Could New 'Light Radar' Find Missing Jet?
A new type of radar uses photons and could carry more information about an object.
The disappearance of Malaysian Airlines Flight 370 has exposed some of the inadequacies of existing air traffic control systems and posed a compelling mystery of how an airplane can disappear from radar screens without a trace.
In the meantime, researchers are working on new kinds of radar that could provide clues to the next such mystery, radar that uses short bursts of light to produce a signal that can not only detect an airplane mid-flight, but also cover a wider territory and communicate with the plane at the same time.
In today's journal Nature, a team of engineers from Italy published a study about so-called photonics radar, which uses laser to produce the radar signal, which is then transmitted through a traditional antenna.
"We substitute electronics with photonics," said Paolo Ghelfi, a researcher at the National Inter-University Consortium For Telecommunications (CTIM) in Pisa, Italy and an author on the study. "The first reason is to increase the precision and flexibility of the radar system."
Ghelfi says that photonics radar can combine surveillance and communication in one signal. That is something that now requires multiple systems between the plane and the ground, and has befuddled investigators looking for flight 370.
"Having a single system that can do a lot of different things allows us to imagine that maybe we will have in the future a way to collect data about speed and altitude along with what's going on in the cockpit," Ghelfi told Discovery News.
Ghelfi's project, developed along with fellow researcher Antonella Bogoni, is undergoing trial runs at the Pisa Airport to track planes, as well as the port of Livorno, Italy, to track ships in the Mediterranean. The team's PHODIR (photonic-based fully digital radar) was funded by the European Research Council.
According to Ghelfi, a photonic radar system can carry more information about an object, as well as getting higher resolution about the target's shape and altitude.
"One could think about radar system that makes a fast scan of the coverage area, a quick calculation without too much resolution, just to see what is moving around," Ghelfi said. "Then when you see something you want to concentrate on, then you can be more precise in that direction. This is the flexibility we are talking about."
The Italian PHODIR project is not the first photonic radar system, others have been working on similar idea for the past two decades including the Pentagon's Defense Advanced Research Projects Agency (DARPA).
"Their contribution is they have integrated a lot of techniques into a radar system," said Henry Zmuda, associate professor of electrical engineering and computer science at the University of Florida.
Experts say that there are plenty of engineering bugs to be worked out and it will take a few years before photonic radar replaces existing electronic radar systems in commercial aviation.
"The application of photonic technology to RF systems such as radar has been an enduring objective for quite some time," said Mark Smith, chief scientist of the sensors and electromagnetic applications laboratory at the Georgia Tech Research Institute. "The development reported by Ghelfi et al. is a potentially noteworthy contribution in the ongoing evolution of RF-photonic technology. It will be interesting to follow their progress."
As for the missing plane, Ghelfi and the others say new radars may better track planes in-flight, but finding them afterward still requires a lot of guesswork, searchers and, perhaps, luck.
The disappearance of Malaysian Airlines Flight 370 has exposed some of the inadequacies of existing radar systems.
Jan. 20, 2012 -
As investigators try to figure out exactly what went wrong with the capsized cruise ship Costa Concordia off the Italian coast, maritime experts look back at historic maritime disasters so horrific they prompted new rules. "I like to say the laws and regulations are written in blood," said Kevin Gilheany, a consultant based in New Orleans who specializes in maritime safety compliance and spent 20 years in the U.S. Coast Guard. The past is full of tragedy at sea. Gilheany and other maritime experts highlighted these five deadly maritime disasters involving passenger vessels as ones that particularly shocked the public. Here, the MV Princess of the Stars is seen capsized off the coast of San Fernando, Romblon. The ship capsized at the height of Typhoon Fengshen on June 21, 2008. More than 800 people died in the accident.
The Heroes of the Concordia
The Medusa In July 1816, just about everything that could have gone wrong with the Medusa did. The French ship carrying around 400 people, mostly settlers bound for Senegal, ran aground far out at sea due to an incompetent captain. There weren’t enough lifeboats so a large but leaky raft was constructed from masts and rigging that the boats could tow ashore, said Charles Cushing, an expert who heads a naval architecture firm in New York City and teaches annuals course at the UN’s World Maritime University. Officers and politicians got in the boats while settlers and crew boarded the raft. One by one, each boat cut the lines and set off, leaving 146 people adrift. The sun quickly scorched many to death. Cannibalism and mutiny reigned. Only 15 survivors were eventually found alive. "It was a scandal of huge proportions," Cushing said. A graphic painting by the artist Théodore Géricault of the raft now displayed at the Louvre ensured the public would never forget.
General Slocum The Steamboat Inspection Service charged with safeguarding lives at sea had corrupt inspectors back in 1904 who let vessel owners get away with bringing a set of new lifejackets to a boat on the day of inspection and then removing them afterward, Kevin Gilheany said. On June 15 that year, the General Slocum was chartered by a Lutheran church in New York City for a trip to the Long Island shore. A fire broke out shortly after the ship carrying more than 1,300 left the pier. The captain didn't heed calls to stop and kept going, fanning the flames. Few aboard knew how to swim. When the passengers grabbed old lifejackets, the cork had disintegrated to powder but the vests were still weighted with iron, Cushing said. Many passengers were immigrants who didn’t know how to swim, Gilheany said. Adults put the lifejackets on children and threw them into the water, only to watch them sink. More than 1,000 passengers died. The captain was sent to prison and the disaster caused many reforms within the Inspections Service, which is now part of the U.S. Coast Guard. "I use that Slocum disaster in my training when I train captains to understand the legal liability they take on," Gilheany said.
How to Refloat a Capsized Liner
The RMS Titanic Speeding along for its maiden voyage from England to New York, the Titanic struck an iceberg the evening of April 14, 1912. Warnings about icebergs in the area had been ignored. The ship flooded and sank into the deep, killing 1,517. When word spread that the technologically advanced, "unsinkable" ship had gone down, the shock was immediate. Newspapers brimmed with news of the tragedy. There were so many Americans aboard the British ship that the U.S. Senate called for an immediate investigation. The British started their own inquiries as well. Out poured a host of regulations relating to adequate lifeboats, lifesaving equipment, and stability, Cushing said. An International Ice Patrol was formed, which still monitors icebergs to this day, and reports that no vessel heeding the patrol’s published iceberg limit has collided with one. "They fly the big C-130s," Gilheany said. "That's all because of the Titanic."
Wide Angle: Titanic Shipwreck 100 Years Later
The Moby Prince Outside of Italy, the Moby Prince is not that well known, said Giampiero Soncini, a former Italian Navy officer who heads SpecTec Group, which supplies specialized fleet management software. But the aftermath of the horrific disaster had the distinction of being filmed by an Italian TV crew. On April 10, 1991, the Moby Prince ferry collided with the oil tanker Agip Abruzzo in the Port of Livorno. The cause is still contended. Some blame fog, some say the rudder failed, and others say the crew was too busy watching a soccer match, Soncini said. The ferry caught fire and 140 aboard were either burned alive by the flames or asphyxiated on the toxic smoke. The mayday was too weak and miscommunication hampered rescue efforts. Only one man survived. "I happened to watched the live footage and it showed a body melted into the deck -- something I did not know was possible," Soncini said.
The Estonia Ferries that transport cars and trucks with decks close to the waterline are especially vulnerable to capsizing, Cushing said. He compares operating them to walking with a wide, shallow pan filled with water. Any inclination and the water rushes to one side. That "free surface" effect can be deadly. One night in late September 1994, a ferry called the Estonia filled with nearly 1,000 people was speeding along its route from Tallinn to Stockholm in rough, windy conditions. Suddenly the vessel rolled in enormous waves. Water rushed into the hold and the ferry capsized. Despite the convergence of rescue boats and helicopters, the frigid waters claimed more than 850 lives. One of the survivors told the New York Times she heard women screaming out in the sea. An official inspection later showed problems with locks on the bow door, and criticized the crew’s actions when metallic noises should have alerted them to serious problems. "It was the largest disaster in Europe since WWII and it shocked all of us,” Giampiero Soncini said. “Recent construction, good classification society, reputed company and yet more than 900 people died. In 1994!"
Scorned Cruise Ship Captain Not Alone in History