The legendary McCaw became a commercial helicopter pilot after ending his illustrious rugby career following the All Blacks' World Cup triumph last year.
McCaw has been ferrying rescue teams Kaikoura, close to the epicentre of a quake which struck early on Tuesday morning, where people have been stranded due to landslides.
He told the New Zealand Herald: "We took the Fire Service just north and south of Kaikoura to check out all the slips and make sure everyone was accounted for."
McCaw revealed he saw, "big cracks in the road, cracks in the side of the hills, and obviously slips".
He added: "At one point, the railway was way out over the sea - it had been pushed out by slips. It would not have been a nice place to be at midnight last night."
McCaw said of his experience of when the quake hit: "Like everyone else, I got woken up at midnight... yeah a bit scary."