THE parents of a man killed in the Clutha pub helicopter disaster want to know why a fatal accident inquiry still has not been held into the tragedy while a similar investigation into the fatal Glasgow bin lorry crash was able to get underway so quickly.

Ian and Mona O’Prey say that when they heard an FAI was being held into the Glasgow bin lorry crash just seven months after the city centre tragedy which killed six people, they feared they had been forgotten.

Their son Mark, 44, was one of 10 people to die after a Police Scotland helicopter fell through the roof of the Clutha pub in Glasgow nearly two years ago.

But the grandparents from East Kilbride, South Lanarkshire, still have no idea when an inquiry will happen or if criminal proceedings will be held into the crash.

They still don’t know how or why their son – a dad-of-one to Liam, now 16 - died.

As they prepare to scatter Mark’s ashes on August 14, the day he would have turned 46, the family have called for answers.

An interim report by the Air Accident Investigation Branch (AAIB) in April 2014 found that both engines in the aircraft had failed, but did not set out the cause.

A full report into the technical cause was due to be published “in the middle of 2015” but to date there is no sign of it.

The Crown Office said it was waiting for the report and could not move forward with other investigations until it had the findings.

Ian O’Prey, 69, has arranged a meeting with the First Minister in a bid to speed up the process. He met Nicola Sturgeon at the re-opening of the Clutha bar, in the Glasgow city centre’s Stockwell Street, last month.

Sturgeon raised concerns about the length of time the AAIB investigation was taking through a letter to David Cameron in February.

Ian O'Prey said: “What else can I do? I spoke to Nicola Sturgeon when I was there. I asked her: ‘Can you find out anything out for me?’ So I have to go and meet her on the 29th of this month through in Edinburgh.

“That’s the best I can do - go to the top of the tree and see if she can find out anything for us.”

The couple feel they are being left out of the loop. Their upset is compounded by the speed at which the FAI into another city centre tragedy – the bin lorry crash which killed six people just before Christmas – got underway.

The crash happened on December 22 and an FAI, which started on July 22, is currently on-going at Glasgow Sheriff Court.

Mona O’Prey, 72, said: “I was quite surprised that the bin lorry inquiry happened so fast. Immediately there was an FAI for that. I don’t know anything about these things. But I said to him (her husband Ian): ‘There’s an FAI about that bin lorry and they hadn’t even thought about an FAI (with the Clutha)’ and I thought that was a bit much. I suppose we’re in the hands of these people that run all these things.”

Her husband, Ian, a construction worker, is also concerned about how long it took to remove his son’s body from the pub.

The Clutha helicopter crash happened on Friday, November 29, 2013 at about 10.20pm and his body was removed three days later.

He said: “My main point is the length of time that they spent bringing the people out the building

“I thought it was just totally amateurish ... they didn’t even bring a crane.

“At the time I said: ‘Why has this helicopter not been suspended by crane?’ It was visibility sinking.

“They were saying it was dangerous, they can’t take it out. The helicopter became more important than the bodies.

“From half past 10 on Friday night to half past 10 on Monday morning – that’s just preposterous.”

The family want to know exactly when Mark died.

Mark, a music-loving window cleaner, was watching the Ska group Esperanza, in the Clutha.

“I asked them what time he died and they said the paramedic didn’t have a watch on,” his father said.

“It’s been total shut down. They’re not allowed to speak to us, they’re not allowed to talk about it. We don’t know.

“I’d love to have an FAI and ask why it took them so damn long to handle the operation.”

His wife said she feared an inquiry would never take place.

She said: “I don’t think they’ll ever do it now. It’s just been so long.

“I have no idea what happened to Mark. We were told we’d be able to read all these reports once they’d collated them all but this has never happened."

A spokesman from the AAIB said they could not reveal the publication date.

The spokesman said: "The Clutha investigation continues to ensure the AAIB are satisfied all evidence has been fully considered. The report is now being reviewed and will be published in due course."

They said victims’ families would receive the final report first.

A Crown spokesman said: "The Crown awaits the publication of the safety investigation report by the AAIB into the technical cause of the crash.

"It is essential [for the Crown] to have the AAIB's findings before the parallel investigation by Police Scotland, working with the assistance of the Civil Aviation Authority and under direction of the Crown, can be fully progressed in order that a decision may be taken as to the form of any proceedings that will take place."

A Scottish Government spokesman said the findings should be published “as soon as is possible”.

He said: “The First Minister has written to the Prime Minister on a number of occasions requesting information from AAIB is shared with those affected by the terrible accident at the Clutha Bar 21 months ago.

“It is important that the AAIB report is published as soon as is possible, to allow the necessary follow up investigations to be undertaken and so decisions can be reached about criminal proceedings and a Fatal Accident Inquiry.”

The crash claimed the lives of David Traill, pilot of the Eurocopter EC 135, and police constables Tony Collins and Kirsty Nelis, who were on board.

Along with Mark O'Prey, John McGarrigle, Gary Arthur, Colin Gibson, Robert Jenkins, and Samuel McGhee were killed in the pub. Joe Cusker was pulled from the wreckage alive but later died in hospital.

Bond Air Services did not want to comment.