* Trouble with Boeing’s MAX may add NOK 500 mln to cost

* Q1 loss NOK 1.49 bln vs forecast loss 1.65 bln

* Has postponed aircraft deliveries from Airbus, Boeing (Adds cost forecast, bullets)

By Victoria Klesty and Terje Solsvik

OSLO, April 25 (Reuters) – Norwegian Air said the grounding of its fleet of Boeing 737 MAX aircraft may scupper the carrier’s plan to return to profitability this year, while posting a wider first-quarter loss on Thursday.

“Due to the uncertainty related to the MAX grounding, the company sees increased risk related to the target of a positive net profit in 2019,” Norwegian said.

The firm’s fleet of 18 MAX planes has been forbidden from flying following the deadly crash of an Ethiopian jet