Families gathered near Peggy's Cove, Nova Scotia Monday to pray and remember love ones who died four years ago in the crash of Swissair Flight 111.

Flight 111 plunged into St. Margarets Bay on the stormy night of September 2, 1998, breaking into about two million pieces, and killing all 229 people on board.

Fishermen and rescue workers spent 36 hours searching for survivors after the crash -- but only succeeded in finding body parts. Many of the recovery workers continue to suffer from post-traumatic stress disorder.

The cause of the crash has never been precisely pinpointed. It's known that the pilot on the New York-to-Geneva flight radioed he had smoke in the cockpit, and was trying to make an emergency landing in Halifax. The MD-11 jet was dumping fuel over the Atlantic Ocean when it suddenly went down and crashed.

The Transportation Safety Board has completed its investigation, but won't be releasing its final report until next year.

The draft report has been released to investigators. Citing confidentiality, however, the board has refused to allow family members of those who died to access the report.

"I just want to know," says Barb Hausman, who lost her sister in the crash. "I want to read it, and I want to know exactly what it was that brought it down."

Reserve Army Chaplain John O'Donnell, who assisted family members at the site four years ago, says keeping the findings from relatives denies them their right to closure.

"They don't want to hear about it from the media. They have a right to know."

Investigators have determined there was a fire in the ceiling at the front of the plane but haven't made public what caused the fire. Wiring and insulation in the cockpit have been blamed in initial reports.

Burnt pieces of both the plane's general purpose wiring and wires leading to a controversial in-flight entertainment system were found in the wreckage. The entertainment system was later banned by the U.S. Federal Aviation Administration.

In 1999, after investigators determined that metallized Mylar insulation on the plane helped to spread the fire, the FAA ordered U.S.-registered airlines to replace the material within four years.

TSB spokesman Jim Harris has said that given the nature of the crash, the length of the investigation isn't unusual. He notes that it took recovery crews almost 15 months to bring the wreckage up from the ocean floor. Crews eventually salvaged 98 per cent of the aircraft by weight.

And Harris points out that the flight recorders stopped six minutes before impact, which made the investigation much more difficult.

While Harris couldn't say if investigators have come to a conclusion about wiring's role in the disaster, he said it's unlikely just one culprit will be named as the cause.

The recovery operation and crash probe have cost $54.8 million.