Around 40 Kiwis a year volunteer — from tradies to deck and engineering officers, surgical staff, physios and for general roles like cooks, hairdressers and IT staff — for weeks, months or even years at a time.
The ship is about the size of an inter island ferry – with an international crew of 450 – all dedicated to providing essential surgery for people living in abject poverty in West Africa.
Thanks to Africa Mercy, more than 1500 free surgical interventions and 8000 dental treatments are provided annually to people who find themselves ostracised through a lack of access to this otherwise.
"A team goes into the country two years prior and line up surgeries to do, mostly congenital defects, which get more serious as they get older. And because of their culture they get ostracised and end up on the streets," says Sinclair.
"The before-and-after surgery photos are fantastic. You just have to feel how incredibly lucky we are here."
Kathy says she knows to expect some heart wrenching sights.
"When preparing to go, there's the logistics, but the other side is the emotion and I don't know if you can prepare.
"We recognise we've been very privileged in life and want to give back while we're still fit and healthy. I think it's going to be a life-changing experience for us."
Sharon Walls of Mercy Ships New Zealand says five billion people worldwide do not have adequate access to required surgical interventions.
"We spend 10 months each year providing essential surgery, alongside mentoring and training for the local healthcare to help build their nation's medical capacity," she says.
The charity is founded on Christian values, and volunteers that belong to church groups are often given the financial support of their church.
Kathy and Sinclair are having to self-fund everything including their live aboard costs, vaccinations and more than $10,000 in airfares alone. They have not instigated any fundraising but say they would be grateful to anyone wishing to give any donation towards costs.
"We were quite shocked at the cost of the inoculations," says Sinclair. "We've had cholera, rabies, polio, typhoid, TB, and these have cost us over $1500 in injections.
"We're like pin cushions."
The couple has set up their lifestyle in Whangamatā to spend several months of the year travelling - adventures eagerly followed by friends via Kathy's travel blog.
They have a bus that Sinclair has renovated, which they intend to ship overseas for another of their annual adventures following the Mercy Ships voyage.
"But we've come to the part of our life where we want to give back. We're not religious, we've just got the same values as those onboard this trip," says Kathy. "They want to help people, and our values are right up there the same.
"It's all for the people."
