpowder, single periodically repeated cannon shots or volleys from muskets and other guns, the launch of powder rockets, flares, usually red, and so on, began to be considered distress signals. With the advent of radio, radiotelegraph and radiotelephone distress signals began to be used, supplemented in recent years by the reception and transmission of signals through artificial Earth satellites (AES).
The classification of distress signals seemed to reflect the time of their appearance. If pigeon or bottle mail were known in ancient times, then the use of satellites for relaying distress signals dates back to the 70-80s of the 20th century.
Currently, all ships that have radio stations, and all coast stations associated with ships, are required every hour for six minutes at a set time to stop all transmissions and listen on the radiotelegraph distress frequency - 500 kHz, recognized in 1927 as a single international frequency for transmitting distress signals by radiotelegraph. This period of silence occurs 48 times a day. Radio operators are waiting to see if the SOS distress signal will sound on the air.
In radiotelephone mode, distress signals are transmitted every hour on a frequency of 2182 kHz from zero to 3 minutes and from 30 to 33 minutes.
In Russia, the transmission of information about accidents using radio was first carried out in 1899 by the inventor of radio and his assistants. In the autumn of 1899, the battleship Admiral General Apraksin was blown onto the rocks off the island of Gotland (Baltic Sea) by a strong wind. For a successful rescue, fast and reliable communication between the emergency ship and the shore was necessary. Such communication using radio was carried out by A.S. Popov. The rescue operation was a complete success. In 1903, a radiotelegraph conference was held in Berlin, the delegates of which were supposed to develop a radio communication system between ship and coastal radio stations. It was attended by representatives of eight maritime powers, including Russia. Moreover, among the Russian delegates was A.S. Popov. At the conference, an attempt was made to establish a single radio distress signal. First, the letter combination SSSDDD was proposed. However, the English radiotelegraph service offered its own distress signal, SOD, for ships equipped with radio equipment of its system, which many found convenient. But the delegates did not come to a common decision. Therefore, in October 1906, also in Berlin, a new conference was held, at which 29 countries were already present. The German delegation proposed the combination SOE (three dots - three dashes - one dot). However, this proposal was rejected, since the letter E, in Morse code, is transmitted by one dot and can be missed during long-distance reception or overloaded airwaves. In the process of discussing various options, it was proposed to use the German version - SOE - replacing the letter E with S. The result was a very rhythmic SOS signal, converted in Morse code as three dots, three dashes, three dots. All signal characters are transmitted simultaneously, without pauses between letters. The person who proposed this signal was a musician and believed that such a letter combination was the most euphonious of all those proposed.
Experts were invited - musicians, psychologists, physicists - and they confirmed the acceptability of the proposal.
Although the SOS signal was composed artificially and was not some kind of abbreviation, nevertheless, later it began to be deciphered as “Save our souls” or “Save our ship”, and the Russians - as “Save from death."
Due to the controversy surrounding the use of various radiotelegraphs on ships, the SOS signal as an international distress signal was introduced only in 1908. However, even in 1912, the senior radio operator of the sinking Titanic, Philippe, initially broadcast the COD distress signal, since the ship was equipped with a Marconi radio. Second radio operator Bride advised Philipps to transmit the SOS signal, approved by 28 participants in the Berlin Conference a month after its end - November 3, 1906.
“You may never have to pass it on again,” Bride added. Philippe began transmitting an SOS signal. This signal was heard and understood, and many ships rushed to the dying liner to help.
At the International Washington Radiotelegraph Conference in 1927, a ban was established on broadcasting on the radiotelegraph distress frequency (500 kHz), except for broadcasts related to the emergency. The conference also established a distress signal for transmission by radiotelephone from ships and aircraft - "Mayday" (in French - "Help me"), in English - "May Day"), as well as a frequency for this signal - 2182 kHz.
On the distress frequency, in addition to the SOS signal, it is allowed to transmit information about floating mines, abandoned and sunken ships, drifting buoys, banks, shoals, rocks, and volcanic formations. The same frequency can be used to report shallowing of channels and fairways, obstacles not shown on maps and navigation directions, malfunctions of navigation equipment, changes in the operating mode of beacons, lights, radio equipment, that is, everything that is associated with an immediate threat to the safety of navigation .
The Radiotelegraph Conventions of 1906 and 1927 are one of the very few international forums in the history of which issued documents that have not undergone any changes over time.
The International Maritime Organization adopted the International Code of Signals (ICS) in 1965.
The sinking of the French steamship Saint Philibert on July 31, 1951, with a sharp list to starboard. The ship sank so quickly that they didn’t even have time to give an SOS signal.
It came into force on April 1, 1969 and is designed to maintain communications in cases of distress or danger to navigation. MCC is applicable for signal production by all communication methods. Signals in the MSS are divided into three main groups: one-letter, two-letter and three-letter. Two-letter signals constitute the general section of the MCC and are used to transmit distress messages (for example, distress signal - NC). Despite the widespread use of radio distress signals, the rescue of shipwrecked victims is still largely dependent on a number of accidents. Rescuers can come to the rescue if they receive a distress signal and know the coordinates or at least the area of the accident. However, an explosion on a ship can damage equipment and antennas, a fire can cut off the path to the radio room, or a disaster can occur in an area of the World Ocean where there are no ships or planes nearby and where radio waves cannot reach. In all such cases, the ship is doomed to an unknown death.
With the advent of satellites and the expansion of their capabilities, research began in a number of countries with the aim of creating, at the national and international level, space systems for receiving emergency signals and relaying them to the Center for collecting and processing data on emergency situations in the World Ocean.
The current space means of search and rescue at sea are international in nature and are established by relevant international agreements. For example, the USSR, USA, Canada and France took part in the creation of a special international space system KOSI AS - SARSAT, designed exclusively for receiving distress signals. Then they were joined by Great Britain and Norway. The name of the system was formed from the combination of the Soviet program KOS-PAS (Space System for the Search of Emergency Ships and Aircraft), carried out since 1978, and the American-Canadian-French program SARSAT (Search and Rescue Satellite), also launched in the 1970s. In its final form, the CBS PAS-SARSAT system consists of three Soviet and two American satellites located in circular orbits in such a way that each of them listens for distress signals from an altitude of 1,000 kilometers in a circle with a diameter of 6,000 kilometers. The accuracy of determining the coordinates of the accident site is one to three kilometers. Complete coverage of the entire Earth's surface is carried out every three hours. The so-called points for receiving information from satellites were built by Great Britain, the USSR and Norway, and Bulgaria, Germany and Finland created and put into operation emergency radio beacons, with the help of which distress signals can be transmitted via KOS-PAS-SARSAT. Denmark, Brazil, New Zealand, Algeria, Saudi Arabia, Switzerland, Australia, Spain, Sweden and a number of other states intend to join the system.
The need for a new system for detecting ships and aircraft in distress is extremely great, especially considering that over 75,000 large ships, several million small (with a cargo capacity of less than one hundred tons) fishing vessels, yachts, pleasure boats, various platforms and other floating objects float in the World Ocean. , and the world civil aviation numbers more than 250,000 different aircraft, including a large number of private ones, especially in the USA and Canada.
It is not uncommon for many of these vessels to end up in emergency situations. Thus, in the United States between 1972 and 1977, 4,800 vessels suffered accidents in the fishing fleet alone. And 374 people died on them. In Japan, over five years (1977-1982), 11,000 ships sent distress signals, of which 1,919 died. Operation of the system during the first five years (1982-1987) revealed a number of its advantages. Suffice it to say that during this time, over 800 people were saved with its help. Thus, in the period between September 10 and October 1, 1982, when there was only one Soviet satellite in orbit - KOSP AS-1, with its help the coordinates of three aviation and one sea accidents were determined. The number of such determinations would be tens and hundreds of times greater if ships and aircraft were equipped with emergency buoys of the appropriate design. The very first case in the history of KOS-PAS-SARSAT was the rescue of three Canadians from the province of Ontario who crashed on a personal light aircraft, a Cessna 172. The Cicada navigation equipment installed on COSPAS-1, on September 9, 1982, recorded a weak distress signal coming from a deserted mountainous region of Canada (British Columbia). The nearest populated area from the accident site was more than 160 kilometers away. Through the Soviet Space Communications Center in Moscow, a distress message was transmitted to Canadian rescue services, which sent search helicopters to the area, found the crashed aircraft and people seriously injured, and took them to hospital. If previously it took on average several days or even weeks to establish the coordinates of the disaster site (for example, two Canadian jet fighters that made an emergency landing in Alberta were discovered only six weeks later), now it only takes a few hours. If there is only one satellite in orbit, then the reception and transmission of the distress signal will occur in the interval from 5.8 to 21.2 hours, with four to five satellites - in the interval of 2 hours, with nine satellites - no more than 1 hour.
The use of the COSPAS-SARSAT system dramatically reduces the time it takes to search for victims in distress, which is of fundamental importance both for saving lives and for checking all distress signals by search and rescue services. The reduction in search and rescue time also affects the survival rate of people in distress. Thus, with an operation lasting about 16 hours, the survival rate of victims does not exceed 40 percent; if help is provided after 24 hours, the average survival rate is 25 percent, and if the duration of search and rescue efforts is about 12 hours, then the probability of survival will be 50 percent. The use of space means for searching and rescuing shipwrecked ships will not only save a significant number of people in distress, but will also provide a significant economic effect.
The COSPAS-SARSAT system has already received official approval from the International Maritime Organization, which has obligated all ships, starting in 1993, to have emergency radio beacons (ARB-406) of this system on board. By 2000, the total number of beacons placed on ships, aircraft and other objects exceeded a quarter of a million.
In practice, the COSPAS-SARSAT program demonstrates great capabilities, and thanks to it, to date, timely assistance has been provided to hundreds of ships and aircraft and many, many people in need.
Modern ships of our fleet are equipped with the latest equipment, and their safety equipment, naturally, cannot be compared with ships of the distant past. However, even in our time, accidents and disasters at sea due to various reasons often occur. And yet, the cause of most of the maritime disasters that made a splash in their time was not hurricanes, reefs and fogs with icebergs, but the people themselves, who made mistakes in the design, construction of ships or when managing them. Sometimes these errors in ship accidents appear simultaneously, and then the disasters become larger-scale and lead to even greater casualties. Suffice it to recall the death of the English giant transatlantic passenger liner, which sank on April 15, 1912. It was because of the violation of the project during the construction of this “unsinkable” (as it was written in the advertisements) giant and because of violations of the requirements and laws of navigation that out of 2,207 passengers and crew on board, 1,507 people died.
The human factor showed itself to an even greater extent in the collision of the Black Sea Shipping Company passenger liner Admiral Nakhimov with a capacity of more than 17,000 registered tons and the bulk carrier Pyotr Vasev with 30,000 tons of barley. The tragedy occurred in Tsemes Bay on the night of August 31 to September 1, 1986, with full visibility and waves of no more than two points. 423 people from among the passengers and crew of the ship died. The disaster occurred due to the fault of the captains of both ships, who violated all possible international rules for preventing collisions at sea (COLREGS).
Since ancient times, in case of disasters at sea associated with cargo and passenger ships, captains, when rescuing people, followed the principle: “Women and children first.” More than 150 years ago, on February 26, 1852, the British steam troop transport Birkenhead, en route from Simonstown to Cape Town, struck an uncharted underwater rock off Cape Danger. There were 648 people on board - mostly soldiers and their families.
The ship stayed afloat for less than half an hour. In an atmosphere of panic, the soldiers were placed on the upper deck under guns. Captain Robert Salmond's "Women and Children First" team! Over the years, it has become an unwritten law for sailors all over the world. 193 passengers were saved then. There was not a single woman or child among the 455 dead.
This tragic incident was glorified by Rudyard Kipling in the poem “Both Soldier and Sailor,” included in his famous collection “The Seven Seas” (1896). Since then, the reef on which the transport hit has been called Birkenhead Rock.
Forward Contents Back
How to send a distress signal
To attract the attention of rescuers, many different ways are used to signal SOS in Morse code. They were developed by inventive sailors and military personnel. There are several categories of distress command, which we will cover below, depending on the type of situation you find yourself in. However, first you need to understand how the SOS signal sounds in Morse code.
Figure 2. This is what an international distress signal looks like in Morse code
As we mentioned above, the distress call sign consists of an easy to remember and recognizable combination: 3 dots, 3 dashes, 3 dots. You can listen to how SOS sounds correctly in Morse code on various educational resources or videos.
Now let's talk about how and with what help to send a warning about danger in various conditions.
Sound: beeps, shots, knocking and other sounds
An SOS notification in Morse code is most easily reproduced using an audible alert on a record player, portable speakers, telephone, or other device with a speaker. The attention of the rescue service will be attracted by sounds played loudly enough several times in a certain rhythm. Also, shots will be clearly audible at a great distance. However, in order not to waste ammo, you should carefully listen to how SOS sounds in Morse code in training videos and practice in advance (Figure 3).
If you know that rescuers are already close to you, a whistle or car horn will also come to the rescue.
How to sound the SOS signal in Morse code? If everything is clear with whistles and horns, then what about signs made from a firearm or a knock?
It's simple: you can send an SOS signal in Morse code by knocking using the intervals between sounds:
- Give 3 knocks with short pauses between them, 3 with long ones, and again 3 with short ones.
- Before knocking SOS in Morse code again, pause for about one minute.
- To send a disaster alert, you can use a variety of methods and objects - it depends only on your resources and ingenuity. The main thing to remember is that there must be a one-minute pause between notifications so that rescuers can recognize the SOS signal in Morse code.
Figure 3. Means for sounding a distress signal
It is advisable that the sound be directed in the direction of the wind - this is how it will travel the farthest. High obstacles in the path absorb the power of the SOS sound in Morse code.
Light: flashlight, flash, sunbeam
There are situations when a person has nothing to send an audio message, or it is necessary to notify about a disaster without unnecessary noise. In this case, you can send an SOS signal in Morse code using light. Remember that it is better to use light sources in the dark - this way they will be much more noticeable (Figure 4).
Save our souls! How the international SOS distress signal was invented
On October 3, 113 years ago, at the First International Telegraph Conference in Berlin, it was decided to come up with a universal way to notify about disasters. And, oddly enough, the SOS distress signal, known to many from action films, turned out to be not the only or even the first option. Why exactly he has gained a foothold - read in the column of our columnist Nikolai Grinko.
Photo: depositphotos/Logray
At least a dozen people are considered the inventors of radio. Almost every country in the world has its own contender: Thomas Edison, Nikola Tesla, Heinrich Hertz, Edouard Branly, Landel de Mouroux, Jagadish Chandra Bose, Alexander Popov. One can argue endlessly about which of them was the first, but all of these, without exaggeration, great scientists are considered the “discoverers” of radio waves - that’s all.
None of them could listen to music on the radio - they simply discovered another physical phenomenon. But the Italian physicist Guglielmo Marconi was the first to find a real application for these waves - it was he who realized that information could be exchanged using radio. True, he was also very far from the charts and talk shows.
He realized that the noise and crackling that the first transmitters sent into the air needed to be structured by encoding the alphabet. Simply put, Morse (according to some sources, not on his own, but with the help of his colleague Alfred Weil) came up with the code that we today call Morse code.
The invention caused a lot of noise at that time: it’s simply incredible - you can send instant messages even to another continent! Perhaps in scale it was comparable to the advent of the Internet. Of course, sailors immediately began to use Morse code: they needed to exchange information as quickly as possible, especially in unforeseen situations.
Distress signals existed before, but they were transmitted using semaphore flags, lights, or even a bell. It is clear that it is impossible to send such a message over a long distance. Radio waves are capable of delivering a message at the speed of light to the other end of the Earth.
Photo: depositphotos/Klanneke
At first there were no general rules for sending a distress signal, and ship radio operators asked for help in plain text (something like: “Help, we are in distress, send help!”). But this method required a huge amount of time, which is not available at the time of the disaster. On October 3, 1906, at the First International Telegraph Conference in Berlin, it was decided to come up with a universal signal.
Various organizations offered their own options. For example, the letter abbreviation CQD (“Come Quick, Danger” - “Go faster, danger”). But as a Morse code, this configuration had a rather complex appearance. In the end, the dispute was put to rest. More precisely, several dots and dashes at once.
Translated from Morse code, three dots are “S”, three dashes are “O” and again three dots are “S”. And only then were various decodings of this combination of letters invented: “Stop Other Signals,” “Save Our Souls,” and so on.
Without exaggeration, the SOS signal saved hundreds of thousands of lives. There is a version that the radio operator of the sinking Titanic was the first in the world to submit it, but this is not at all true. In fact, this happened earlier when the American steamship Arapaoe lost steam on August 11, 1909 and drifted en route from New York to Jacksonville. The signal was received by the United Wireless Telegraph Company station on Hatteras Island in North Carolina and forwarded to the steamship company's offices—the first documented use of an SOS signal.
Photo: depositphotos/Logray
Today SOS has practically fallen into disuse. And this is not surprising: almost no one uses Morse code. Ships, planes, and space stations use digital satellite communication channels, through which, in the event of a disaster, much more information can be transmitted in less time. And yet, the signal “three dots, three dashes, three dots” is worth knowing for everyone, just in case. Of course, it would be better if it was never needed at all, but you never know. The SOS signal can be transmitted by knocking, beeping, shots, a sunbeam or a flashlight - and they will definitely understand it and come to your aid.
There is a story about a remote hotel that was taken over by criminals, cutting off all communication lines. Then the employees came up with an interesting move: on each floor of the building they hung out several sets of bed linen to dry in the following order: three pillowcases, three duvet covers, three pillowcases. Police passing by noticed the signal and sent an armed squad to the hotel.
Most likely, this is just a story. Although…
Grinko Nikolay
