Hundreds of people, including Prime Minister Stephen Harper and Newfoundland and Labrador Premier Danny Williams, are expected to crowd into a St. John's church Wednesday night to pay their respects to the lives lost in a helicopter crash last week.

A multi-faith prayer service will be held at the Roman Catholic Basilica of St. John the Baptist, in honour of the 17 people who died when a Cougar Helicopters aircraft crashed into the Atlantic Ocean on March 12, about 55 kilometres southeast of St. John's.

Only one person survived the crash, which happened minutes after the chopper's crew reported mechanical problems, which authorities believe is related to a drop in oil pressure in the aircraft's gearbox.

While hosted by the Roman Catholic archdiocese, the service is open to all, regardless of their beliefs.

A Sikorsky S-92 helicopter flown by Cougar Helicopters crashed last Thursday while it was ferrying crews to the White Rose and Hibernia oilfields. (Cougar Helicopters)

Fr. Paul Lundrigan, a Catholic priest who works in the Goulds area of the city and an organizer of the service, said people in the community want to come together.

"Everyone has a desire to show their feelings, their grief and to show their love and support to the families of those who were aboard the helicopter," said Lundrigan.

A memorial service will be held Wednesday night at the Basilica of St. John the Baptist, in downtown St. John's. (John Gushue/ CBC)

"I think this will provide them an opportunity ... to express what they're feeling, to offer their strength, their hope, and their support and their faith to the families that are left behind."

The helicopter crashed not long after it left a base near the St. John's airport, to carry 16 people to two platforms working at oilfields more than 300 kilometres from St. John's. The flights to the platforms have been suspended while Transportation Safety Board investigators search for answers.

Some answers could soon be forthcoming. On Tuesday, the TSB said they had recovered both the cockpit voice recorder and the flight data recorder, often called the black box, and had sent them to Ottawa for analysis.

The final bodies were recovered from the fuselage and delivered early Tuesday to the care of the chief medical examiner in St. John's.

Informal memorial grows

On Wednesday morning, TSB investigators aboard the offshore supply vessel Atlantic Osprey continued work on how best to raise the Sikorsky S-92 aircraft from the ocean floor. It is submerged under 178 metres of water, and crews have been using remote-operated vehicles in the effort.

First officer Tim Lanouette, left, and pilot Matt Davis reported mechanical problems in the final minutes of the Cougar Helicopters flight. (CBC)

An informal memorial that started spontaneously at the Cougar Helicopter base has continued to grow. For several days, mourners have been fixing bouquets of flowers to a chain link fence, just metres away from where the passengers boarded their last flight.

Mark Otfinowski, who regularly takes Cougar flights to his job on the Hibernia oil platform, visited the site on Monday. He said offshore life is more than just an industry.

"That's my family," said Otfinowski, who flew often with the pilot, Matthew Davis, and who knew some of the passengers.

"It's personal and devastating for each of us," he told CBC News. "There's a special selection of people and we are very close, ready to die helping each other, and I am one of them."

According to information released by the RCMP and published in obituaries, the deceased in the crash are:

• Thomas Anwyll, 46, Langley, B.C.
• Peter Breen, 55, St. John's.
• Gary Corbett, 46, Conception Bay South.
• Matthew William Thomas Davis, 34, St. John's, pilot of the helicopter.
• Wade Drake, 42, Fortune.
• Wade Duggan, 32, Witless Bay.
• Corey Eddy, 32, of Paradise, formerly of Sibley's Cove.
• Keith Escott, 39, St. John's.
• Colin Henley, 38, St. John's.
• Tim Lanouette, 48, Comox, B.C., first officer on the helicopter.
• Allison Maher, 26, Mount Pearl, formerly of Aquaforte.
• Ken MacRae, 47, Greenwood, N.S.
• Gregory Wayne Morris, 39, Outer Cove.
• Derrick Mullowney, 51, Bay Bulls.
• Burch Nash, 44, Fortune.
• John Pelley, 41, Deer Lake.
• Paul Pike, 49, Shearstown.