GALLERY
The Coast Guard has recovered small pieces of wreckage from the waters off Nantucket

November 4, 1999
Web posted at: 10:57 a.m. EDT (1457 GMT)

In this story: Seas too rough for recovery Thrust reverser deactivated Malfunction considered unlikely Earlier 990 pilot: plane flew well RELATED STORIES, SITES

NEWPORT, Rhode Island (CNN) -- New radar data reveal EgyptAir Flight 990 started to climb after dropping 17,000 feet in a matter of seconds, then entered a fatal plunge, apparently breaking up before it crashed into the sea, killing all 217 aboard, radar experts said.

The Cairo-bound jet plunged into the sea off Massachusetts less than an hour after leaving John F. Kennedy Airport in New York on Sunday.

Hotlines EgyptAir information lines: In the U.S.: (800) 243-1094 Outside the U.S.: (202) 245-2244 (202) 244-1460 (202) 418-3690 FBI Information line: 1-800-473-4761    VIDEO Correspondent Ann Kellan looks at the role flight recorders can play in the investigation of a crash such as that of EgyptAir 990 Windows Media 28K 80K CNN's Frank Buckley talks with family members of victims of the crash. (November 3) Real 28K 80K Windows Media 28K 80K Grief counselors say they learn something new about how to comfort people after every disaster. CNN's Bill Delaney reports. (November 3) Real 28K 80K Windows Media 28K 80K CNN's Mike Boettcher looks at thrust reversers and how they might cause a plane to crash. (November 3) Real 28K 80K Windows Media 28K 80K Use the arrow buttons below to scroll through the video gallery.    Windows Media Real    28 K 80 K     ALSO American Muslims call for Defense Department investigation of EgyptAir crash Depth comparison of various crashes Passengers and crew on EgyptAir Flight 990     MESSAGE BOARD Message Board: Plane crashes

Investigators had previously said preliminary radar reports showed the plane plummeted directly into the ocean from an altitude of 33,000 feet. But they now believe that the descent was not direct.

"After descending from 33,000 feet to 16,000 feet, the aircraft climbed back to 24,000 feet. The aircraft then entered a rapid descent," National Transportation Safety Board radar specialist John Clark said on Wednesday.

The new data show numerous "primaries" -- images from the airplane picked up by radar -- in an area northeast of the plane's suspected splashpoint, "moving more consistent with the wind," he said.

That could indicate the plane may, at that stage, have been in the process of breaking up.

Vessels combing the ocean off Massachusetts on Wednesday for data recorders from the aircraft suspended their search because of bad weather -- and were not expected to resume work until early next week, crash investigators said.

Winds gusting at 35 mph and waves up to 22 feet have delayed efforts to recover the cockpit voice and flight data recorders. They could provide crucial clues as to what caused the Boeing 767-300 to plummet from the sky.

"It is unclear at this time when we will be able to resume work," NTSB Chairman Jim Hall told reporters.

U.S. Navy Capt. Bert Marsh said seas would probably remain heavy throughout the weekend.

The search has centered about 50 miles southeast of Nantucket Island, where "pings," or electronic signals, from the recorders have been detected.

Although the weather was sunny in Newport, Rhode Island, where search operations are based, the rough conditions at sea forced all but one of the recovery ships to stay ashore Wednesday.

Earlier this week, Coast Guard cutters brought their findings, including pieces of the plane's fuselage and one of its tires, to the naval air station at Quonset Point, Rhode Island, across Narragansett Bay from the Newport Navy base.

Officials probing Sunday's crash also were looking into the possibility that a deactivated engine part called a thrust reverser played a role in the disaster. But, according to several aviation experts, that scenario is unlikely.

As investigators waited for the weather to improve, they collected information about whether one of Flight 990's two thrust reversers might have suddenly activated in flight, knocking the jet off course.

A thrust reverser slows a plane on landing by reversing engine air flow.

An EgyptAir executive confirmed that one of the thrust reversers on the 767 had been turned off before the flight left Cairo en route to the United States.

EgyptAir Vice President for Technology, Megid Al-Masri, told CNN that one of Flight 990's thrust reversers was "deactivated" before the flight left Cairo because maintenance crews there found a hydraulic leak in one of the actuators.

The actuators control the thrust reversal system.

Hall said NTSB investigators would be contacting EgyptAir to review maintenance records that might shed some light on the deactivation.

The flight still met regulations for safe flying, U.S. investigators said, because airplanes are allowed to fly with only one operating thrust reverser.

Al-Masri said the "hydraulic leak" problem was not fixed in Cairo because the airline did not have the correct spare parts. But, he added, the airline planned to repair the problem before the 10-day period allowed under normal international aviation practices.

Pilots who flew the plane on earlier legs also reported a flickering light on an air conditioning system. Two tires were replaced at a stop in Los Angeles where Flight 990 turned around and headed for New York to pick up more Cairo- bound passengers.

Several aviation authorities indicated the deactivated engine part probably did not cause the disaster for a number of reasons: