The "unsinkable" ship had the most powerful wireless system at the time. What happened?
The Titanic's wireless signaling system was so strong it reached shore stations.
Despite numerous distress signals sent out, more than 1,500 people aboard died.
Radio experts point to communication technologies that could have saved many more.
"Come at once. We have struck a berg." The Titanic's radio engineers sent this emergency message and many like it in Morse code wirelessly to anyone listening.
Two employees of Marconi, the company that made the system, operated the radio. It was the most powerful system of its kind, and the clear night helped the signal go far.
Many ships did receive the call. So did land-based stations in the United States and Greenland. Radio operators at the time were also skilled at transmitting messages quickly in code -- 80 to 100 words per minute. With such capabilities, what went wrong?
For starters, Titanic's communications system had its limits.
The transmitter was designed to send dots and dashes over a specific frequency that accommodated lots of other ships. Receivers on that frequency, whether on other ships or land-based stations, picked up the dots and dashes to get the message. To ensure the identity of the senders, each ship had a unique call sign -- the Titanic's was "MGY."
"These were sort of souped-up spark machines," Bill Emery said, describing the Titanic's transmitter. Emery is a physical oceanographer, an aerospace engineering sciences professor at the University of Colorado Boulder and an IEEE Geoscience and Remote Sensing Society member.
Not very sophisticated by today's standards, but wireless radio communication in those days was as popular as the Internet today. But not everyone had their own iPhone. Instead, Marconi radio operators Jack Phillips and Harold Bride spent a great deal of time transmitting and receiving telegrams for the passengers.
Constant communication from high-profile passengers kept the operators busy said Charles Cushing, the head of a naval architecture firm in New York who teaches at the UN's World Maritime University and recently attended the International Marine Forensics Symposium in Washington, DC.
Passenger communications were so pressing that Phillips got irritated when the radio operator from the Californian, a ship nearby, interrupted one of his transmissions with a now infamous courtesy message saying that they'd encountered ice. Phillips angrily signaled back, "Shut up!" The incoming message was jamming him, and he was busy.
The 5,000-watt Marconi system operated with a fairly low frequency, which allowed its signal to travel long distances, especially at night. And on that fateful night, the skies were clear. Transmission went farther without atmospheric distortions from their location in the middle of the North Atlantic.
"When they struck the iceberg, had they not had this facility on board, their distress messages that went out might have reached nearby ships but they would have never reached places where they did reach," said Bill Hayes, a lifelong broadcaster, director of engineering and technology for Iowa Public Television and vice president of the IEEE Broadcast Technology Society.
The emergency signal was so strong it reached the mainland United States and Greenland's base stations, which were then capable of relaying the message to others. Those land-based services, Hayes said, formed a communications chain.
As the Titanic was sinking, the radio operator had to repeat the emergency message for each ship that he was talking to since they could only catch pieces of it, Emery said. The emergency went out as both "CQD," a distress code used by Marconi operators, and the standard "SOS."
"He has to tell the same story: 'We ran into an iceberg, we're sinking, we need immediate assistance.' Apparently a lot of them don't understand what's going on," Emery said.
Unlike modern communications where it's possible to dial a phone number and reach one person, during the Titanic disaster everyone is signaling at the same time. "With the wireless, essentially it's a party line," Hayes said. Communications chaos ensued.
The answer to one question might be the opposite from the answer to another ship's question, but the messages are all being transmitted at once.
The Titanic's exact position was also unclear. During emergency communication with other ships at the time, the position is given out numerous times and then corrected. Even the corrected position was about a dozen nautical miles from where the wreck would be uncovered in 1985.
"The technology was there, but the records and the standards of having people monitoring the radio weren't in place," Cushing said.
Books have been written about the Californian, one of the ships closest to the Titanic when it sank. The Californian's radio operator, Cyril Evans, didn't send his ship's position in the message about encountering ice, nor was the message prefaced by "MSG," which would have indicated that it needed to go to the Titanic's captain. After being told to shut up, Evans simply turned off his transmitter and went to sleep.
"It appears that the ice warning that wasn't delivered to the captain basically didn't come through with the proper coding," Hayes said. The message came in like any other traffic.
A similar incident happened during the attack on Pearl Harbor, Hayes added. Atmospheric conditions made radio problematic so a telegram warning was sent from Washington, but it wasn't marked urgent. The message was delivered after the attack had ended. delivered
The Titanic disaster prompted a number of changes, including in emergency signaling. Guglielmo Marconi himself even came up with an automated distress alarm that could be triggered when it received four or more dashes lasting four seconds from a ship in trouble.
When it was enacted in 1934, the Communications Act included provisions for distress signals, requiring that frequencies be reserved for emergencies and that a licensed radio operator be listening for such a signal.
Today, ships in distress now have a clear channel for communication, Hayes said. Direct responses to that ship are communicated on that one channel and all other coordination with ships on the way or ships and their bases happen on separate channels, leaving the emergency one free.
Ships continue to monitor emergency channels, but it's done automatically and the crew doesn't need to know Morse code. When an emergency does occur, lights flash and an alarm rings.
Over time, radios became more and more powerful. "Then of course came satellite communications," Cushing said. "You know exactly where the ship is and where the potential rescuers are." Satellites solved numerous problems at sea.
Emery pointed out that now the U.S. Coast Guard's "Search and Rescue Planning System," known as SAROPS, can model different scenarios and project where survivors and vessels will drift from a wreckage site in a given amount of time. Since being deployed in 2007, SAROPS has been used to find missing people and save lives at sea.
Hayes has thought about what would have happened if the Titanic were setting off in 2012 instead of 1912. First off, he said, with radar the ship could have seen the iceberg from 70 or 80 miles away.
Assuming that the ship did end up hitting the iceberg in spite of the radar warning, communications would have been much more targeted and informative.
"They would have had an exact position. They'd be using GPS so they'd be accurate to within 30 feet of where the ship actually was," he said.
Within minutes of the report that it was sinking, rescue aircraft would have been dispatched from the closest land bases. They would have dropped survival gear, rafts and other emergency equipment within an hour or an hour and a half of the initial report. hour
Typically there isn't a single cause for a disaster, Hayes said. "There's generally a sequence of failures. Some of those failures probably happen all the time, but never in that sequence. When they happen in that sequence, that's when you get a disaster."