In spite of publicity claiming there are now hordes of people jumping on yachts to cruise the world's oceans, it is still far from crowded out there, says Eric Gray.

Eric and Cathy Gray have just returned to Tauranga after a 10-year voyage that's taken them across three of the world's oceans; the Indian, Atlantic, Pacific and places in between.

The Grays designed and built their boat, a 12m cutter rigged yacht, with ocean voyaging in mind.

It's overbuilt compared to many modern hulls, which Cathy says is comforting if they fall off a wave, because they don't have to worry about cracking the hull – as some fibre glassed yachts can do.

Eric says it was only as they waited for the weather window for their last ocean passage from Tonga that he realised just how well Erica has behaved for them.

They were anchored at the Minerva Reef with 24 other boats, and people on the other boats were dealing with boat issues, little problems that need fixing.

'And that was when I realised how few problems we have had,” says Eric.

They did have a couple of issues with the gearbox spline. They were heading into a Malaysian marina when the propeller stopped. Surrounded by expensive foreign boats, they glided into a vacant berth where they were able to await a new part.

The second time was half a world away at Mayaguana Island in the Bahamas. They had just made it through the coral reef passage, they dropped anchor and waited a month for another part.

They bought a new gearbox when they reached the United States. But apart from a few minor additions like a cockpit table, solar panels and an additional sail, Erica is the same boat that left Tauranga in 2006.

And the Automatic Identification System, they swear by it. AIS is a automatic tracking system used on ships and by vessel traffic services for identifying and locating vessels by electronically exchanging data with other nearby ships, AIS base stations, and satellites.

It is invaluable in shipping lanes, because all commercial shipping has to have it and it shows the small yacht on the screen of the large cargo ship with the yacht's name and course data.

On the Intracoastal Waterway – which is 3000 miles inland along the Atlantic and Gulf of Mexico coasts of the United States – early one morning the AIS showed a tug coming through. It was probably moving a barge and the information from the AIS meant Eric could wait until it passed before he stuck his nose out.

At the Panama Canal, waiting for clearance to use locks, they could use the AIS information to tell when a request to move was likely to be approved.

'Singapore Strait, when you make that jump to get across the strait, having AIS you know when to step,” says Cathy.

'I don't think you can get into Singapore now without AIS – or Thailand.”

It's still not perfect. The yacht version has a two-watt transmitter and the commercial shipping version has an eight-watt transmitter.

So the smaller yachts appear on the big ships AIS within a couple of miles, or about 5km. A good, solid radar reflector is still important, says Eric. But with AIS you have a ship's name and you can call them on Vhf.

People are already asking what their favourite place was, says Eric, and the answer is Planet Earth. There is one place they don't want to go back to, the island of Ferando De Noronha off the north eastern tip of Brazil.

Erica made landfall there after crossing the Atlantic from Namibia, to find they were charged $US128 for anchoring overnight.

Their next stop Devil's Island of Papillon fame was also rushed, for a different reason. Twenty minutes after arrival the gendarmes came alongside and told them to leave because they were launching two rockets from French Guiana that day, and they could return at 7.30pm.

There was an Ariane rocket and a Soyuz launch that day. They saw both rockets on their way and returned to the island in the evening.