The yacht master, David Mitchell, who has not been arrested or charged in relation to the 2017 drug importation plot, spent a third day on Wednesday giving evidence during Mr Lembke's trial in Newcastle District Court.

The prosecution alleges one of the drug syndicate members, who cannot be identified, met Mr Lembke in September, 2017, and the Newcastle musician agreed to sail the drugs from Tahiti.

Police boarded the boat at Toronto on November 15, 2017, found the 700 bricks of cocaine on board and arrested Mr Lembke and two drug syndicate members, who cannot be identified.

Mr Lembke, 49, of Mayfield East, and West Australian co-accused Daniel Percy, 36, have pleaded not guilty to importing a commercial quantity of cocaine.

Mr Lembke claims he did not know the cocaine was hidden in the twin hulls of the 13-metre catamaran Skarabej. Mr Percy is accused of organising the catamaran for the drug shipment but denies knowing the cocaine was on board.

Under cross-examination from Public Defender Peter Krisenthal, who represents Mr Lembke, Mr Mitchell was shown an email exchange between Mr Mitchell and a woman from the days after the police raid that had the subject line: "half a tonne?"

"There were a couple of things that worried me with the communication," Mr Mitchell wrote to the woman. "So I looked over the boat carefully and checked the water line and even swam under it in Bora Bora but it all seemed in order. "There was no way to know."

Mr Krisenthal suggested to Mr Mitchell that, after arriving at Lake Macquarie and before the police raid, Mr Lembke told him that one of the syndicate members had approached him and said he had "good news and bad news". Mr Krisenthal suggested Mr Lembke told Mr Mitchell that the syndicate member was going to pay Mr Lembke $500,000 but he had to do another job relating to the Skarabej.

Mr Mitchell said he couldn't recall the conversation but said it "could be possible I wiped it from my memory".

Meanwhile, the syndicate member who claims he enlisted Mr Lembke's help began giving evidence on Wednesday.

He told the jury he incurred a massive debt gambling in Hong Kong, began selling encrypted phones and then was told he "needed to find somebody who could pilot a boat".

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