The date is 9 August 2006. Some five years after the tragic events of 9/11, a plot of comparable gravity was foiled, when 24 UK men were arrested in a night-time raid, charged with conspiring to blow up as many as ten transatlantic flights.
"We are confident we have disrupted a plan by terrorists to cause untold death and destruction," said Paul Stephenson, London police deputy commissioner at the time. "Put simply, this was intended to be mass murder on an unimaginable scale."
As was the case five years earlier, the airlines reacted swiftly. The attacks on the Twin Towers prompted the EU to tighten up aviation security, with each member state ushered under its regulatory umbrella. Now, in the wake of this latest threat, the rules became tighter still. Authorities turned their attention to the terrorists' attempted weapon - home-made explosive liquids carried on board in drinks bottles - and duly banned all liquids from aircraft hand luggage. By 6 November, this temporary ban had been replaced by a permanent embargo.
While liquids, aerosols and gels (LAGs) could be brought on flights, they needed to be in individual containers, no more than 100ml each in capacity and packed in a transparent, resealable plastic bag. This regulation has remained in place since.
From a security standpoint, the measure was unimpeachable: a quick-fire response to a newly minted threat. For the average passenger, however, it simply heightened the inconvenience of check in. It slowed down an already cumbersome process and sometimes entailed discarding expensive perfumes and liqueurs. Nor was there unequivocal approval among the EU governance.
"The liquids regulation was questioned by the EU parliament - they didn't like it," explains Johnnie Müller, head of security at Copenhagen Airport. "So, in 2010, new legislation was brought in, stating that the liquid rules would need to be changed."
This new framework, which came into force on 29 April 2010, superseded its post-9/11 equivalent and aimed to simplify procedures. Improvements were called for on all counts: enhancing the passenger experience, shortening airport transfer times and trimming unnecessary expenditure.
Counting the cost
The document also set out a timeline for the relaxation of the liquids rule. All LAGs, it stated, should be permitted in cabin baggage from April 2013, following a preliminary roll-out phase. This would mean installing screening equipment at every EU airport - X-ray machines that could reliably differentiate between harmless and explosive-laden liquids. While this might sound like a welcome development, progress in the interim has stalled. Possibly, the legislation overreached itself; Müller claims that the technology lags some way behind the regulations.
"The EU parliament says that, in 2013, everything will go back to how it was before 2006, that you can start travelling with liquids again," he explains. "But the reality is this won't happen because that equipment is not developed. The situation in 2013 will be much worse than it is today."
He is speaking from weary experience. Just last year, Copenhagen Airport was forced to make investments in preparation for a scheduled EU benchmark. The airport spent the money, the benchmark date passed, but the relevant rules failed to fall into place.
Such incidents lend ammunition to a widespread argument: the view that, since 2002, individual European airports have lacked sufficient control over their security spending. Tethered to layers of regulations - much of it the result of knee-jerk decisions - an airport's role in the proceedings might be seen as frustratingly limited.
Müller believes the liquid screening equipment will prove to be yet another unnecessary expenditure.
"If we have to invest in X-rays that involve presenting the liquids separately, it will decrease the cost-efficiency and the process speed," he says. "We will have to recruit hundreds of new security employees just to adapt. So, we find this type of investment ridiculous. It doesn't add anything; it's just a waste of money."
His preferred option would be to stick with the existing regime for now, and wait for the technology to arrive at a more cost-effective juncture. Within a few years, there will be devices that allow liquids to be scanned without removing them from the bag.
Of course, Copenhagen does not answer just to the EU, but also to national guidelines. The airport must pay heed to the Danish Air Navigation Act, along with a threat evaluation from the Secret Service.
The Danish Civil Aviation Administration (CAA-DK) is responsible for monitoring compliance on every side. Within these, admittedly stringent, constraints, the airport does have full leeway to optimise its security budget.
Broadly, there is a trade-off to be had between two critical factors: minimising inconvenience for the passenger, while keeping security at the top of its game. This balancing act makes passenger security a far tougher challenge than cargo, which, says Müller, is a "fixed process" and fairly straightforward for all concerned. Fortunately for the passenger, no airport can afford to shy away from complexity.
"In Copenhagen, we will invest immediately in technology if it increases security and productivity, and improves the passenger experience," says Müller. "We have spent a lot of time and money creating a calm, quiet security area. We want to give a very relaxed, yet efficient, experience."
Passenger comfort is one of the principal drivers behind the airport's latest big investment. By 2014, after rebuilding and enhancing its security areas, Copenhagen expects to have full-body scanners installed. While such scanners have been controversial since the outset, largely due to concerns about privacy and radiation, supporters say that they are far less intrusive than the existing system of physical pat-downs.
"We are trying to test some body scanners very silently, working with other airports, and all the different security departments, to test different equipment and discuss the outcome," says Müller.
Looking to the future, Müller advises that security technology should neither remain static, nor be overly bound by EU targets that specify set dates for its development. Terrorists being as inventive as they are, an airport needs the capacity to adapt its strategy quickly. It needs the flexibility to respond to every eventuality, without the additional burden of extra rules.
At present, Copenhagen Airport is working to develop a new security concept. This is based on the PreCheck pilot programme in the US, a push by the Obama administration towards a risk-based security model. The idea is that, through vetting passengers in advance, high-risk individuals will be subjected to greater checks than, say, a law-abiding frequent flier. The low-risk individuals will be fast-tracked through.
Müller thinks that passenger profiling is also the way forward in Europe.
His airport is working hard to convince the EU of its merits, and why it should abandon the present one-size-fits-all approach.
In the meantime, Copenhagen is doing what it can to stay abreast of the legislation, working with it and around it while concentrating on the challenges closer to home.
"Instead of just following the regime, we will try to automate a lot of tasks," says Müller. "We can then spend more time on specific airport-related security where we find that the education of our staff is better used. That will be our strategy for the future."