A navy damage control team has boarded a burning ocean-going tug off Northland hours after the crew abandoned ship when fire broke out in the engine room.

The last of seven new Navy ships will arrive in Auckland tomorrow, at least two years late, and following a troubled maiden voyage from the ship builder's yard in Australia.

"Bugger," a senior official exclaimed. "Well at least the Aussies will be paying for the repair."

EXCLUSIVE: Robotic "drone" spy planes flying by remote control could be used to patrol New Zealand's waters.

Depth of the sunken ferry Princess Ashika means the recovery of the 93 bodies trapped inside would be a prohibitively costly, lengthy and dangerous process.