Qantas aircraft takes off with stranded passengers onboard

A recovery flight deployed from Sydney to pick up Qantas passengers stranded in the eastern European nation of Azerbaijan finally took off from Baku at 06:27am +04 (01:27am AEDT) local time en route to London, according to flight tracking website FlightRadar24.

It was originally scheduled to depart at 05:05am local time. The late departure means it will arrive in London at 07:50am local time instead of 06:30am. The relief flight code is QFA1D with A1D likely standing for aid.

The original flight QF1 en route to London Heathrow from Singapore made an emergency landing at Heydar Aliyev International Airport at approximately 2.15pm AEDT after a signal in the cockpit that intermittently alerted the pilots to the potential of smoke in the cargo hold.

Qantas said no evidence of fumes was found and it was likely "a suspected faulty sensor in the cargo hold".

Qantas made arrangements for the stranded passengers to stay at the Marriott Hotel in Baku while they waited for their recovery plane to arrive from Sydney.

A Qantas staff reportedly explained to passengers at hotel that the delay of the replacement plane and their pickup was due to airspace permissions with multiple countries for the unscheduled non-stop flight path to Baku and and was further complicated by the curfew cut-off time and Border Force staff strikes at Heathrow Airport in London.

The replacement A380 aircraft QFA6025 left Sydney at 11:40am AEDT on Saturday and landed in Baku at 21:15 +4 local time (04:15AEDT) after flying non-stop for 16 hours and 35 minutes. The crew had mandatory rest period for today's flight to London.

The average flight duration from Baku, Azerbaijan to London, United Kingdom is approximately 5 hours.

Qantas engineers from Sydney and London, including Airbus consultants have starting inspecting the other aircraft in Azerbaijan to make sure it is safe to fly.