Air New Zealand is starting to take a closer look at people's carry on luggage. 

The airline allows bags of up to 7 kg and 118 centimetres in length into an aircraft's cabin. 

If it's bigger than that passengers will be told to check it in, and if necessary, pay for the privilege. 

General Manager of Airports Kate Boyer says told Mike Hosking that they have noticed more people pushing the limits. 

She says it slows down passengers and impacts space on board. 

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