Searchers face many obstacles, remain confident they'll succeed

Sophisticated equipment could help overcome deep water, currents

The Crash Of Flight 990

November 02, 1999|By Marego Athans | Marego Athans,SUN NATIONAL STAFF

The investigation into Sunday's EgyptAir crash faces a host of obstacles: deep water, scattered debris, strong currents and an approaching storm. But veteran investigators say they're certain that searchers will find enough evidence to determine what caused the jet to plummet into the sea with 217 people aboard.

"I'm confident there'll be a large amount of wreckage recovered. It'll just be a slow, tedious process -- months," said Gene Doub, a former investigator for the National Transportation Safety Board who trains air safety inspectors.

Unlike the crash of Pan Am Flight 103 over Lockerbie, Scotland, where debris fell onto land, and of TWA Flight 800, whose fuselage fell relatively close to shore in 100-foot waters of Long Island Sound, EgyptAir Flight 990 went down in open sea 60 miles off Nantucket, Mass., in 250 feet of water.

Not even the most experienced Navy diver can function long at that depth, said Navy spokeswoman Patricia Dolan.

Last night, investigators reported a first success: Coast Guard ships received a "ping" signal they believe was emitted by one of the plane's "black boxes," which record the pilots' conversations and data on the plane's operating systems.

Sophisticated equipment that can trace the signal and find the boxes is expected to arrive today, but pinpointing the location will be difficult, said Coast Guard Rear Adm. Richard Larrabee.

Retrieving the boxes, which are actually orange, is a top priority, investigators say. The recordings, along with a radar analysis, help investigators decide which parts of the plane they most need to analyze. Sometimes, the boxes are all the investigators need.

"We may be able to go down there and determine [what happened] without bringing anything up," said Karen Moran, spokeswoman for Oceaneering Technologies, a Navy contractor in Upper Marlboro in Prince George's County that has sent a team to the crash site. "Maybe the pilots can tell us the whole story."

Investigators don't need to reconstruct the entire plane or even a section of it, as they did after the 1996 TWA crash, to determine the cause of the accident.

"There's a very high likelihood that they can find those boxes, and armed with those boxes they can quickly tell what sort of event they're looking at," said John Cox, a spokesman for the Airline Pilots Association and central air safety chairman at US Airways. He has been on several teams investigating crashes.

Such sleuthing is easier after the investigation of the TWA crash, Cox said. "They learned some pretty good lessons. If you look back, it's probably one of the most difficult wreckage recoveries that's been attempted, and they were successful."

In the EgyptAir investigation, water depth poses the greatest challenge. At twice the depth of the site of the TWA crash, it's the deepest water searchers have worked in in recent aviation history, said Navy spokesman Mark McDonald.

At 240 feet, a diver has only 30 to 40 minutes from the time he leaves the boat before he must begin his ascent, which takes about an hour as he stops to acclimate his body to the changing depth.

Among the other challenges of the investigation will be to get a large freshwater tank near the crash site to ensure that wreckage hauled out of the salt water is washed off immediately to prevent corrosion.

Veteran investigators say that even the hardships of a stormy New England November on the open seas can be overcome with sonar-equipped machines and robots that can search the ocean floor at depths humans cannot stand. The machines can take pictures, transmit images to video screens aboard the ship, and even secure wreckage using remote-controlled arms, cages and ropes.

"Those are our eyes," Moran said. "Those pieces of equipment can do what a diver cannot do, which is stay down. They don't get cold. They don't get tired. They don't need to eat. They don't get decompression sickness. That's what makes them so valuable in cases like this because we have to work so fast."

The crew from Oceaneering Technologies, which has worked on several high profile crashes, such as those of TWA Flight 800 and John F. Kennedy Jr.'s plane in August, is expected to arrive at the crash site today. Also expected are two Navy ships, the Mohawk and the Grapple, which together will carry the sophisticated search equipment and 116 crew members, including 30 divers.

Once the Coast Guard has searched the ocean's surface for debris and isolated the area that needs to be searched, one of the Navy ships will tow a "pinger locator," a triangular machine that looks like a sting ray.

Next, a Side Scan Sonar machine looks for debris on the ocean floor. Then, the recovery crew sends out remote operated vehicles -- machines that look like big yellow crabs -- which have sonar, cameras, mechanical arms and umbilical cords that connect to the ship. In addition to taking pictures and transmitting images to technicians on the ship, they illuminate the debris, helping divers see.

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