Four errors found in flight plans

Press, 29 August 1980, Page 3

Four errors found in flight plans

PA Auckland Four errors relating to Antarctic computer flight plans were described yesterday by Mr Justice Manon at the DCIO crash inquiry at Auckland.

Earlier, the commission heard how an incorrect longitude co-ordinate for McMurdo Base was typed into the computer flight plan. Charles Brian Hewitt, chief navigator for Air New Zealand, said he inadvertently typed the longitude for McMurdo as 164.48 degrees east rather than 166.48 degrees east. The mistake occurred in July or August, 1978, when

Mr Hewitt prepared a computerised flight plan for more regular Antarctic scenic flights. Mr Hewitt, who typed the computer co-ordinates from a worksheet, said it was standard practice to check the figures displayed on The computer against those on the sheet.

“I did, but in this case, I did not detect my error,” he said.

The two-degree error, which placed pilots about 27 nautical miles east of i McMurdo Base, remained in ; the flight plan until just before the fatal flight. About two weeks before : the crash, an Antarctic flight

pilot, Captain L. Simpson, reported that there appeared to be something wrong with the position of McMurdo. Navigation section staff noted a 10-minute difference between their original figure (166.58), which was thought to on the computer flight plan, and the figure given for McMurdo on more up-to-date charts.

Navigation staff were instructed to amend the co-or-dinates, which became 166.48 on the computer flight plan. This route, as was originally intended, took the plane over the top of Mount Erebus. During cross-examination of Mr Hewiti, his Honour described three more errors. “We have the error whereby Captain Simpson’s disclosure was apparently misunderstood, was it not?” he asked Mr Hewitt. Mr Hewitt: Yes, sir. The next error was apparently that the navigational section did not double-check when investigating Captain Simpson’s query. The fourth error related to the preparation of a flight plan for one of the controlling aviation authorities along the Antarctic route. A figure had been placed in the wrong column. His Honour: Does that strike you as a remarkable sequence of errors made by perhaps five different persons on the same matter? Mr Hewitt: Yes, sir. It is very surprising. The inquiry will not sit next week. The hearing of evidence is expected to continue until mid-October.