Air New Zealand has grounded its Eagle Air regional operations after hairline cracks were found in the tail area of a Beech 1900D turboprop during routine maintenance.
Engineers are now inspecting the carrier's fleet of 19 Beech 1900D aircraft. Of the four aircraft inspected so far, three were found to have similar cracks.
An Air New Zealand spokeswoman adds that the cracks were discovered in the tail area near the vertical stabiliser of the aircraft and that there is currently "no information on the cause".
No further details are available.
The 19-seater aircraft have been in service with Eagle Air since October 2001, and have an average age of 10.5 years.
Eagle Air services have thus been cancelled as a "precautionary measure", while checks across the fleet are being conducted, says its general manager Carrie Hurihanganui.
"We apologise to customers for the inevitable inconvenience caused by undertaking a full check of our fleet. However, the safety of our customers, our staff and our aircraft is paramount and non-negotiable for the airline," she adds.
The carrier will utilise aircraft from Air New Zealand's fleet to make alternative arrangements for the 800 affected passengers.
Eagle Air is a regional subsidiary of Air New Zealand and operates services to 20 destinations around New Zealand.