ANTARCTIC Antarctic air ops Antarctic summer is peak season for the British Antarctic Survey By Captain Robin Evans, Senior Log Contributor A glaciology field camp on the Pine Island Glacier, West Antarctica ntarctica is a continent of superlatives: the coldest, windiest, highest, driest desert on Earth. At 150% the size of the US, its the only continent with no native human population. However, it hosts a seasonal scientific population of 5,000 for the austral summer (October-March), which is heavily reliant upon air support. The British Sector occupies a cone radiating from the Pole to 60 south and 20-80 west. This covers the Antarctic Peninsula, stretching towards South America Chile is 1,000km away over the notorious Drake Passage. This tactical connection explains the significant overlap of British, Chilean and Argentinian claims, neutralised by the Antarctic Treaty. Enforced in 1961, its a peaceful, scientific co-existence that transcends geopolitics. The British Antarctic Survey (BAS) was formally setup the following year to support interdisciplinary research in the polar regions. Antarctica is synonymous with the heroic era of 1897-1922, particularly the Amundsen/Scott race to the South Pole. Then came the mechanical era, aircraft first used along the coastal margins before forging inland. Since these earliest days, some things have actually changed very little, explains Rod Arnold, Head of Air Operations at BAS (UK) headquarters outside Cambridge. We stick to tried and tested methods for some of the camping and cooking. Originally a biologist, Arnold is a veteran of 10 Antarctic campaigns and runs a team of 20, half of them pilots. His role focuses on planning and managing the seasonal flying programme while considering how best to serve the scientific community. BAS permanently operates from two key stations. Its operational hub in the Antarctic, Rothera Research Station, lies halfway down the Peninsula, serving as an initial staging point between South America and the Falkland Islands and wider Antarctica. At the Peninsula base is the compacted, blue-ice runway of Sky-Blu, at 4,700 elevation. From here, a network of fuel depots and camps extends to the Pole. Sky-Blu used to be deep-field; its now the centre of our field operations, says Arnold. The aircraft have really helped open up the interior. That interior is immense: the BAS network is equivalent in size to continental Europe, served by a single Dash-7 and four Twin Otters. Twinnebago Aircraft are used for the key roles of logistics and science. The Dash carries out bulk handling onto gravel or ice runways, including shuttles to the Falklands. The ski-equipped Twin Otters are rugged workhorses, serving unprepared sites in the interior. Our field logistics are driven, critically, by the aircraft, says Arnold. Fuel is the lifeblood of the operation. It takes seven hours flying and six drums of fuel in a Twin Otter to deliver four drums from Rothera to Sky-Blu; the Dash can drop 16 drums twice a day. The embedded value of fuel or other supplies is proportional to the number of hops and logistical challenges en route. Arnold refers to this as a fuel pyramid, prompting comparisons of an earlier aviation challenge that took place nearby: the 1982 Black Buck raids on the Falklands. He notes a recent positive: The RAF has recently started airdropping fuel, which is a massive short-circuit of our conventional distribution planning. To overcome continual snow accumulation, a barrel atop a pole is used to mark remote caches. The barrel acts as a visual marker and appears on the weather radar, says Arnold. We spend a lot of time just finding and then digging up our fuel. Sometimes, we have to fly a whole team in just to raise the fuel above the surface again. Theres a more insidious force at work: Antarctica is alive with ice streams, steadily grinding towards the coast. Some of these streams move more than a kilometre a year, depending on where you are. One party found their fuel to be moving at 2m per day. Scott and his two remaining companions, Wilson and Bowers, who died in 1912 in their tent on the Ross Ice Shelf, demonstrate this effect. Still compressing into the ice, they are slowly shifting towards the coast. The trio of ancient mariners will eventually return to sea inside a calving iceberg. Airborne science often focuses on geophysics, aiming to picture the continent without its icy cover, kilometres thick. Aircraft carry magnetometers, gravimeters, and wing-mounted ground-penetrating radar. The Twin Otter fleet has flown 593,000km of Antarctic geophysical survey: straight and level paths with a calculated overlap. Indicating finely honed skills, regular practice and an ideal machine for the job, Arnold highlights the precision achieved by the pilots: Less than 10m off-track after five hours of survey and sometimes two sorties a day. This is achieved entirely without automation, though the aircraft benefit from a 2015 Garmin 950 refit. The field ops manager will give the morning briefing. The pilots assess the weather and make their decisions, says Arnold. Operations are typically single-pilot, with a second crew member, usually another trade. There are two good reasons for the buddy system in single-pilot work, says Arnold. Its really motivating for station staff and for safety: our biggest risk is carbon monoxide poisoning. Antarctic flat white is more problematic, crews inevitably spending time camping in the field. The pilots nickname for the Twin Otter, the Twinnebago, reveals the interdependency of crew and machine. If you are stuck, its often somewhere relatively benign, caused by a delay at the destination being out of limits, explains Arnold. In these situations, the crew pitch camp. We use the traditional cotton tents, not synthetic ones; at 40kgs, theyre not lightweight but are suitably proven; likewise the stoves. Food and supplies are always carried; resilience and good humour are also required. Multiple HF radios and satellite phones are carried, and pilot preferences typically additional gloves and sunglasses. Aircraft are protected with nacelle blankets and Tannis heaters (electrical pads shielding batteries and oil) though the Twin Otter is built for overnight cold-soak at -35C. Toppling gyros Aptly, Antarctica appropriately turns many conventions on their head. Polar vocabulary evokes the international origins of exploration: dunes of windblown snow set like concrete are sastrugi, a Russian term. Of Inuit origin is nunatak: the exposed tip of a mountain emerging from ice kilometres deep. Runways can be blue ice, gravel or groomed skiways. Particularly if crosswinds dictate, it can be safer to assess your own site through satellite photography and trailing skis to physically check the snow surface. Field elevations vary from sea level to 9,300 at the South Pole. Antarctica is notorious among pilots as the home of 3,794m Mount Erebus: site of the 1979 Air New Zealand disaster. Knowledge is still being built on the surveys of the first pioneers. In 2017, Mount Hope was newly declared the highest point in BAS territory at 10,654ft, the significance of a 1,000ft increase not lost on its pilots. Many lateral adjustments also occurred during the same survey; mountains shifted to their correct positions. An internal cartographic team collates this vital knowledge, producing paper and digital mapping. External navigation systems are minimal: Rothera has NDB/DME and GPS approaches, navigation otherwise nominally VFR. Reference can be magnetic, true or grid depending upon the area involved: the Magnetic and Geographic Poles lying far apart. All time zones converge towards the pole, rendered meaningless by the permanent daylight of Antarctic summer. The work pattern and time zone is dictated by where the operational support is based, initially our forecaster at Rothera, explains Arnold. If based out of McMurdo or the Pole, we would switch to US time and their operational support, particularly as their forecasts would be issued in their time zone. The working day might also be shifted according to the temperatures: summer averages range from -5C at Rothera to -50C at the Pole. Project time lost because of weather can be made up, so flexibility is granted to crews to complete work. Leaving a hardy complement of overwintering staff, all aircraft migrate to Canada for servicing at the end of an Antarctic season nine days and 50 hours of transit, with a day off somewhere in South America. It takes three days just to get through Chile, says Arnold. Staff are now likely to participate in collaborative science on the journey. We do reasonably complex atmospheric science work and the transit home will involve some science en route, Arnold adds. A recent project involved monitoring forest fires, coinciding with a calibration pass of a European Space Agency satellite. Pilots are then likely to find themselves in the Arctic during the northern summer. Arnold observes: Our science is becoming much more international and not exclusively polar-focused. Antarctic realities can make basic tasks extreme pilots are responsible for every aspect of their flights: fuelling, loading, cleaning and servicing Careers Historically, BAS pilots followed the RAF mould, but times have changed. The background of our pilots is very well spread, says Arnold. Noting that each pilot community has its own strengths, he knows diversity enables the best team. Coming from airlines, youre good at following procedures and the processdriven format. The minimum requirement is 2,500 hours. We do look for a thread of single-pilot within that, he explains. Antarctic realities can make even basic tasks extreme, covered on predeployment survival training. Pilots are responsible for every aspect of their flights: fuelling, loading, cleaning and basic servicing. Being good with a snow shovel is vital. You are pretty much learning for the first season; the envelope of exposure opens up very slowly. We want judgement to be based upon experiences: weather, icy runways, huge terrain, with different things taken from different colleagues. Its a learning process that leads to the best-rounded pilot. Pilots can expect to fly around 400 hours per season, with opportunities to specialise. With increasing diversification of airborne science around globe and calendar, they wont fly the Antarctic summer exclusively. If youve worked a UK summer campaign, youd probably get an Antarctic shoulder season off or a mid-season break, notes Arnold. Were more flexible than we used to be. We have to invest a lot in the pilots; Id rather have them on the books for longer and work more flexibly in order to keep them. Archive More details of BAS operations can be found at www.bas.ac.uk Inclusion herein is no suggestion of industrial association An indicator and archive for the planet, Antarctic science has become particularly prominent in recent years. The historical composition of our atmosphere is frozen into the ice, secrets unlocked by drilling ice cores. Elsewhere, we now understand its vast ice shelves are warmed by air above and water below, threatening sea-level rise. These are believed to act as dams against the pressure of ice pushing down from the interior notably the Thwaites Doomsday Glacier. The globe depends on this knowledge to inform future policy. All passengers depend upon their pilots, but at BAS its for basic survival. A visiting scientist notes on their blog: Half-human, half-aeroplane. The only pilot Ive taken my tent down for in the field before landing: the highest compliment I could give an Antarctic pilot. It sounds like being on top of the world, at the bottom, depending on how you think of it. Pilot Steve King checks his aircrafts fuel before a sortie from Sky-Blu Lake Ellsworth drill site, a freshwater lake below several kilometres of ice Blue ice runway of Sky-Blu, with vehicle of ice cores in background One of the highest peaks of Adelaide Island, site of the Rothera Research Station Pyramid tents in the Heritage Range, Ellsworth Mountains Fuel digging at Sky-Blu, a job often carried out by hand and shovel elsewhere on the continent Twin Otter VP-FBL dwarfed by Mount Barrie, Adelaide Island