Air New Zealand says it now expects to make a first-half loss of about $30 million to $55 million, before tax.

It's just provided a trading update to the NZX.

The national carrier says it expected a two to three percent uplift in revenue across domestic and US-bound bookings.

However, this hasn't materialised and isn't evidenced in future bookings.

NZ Shareholders Association head Oliver Mander says the engine issues and ongoing economic downturn are the main factors behind these changes. 

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