One year after the crash of Swissair flight 111 that killed all 229 people on board, the legacy of the tragedy is greater care for safety in the air.

The investigation into the crash of the passenger jet, although not yet complete, has already led to changes in airline safety.

Investigators have discovered that the plane caught fire as it flew from New York to Geneva. The pilots reported smoke in the cockpit just minutes before the plane crashed into the waters off Peggy's Cove, Nova Scotia.

Investigation's partial reconstruction of Swissair 111 jet
Investigation's partial reconstruction of Swissair 111 jet

In the course of the investigation officials have pointed out a couple possible contributing factors: wiring that chafes easily and flamable insulation.

Although nothing has been proved at this point, safety officials are already making preventative moves.

Boeing officials have defended kapton wiring, the kind used in the Swissair jet. Still, the Federal Aviation Administration has a committee looking at aging wiring.

Seven wiring inspections of MD-11 planes have also been ordered.

Aviation safety advocate Hans Ephromson-Abt says the focus on wiring is appropriate because there have been wiring fires before, just not with this level of fatality.

"Undoubtedly they knew what the weaknesses were but they never corrected them because they felt these things are isolated incidents," Ephromson-Abt says.

The FAA has also ordered the removal of the kind of insulation blankets used on flight 111, saying they're too flammable.

Chief investigator Vic Gerden is pleased with the changes but he says he'll be watching the aviation industry.

"We will monitor the specific followup as the weeks go on to see what indeed will change," Gerden says.

As the investigation continues, the Transportation Safety Board plans to dredge the ocean floor at the crash site. It hopes the key to solving the cause of the crash can be found in the tiny pieces of plane still at the bottom of the sea.