October 1, 2017 marks the ten-year anniversary since the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) research aircraft Polar 5 began service. In that time, the Basler BT-67 has flown more than 1.3 million kilometres to fulfil essential scientific and logistical duties. In the course of 48 measuring campaigns, predominantly for atmospheric research and geophysics purposes, the airplane has landed on the Arctic sea ice near the North Pole, and at the South Pole.
Polar 5 is tailor-made for polar research: in the span of eleven months, the 65-year-old plane was essentially rebuilt from scratch. The Basler BT-67 is based on a modified Douglas DC-3 (which became famous as “raisin bombers”). The rebuild also provided the perfect opportunity to install the special-purpose equipment needed for survey flights. As a result, Polar 5 can lower the ice-thickness-measuring device EM-Bird and tow it through the atmosphere, while a special port in the hull allows probes to deploy sondes in flight. Thanks to her combination skid-and-wheel landing gear system, the plane can take off and land in even the most remote regions. Upon being commissioned, Polar 5 – supported by 8.1 million Euros of funding from Germany’s Federal Ministry of Education and Research (BMBF) – embarked on her maiden flight to the Antarctic. She first landed on Antarctica on 9 November 2007 and reached the Neumayer Station on 15 November. In the meantime, the plane has flown 14 scientific recording campaigns in six Antarctic summers – not to mention her passenger and logistics flights in the context of the international DROMLAN network.
“A special highlight was a recording flight at an altitude of 4,700 metres, which took us over Dome A, located on the Antarctic Plateau, 4,090 metres above sea level,” recalls Dr Daniel Steinhage, a geophysicist at the Alfred Wegener Institute and one of Polar 5’s ‘frequent flyers’. Dome A is one of several key sites for drilling ice cores in East Antarctica. Radar measurements taken on board Polar 5 allow e.g. glaciologists to investigate the layering and flow behaviour of the ice, and help them work together with climate researchers to find the ideal sites for gathering ice cores, which in turn offer valuable insights into greenhouse-gas concentrations throughout our planet’s history. Since beginning service, Polar 5 has travelled to Antarctica six times and yearly to the Arctic, where it has contributed to 34 research projects. All told, she has completed 48 campaigns in both Polar Regions and flown more than 1.3 million kilometres – the equivalent to 32 trips around the Equator. For nearly six years now, she has also been supported by her sister ship Polar 6, which began service on 28 October 2011. “The excellent track record we had with using this type of craft for scientific and logistical work in the Polar Regions is what moved us to purchase Polar 6. As a result, we can now use both planes simultaneously, and can, for instance, collect data on the same cloud from above and within at the same time,” says Dr Uwe Nixdorf, Head of the Operations and Research Platforms Division at the Alfred Wegener Institute. “That gives us a unique infrastructure for scientific research in the polar regions – due in part to the fact that, with two essentially identical planes, we can easily transfer measuring systems from one to the other as needed.”
Polar 5 also makes flights to the Arctic, and brings researchers to the Greenlandic glacier, where they not only extract ice cores, but also gather data on atmospheric aerosols and trace gases, as well as the distribution of sea-ice thickness, at regular intervals. Yet what AWI atmospheric researcher Dr Andreas Herber remembers best is a very different aspect: “As part of the International Polar Year 2007/08, we picked up one of our colleagues from a glacier in the Central Arctic that was home to Russia’s drifting ice station ‘North Pole 35’. The landing strip on the sea ice was a brand-new experience for us. But it worked so well that we visited the Russian researchers at ‘North Pole 36’ with Polar 5 the following year, to pick up fuel.”
Source: AWI, Bremerhaven