worksheet the longitude co-ordinates of the McMurdo waypoint he
mistakenly transcribed the correct figures of 166° 48' as 164° 48' by
inadvertently typing the figure "4" twice. This had the effect of moving
the McMurdo waypoint 25 nautical miles to the west and once in the
aircraft's system the navigation track which then it would follow from
Cape Hallett when under automatic control would be over the[1] Sound
rather than directly to Williams Field.

At this point it should be mentioned that the print-out of a flight plan
shows not merely the co-ordinate waypoints but also a finely calculated
statement of the direction and distance between them. This last
information is obtained independently from what is called the NV90
programme of the computer which is able automatically to calculate the
rhumb line track and distance between each of the respective waypoints
once the co-ordinates have been fed into it. This information forms the
basis for the data required to produce the computerised flight plan. So
that finally when a print-out of the plan is obtained it will disclose
not merely the geographical co-ordinates for each waypoint but the true
track direction and the distance in nautical miles from one to the next.
That last information is needed prior to a flight departure in order to
calculate tonnages of fuel during the prospective journey and
accordingly as a flight proceeds it enables the quantity of fuel already
consumed to be checked against the anticipated consumption in the flight
plan print-out. Thus the precise track and distance is used for purposes
of fuel calculations and has importance as a check in navigation.

All this information is disclosed on page 96 of the Royal Commission
Report where the print-out is shown for the flight plan with the
co-ordinates for McMurdo showing the longitude as 164° 48' east. In the
next column the track direction is given as 188.9° (grid) and the