An investigation is underway in Australia after a pilot fell asleep in the cockpit and missed their destination by almost 50 kilometres.

They were the only person on board the small plane, which was flying from Devonport to King Island in Tasmania on November 8th.

Air traffic controllers were unable to contact the pilot in-flight.

Officials said the pilot travelled past the intended destination while the plane was flying on autopilot.

Ultimately, the pilot woke up, turned the aircraft around and was able to land safely at King Island.

There was no damage to the aircraft, and nobody was injured.

However, authorities say they are still regarding the incident as "serious", and the Australian Transport Safety Bureau is now investigating a "pilot incapacitation".

In a statement, flight operator Vortex Air said the flight was the 'adequately experienced' pilot's first after a period of leave.

The statement says: "Vortex Air takes the safety of our passengers, crew and pilots extremely seriously and always abide by all safety procedures.

"This is an extremely rare occurrence, as demonstrated by the companies’ excellent safety track record, and the company is providing the necessary support to the pilot to assist them to safely return to full duties."

The company adds that the investigation into the incident is ongoing.

Additional reporting by IRN