Sixteen men on board the AS332-L2 helicopter were killed when the aircraft suffered a catastrophic gearbox failure on April 1, 2009.
The two crew and 14 oil workers were on their way home from the BP Miller platform when the chopper fell out of the sky into the sea.
No-one survived the tragedy.
The Air Accident Investigation Branch launched an investigation to establish what caused the disaster and published a report on its findings in November 2011.
Last year the Crown Office ruled that no criminal proceedings would be taken due to insufficient evidence.
‘Near five-year delay’
It was decided that a fatal accident inquiry would be held at the Town House in Aberdeen which started on January 6.
Yesterday Tom Marshall, the lawyer representing the families, criticised the length of time it had taken for the inquiry to be held.
He said: “The near five year delay has been prejudicial to the inquiry.
“This delay is entirely unacceptable.”
Mr Marshall told the inquiry that the recollection of witnesses giving evidence at the Super Puma inquiry had been impaired because of the delay.
He added that the families only had four months to prepare for the inquiry, which made it “unneccesarily difficult”.
Mr Marshall said a fatal accident inquiry into the Lockerbie Pan Am Flight 103 bombing was held before the third anniversary of the disaster.
Depute fiscal Geoff Main told the inquiry that the Air Accident Investigation Branch investigation took precedence over everything else.
He said police and the prosecution service then liaised with the AAIB and considered whether any criminal action would be taken.
After the hearing yesterday, Audrey Wood, who lost son Stuart, 27, in the tragedy, spoke on behalf of the families.
Mrs Wood, of Newmachar in Aberdeenshire, said: “This has been the most horrific, traumatic five years of strung out emotional upsets for all 16 families and friends.
“It has been a perpetual rollercoaster of which we could not get off.
“And of course, the length of time this case had taken to get to court has prolonged the grieving process.
“We do hope we can all find some peace in years to come.
“It’s been a very tough six weeks but we needed to hear the evidence and the lead up to the tragic event.”
She added: “We can only hope that accountability and responsibility will be addressed, and await the sheriff’s determination.
“Sixteen lives were lost and left many families broken hearted. Their memories will live on forever.”
Proper procedures ‘not carried out’
Final submissions from lawyers representing all parties involved were submitted to Sheriff Derek Pyle at the hearing yesterday.
Witnesses from the AAIB, helicopter manufacturer Eurocopter and the aircraft operator Bond have given evidence over the past few weeks.
The inquiry heard that proper procedures were not carried out when problems with the chopper were discovered on March 25, a few days before the crash.
Bond engineers told Eurocopter specialists that there were problems with the flight safety system on the phone.
The manufacturers were also informed of the discovery of a particle on a helicopter part.
The information should have been written down on a special form and sent to Eurocopter team rather than by phone.
Two chip detectors were installed in the AS332-L2 helicopters.
Eurocopter staff believed the particle had been uncovered in the main gearbox and instructed Bond engineers to follow the instructions of a work card.
But the chip had actually been detected in the epicyclic module and the inquiry heard the aircraft maintenance manual should have been used to deal with the problem instead.
The helicopter was eventually deemed safe to fly and crashed after a planet gear in the epicyclic module cracked a few days later.
Mr Marshall yesterday claimed the accident would not have happened if proper maintenance procedures been followed because the gearbox would have been removed.
Eurocopter lawyer Murdo MacLeod QC said there was a “clear and compelling” case pointing towards the gear failure being caused by spalling.
Spalling can be caused by two pieces of metal rubbing together which can cause a crack resulting in particles of metal falling off a component.
The inquiry heard that the particle identified in the epicyclic chip detector could have been as a result of the planet gear spalling.
Sheriff Derek Pyle said there did not appear to be anything other than maintenance procedures which could be relied upon to avoid helicopters falling into the sea with catastrophic consequences.
He added that there was no hint of any fundamental change or approach by the industry by way of manufacturing to change this.
The sheriff said he expected his determination to be available in about four weeks.