CRASH OF LOCKHEED

Evening Post, Volume CXXXIV, Issue 7, 8 July 1942, Page 3

CRASH OF LOCKHEED

INQUIRY CONTINUED

DIRECTION-FINDING AIDS

Evidence relating to air navigation aids was heard yesterday at the continuation of the inquiry into the circumstances of the crash of the Union Airways liner at Mount Richmond on May 7', when three passengers and two pilots were killed. Mr. W F. Stilwell. S.M., presided, and with him on the board were Squadron Leader G B. Bolt and Captain O. Garden Dr. Kf. A. Foden appeared for the Department of Civil Aviation. Mr. D. W. Virtue for Union Airways, and Mr. H. Mitchell for Mrs. Johnston, widow of one of the pilots. Thomas Reynolds Clarkson, radio telegraph engineer of the Post and Telegraph Department, said that the reliability of bearings in mountainous country was very poor because of distortion in the path of transmission, similar to that which affected sound waves in the same conditions and caused echoes. Check bearings were used to find out whether any errors had arisen in the apparatus at the radio station. Accordingly daily observations were taken on a fixed station. ■ The evidence showed, continued witness, that only one bearing was asked for and obtained from Blenheim radio "The particular sector to the northward of Blenheim," he said, "is one in which considerable errors had been experienced and is considered doubtful. A Series of observations with Blenheim would have been an additional aid to the pilot." Dr. Foden: Does the Department concede that there is room for any improvement in the reliability of the Nelson station?*-The present equip, merit is operating lo its maximum efficiency There is a superior type of equipment, but that at Nelson is in accord with the practice abroad for the type of assistance envisaged. Cross-examined by Mr. Virtue, witness said that no steps were taken to test the accuracy of the logs by an | outside check. | Were you advised that the Controller j of Civil Aviation was discouraging airmen from using these stations for navigation purposes?—He said that he had reason to believe that the stations were being used as a means of navigation. And he wanted that practice discouraged?— Yes. BEARINGS DEFINED. Witness defined a first-class bearing as one which might be regarded as accurate to within plus or minus two degrees; a second-class bearing to within plus or minus five degrees; and a third-class bearing to within plus or minus ten degrees. He said that the term "swinging' was a local description, and if he saw it used he would ask the operator why he described it in that way. It was possible that the operator might use the term for another meaning in direction finding practice. It might mean the method employed in taking a bearing. Mr. Virtue: Are your operators fully efficient?— The Nelson station was working accurately at the time of the disaster. And were the bearings sent out accurate? —I have no information to make me believe that they were incorrect. • In reply to a further question witness said he considered that the operating staff was efficient. Flight Lieutenant J. M. Buckeridge, Acting Controller of Civil Aviation, said he did not consider that delay in the release of the Nelson air station for general use had any bearing on the accident. Irrespective of calibration, the station was still capable of getting a plane overhead provided the pilot was flying high enough to clear any terrain. After the accident he obtained a draft of the proposals which Commander Johnston, one of the pilots of the plane, had prepared for an operations manual covering the route. Commander Johnston suggested that a minimum height of 5000 ft should be maintained until the descent began. Witness thought the accident proved that that was not sufficient height Replying to Mr. Virtue, witness said he thought the radio operator at Nelson was working under difficulties; and his log broke down. The hearing was adjourned until tomorrow.