We are perfectly aligned for a touchdown at Kittilä’s runway 34, the gateway to Finnish Lapland. Situated beyond the Arctic Circle, this 2500m long runway is often covered in snow. The wintery condition presents an additional challenge to the flight crews, necessitating special procedures.
(Not) Just another day at the office
Around five hours earlier, a long workday begins that will take us directly to the Winter Wonderland and the northernmost destination in our route network. Destinations like these provide a welcome change in our schedule, offering not only an "exotic-sounding" destination but also a series of exciting challenges.
The Challenges of Flying beyond the Arctic Circle
But what makes "winter weather" so demanding? Most notably, snow and ice-covered runways significantly lengthen our braking distance. Additionally, precipitation accumulates on the aircraft. This is particularly critical on the upper wing surface, as frost or a layer of snow could severely degrade aerodynamics. Furthermore, the extreme cold affects the altimeter, and as we approach the magnetic North Pole, our compass becomes increasingly inaccurate.
Contaminated Runway
Operating from a contaminated runway offers similar challenges as for roads. The reduced friction coefficient increases stopping distance and impairs controllability. However, taking off and landing from a contaminated runway is certified and completely safe. Especially harsh winter conditions or an intense downpour may render the runway "contaminated. " This means that its surface is neither dry nor wet but is covered with snow, slush, ice, or standing water to name just a few. Although airport ground staff works tirelessly to treat runways, complete clearance may not always be possible, leading to temporary closures. In commercial aviation, everything is based on limitations, rules, and procedures. Therefore every takeoff and landing is calculated beforehand with the prevailing conditions. It allows us to accurately know how long our landing roll will be or what thrust settings we need to safely take off. It certainly also covers the unlikely event of an aborted takeoff and assures sufficient remaining runway to come to a stop.
De-Icing
Flying in cold temperatures often necessitates de-icing. The build-up of ice, frost, or lingering snow can modify the wing and tail shapes, diminishing lift while increasing weight and drag. Hence, it's imperative to eliminate these contaminants before takeoff. Once all passengers are on board, the de-icing procedure will either occur at the parking position, or the pilots will taxi to a dedicated de-icing pad to initiate this process. Stay tuned for the February issue, where I'll delve deeper into the intricacies of de-icing an aircraft.
Instrument Errors
Flying in the Arctic affects our instruments. Cold temperatures impact the altimeter, while the variation influences the magnetic compass.
Cold Temperatures
The altimeter, a pressure gauge, is inherently susceptible to temperature deviations. An error occurs when the altimeter indicates the same altitude irrespective of the temperature, while the actual height (true altitude) differs due to changes in air density.
"From Warm to Cold, You Won't Get Old!"
In warmer temperatures, the altimeter may indicate a lower altitude than actual, and in colder temperatures, it may erroneously indicate a higher altitude. This discrepancy is crucial when flying in clouds and relying solely on instruments.
Compass Error
Changes in the magnetic field at high latitudes impact the compass. Although the magnetic compass holds less significance in modern airliners, given the prevalence of GPS equipment and gyroscopes in today's navigation, it remains crucial to consider the variation – the angular difference between the compass and true direction. Did you know that the earth's north magnetic pole is located somewhere to the north of Canada and not at the true North Pole? This difference causes the compass to indicate an error called variation. It is the angular difference between the direction measured by the compass (towards the magnetic north pole) and the true direction (geographic north pole). And the further north you get, the more error you experience. Pilots find the information about the variation for any position on their aviation chart. It is named east or west to indicate the side of the true north on which the compass north lies. For instance, at Thule Air Base (BGTL) on Greenland's northwest coast, the variation is almost 42° W.
Welcome to Winter Wonderland
As we enter Finnish airspace, the sky clears, unveiling breathtaking views of a frozen world below. The cold beauty is both captivating and challenging, with an otherworldly allure. For me, Finnish Lapland embodies the essence of a winter wonderland. The surreal beauty of snow-covered landscapes and frozen expanses, paired with the serene stillness and the enchanting dance of the Northern Lights, encapsulates the captivating allure of this Arctic region.
Anticipating a challenging approach, we complete our meticulous approach preparations well in advance and maintain full focus, gearing up to execute an ILS approach for a landing on runway 34. Minutes later my First Officer skillfully pilots the aircraft towards the runway, executing a precise and smooth touch down followed by a swift deceleration. The braking action proves excellent, allowing us to promptly vacate through one of the earliest exits. As expected, the tarmac and taxiways exhibit more contamination, a consequence of the ground staff's primary focus on runway clearance. Navigating with caution, I slowly taxi the aircraft to our assigned stand. Shortly after, our guests disembark, and we bid them farewell, extending our best wishes for a delightful time in Winter Wonderland with Kontiki Reisen. With the last passenger disembarked, our attention swiftly shifts to preparing our Airbus A220 for the journey home.
About the image
The January image in the 2024 edition of my photo calendar, titled "Welcome to Winter Wonderland," encapsulates the mesmerizing cold beauty of this otherworldly region. Flying to the Arctic Circle requires profound knowledge of the unique challenges posed by such operations, effective crew coordination, and continuous flight monitoring.
Shot on a Canon EOS R5 + Sigma 35mm F1.4 DG HSM Art, ISO100, f/6.3, 1/320sec
About "Behind the Image"
In my photo calendar "Up in the Sky" I get to share my favorite aviation pictures with you. This blog series will complement the product and will tell the story about the moment the picture was taken. It will also share comprehensive information about what happend on the flight deck and how the picture was created.
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