Z Experimental Station

The Z Experimental Station (ZES), Cairns was set up in July 1942, jointly by Secret Intelligence Australia and the Inter-Allied Services Department. The building chosen to be the headquarters was known as "Fairview" (or House on the Hill), and it had been the ancestral home of the grandparents of Sir Charles Kingsford Smith.

As far as ISD was concerned it was used as a wireless relay station for the New Guinea Section. The site was selected by Commander Roy Kendall, the head of SIA and was about 3 miles (4.8 km) inland from the town of Cairns, North Queensland. The site was originally chosen for its good radio reception. There were, however, good security conditions for training, until the Cairns district became a very active assembly area for Australian and US troops operating in New Guinea.

Until June 42, ISD special operations personnel were trained at the Guerilla Warfare School, Foster, but this establishment in the south of Victoria had an extremely rugged climate, which continuously resulted in sickness on the part of operatives who had lived for many years in the tropics. Since ZES was the only ISD establishment outside the headquarters in Melbourne, it became a holding establishment as well as a training school. It was set up at a time when the town of Cairns was partly evacuated, and the area was isolated from the rest of Australia.

Owing to transport difficulties, many of the New Guinea operatives were delayed in Cairns after their training was completed for as much as 69 days. This worked both against security and against the morale of the operatives.

When the transport arrangements had been finalised, several operations staged out of the Z Experimental Station, including the famous Operation Jaywick raid into Singapore Harbour. This was due to Cairns' proximity to the islands in the South West Pacific Area. The Jaywick party departed Cairns near midnight 9 August 1943 in the MV Krait and sailed along the northern coast before reaching Potshot in North Western Australia which was the departure point for the Jaywick mission.

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