Enter the past:  The DC-3, or C-47 military variant, is intermediate in size and range between the Hercules and Twin Otter, and is one of the few types of aircraft that can be fitted with skis.  The first plane to land at the south pole was a C-47.  However, all of the existing airframes are very old and not suitable for sustained operations of the type we need for scientific exploration.  Fortunately, a company in Wisconsin gives these airplanes a second life by completely restoring them from the bare frame, adding more powerful and safe turbine engines, new electrical and fuel systems, flight instruments, you name it.  They even lengthen the fuselage by over a meter.  The airplanes are essentially new when they roll out of the facility.

The LC-130 Hercules (left) and C-47 (right).

Our project saw the need for such an aircraft and undertook the modification of one to conduct long-range airborne surveys in Antarctica and Greenland.  Last season in Antarctica we proved its capability by surveying a vast, largely unknown part of East Antarctica using fuel and facilities at the coastal stations of McMurdo (US), Casey (Australia), and Dumont d’Urville (France).  We made two stops at Concordia Station (French/Italian) in the interior and obtained about two dozen barrels of fuel there, but that was the only interior resource we used.  We were also able to pack up and move ourselves between these stations while conducting surveys along the way.  This is a first, and has opened the door to a new era of Antarctic exploration.

I have included some video of our unique aircraft and team members in action.  In the next installment I’ll explain a bit about radar and show you some data that we’ve acquired here, since that provides the first and best picture of what is below the ice.  Stay tuned.

In the 1970’s, an international effort to fly ice-penetrating radar over Antarctica resulted in the first rough maps of the sub-ice world.  A ski-equipped Navy LC-130 Hercules was outfitted with radar and flown for long distances.  This reconnaissance was invaluable, but the program went by the wayside after the specially modified airplane crashed doing other work.  The concept was largely put aside until the early 1990’s when glaciologists and geologists got together and tried again.  By this point, it was clear to some that critical additional information could be obtained by including other measurements, namely gravity and magnetics to help understand the geology beneath.  Incredibly, the scientists stuffed all these instruments and a laser altimeter (we didn’t have satellite laser altimeters then) into a much smaller aircraft, a deHavilland Twin Otter.  The Otter is much cheaper to operate and supportable at temporary field camps, so it was perfect for high-resolution studies of specific problems.  

A ski-equipped LC-130 Hercules with jet assisted takeoff (JATO).

Field camps were built each season and LC-130’s delivered fuel for the Twin Otter to use.  This went on until 2001 and then again in the 2004-05 season, and many discoveries were made; however, the Twin Otter just can’t reach the deep interior without heavy support, and this has become very expensive.  Such resources are also very limited.  LC-130’s are very costly to operate, are much larger than needed for this type of work, and require a huge ground crew to support.

The Twin Otter.

The Twin Otter flying over Thwaites Glacier Remote Field Camp.

Having outstripped the capacity of Twin Otters, what next? In my next dispatch, I’ll tell you about what might seem an unlikely platform for Antarctica research: a twin engine aircraft that first saw action during World War II.

This one-of-a-kind airplane features an array of instruments for studying the East Antarctic Ice Sheet and the bedrock below: radar, a magnetometer, laser altimeters, and a gravity meter. Skis allow the team to land nearly anywhere in Antarctica if necessary.

The specially-quipped C-47 aircraft is designed to conduct long-range airborne surveys in Antarctica and Greenland.

The East Antarctic Ice Sheet is the sleeping giant of the cryosphere: it covers more than 95% of the Antarctic continent and locks up more than 60% of the world’s supply of fresh water. Considered much more stable than its smaller counterpart in West Antarctica, scientists are turning more attention to studying the history, structure and dynamics of this mysterious icy world. Instead of taking the stability of the ice sheet for granted, scientists from many different countries are digging into East Antarctica’s climate history to help predict how this vast ice sheet could respond in a warming world.

Graduate students Dusty Schroeder (foreground) and Jamin Greenbaum (rear) monitor instruments during a survey flight.

As a member of a research group at the University of Texas, Austin, Jack Holt participated in a multinational project called ICECAP to survey an enormous, unexplored part of the East Antarctica Ice Sheet. Building on their research experience of the last two decades, the UT team employed a ski-equipped aircraft outfitted with unique instrumentation, including an ice-penetrating radar capable of mapping the surface, internal layers, and the bottom of the ice. Other instruments revealed information about the density and type of the underlying rocks. The aircraft was also fitted with a suite of secondary instruments including specialized GPS receivers and cameras. One of the goals of ICECAP was to find the oldest ice on the continent, the site of a future ice-coring project to unlock climate records that go back a million years.

Data from the ICECAP project will help scientists understand how the East Antarctic Ice Sheet, with its enormous supply of fresh water, might react to changing environmental conditions. The ice in the target area is generally over 2 miles (3.5 km) thick and the bedrock lies mostly below sea level, making this ice potentially more likely to make a rapid contribution to sea level rise than the ice sheets in Greenland or West Antarctica. But the largely unknown continent buried beneath is also important for forecasting how the ice might respond to a warming world: The slope and roughness of the ground, the presence of water (including subglacial lakes), and the type of rocks are all factors.

ICECAP season 1 flight lines.