NEW YORK — After two months and a series of unexpected setbacks, officials investigating the crash of Trans World Airlines Flight 800 have begun discussing what to tell the public should they fail to determine why the jumbo jet exploded over the ocean off Long Island.
The preliminary discussions come as rescue workers have retrieved about 80% of the wreckage, none of which has revealed whether the plane was downed by a bomb, a missile or mechanical failure.
Should there still be no determination of the cause after remaining debris is recovered--expected by this fall--and other steps are taken, officials are considering several options for what they would tell the public. These range from an interim report on the crash to admitting that they are temporarily stymied.
"We've talked generally on some of these issues," FBI Assistant Director James K. Kallstrom acknowledged in an interview Tuesday. "But we haven't crystallized our response yet. I don't know exactly what we would say or who would say what. We haven't put any words on paper yet."
While officials continue to vow that they will find the cause of the crash, this new planning contrasts with the public assurances issued by investigators and reveals a reality that is far less optimistic.
Only five of the crashes involving 350 large commercial American planes since 1967 have remained unsolved. Those for which causes have been determined include the tragedy most similar to the TWA catastrophe, the 1988 Pan American Airways Flight 103 disaster over Lockerbie, Scotland. But it is now clear that the TWA tragedy--a night crash over water--poses problems far thornier than most other crashes.
Kallstrom and other federal officials continue to show confidence in public that they will determine the cause of the July 17 tragedy, a position bolstered not only by statistics but by numerous outside experts who caution that--because this is such a complicated case--the inquiry must be allowed to run its course.
"They've just got to keep looking," said Walter Korsgaard, a former explosives expert for the Federal Aviation Administration who helped investigate the Lockerbie disaster.
With federal officials now hoping that the remaining 20% of the wreckage holds the key to the cause of the crash, they also are moving on several other fronts to further focus their inquiry.
Those strategies include reexamining the thousands of pieces of the plane already gathered in a Calverton, N.Y., hangar, dredging the ocean floor for any parts still lost and flying in an identical 747 jetliner for close-up comparison.
"These are the kinds of things that are being considered," said Robert Francis, vice chairman of the National Transportation Safety Board.
By looking again at each of the literally thousands of pieces of the aircraft that have been recovered, safety experts and law enforcement officials hope to find clues that may have been missed earlier. This could be a tedious process, they said, but could provide valuable new information as the doomed jet is reconstructed.
Investigators are taking preliminary steps to further refine their search and possibly comb the ocean floor for the smallest shards of wreckage. They have contacted private companies and have gotten estimates of the time and cost of dredging the two areas of major debris.
Estimates are that dredging could take as long as six weeks in the two major areas where most of the wreckage has been found at a rough cost of $2 million. The NTSB and FBI also are studying the possibility of vacuuming smaller selected areas.
In describing their joint investigation, Kallstrom and Francis often compare it to putting together a giant jigsaw puzzle from often tangled and sometimes difficult-to-identify pieces. An identical Boeing 747 would help in this process and provide a finished puzzle picture as a guide, providing a far better model than blueprints of the plane.
For the moment, however, these alternatives are only possibilities as divers concentrate on recovering the remaining pieces of the doomed flight. Estimates are that it will take 17 to 21 days of diving to finish this task.
"The team's feeling is the critical-mass piece is still down there," said Kallstrom. But concurrent plans are underway, he said, because "you don't put your eggs in one basket in this business."
Officials think that the initial explosion, which led to the deaths of all 230 people aboard, took place in the center part of the airplane. Kallstrom said that only 20% to 25% of the center of the plane has been recovered so far.
Among the key items still missing is 40% of the center fuel tank and the tank's third fuel pump.
The FAA is considering whether to issue orders requiring "repetitive visual inspections" of the fuel pumps on Boeing 747 and series 757 airplanes after receiving several reports of leaking fuel pumps and moisture in the pumps that can cause corrosion of wires. Such corrosion can lead to electrical arcing and fires, the FAA noted.