For the passengers who arrived in Abu Dhabi on a flight on July 15, there was only relief at their early arrival after a tedious 14-hours in the air.
It would be another two weeks before they learned that someone had apparently tried to stow a bomb on board.
There had been no security failure. An unwitting dupe, the brother of one of the alleged plotters, never made it past check-in with the luggage, let alone security.
Investigators believe that the bomb, disguised as a meat mincer, was either too heavy to have been stowed on board the Etihad flight, or the would-be terrorists had second thoughts.
But despite the abject failure of the apparent plot, it exposed major weaknesses in the global airport security regime that has been repeatedly exploited by terrorists, experts said Wednesday.
The ISIL-inspired and directed plot started with high-grade military explosives being flown undetected inside air freight from Turkey to Australia and then turned into a viable bomb at a property in a Sydney suburb, officials said.
Prosecutors believe that a senior commander based in Syria directed the bomb-making before the aborted attempt to put it on the plane. One of the alleged plotters then left the airport with the bag.
Sydney bomb plot
The incident highlighted how improved airport security equipment have forced terrorists to deploy increasingly imaginative methods to smuggle explosives on board planes. But it also showed how cargo flights have proven to be the “soft underbelly” of airport security and militants have targeted less-regulated airports and cargo depots to move explosives around the world.
The Australian authorities said the failure to spot the explosives en route from Turkey to Australia was a “troubling” security breach.
"All the security agencies and those responsible for security of cargo …have put in place extra measures since that time," said Australian Federal Police Deputy Commissioner National Security Michael Phelan. "It is a concern that it got through, yes, it's hard to deny that."
A 2007 report by the left-leaning thinktank, the Center for American Progress, found that the US authorities were spending ten times more on checking passenger luggage than the cargo that could travel on the same plane. Cargo flights have been less scrutinised based in part on the assumption that terrorists were focused on inflicting mass casualty attacks on passenger jets.
“The big slip-up was with the stuff getting on the plane to Australia,” said Raffaello Pantucci, director of international security studies at the Royal United Services Institute thinktank. “Cargo planes have been a problem for a long time.”
The apparent failure of the Australian terror attack follows the uncovering of a plot in 2010 using explosives hidden inside computer printers and stowed on two cargo planes bound from Yemen to the United States.
Saudi Arabia provided intelligence which led to the discovery in 2010 of the devices during stopovers in Dubai and the UK.
The explosives found in Dubai had been carried by two passenger planes before they arrived in Dubai. They were believed to be timed to explode over US cities, with Al Qaeda in the Arabian Peninsula claiming responsibility for the plot.
Mr Pantucci said that the failure to identify the printer bombs in Sana’a showed that security was only as strong as the weakest link in the globalised network of air travel.
Turkey has sought to play down any security failure over the transport of the material for the alleged Etihad bomb and has questioned Australian claims about the source of the material.
The two countries have started work “to clarify unclear and unconfirmed matters regarding the possibility that explosive substances were sent from Turkey three months ago,” according to a weekend statement reported by Turkish media.
In light of the plot, the Australian authorities are reportedly considering tightening passenger measures including the re-introduction of limits on bringing gels and liquids on board planes and full-body scans.
The enhanced measures would have been unlikely to have had any impact in Etihad flight as the luggage did not reach the security desks before it was taken out of the airport. Tests after the uncovering of the plot suggested that the bomb would not have got through security screening, said officials.
The brother boarded the flight but it is not known if he remains in Abu Dhabi, or continued to another destination from the hub airport. He has not returned to Australia, said officials last week.
Authorities say they do not believe he was involved in the plot, suggesting that he has been interviewed or that they have secured communications’ evidence that pointed to him being kept in the dark.
Following the failure of the aircraft bomb plot, the device was dismantled and the plotters allegedly discussed with their ISIL handler how to build a device to release poisonous gas in a public area, officials said. They had gathered chemicals but the gas bomb was far from being a viable device.
No target was identified but a gathering place of transport hub appears to have been uppermost in their nascent plans, according to the intercepted communications.
The apparent shift in focus from blowing up an airliner to seeking mass casualties in a poison gas attack follows a pattern of changing ISIL tactics posing new challenges to governments and security officials, according to officials.
It followed coordinated triple-suicide bomb attacks claimed by ISIL on a crowded departures hall at Brussels airport in March 2016 and a metro station that left 32 people dead and another 300 wounded.
CCTV footage showed three of the plotters pushing suitcases on trollies that were believed to have contained the explosives.
“They see airports as part of the national infrastructure and a target, which just happens to have aircraft there,” said Tom Hardiman, an aviation security consultant for the London-based Egremont Group.
“That requires a broader view of the security measures needed - and that’s when it’s complicated working out what you can and can’t do using policing and domestic laws in a land-side area”
The Etihad plot only came to light after the flight completed its journey without incident. Foreign intelligence agencies – reportedly the UK and US – alerted their counterparts in Australia on July 26 to the discussions about the gas attack between the Syria-based commander and the Sydney based operatives.
The plot – described as one of the most sophisticated terrorist plots ever attempted on Australian soil - led to raids in Australia three days later and the arrests of four men.
Two of them, identified by domestic media as Khaled Khayat and Mahmoud Khayat, were each charged with two counts of planning a terrorist act. The charges carry a maximum punishment of life in prison. Two others have been released.
Full details of the attack planning have yet to emerge. The two men did not apply for bail after a brief court hearing last week, and are next due in court in November. Their lawyer said the pair were “entitled to the presumption of innocence.”
One of the four released on Sunday, Khaled Merhi, said that he knew nothing about the plot. "Zilch mate, nothing, I had no idea," he told The Daily Telegraph.
It was only after the arrests on the weekend of June 29 that passengers became aware that they were potential targets.
One woman, Colleen Daniels, only realised what had happened after arriving in Russia for lifesaving multiple sclerosis treatment. He family had spent years saving money for the procedure.
“It could have all been lost in the air somewhere, which certainly makes you put your life into perspective,” her husband Kel, a former police worker who also travelled to Russia, told The Australian.
“We’re not armour-plated or bullet proof, we’re all vulnerable, whether it be on a plane or just walking down the street.”