It's not to defend their country, as half the crew aboard Spirit of Mateship have done countless times in their previous postings, but to challenge and reward themselves by taking on one of off-shore racing's pinnacle events - the Sydney to Hobart.
Army firefighter Lance Corporal Prue Sanson injured herself on the job in Queensland, and has been in rehabilitation programs to mend. And while she is physically recovering, the blue water classic is helping her emotional recovery.
"Once you start getting back into full duties there is a little bit of angst. This has cured that," she says. "If I can do this I can do anything."
But the challenge is still daunting.
"The more we know about Bass straight the nerves start kicking in a bit."
Sydney to Hobart Yacht Race: Behind the scenes
The crew competing aboard Spirit of Mateship is split one-to-one with professional sailors, and past and present defence personnel. Of those veterans many suffer physical and unseen wounds from combat and they are using the 628 nautical mile journey down south to heal some scars.
"This is fun stress. Stuff you can deal with," says Craig McCarthy, a retired army and navy veteran with more than 26 years experience.
"The other stuff you can't deal with it and it catches up with you later. And a lot of guys are having those troubles."
McCarthy is honest about the challenges facing returning soldiers who have served in war zones. He, like others on board, has been diagnosed with post traumatic stress disorder.
"It was sort of an accumulation of things after 26 years. It sort of caught up with me all at once," says Mr McCarthy. "I have been dealing with that and doing this has been a big help."
"I lost a mate two weeks ago from suicide. If he had a chance to do something like this maybe it would have been different."
Each Hobart race is unique, so too is every veteran's return to civilian life. But the skipper aboard the Mates4Mates program believes initiatives like the Spirit of Mateship are an excellent way to assist returning service personnel.
"For a lot of them it is a cathartic experience...They do a lot for their country and if we can help them it is a very satisfying thing," skipper Russell McCart says.
It is a small but important gesture for those who daily faced the prospect of making the ultimate sacrifice.
