"That never really gets old,” said Fred Jay, the territorial government project director overseeing upgrades to a runway at Whitehorse’s airport as a 737 powers up its engines and surges down the parallel strip of pavement for takeoff.
Since April, Jay’s workplace has been the runway nearer the terminal at Erik Nielsen Whitehorse International Airport where a crew that often numbers more than 70 workers has been resurfacing the aging pavement and conducting a range of subsurface upgrades.
Leading reporters on a project tour on Sept. 3, Jay explained that work had been going on at the runway since April 15 and that the runway will be back in service by Oct. 15. The scope of this year’s work included the resurfacing, replacement of drain pipes and electrical upgrades for the northern half of one of the runways. Next year will see similar work done on the southern half.
The runway has received a fresh layer of asphalt in the past but Jay explained that cracks in the underlying concrete, which dates back to the building of the original runway in the 1940s, reflect through the asphalt and cause it to crack as well.
“Unless you get rid of the root of the problem, which is these old concrete panels, those cracks will keep coming back,” he said.
“Part of the work here is to remove that concrete. We've got a fresh gravel bed, and then we're asphalt on top. The only cracking we're expecting is after a few years, once the asphalt sort of gets settled in, they're called temperature cracks. So when it gets really cold, it'll crack at basically every 100 metres, just as the asphalt’s shrinking. So those ones are more manageable. They're predictable. They're ones that we can control, and we know roughly where they're going to be.”
Jay said that the danger to aircraft from cracking pavement is the possible ingestion of debris into the planes’ engines. This was the motivation behind hot-in-place asphalt resurfacing done on the runway about five years ago and of the complete resurfacing started this year. He said the new surface will have a 20 to 25-year lifespan before significant resurfacing is needed again.
He said the process is similar to paving a street but with larger material in the asphalt creating more friction and making it easier for planes to stop. Reinforcing fibre is used in the asphalt to keep temperature cracks smaller and easier to maintain and Jay said asphalt binders geared for the low temperatures Whitehorse experiences in the winter are being used.
The upgraded runway sits on basically the same footprint as the original, but it is slightly narrower, which Jay chalks up to the switch to metric measurements rather than the imperial units employed in Canada when the runway was first laid down.
He noted that the project includes reorientation of some of the airstrip’s taxiways to improve traffic flow for taxiing aircraft and assisting with snow clearance in the winter.
Also being moved are some lights at the end of the runway allowing for the use of its full footprint by aircraft. Jay noted that Runway End Safety Areas, or RESAs, designed to limit damage to aircraft if they overshoot or undershoot the runway on takeoff or landing, are being required at larger Canadian airports and that the changes bring the Whitehorse airport closer to this standard should it be required.
“I don’t believe we had to implement them in Whitehorse yet just because it goes by passenger counts but we're going to, I think, soon. So we're prepping for it,” he said.
Along with improvements to the paved surfaces themselves, Jay explained that more modern lighting along the edges of the runway have been installed. He said that the new lamps are LED rather than the old incandescents and are rated for 50,000 hours of illumination compared to about 5,000 for the old ones. While much of the old electrical wiring was buried directly in the ground, Jay said conduit has been run on the new project making repairs easier if there is a break.
On Sept. 3, work was going towards improving the catch basins and drain pipes alongside or underneath the runway and taxiways. Jay said the new drainage is better quality than the old and that the underground piping is mostly complete with the southern portion of the runway, to be repaved next year, mostly drained by ditches.
The work on the runway, with the adjacent one still in operation, required careful coordination with air traffic control. When runway crossings were required, Jay said the surface was regularly swept to keep it clean.
Flatiron Construction is the general contractor building out the runway with several local subcontractors also working, Jay said.
“Things have been going well with the contractor. Relationship’s going good. They've been very professional and quality minded,” he added.
The plan is to return the runway to use by mid October but Jay said some off-runway work may continue later into the fall. Next year, the project will turn to the southern half of the runway with another April to October closure anticipated.
With another runway upgrade project in the territory as an example, Jay said the new surface might draw the enthusiasm of local aviators. He recounted a story about a plane in the air and circling, waiting to be the first to land on the new runway surface at the Dawson City airport after it was fixed up a few years ago.
Contact Jim Elliot at jim.elliot@yukon-news.com
