Preparing for T5

31 March 2008 (Last Updated March 31st, 2008 18:30)

Airport Technology takes a look at the technology of Heathrow T5 that is hoped to help it live up to expectations. By Dr Gareth Evans.

Preparing for T5

Heathrow's new terminal 5 stands as one of the biggest construction projects ever to be attempted in the UK, while also claiming the additional – and somewhat rare – accolade of being delivered on time and within budget.

Although the original design competition was won in 1988 – two years after terminal 4 had opened by Rogers Stirk Harbour and Partners (then Richard Rogers Partnership) – the ensuing controversy and the longest public enquiry in British planning history delayed work until late 2002.

"Heathrow's new terminal 5 stands as one of the biggest construction projects ever to be attempted in the UK."

In the end, the design, construction process, project management and use of technology surrounding the T5 development has come to reflect the advances of those intervening years and should prove pivotal in ensuring Heathrow's ongoing importance in 21st century aviation.

T5 TECHNOLOGY

Nowhere is this more obvious than in the project's comprehensive use of technology to address everything from ticketing to environmental issues.

According to Nick Gaines, director of business critical systems for airport company BAA, technology is ubiquitous within T5 making it what he describes as 'a fully integrated and IP-delivered building-managed environment, a truly networked building'.

The scope of this achievement is considerable, since within a site roughly the size of London's Hyde Park, there are over 2,100 PCs, 5,000 mobile phones and PDAs, 9,000 connected devices, more than 160 systems and nearly 550 interfaces. Technology has also been used to achieve the stated goal of easing the flow of passengers – from active RFID tags in the taxis and embedded sensors to detect traffic flow to the world's first personal rapid transit (PRT) system.

The 20-year-plus history of T5 has enabled the design environment to flex and evolve as the demands of the business itself have changed – and, equally, permit progressive flexibility to be built in to allow for further developments in the future.

This thinking has allowed a holistic approach to be taken from the outset, building the technological response to unite the varied aspects of a busy airport operation into a cohesive unit, rather than attempting to select individual system benefits in isolation. Instead of having to build business processes and systems to match an existing building, T5 has offered unparalleled opportunities to BAA and BA (the sole user of the new terminal) for project-integral design, allowing processes to dictate facility functionality, which in turn defines the way systems will work.

"The original Heathrow T5 design competition was won in 1988 – two years after terminal 4."

With aviation so often put under the 'green' microscope, BAA has met many of the environmental concerns surrounding the operation of the terminal head on, using a variety of technologies to offset and mitigate its impact. Waste heat from a combined heat and power plant will provide more than 80% of the terminal's heat – avoiding an estimated 11,000t of CO2 annually – while to cool the building, water from zero-carbon-rated ammonia chillers will be circulated, as required.

Lighting is carefully controlled and conveyor systems have variable speed drives to reduce energy consumption during periods of low-demand, while rainwater harvesting and borehole extraction meet 70% of the water needs to avoid placing undue strain on the mains. Water saving is also a major feature, with low flush volume toilets, automatic on/off sensors and aerated flow shower heads being standard.

Integration is another major factor in the technology usage. While T5 may enjoy the luxury of newly purpose made systems, they still need to be compatible with those pre-existing at Heathrow, not least to ensure baggage tracking and security applications run correctly. This called for a series of changes to around 70 of the older systems to integrate the new.

While backwards compatibility is an obvious necessity, the value of attempts to future-proof has not been overlooked in the process. Check-in kiosks have been designed to allow passengers to be photographed, should such a requirement come into force, and allowance has been made to accommodate biometric recognition technology if required in years to come.

DESIGN SUCCESS

As the first step in BAA's plan to upgrade and modernise the whole of Heathrow – and serve up to 35 million passengers a year – the development has deliberately been designed to redefine the entire user experience.

"The 20-year-plus history of T5 has enabled the design environment to flex and evolve."

The difference of approach is apparent even before the traveller enters the terminal building, with a pedestrian zone – the interchange plaza – offering a clear 30m of space spanned by four glazed bridges, the abundant natural light emphasising the overall feeling of open airiness.

Once inside, passengers find themselves in an environment which has been specifically laid out to continue the theme of maximised user-friendliness.

Since studies into passenger behaviour at UK airports have consistently revealed that stress-levels are at their highest during check-in, the design features a large main hall, creating an openness which both revolutionises the general ambience and helps lower feelings of anxiety. In the same vein, screening areas have also been designed to be as open as possible, within the inevitable constraints of modern-day security.

At the same time, the design concept has also embraced T5 as both the primary entry point for London – and the UK – and a major showcase for the flag carrier, with BA transferring its operations from the other terminals to become the sole occupier. In addition, as London gears up to host the 2012 Olympic Games – the opportunity to grandstand what Alan Lamond, aviation director for T5 production architect Pascall & Watson, describes as 'a spectacular piece of architecture and engineering' is clear.

T5 CONSTRUCTION PROCESS

As the world's busiest international airport, it was clear from the outset that the construction work for T5 could not be allowed to impact on Heathrow's normal operation, which inevitably posed some major challenges for the contractors.

"BAA has met many of the environmental concerns surrounding the operation of T5 head on."

The project called for around 13.5km of tunnel – roughly the equivalent of a third of the underwater section of the Channel Tunnel – to be bored with a significant amount of this needing to be created beneath the 'live' airfield and close to pre-existing rail tunnels.

Planning and careful 3D monitoring in real-time were essential to ensure the necessary tunnelling was accomplished successfully.

Above ground, there were other constraints, including an imposed height limit on cranes, to avoid the possibility of disrupting airport radar, which led to the main sections of the roof along with some of the beams having to be jacked – rather than lifted – into position.

The use of off-site testing has led to a number of time savings and cost reductions being made possible during the construction process, perhaps most significantly in terms of the roof and main terminal façade, which were pre-constructed. This enabled tolerance and sequencing issues to be ironed out ahead of final assembly – and the lessons drawn from this experience were subsequently applied to the construction and fit-out of the T5 bays.

Since in-situ concrete was used to create most of the development, effective use of digital dimensional information was essential to ensure the accuracy of casting patterns for the project – typically working to tolerances of 1mm or less. The ability to produce castings at this level of accuracy using lasers / water jets has demonstrated the efficacy and importance of the technology, while allowing greater product quality control to be achieved along with minimal wastage.

As a result, rapid prototyping was also facilitated, leading to much faster problem solving options being available to the design team, when required.

PROJECT MANAGEMENT

Successfully completing a project of this magnitude called for a wide range of engineering and other disciplines and with over 60 contractors, 16 major projects and nearly 150 sub-projects underway on the 260 hectare site, a unique management approach was called for.

"Construction work for T5 could not be allowed to impact on Heathrow's normal operation."

By accepting the risk for the construction, as well as being responsible for funding it, BAA released the contractors from fears of penalties and blame for any delays, and enabled them to concentrate entirely on delivering the project.

In addition, the 'project flow' software system was used to collate and control raw material demand, ensuring they arrived on a just-in-time basis, while to reduce the impact of the construction work, two local consolidation centres were created to provide storage.

Despite its position as the world's busiest airport, Heathrow is not immune to overseas competition and with its two runways operating at near-capacity, rival European airports are an ever-present business threat. Already Amsterdam and Paris serve more regional airports in the UK than Heathrow.

This new terminal, with over 112 prestige outlets set to open – including Harrods, Coach, Prada, Paul Smith, Ted Baker and Reiss – should boost Heathrow's overall image and help see off the foreign challenge, at least for the foreseeable future.