Enlgish Russian Mail Us Site Map Search Page

   4x/4z    HAM radio    Gallery    Links catalog    Handbook    Discover Us    login
Select laguage Home > Gallery > Stories

"'SOS,' 'CQD' and the History of Maritime Distress Calls"

This month we are going to diverge a little from talking about wire and wireless artifacts and talk about wireless telegraph distress signals.

Mystery, intrigue as well as misinformation surrounds the origin and use of maritime distress calls. The general populace believes that "SOS" signifies "Save Our Ship." Casual students of radio history are aware that "CQD" preceded the use of "SOS." Why were these signals adopted? When were they used? Why did one replace the other? What is one likely to find by digging a little deeper?

The practical use of wireless telegraphy was made possible by Guglielmo Marconi in the closing years of the 19th century. Until then, ships at sea out of visual range were very much isolated from shore and other ships. A ship could vanish from the high seas, and no one would know until that vessel failed to make a port connection. Marconi, seeing that wireless would not compete with wire telegraphy for land based communication, concentrated his efforts on ship to shore communications. Ships equipped with wireless were no longer isolated.

The first use of wireless in communicating the need for assistance came in March of 1899. The East Goodwin Lightship, marking the southeastern English coast, was rammed in a fog in the early morning hours by the SS R. F. Matthews. A distress call was transmitted to a shore station at South Foreland and help was dispatched.

By 1904 there were many Trans-Atlantic British ships equipped with wireless. The wireless operators came from the ranks of railroad and postal telegraphers. In England a general call on the landline wire was a "CQ." "CQ" preceded time signals and special notices. "CQ" was generally adopted by telegraph and cable stations all over the world. By using "CQ," each station receives a message from a single transmission and an economy of time and labor was realized. Naturally, "CQ" went with the operators to sea and was likewise used for a general call. This sign for "all stations" was adopted soon after wireless came into being by both ships and shore stations.

At the first international congress of wireless telegraphy in 1903, the Italians recommended the use of "SSSDDD" to signal an emergency. "D" had previously been used internationally as the signal for an urgent message. The origin of "S" is not known, but it may have come from the first letter of the word ship, indicating a ship in distress. The sending of "SSSDDD" would signal all other stations to stop sending and leave the channel open for emergency traffic. Though discussed, it was not adopted. Deciding on a distress signal was put on the agenda for the next meeting in 1906. "DDD" would later be adopted for the silent signal, indicating all stations must cease sending.

In 1904, the Marconi company filled the gap by suggesting the use of "CQD" for a distress signal. It was established on February 1 of that year by Marconi Company's circular No. 57. Although generally accepted to mean, "Come Quick Danger," that is not the case. It is a general call, "CQ," followed by "D," meaning distress. A strict interpretation would be "All stations, Distress." In the U.S. Senate hearings following the Titanic disaster, interrogator Senator William Smith asked Harold Bride, the surviving wireless operator, "Is CQD in itself composed of the first letter of three words, or merely a code?" Bride responded, "Merely a code call sir." Marconi also testified, "It [CQD] is a conventional signal which was introduced originally by my company to express a state of danger or peril of a ship that sends it."

At the second Berlin Radiotelegraphic Conference of 1906, the subject of a distress signal was again addressed. The distress signal chosen was "SOS." (The American distress signal "NC" for "Call for help without delay" was not adopted, although it remains as the international flag symbol for distress to this day.) Popular accounts portray the adoption of "SOS" as being derived from "SOE," which the Germans had used as a general inquiry call. These accounts suggest there was objection because the final letter of "SOE" was a single dot, hard to copy in adverse conditions. The letter "S" was substituted accounts say, for three dots, three dashes and three dots could not be misinterpreted.

Popular accounts of the origin of "SOS" fail to mention that the Germans had used "SOS" for a distress signal. They adopted the signal "SOS" for distress as well as "SOE" for inquiry on April 1, 1905, a year before the Berlin conference. The Electrician, May 5, 1905 published "German Regulations for the Control of Spark Telegraphy" which stated:

"...- - -..., "Distress" signal (Notzeichen). This is to be repeated by a ship in distress until all other stations have stopped working."
Unfortunately, the 1906 Conference proceedings do not give an account of the discussions nor the origin of SOS. The proceedings merely specify what the signal will be. In the Service Regulations Affixed to the International Wireless Telegraph Convention, paragraph 6a, "Signals of Transmission" states::
"Ships in distress shall use the following signal: ...- - -..., repeated at brief intervals."
Next >>