Maintaining Manchester

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Martyn Cartledge spent a night with the team resurfacing one of Manchester Airport’s two runways.

The ADM and the PMO both make runway checks when work has been completed to ensure it is safe for aircraft operations. (All images via author)

It’s the early hours, it’s raining and I’m standing on a windswept building site… and I’m beginning to wonder why.  However, this is no ordinary building site, it is the main runway at a major international airport and currently it is full of holes and machinery, with flights inbound in just a few hours.

 

Essential repairs

There have been several batches of works on Manchester Airport’s (IATA – MAN) runway in the past, from re-grooving the asphalt to lessening the famous ‘hump’ in the middle (it is still not possible to see from one end of the runway to the other).

However, over time everything degrades.  Water seeps into places it shouldn’t and corrodes the wiring; drainage systems don’t work as well as they used to; and the lighting systems begin to need more than a spruce-up; not to mention the runway surface, which although it gets regular maintenance, eventually requires complete renewal.  So, as the existing approach and runway lighting system in the airport’s principal runway (05L/23R – Runway 1) was more than 30 years old, and reaching the end of its design life, the Manchester Airports Group (MAG) decided it needed to be replaced entirely to ensure continued safe and efficient operations.  So it made good sense to complete other works that were also on the horizon.  A programme was designed to not only replace the ‘skin’ of the runway but all its major organs, arteries and blood vessels as well, often using cutting-edge technology and equipment rarely seen in the UK or even the world.

One of the critical components in the decision to go ahead with such a massive and costly programme was the opening of the second runway (23L/05R – Runway 2) in February 2001, because CAA requirements dictate that no aircraft movements can take place when major works are being carried out on or adjacent to a runway.  Consequently, by using R2 (which is normally closed overnight) MAN could continue to operate a normal service.

It was decided to work during the quieter overnight period, because while R1 can accommodate around 55 movements per hour when used in single operating mode, R2 can manage just over 20.  So between January and August 2011, R1 05L/23R was closed to all traffic between 21:30 and 06:00, from Sunday to Thursday nights inclusively.

 

Challenges

The use of R2 brought considerable operational challenges.  In contrast to the UK’s other major airports, such as Heathrow and Gatwick, Manchester remains fully open each night of the year.  So the work had to be undertaken while normal flight operations continued.  In particular, the layout of the runways at Manchester means all aircraft going to and from R2 must cross R1 to reach the terminals.  Additionally, with 100-160 operatives and 50 to 120 pieces of equipment present on R1 each night, there is clearly potential for vehicle/aircraft conflicts.  To minimise the risk of such an event, a significant amount of pre-planning was needed to ensure the works and site would be managed in the safest way possible, and rigorous procedures were put in place.

The basis of the procedures comes from another form of transport and dates back to the 19th century, when it was used to great effect on the railways when trains running in both directions needed to use a single piece of track (‘single line working’).  To get round the rather obvious problem of trains meeting head on, any train traversing that section had to be in possession of a ‘token’.  Once a token was released by the signalman the system was locked to prevent another being released (at either end) until the issued one was given to the signalman at the other end of the affected section.  It is this notion of possession that guides the use of the runway at night, albeit by use of a single document rather than a piece of metal.

 

Handover

As is the case at all airports, under normal operating conditions ATC has control of the runways at all times even if one is operationally closed, as was the case with R2 for long periods of the day and night.  However, this cannot be the case while the runway is under refurbishment, so possession of the runway passes from ATC to the contractor.

The process of handover started at about 13:00 each day with a check on the weather conditions to see if it was possible to carry out the work.  This was dependent on the forecast for the evening because if LVP (Low Visibility Procedures) were expected, the night’s tasking would be cancelled.  The final decision would be made later in the day at any time until 20:00.  However, if some resurfacing was scheduled, then the production of the material, or ‘batching’ as it is known, would start quite early, necessitating an even earlier decision on whether to cancel to avoid unrecoverable costs.

At 19:00 the day shift Airport Duty Manager (ADM) handed over to the night man.  The next meeting was at 19:30, which brought together all agencies such as operations (ops) and fire service aiming to ensure everybody was briefed about the night’s works and to check for potential conflicts.  At 20:00 things started to hot up: a meeting was held with the ADM and the contractors, chaired by the Possession Manager Operations (PMO), who is a current ADM at the airport but not the ADM on duty.  The final decision to proceed would then be made.  Potential weather issues were discussed, such as wind direction, which could affect the crossing points on R1, or how the airfield lighting was set at transition.  By 21:30 everybody knew exactly what was happening, right down to the last aircraft to use the runway before it closed.

At approximately 21:30 each night after the pre-arranged aircraft had landed, the ATC watch manager began officially handing over possession of the runway to the ADM via radio.

This triggered the safety procedures for single runway (R2) use.  The pre-arranged lighting configuration to guide aircraft to and from their terminals was introduced, and the crossing points were guarded by the use of barriers and manned vehicles with what amounted to traffic lights.  When the ADM was happy that all was ready, he obtained the PMO’s signature on the possession document.  The PMO liaised with the contractor to ensure they were ready to start work and possession passed to the contractor again by signing the same document.  Then, and only then, could the many vehicles and manpower enter the runway to start the night’s work at 21:40.

Despite the massive amount of work required by the ops team there were only two extra members of staff employed each night; one was the PMO and the other manned the main crossing point.  The second crossing point was only used until the night rush was over and was manned by the PMO.  The crossing points needed manning by experienced members of the ops team with good situational awareness to anticipate movements before they occur.  The PMO’s primary role during the works and handover was the control of site safety (COSS), and constant hazard analysis to ensure any problems are dealt with quickly.  In simple terms, asking the question ‘what if?’ and applying a solution.

Each night up to 160 people and 120 pieces of equipment and machinery had access to the site.

Project

So what exactly happened during those hours of darkness?  The project comprised the following key elements:

 

• Constructing a new sub-station to provide power to the new runway lighting system.

• Creating a new ‘pit and duct’ system around R1, which provided infrastructure for new lighting cables.  This involved fabricating and installing 400 pre-cast pits and 6 miles (10km) of duct-lines around the periphery of R1 and outside the airfield boundary.

• Installing new primary and secondary lighting cables 621 miles (1,000km) and other electrical infrastructure (eg transformers) throughout the pit and duct system.

• Removal of existing light fittings.

• Inserting new light fittings (1,000+) into the existing runway and on approach.

• Miscellaneous drainage repairs ranging from dislodged joints to deformed, cracked and broken pipes and, in some instances, partial collapse or blockages.  Delethalisation of structures on the runway was also required in ‘Cleared and Graded Area’ (CGA) – delethalisation being a regulatory safety requirement set out in Chapter 3 Para 4 [Runway Strips] of Cap 168 that states that drainage channels, catch pits and other essential design features at aerodromes should not constitute hazards to aircraft.

• Resurfacing the full length and width of runway.

 

The most interesting of the elements was resurfacing and the lighting systems.  The standard grooved surface of a runway requires constant attention and rubber deposits have to be removed from the grooves and the removal process affects the integrity of the surface and generates periodic re-grooving to a limited number of times.  Manchester’s R1 was approaching this limit and it was decided to resurface the majority of it apart from the younger extension at the 05 end and the hard shoulders, which do not get any real usage.  Rather than simply replacing standard materials, Manchester chose a revolutionary surface that had only been used at smaller airports in the UK, such as the Isle of Man and Jersey, but which was first applied at Paris/Charles de Gaulle.

This surface, known as BBA, is un-grooved, and did away with constant rubber removal and re-grooving to provide a longer lasting surface while maintaining friction standards to help aircraft stop, particularly in wet or icy conditions.

The runway lighting was even more impressive.  Manchester, in conjunction with the CAA, has been running a trial of LED units on a section of which provided feedback from both aircrew and CAA test flights.  The lights used less energy (bringing a cost and environmental saving) and also provided a clear, crisp, bright white light that does not deteriorate over time.  Existing halogen light fittings tend to become warmer in colour over time and need testing to ensure they remain within the correct parameters, but LED lights work to full effect until they fail, reducing the amount of testing.  The airport became the first in the UK to introduce the lights – on a test basis; initially on Runway 23L, then 23R – when they became available last December.

A new ice alert system has also been installed, with sensors all around the airfield.  Not only does this feed back into the weather forecasting system, but also helps to make the application of 3,434 gallons (13,000ltrs) of anti-icing fluid more efficient.

 

Contractor

Costain was the main contractor on the project and it also maintains the airfield civil engineering infrastructure through a framework agreement that was won by competitive tender in 2004.  This has since been extended by five years on top of the initial five, and will expire in 2014.  Guy Wooley, Costain’s Framework Manager on site, explained the works were not technically difficult; the re-surfacing was easier – being quicker to lay without grooving.  However, the real challenge was getting up to 160 people and 120 pieces of plant and machinery on and off the functioning airport each night and ensuring the site was handed back in a fully serviceable state at the time promised.

One of the major, daily challenges was the ground condition, with old and disused cabling running all around the work area and the old electrical system had to remain in place while the new one was constructed to maintain continuity.

The next key time on the shift’s clock was 04:00 when the ADM, PMO and key Costain staff met to review the works, gauge the runway reinstatement time and to identify any issues that might lead to a delay.  This early morning slot was chosen because it allowed sufficient time to rectify any problems, the most common of which was inadvertent cutting of myriad lighting cables running in and around the runway.  However, if there was likely to be a delay, it also allowed for liaison with NATS and ATC to implement flow control by pushing back departures from European destinations (the long-haul flights would already be in the air).  As aircraft generally carry less holding fuel these days, there was less leeway for diversions – with obvious negative PR and loss in revenue.

 

End of the shift

Once the night’s work was complete, including a thorough sweeping, checks were made for foreign object damage (FOD), surface defects and to confirm work sites had been completed correctly.  The checks were made by the contractors, the PMO and finally the ADM.  There were several key items that needed to be completed and in the correct order before possession of the runway could be handed back to ATC.  No assumptions were made in the process and over-familiarity was avoided by the use of checklists.

The wording used over the radio was set down rigidly to avoid confusion. If one person did not hear what they should in response to their own transmission it was not accepted, thereby avoiding any potential dangerous situation.

Possession of the runway was handed back with the same modern-day version of the steam-age token process, only in the exact reverse of what happened the previous evening.  The ADM was the very last person off the runway before finally handing it back to ATC, maintaining ADM/ATC contact.  This was particularly important as the ADM was ultimately accountable for the airfield, and he or she had to be sure that all jobs had been done correctly.

MAN has built up a considerable knowledge and experience in runway works requiring closure and this procedure no doubt helped tremendously to ensure the nightly process ran smoothly.

Next time you land on Manchester’s main runway, look out the window at the pristine new surface and remember this was no mere facelift.  What you see is the result of a highly coordinated, multi-million pound operation employing cutting-edge technology.

 

This entry was posted in Airports, Contracts, Environment, Features, Ground Handling.

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