Nigeria’s domestic carrier, First Nation Airways, has suspended operations six months after its resumption in September, 2016.
The airline last year suspended operations for three weeks when the two aircraft in its fleet had to go for maintenance.
According to reports, the airline’s technical crew had to go for simulator training while the two aircraft in its fleet have to be taken out for maintenance.
The two aircraft must be airworthy before the airline would be allowed to operate again because, according to regulation, schedule flight airlines must operate with a minimum of two aircraft.

Source; http://www.legendvibes.com.ng/2017/03/again-first-nation-airways-ncaa.html?m=1