On 12 April 2013, an Airbus A319 landed without clearance on a runway temporarily closed for routine inspection after failing to check in with TWR following acceptance of the corresponding frequency change. Two vehicles on the runway saw the aircraft approaching on short final and successfully vacated. The Investigation concluded that the communication failure was attributable entirely to the Check Captain who was in command of the flight involved and was acting as 'Pilot Monitoring'. It was considered that the error was probably attributable to the effects of operating through the early hours during which human alertness is usually reduced.