A plane was diverted over concerns about an electronic cigarette.

The diversion will have cost Air New Zealand a considerable sum of money.

The flight from Tauranga to Wellington flight never made its destination after reports of an electrical smell in the cabin. It was diverted to Palmerston North.

According to news website www.tvnz.co.nz an Air NZ spokeswoman told Fairfax the flight was diverted after an electrical smell wafted through the cabin. 

She said: "The cause of the smell has since been identified as an electronic cigarette that a customer had forgotten to switch off as is required under our in-flight safety procedures.” 

Emergency services were called to the incident and firefighters checked out the plane.  

Passengers were offered transport from Palmerston North to Wellington by bus. 

* AvSax fire containment bags are now on board several major airlines worldwide. 

They have been deployed on aircraft 20 times so far this year and means they don’t need to make an emergency landing and can continue the flight confident the bag has solved the problem. The average cost of an emergency diversion in the USA is $400,000. 

If an electronic device starts to seriously overheat or emit smoke the cabin crew will pour at least two litres of water into an AvSax and then drop the burning device into the bag, adding additional water as required. The water activates the polymer gel inside the bag causing it to expand around the device. Should the device keep on venting then the AvSax is tough enough to absorb the force. 

The AvSax cools the batteries in the device, reducing the likelihood of the battery catching fire but if it does go into what is known as thermal runaway when all the battery cells catch fire at incredibly hot temperatures it is all contained within the bag.

Amazingly, the water is absorbed into the internal lining of the bag so the device is dry when it is removed.