Auckland Airport has brought forward work on its runway as the number of flights remains at a fraction of normal.
The landing zone at the eastern end of the runway had deteriorated and chunks of it were breaking off leading to temporary closures earlier this year, alarming pilots, disrupting the travel plans of thousands and infuriating airlines.
The airport had budgeted and planned runway pavement replacement work but it was not due to start until the last quarter of this year. However, it said today construction work would start on the $26 million project in two weeks.
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It said the Covid-19 outbreak and the cut in flights, particularly large long-haul aircraft, gave it a chance to have another look at the proposed construction windows.
Andre Lovatt, general manager of airport development and delivery, said aircraft movements were 90 per cent to 95 per cent lower than a normal busy day.
''This project has been planned for some time, but it was clear that we had an opportunity to bring construction forward to the earliest available time while runway movements are at an all-time low.''
Aircraft will continue to use the shortened runway rather than using the taxiway as a temporary one.
''Safety continues to be our number one priority, and I'd like to thank our aviation partners for working alongside us in order to create a robust plan for undertaking this work.''
Brian Perry Civil will employ 150 people over the next three months and involve the removal and replacement of 280, 36sqm slabs in the eastern end of the touch-down zone.
The project will see 12,000 tonnes of concrete laid 500mm thick to create the heavy industrial-grade pavement necessary to withstand landings of some of the heaviest and largest aircraft in the world, taking off at weights of up to 500 tonnes.
The existing runway will be shortened by 1.1km during the 8- to 10-week construction period.
The company said this method, called a displaced threshold, was a common practice at airports worldwide and allows work to be carried out safely while aircraft continue to operate.
Using an existing taxiway (contingent runway option) was also considered but the added complexity of converting the taxiway to a safe, operational runway in a short timeframe meant it was not possible.
Lovatt said in normal circumstances, a displaced threshold method could result in the need for airlines to reduce aircraft weight, but with fewer fully laden aircraft flying it was not anticipated.
The runway was originally built in 1965, has been developed and renewed over the years as part of a programme of work that follows recognised standards and is overseen by independent experts.
Because of the crisis hitting aviation and uncertainty about the industry's future, development work on a second runway to the north of the existing one had been suspended.
Auckland Airport has deferred the vast majority of its infrastructure development programme - a series of projects that had been designed to cater for growth in passenger numbers, projected to double by 2044.
"It's extremely disappointing to put on hold much of the $1.2 billion worth of construction projects already under way around the precinct prior to the Covid-19 outbreak. But with no certainty around when the aviation market will recover it just isn't realistic to keep progressing these projects at this point in time."
The safety case for the runway works has been reviewed and approved by the Civil Aviation Authority.