"We've found it's potentially a great benefit. We're looking at it as a back-up for the wet crew as opposed to a primary tool for search and rescue."
Tony Unwin, who owns Tauranga-based Gyrate, said a gyro's running costs were about 10 per cent of a helicopter's.
"Gyros are more simple, have a safer design and are less complicated to fly."
But the two-seat aircraft was unable to lift loads.
"We've been searching for lost kayaks and people in the water in a practice environment," said Mr Unwin.
"I approached them [Tauranga Volunteer Coastguard] last year. We're the main agent for modern gyroplanes in New Zealand. As I want to market gyroplanes, that's part of the approach. They can be used for search, pipeline and power line survey - all things traditionally done by helicopters."
Mr Unwin said he provided gyro pilots on a volunteer basis, and the Coastguard's only expense was fuel and maintenance.
The national Coastguard's communications manager confirmed Tauranga was the only location in the country testing the gyro.
Tauranga Coastguard board chairman Chris Phillips said his organisation could not hire helicopters or planes because that was a police responsibility.
Running costs for a gyrocopter were $65 an hour (plus GST), while a helicopter could cost $1500-$2000 per hour.
The gyro also cut the time a boat has to spend in the water - at a running cost of $280 per hour (plus GST), he said.
The latest gyro exercise happened last Sunday, and Mr Phillips said he hoped the aircraft would become fully operational as a search tool in the next few months.
NZ Coastguard chief executive Patrick Holmes said the gyro was being considered as part of a wider review to determine how the charity could best deliver services.
"It's being trialled as a research and development project. There's a project in Canterbury looking at unmanned aerial vehicles, too."
Mr Holmes refused to reveal the amount of the national organisation's air operations budget, calling it "commercially sensitive information."
The national operating budget, which came from sources such as lottery grants ($2.3 million) and donations, totalled more than $7.3 million last financial year. Tauranga Volunteer Coastguard relies almost entirely on donations, grants and other fundraising activities to secure its $300,000 yearly operating budget.