AMANA INQUIRY EXPERT EVIDENCE ON ENGINE CORROSION "This corrosion could not have been caused by anything other than water getting into the engine through the fuel feed line," an expert witness yesterday told the Air Court of Inquiry into the crash of the Australian National Airways' flagship, Amana. on June 26, with the loss of 29 lives.
The witness is Charles Wilfred James Gibbs, of McKinnon road, McKinnon, Victoria, the chief engine specialist of the Department of Civil Aviation, who said that corrosion in No. 4 engine was evident in the bore of the rotor and part of the drive shaft of the No. 1 fuel pump. No. 1, 2 and 3 engines had been badly damaged as a result of the impact, he said, but No. 4 was not seriously affected by damage. The find ing of corrosion in the fuel feed passages would be the only indication why the engine was not operating properly. Using parts from one of the engines of the Amana and photo graphs, Briggs explained to the Court the damaged caused to the first three engines and showed the point at which the No. 4 en gine fuel flow meter was found to be corroded. The part at which corrosion had taken place -the fuel chamber of the meter between the recording vanes - was of aluminium alloy, he said. He told the Court that he had experience of corrosion and was familiar with the effects of it on aluminium alloys. Test On Metal Mr. L. D. Seaton, K.C. (assisting the court): Having re gard to the condition of the in strument when you first saw it, was there any method whereby water could have got into it from ex ternally apart from the fuel pipe? Witness: No. Gibbs said that it was his opinion that the water lodged in the position immediately the en gine came to rest. There had been water contact for some sub stantial time when he saw the engine. He carried out a test by placing a quantity of water in an uncorroded part, leaving it for eight weeks. When he returned, he found corrosion similar to that in No. 4 engine. He also cal culated how much rain would have entered the fuel line if it had been lying in an exposed position in the open and a total of 90 points of rain had fallen. Only 0.15 cubic inches would have fallen into the tube. George Albert Armfield, of Wellington-street, Inglewood, the chief engineer of Airlines (W.A.) Ltd. gave evidence of three Dove aircraft having been refuelled from a Vacuum Oil Co.. tanker on June 26 at Guildford before
the Amana was refuelled. He said that he had no report of any defective running from the planes. His engineers had drained the weatherheads. James Edward Schofield, of Boyle-street, Ashburton, Victoria, the acting-chief inspector of ac cidents for the Department of Civil Aviation, said that it would be possible for water to be re tained in a fuel system, but he could not say how much. He had heard of the experience re lated by Cuthbert Allan James Lum who said in evidence the previous day that he had encount ered water in the fuel of his air craft after 20 minutes' flying from Ceduna although he had drained the weatherheads of the plane be fore he took off. To Mr. Justice Simpson who, with the assistance of two asses sors, Capt. J. W. Bennett and Mr. D. B. Hudson, is conducting the inquiry: It was desirable, but not normal, to let some time elapse before draining the weatherheads in order to allow any water to sink to the bottom of the tanks. His department did not take the view that the draining of weather heads after refuelling was a waste of time. Mr. Justice Simpson said that he thought it would be a "rather frightening situation" to realise that after draining the weather heads there still might be some water in the tank. Witness: It is very frightening. Schofield said that the R.A.A.F. had been very perturbed about the matter, and after a recent accident had, as a temporary expedient, ordered that ropes should be tied to each wing of an aircraft and that it should be rocked before draining after refuelling. Asymmetric Flight From departmental reports, the witness said that Capt. Chapple of the Amana had undergone his last asymmetric test flight on a DC4 in 1948, when he started piloting that type of aircraft. His subse quent tests were on DC3 planes. Mr. Justice Simpson asked him whether he considered it satisfac tory to the department as the pilot had been engaged on DC4 aircraft in his course of duty. Witness said that he considered it was satisfactory, as a test on a DC3 would be more difficult. Under such a test a pilot was required to fly with one engine cut so that, in flying a DC4, he would have three engines running, but in a DC3-a twin-engined aircraft-he would have to oper ate on one engine.