The 10 metre sloop, which was equipped with a life raft and a handheld VHF radio, was sailing from Vanuatu to Marsden Point on the east coast of Northland.
Search and Rescue Mission Coordinator Dave Wilson said the centre started the search at 6.15 am today, after a distress beacon from the yacht was activated.
Commercial vessel, the Norfolk Guardian, picked up van der Mespel this afternoon. The ship is due to arrive in Norfolk Island at 11.30pm tonight.
Earlier today, a New Zealand Defence Force C-130 Hercules aircraft was sent to the location of the beacon, and the Norfolk Guardian was diverted to the location.
The Hercules aircraft spotted the skipper of SV Waimanu waving from a life raft a few minutes after reaching the yacht's reported location.
"There is a strong 30 knot southerly wind blowing at the location of the life-raft, and the sea is rough with three metre swells," Wilson said.
Wilson said van der Mespel was sailing single-handed from Vanuatu to Marsden Point.
A survival pack with water, food and a note was dropped to the yachtsman.
Norfolk Island is about 1000km north of New Zealand.