Norwegian Air's shares fell sharply today as investors worried over weaker-than-expected passenger income and the potential impact of the crash of an Ethiopian Air Boeing 737 MAX 8 passenger jet. 

While Norwegian said its 'MAX' aircraft fleet remained in operation, China's aviation regulator grounded nearly 100 similar jets operated by the country's airlines.  

Norwegian Air had 18 'MAX' jets in its fleet of 164 aircraft at the end of 2018.

It is expected to take delivery of dozens more in coming years, taking the total to more than 70 by the end of 2021, the company has said in recent announcements. 

The move by China, and the possibility the ban could spread to other countries, was the main point to focus on for investors. 

Ethiopia also halted the use of the 'MAX', as did Cayman Airways, even though aircraft maker Boeing BA.N said it saw no need to change its guidance for use of the plane. 

Norwegian's shares fell 8.2% in early trade before a partial recovery to close 6.9% lower. 

The Oslo-based carrier has raised 3 billion Norwegian crowns ($345m) from shareholders in recent months and said it would cut costs and curb its rapid growth to regain profitability.

Norwegian, which has bet heavily on the transatlantic market, last week completed a share issue first announced in January, and said demand had exceeded its sale by 110% as the deep discount on offer attracted investors. 

"With a stronger financial position and lower cost going forward, we are well positioned to continue to attract new customers, not least in the long-haul market," chief executive Bjoern Kjos said. 

Norwegian's yield, a measure of revenue per passenger carried and kilometres flown, grew to 0.32 Norwegian crowns from 0.31 crowns a year earlier, while a Reuters poll expected a rise to 0.33 crowns. 

Its capacity expansion, as measured by available seat kilometres (ASK), peaked at 51% growth year-on-year last June but has since declined, hitting 15% in February, less than the 19.2% that analysts forecast.

Load factor, a measure of how many seats are sold on each flight, fell to 81.5% for the month, beating a forecast of 80.6% but down from 84.3% a year earlier. 

In a further boost to its profits and balance sheet, Norwegian said its fuel hedge contracts had so far this year resulted in gains of 917 million Norwegian crowns, partly reversing losses sustained last year. 

Aer Lingus and British Airways owner IAG, which in 2018 attempted to buy Norwegian, last week said it would not rule out another bid but added that it was unlikely.