An important task for Voyage 4 last summer for the Norwegian-owned ice-strengthened supply ship Polar Bird was restocking of the Sansom Island Fuel Depot and positioning scientific parties at shore locations. Polar Bird left Davis on 4 December 2001, but an unseasonal gale and heavy seas slowed its progress to Sansom Island.
Helicopter operations to transport fuel and other supplies to Sansom Island began on 7 December over 60 nautical miles, double the distance of a normal fly-off. A large band of pack ice prevented a closer approach. An attempt during a blizzard two days later to move the ship towards open water was stalled by failing visibility.
On 10 December clearing weather allowed two days of flying, in which field parties with all food, stores and equipment were put ashore. But the ship was now surrounded by dense, rafted pack ice consolidated over the next two weeks by northeasterly weather. Two unsuccessful attempts to move confirmed that Polar Bird was beset. A reconnaissance flight on 28 December revealed 47 nautical miles of heavy pack ice between the ship and open water.
During the besetment, all remaining fuel was delivered to Sansom Island and the ship was maintained in readiness for an eventual move. While Aurora Australis travelled west from Casey to assist, taking on expeditioners by helicopter and transporting them to Mawson, ice reconnaissance flights were maintained from Polar Bird. Mawson-bound expeditioners aboard Polar Bird continued field training, conducted their own version of the Olympic Games, played a variety of competitive sports, organised quiz nights and theme nights, and celebrated both Christmas and the New Year.
On 11 January cracks around the vessel enabled it to move under its own power some 21 miles to the north, where it was met by Aurora Australis. At this point the weather changed again, preventing both vessels from moving for another 24 hours. Aurora Australis, with its greater engine power, was able to manoeuvre around Polar Bird and break it free from the ice before clearing a way to the open sea. The complex operation ran from the early morning of 13 January until the following day, when both ships entered clear water and could proceed to Australia.
Joe Johnson, Voyage Leader, Voyage 4 2001–02