Carriers attending the Dubai Airshow are optimistic about the Boeing 737 MAX's eventual return to service and confident in the aircraft.
Boeing announced on Tuesday an order from Air Astana for 30 737 MAX planes worth $3.6 billion.
Air Astana is a low-cost airline in the Republic of Kazakhstan.
Another airline, which has not been identified, has reportedly signed a firm order for 10 Boeing 737 MAX 7 and 10 Boeing MAX 10 jets, a person familiar told Reuters.
That would bring Boeing orders so far at the show to $5-6 billion.
This comes a day after announcing an order from Turkey's SunExpress.
The Boeing jet has been grounded since March after two fatal accidents.
The aircraft maker has been modifying software and conducting pilot retraining in order to get regulatory approval to return the 737 Max to service.
Boeing has been looking at the end of the year to return the 737 MAX to service in the United States.
In Europe, it may take until the first quarter of 2020.
Southwest and American Airlines extended Boeing 737 MAX cancellations until March.