The captain of an Air New Zealand flight reportedly locked his first officer out of the cockpit for two minutes in a "frightening" mid-air incident.
The incident occurred on flight NZ176 between Perth and Auckland on 21 May.
There had reportedly been some tension between the pilots after a 13-minute delay to the flight's departure after the first officer was asked to take part in a random drug and alcohol test.
According to the Daily Telegraph, Air New Zealand's manager of operational integrity and safety, Errol Burtenshaw, told AFP in a statement: "This departure delay frustrated the captain who prides himself on operational efficiency."
The first officer at one point took a break and had a coffee with a cabin crew member in the galley area.
When he tried to return, three calls to the captain over two minutes to let him in went unanswered.
Burtenshaw, said: "The captain did not respond or open the door because he was approaching a navigational waypoint and in his cockpit monitor saw a cabin crew member rather than the first officer ringing.
"The first officer became concerned that the captain did not answer the calls and used an alternative entry method to gain access."
Speaking to the NZ Herald, Burtenshaw said: "Naturally, cabin crew operating the flight were concerned about the inability to contact the captain and became quite anxious."
The captain was stood down for two weeks, and the first officer for one week following the incident.
According to the Daily Mail, the incident has prompted fresh calls for three people to be inside the cockpit during flights.
The disappearance of flight MH370 recently also raised the issue.
Aviation commentator Peter Clark said that no one should be left alone in the cockpit even for a small amount of time.
He said: "Two minutes is an eternity when people reflect on MH370. The transponder can be turned off, the flight co-ordinates changed, the plane depressurised."
Burtenshaw added that the airline had conducted an investigation into the incident and a report had been sent to aviation authorities.
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