Security measures for flights inbound to America stepped up a gear following the attempted attack on a plane heading for the US on Christmas Day.
How then was I was able to unwittingly carry a 200ml hairspray can - twice the liquid limit - onto a Qantas flight to the US, after two separate supposedly rigorous security checks?
Let me make it clear, there was no intention to flout the rules. It wasn't an attempt to test the rigour of the new security. It was a mistake on my part to put the aerosol can in my hand luggage.
It wasn't until I boarded the flight and opened the bag to search for a book that I discovered the large aerosol tin at the bottom of my bag.
So why wasn't it spotted?
My cabin bag was first scanned after I checked in at Sydney's Kingsford Smith Airport for the QF107 flight to LA and New York on Monday morning.
In common with every flight at every airport, as I walked to departures the hand luggage was X-rayed along with my coat and camera bag, while I walked through a scanner.
No one spotted the spray can at that point. Had I known it was there I would have handed it in.
Just over an hour after that first security check the departure gate opened. Passengers on my flight were asked to arrive at the gate early, to undergo that second tier of enhanced security now required by the US authorities.
A security officer removed my purse and make-up bag for inspection and he looked at my camera.
There is heightened security for those travelling to and around America
As he looked in my bag I was being "patted down" by a female officer - I was also asked to remove my shoes, which were examined, but the pair of boots I had put in the bag to wear in New York were not.
The whole search took around 90 seconds, yet once again the spray was missed.
Once on board there was another change - again the result of the new security brought in by the attempted attack.
The captain made an announcement informing us that the US regulations meant we wouldn't be allowed to congregate in groups during the flight and passengers were not to gather around the toilet area.
But the stricter rules forbidding passengers to go to the toilet or to have blankets or pillows on their laps during the final hour of the flight had been relaxed.
One flight attendant told me it was an almost impossible rule to police.
One thing that was notably different was the lack of easy familiarity with the cabin staff. They seemed more edgy and alert to noise or people moving around the cabin.
A group of young men sitting behind me had hoped to take advantage of the free alcohol served throughout the long flight, but they were told by staff that the authorities "wouldn't be happy if they continued".
Halfway into the flight to LA, a passenger took a photograph and the icy blue flash from the camera bounced momentarily across the dimly lit cabin.
Issues such as this are extremely rare and they are taken seriously
The anxious stares of near neighbours and the swift arrival of a flight attendant illustrated all too clearly the concerns felt by those travelling to a nation targeted by terrorists - for whom the plane is the weapon of choice.
Most seemed resigned to the latest constraints. One middle-aged woman appeared confused by the long queue of people at the departure gate waiting for the second level search.
When I explained why we were waiting she threw her hands in a gesture of defeat. "Whatever it takes to keep us safe, honey."
In response, Sydney Airport said it "successfully screens millions of passengers each year" and that "issues such as this are extremely rare and they are taken seriously".
It added: "The carriage of a 200ml aerosol, instead of the allowable 100ml aerosol, onto an aircraft that you have reported is being reviewed by Sydney Airport which undertakes the primary screening.
"We have also informed Qantas as the airline undertakes the secondary screening for its flights to the USA. Qantas has indicated that it is investigating.
"The matter has also been reported to the Australian Government's Office of Transport Security."
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