Airways Corporation is engaging an Australian consultant to help investigate why the runway lights at Auckland international airport failed last weekend.
Twenty two flights were diverted or cancelled when the lights stopped working.
An independent consultant who is an expert in airport lighting, is due to arrive on Monday.
A member of the Canterbury University School of Engineering is also being engaged.
Christchurch and Wellington airports will be examined as part of the investigation.
Airways operations manager Lewis Jenkins says the failure is believed to be the first of its kind for the agency in 25 years.
He says the wiring reached heats of more than 2000 degrees, melting sand used for insulation.
The section of cabling is now being examined in Wellington.