Lessons worth remembering
- By Dan Caterinicchia, Dan Caterinicchia
- Sep 16, 2002
Sifting through the rubble at the World Trade Center last September was among the most tumultuous search and rescue operations imaginable. Not only did first responders have to deal with the trauma associated with the horrific scene, but they were also unable to get more than a few minutes of work done before an alarm would go off requiring the evacuation of an unstable building or dangerous area.
Michael Albarelli, director of homeland security at the Army's Communications-Electronics Command in Fort Monmouth, N.J., said Cecom personnel arrived in New York City only two days after the terrorist attacks, armed with a handful of tools used to search for survivors and help eliminate false warnings about the impending collapse of nearby buildings, which were hindering the rescue operations.
Cecom teams were called in after Federal Emergency Management Agency employees at the scene suggested using Army technologies to aid in the search and rescue operations, he said.
Most of the tools are traditionally used for search and destroy missions, but they were easily adapted to the rescue efforts with some minor modifications.
"The technologies used for search and destroy are really no different than search and rescue," Albarelli said. "Operationally they are different, but the technology is the same."
The idea of bringing in Army technology to help with recovery efforts is one that could bear fruit in the years ahead, Army officials say, giving new tools to FEMA and other agencies dealing with crises and providing valuable lessons.
Watching for Motion
When the call for help went out, at least 27 Cecom personnel came armed with everything from classified signal equipment to detect wireless phones in the rubble to a laser-based technology used to detect land mines but modified to monitor the movement of potentially unstable buildings at the scene.
Cecom also flew an aircraft equipped with sophisticated cameras and infrared sensors over the scene, which found two fires raging two stories underground, Albarelli said (see box, Page 37).
Toni Quiroz, former chief of the computer networking branch at Cecom, arrived at the site Sept. 13 and was assigned as team leader to assist in the rescue efforts.
The Cecom team set up sensors in the mezzanine of World Trade Center Building 2 and scoped the area using classified signal equipment, looking for wireless phones that might be turned on and the airplanes' black boxes — the flight data recorders that are so valuable to investigators, said Quiroz, who is now a program manager at CACI International Inc.
"Most, if not all, of the signals were coming from people helping with the rescue," he said, adding that it was a long shot to find a phone with batteries that had survived the collapse and still had enough power to be turned on two days later.
The team managed to get some signals that could have emanated from the black boxes, but it was never determined if they were the recorders, Quiroz said.
"All the factors were really against us finding anything...[and] there were no definite findings with phones coming from the rubble," he said, noting that even if signals were coming from the debris, they could have been bouncing off wireless phones outside the wreckage.
"It was like taking a room full of mirrors and shining a flashlight in," he said. "There were so many signals bouncing back and forth all over the place. It was very, very difficult to pinpoint any one signal."
John Pike, director of GlobalSecurity.org, which monitors space and military programs, agreed that the chances of the Cecom technology helping find survivors were slim.
"Generally, the first few hours are the most critical for rescue efforts," Pike said. "After two days, the prospects of finding survivors start to dwindle."
Rescue teams also used defense technologies to assess the structural soundness of nearby buildings.
Peter Lacko, electrical engineer for Cecom's Night Vision and Electronic Sensors Directorate at Fort Belvoir, Va., was called in to help monitor Building 4 — located about 20 yards from the collapsed towers.
A local construction survey company was managing "transits" to measure the building's movements. Transits are used to measure grade and elevation electronically. They were fixed on a point on the side of the building and checked about every five minutes to see if the building had moved, Lacko said. But the transits could give inaccurate readings because they were unable to filter out vibrations from heavy machinery or other factors in the area.
The readings caused numerous false alarms that required areas to be evacuated for hours at a time. "The search and rescue folks were on for 20 minutes and then off for two to three hours," Albarelli said.
Lacko's team used laser Doppler vibrometers, which send out laser signals that hit pieces of reflective tape and then beam signals back that help workers determine the vibrational frequency of the structure, he said. The tool sits on a tripod and is about 5 inches tall and 12 inches long.
"The laser Doppler vibrometer measures a building's frequency and whether it's vibrating five times a second, or if it moved six micrometers or six centimeters," Lacko said. "It determines how much it's actually moving and at what frequency."
Rescuers were able to home in on the building's frequency because it was different from the ones created by heavy machinery and jackhammers, he said.
The laser Doppler vibrometer was set up about 20 feet from the transit station — where the air horn used to alert personnel of a work stoppage was also kept — and the two tools were used together to help eliminate false alarms. "It gave all the workers in and around that point better security at the time as to whether that building was going to come down," Lacko said. "There was more technology on site to determine if the building was stable. Several different workers thanked us for coming."
Lacko's team was on the site around-the-clock until Sept. 25. "The building was very stable the whole time we were there," and it remained that way until construction crews demolished it, Lacko said.
Pike said modified search and destroy technologies may have uses beyond search and rescue. "At least some of these may have some application in urban combat situations — not to detect survivors in rubble, but to detect enemy combatants."
The technology used last year proved its value, but more technology is needed, Army officials say.
Cecom officials, in particular, believe more should be done to coordinate the work of first responders, civilian agencies and the Defense Department. Rudy Giuliani, former mayor of New York City, was trying to coordinate the efforts of 22 agencies at ground zero and often had 22 radios lined up in front of him, Albarelli said.
Command and control systems also could help those agencies, he said. "In a future major disaster, so many different organizations will be eager to help and do what's right, we need to put a [command, control, communications, computers, intelligence, surveillance and reconnaissance] architecture in place to help align agencies so the responses are connected with one another," Albarelli said. "That's the message we're trying to send forward to the [proposed Homeland Security Department] and all other agencies participating in this."
The military services could also serve as advisers, or providers, of useful technologies to first responders in future efforts, he said. Civilian agencies and state and local governments have tools, too, but when their batteries die or a software update is over, the technology is outdated or gone forever, whereas the military life cycle includes better sustainment and training, he said.
"Command and control and sensors are critical to a major disaster, but civilian communities don't have access to the very sophisticated technologies that the military has," Albarelli said. "All federal, state and local agencies have emergency response [groups], but a lot have limited budgets and don't have the technology to execute when they need to. The Army is spending money on transformational technologies that could be adapted to use for homeland security."