November 3, 1999. Copyright 1999. Graphic News. All rights reserved.

CLUES TO FLIGHT 990 DISASTER

LONDON, November 3, Graphic News: SPECULATION that an engine part Ð blamed in a previous fatal Boeing 767 crash Ð may have forced EgyptAir Flight 990 to Cairo to crash into the sea shortly after take-off from New York, killing all 217 people on board, is being questioned by aviation experts that have seen radar tapes of the planeÕs final moments. 
Accidental deployment of a thrust reverser would have caused the plane to turn as it began to descend. The tapes show Flight 990 diving in a straight line, at a speed of 690 mph, before turning to the right.
Lauda Air chairman Niki Lauda said on Wednesday it was highly unlikely that the crash could have been caused by a thrust reverser activating in flight if the Boeing 767-300 was operated correctly.
The former motor racing champion said modifications to thrust reversers Ð which slow an aircraft during landing Ð following a Lauda Air Boeing 767 crash in Thailand in 1991 had made them Òfailsafe.Ó
ÒWith the knowledge of the system, and assuming the plane was operated correctly, I can categorically rule out that the thrust reverser will deploy in flight,Õ he said.
Radar tapes from the New York air traffic control centre in Ronkonkoma show the EgyptAir flight at 33,000 feet (10,000 metres) before it began to plummet toward the ocean.
Tapes from other radar sites throughout the region Ð among them Nantucket, Massachusetts, and the Boston centre in Nashua, New Hampshire, where controllers who were not directing the flight observed the planeÕs plunge Ð indicate the plane was travelling at nearly supersonic speed and remained relatively intact before it shattered on impact with the ocean surface.
Investigators from the National Transportation Safety Board and the Federal Aviation Administration still donÕt know what happened, but the thought that an intact aircraft entered a sudden and fatal dive indicates the possibility that something happened to the crew.
ÒAn airplane just doesnÕt dive out of the air at that altitude unless thereÕs something that happens,Ó Billie Vincent, former security chief for the Federal Aviation Administration, said Tuesday.
The National Transportation Safety Board said the EgyptAir Boeing 767 was cruising at 33,000 feet (10,000 metres) when it suddenly descended in a straight line to 16,700 feet (5,100 metres) Ð a drop of 16,300 feet(4,900 metres) Ð within 40 seconds. At the time, the plane had a ground speed of about 600 knots, or about 690 mph (1,100kmh).
After the planeÕs transponder provided that last altitude reading, radar tracked it turning steadily to the right for more than 37 seconds before disappearing from the scope about 65 miles southeast of Nantucket, said NTSB Chairman Jim Hall.
The fragmented remains indicate the fuselage hit the Atlantic Ocean with tremendous force. Merchant Marine students who were the first on the scene said the impact site was strewn with personal effects and parts of the Boeing 767.
NTSB told relatives not to expect the recovery of any intact bodies, suggesting the bulk of the plane stayed together until contact with the ocean surface, experts said.
After the Lauda Air disaster, in which 223 people were killed, all Boeing 767, 757 and 737 aircraft were fitted with a synchronizer lock as a fourth system to prevent activation of the thrust reverser in flight.
ÒEvery operator was required to do this. I was told by Boeing that EgyptAir had carried out the same modification as all the rest,Ó Lauda said.
/ENDS
Sources: Reuters, Associated Press, Aviation Week