Princely show from Sydney Harbour sailors

Dominica Sanda and Belinda Tasker

In wet, cold and choppy conditions Aussie veteran hopefuls have put on a princely sailing show on Sydney Harbour for Prince Harry.

The young royal, onboard an official support vessel, eagerly observed the sailing demonstration on Wednesday afternoon in torrential rain in preparation for the 2018 Invictus Games, before his vessel sidled up to them for a quick chat.

It was part of Prince Harry's two-day visit to the city to launch the 500-day countdown to the Games.

The sailors, who are war veterans, have every chance of catching up with the prince again next October as Invictus Games athletes, with sailing set to be introduced as a new sport in the Sydney Games.

Before heading out on the Harbour, the 32-year-old prince spent the morning chatting with other Invictus hopefuls encouraging them to keep training for both this year's Games in Toronto and then onto Sydney in 2018.

At Kirribilli's Admiralty House, Prince Harry told one small group: "I hope to see you all in Toronto and then you've got Sydney. You have to keep training."

Emma Kadziolka, a 28-year-old army nurse diagnosed with brain cancer and who is hoping for a spot in the Australian team competing in Toronto, described Harry as casual and relaxed after chatting to him about her Games preparations for indoor rowing, seated volleyball, shot-put and discus.

"He asked about the events I'm involved in and said good luck for the Games," the Brisbane-based nurse told AAP.

"Him being here has helped give a certain buzz to the team at the moment."

Jamie Tanner, a 34-year-old former army corporal from Ballina in northern NSW, who hopes to compete in wheelchair tennis, rugby and basketball, spoke with the prince about how the Games was a good opportunity for veterans to reconnect with their military family and how adaptive sport can help with their recovery.

"The Games are hugely important not just for us as athletes but also for society," said Mr Tanner, who spent 11 years in the army and served in Afghanistan, Iraq and East Timor.

After the sailing demonstration, the royal was due to do a walkabout at Circular Quay before watching demonstrations of adaptive sports by the Australian Invictus squad.