designated route was one which used Cape Hallett on the north-eastern
point of Victoria Land as the first southern waypoint on the continent
itself en route further south either to a point adjacent to the Williams
ice landing field (near Scott and McMurdo bases) or alternatively the
south magnetic pole. One or other became the southernmost waypoint, the
magnetic pole destination being used at the discretion of the pilot if
weather conditions made the McMurdo area unsuitable for sightseeing.

Scott and McMurdo bases are located close together at the south-western
tip of Ross Island which forms the eastern coast of McMurdo Sound. On
the island there are four volcanic mountains including Mt. Erebus, the
highest, at 12,450 feet. The Sound itself, which is about 40 miles long
by 32 miles wide at the narrowest point, lies between mainland
Antarctica and Ross Island and for most of the year it is covered with
flat sea ice.

The first two flights in February 1977 took place with the necessary
approval of the Civil Aviation Division of the Ministry of Transport and
after clearance with the United States naval authorities who control the
air space in the vicinity of McMurdo Station. Those flights followed a
computer-controlled flight track to Cape Hallett thence directly over
Ross Island and Mt. Erebus at the stipulated minimum height of 16,000
feet to the McMurdo waypoint. The co-ordinates of that waypoint had been
written correctly into the flight plan as 77° 53' south latitude and
166° 48' east longitude. Three of the pilots who flew to the Antarctic
in November 1977 were available to give evidence and, like the two
earlier pilots, they agreed that at that time the flight plan followed a
track from Cape Hallett to the McMurdo area which passed virtually
overhead Mt. Erebus. However then and on subsequent occasions the
sightseeing aircraft to the McMurdo area arrived in the general vicinity