Monday, March 15, 2010

Wilkins Runway, Antarctica

If you had to choose between Iceland, Greenland and Australia as the country which built a runway out of compacted snow and ice on top of a glacier you would be forgiven for discarding Australia straight away. And you'd be wrong.

I found the ad below in the aviation section of The Australian a while back, which reminded me of the existence of the Wilkins Runway, a 3500 meter-long (that's 11,500 feet) runway built a few years ago in Antarctica.

The scientists and support staff working at the various scientific bases over there can now enjoy the convenience of a weekly airline service, which beats having to spend two weeks on a boat crossing some of the roughest seas on the planet.

Skytraders operates this very peculiar airline with one Airbus A319 fitted with long-range tanks. The flight from Hobart, Tasmania to Wilkins Runway takes approximately 4.5 hours and takes place about once a week during the summer period.

Since meteorological conditions are rather unpredictable and unforgiving, and alternate airports are few and far between in that corner of the world, the airliner always has the option of flying all the way back to Hobart. That's quite smart, since it also eliminates the need for refuelling in Antarctica.

Photo by AAD. © Commonwealth of Australia.

The runway is actually made of hard blue ice on top of which a layer of compacted snow was laid down. Snow provides better grip than ice and also does not melt as much under the sun. Still, the Airbus 319 Flight Policy issued by the Australian Antarctic Division says that at times during the summer, flights will be constrained by temperature and friction issues at Wilkins Runway. Flights during this period may only occur during “night” hours.

There is no entry in the ERSA for Wilkins Runway, but an RNAV approach can be found. The runway is called 09T/27T. The letter T refers to the fact that all headings are in degrees true, as opposed to degrees magnetic. That's what happens when you get too near a magnetic pole: magnetic declination is too large and unpredictable to predicate aerial navigation on compass readings. The aerodrome chart mentions the existence of a PAPI on 09T.

Another thing I didn't know is that the Australian Antarctic Territory is the largest chunk of Antarctica. Amazing what you can learn through an interest in aviation.


Chris said...

Good article about this in the latest issue of Australian Aviation. The magnetic variation at Wilkins is roughly 100 degrees west.

Julien said...

Yes, I realised the photo I chose for illustrating the blog post also made the cover of Australian Aviation, but only after I posted it, promised!

I wonder what RAIM predictions are for Antarctica. Since all satellites are on a polar orbit, maybe weird things happen near the poles. I tried to type the coordinates of Wilkins Runway into NAIPS but it won't accept extreme latitudes.