Washington -- If TWA Flight 800 was blown out of the skies by a terrorist bomb, investigators have a good shot at finding the evidence to prove it, experts said Thursday.

Along with recovering victims' bodies, collecting as much plane debris as possible is a priority. The wreckage can be painstakingly pieced together in a rough reconstruction of the shattered plane.

Investigators will look for tell-tale signs that an explosive was detonated aboard the aircraft, where it was located and what chemicals were used. Their methods have paid off in the past, including identification of the suitcase with the bomb that brought down Pan Am Flight 103 over Lockerbie, Scotland, in 1988.

Probers will be looking for evidence of a blast that took place inside the fuselage and splayed metal outward, according to Richard Stone, president of the International Society of Air Safety Investigators.

"You can determine what kind of catastrophic event took place that caused the structure to deform,'' Stone said. Probers will be looking for pieces of the TWA 747's cargo hold and pieces of luggage that might have contained a bomb. But the evidence might also be in the passenger cab in, particularly if a suicide terrorist had a strap-on bomb that eluded detection. Chemical by-products from the explosion or unexploded blasting material can be analyzed to determine the identity of the explosive. "Even if it's just a smudge [of residue], any explosive has constituents which are unique to that explosive,'' said Seymour Himmel, an aerospace consultant and NASA safety adviser.

Analytical methods that sort chemicals by size and mass are capable of identifying concentrations as small as a few parts per billion. While seawater and jet fuel can complicate detection, explosive residues cling to metal and do not tend to dissolve in water, one specialist said.

Pathologists also will be looking for slivers of metal or other shrapnel imbedded in the bodies of passengers who sat close to a blast's place of origin, Stone said. The bodies also will be examined for chemical residues linked to explosives.

The cockpit voice recorder, if recovered, also can provide clues. Investigators may be able to hear the sound of an explosion and even analyze the sound waves for hints on the power of the bomb, Stone said.

Despite such investigative methods, "a lot depends on luck, whether you pick up that right piece of metal,'' a federal explosives investigator said. The probe often takes longer than expected and is "a journey rather than going for the bull's- eye,'' he said.