New Delhi, Nov. 15 -- The US aviation system is slowly recovering after a nationwide flight shutdown on Friday. The Federal Aviation Administration (FAA) officials have blamed it on routine maintenance gone wrong.

The FAA had issued a nationwide ground stop that halted nearly all departing flights for almost five hours, marking the longest nationwide halt to air travel since the attacks of 11 September 2001.

No flights were allowed to take off from the continental US for more than four hours from 15:54 EST (19:54 GMT) on Friday. However, some international flights were permitted to depart US airports during the shutdown in an apparent effort to clear space.

Federal Aviation Administration head Bryan Bedford predicted on Saturday that o...