Hundreds of travellers have been left stranded at Sydney Airport after more than 50 flights were cancelled on Friday (February 14) due to an unexpected air traffic controller shortage.

Airsevices Australia, a government agency, was forced to reduce aircraft movement due to poor weather, but the delays were made much worse by one air traffic controller calling in sick on short notice, it has been reported.

This has caused 26 departures and 32 arrivals to be axed. Most of the passengers will now have to fly on Saturday.

As a result, airlines were left scrambling to notify passengers, many of whom were made aware of delays just before boarding.

This comes amid a day of public transport chaos in Sydney, with lengthy delays across the train network, which has been crippled by ongoing industrial action.

According to FlightRadar24, as of 10.30 am GMT (9.30 pm AEDT) many flight arrivals continue to be cancelled and delayed, though departures are now mostly back on track.

In a statement to 7NEWS, Airservices Australia said: “We have since sourced replacement staff to fill the position, however in the interim some flight cancellations did occur.

“We are disappointed that this has occurred so soon after our strong performance over the Christmas period, when ground delays were at record lows across the network.”

Since then, buses in the Sydney central business district have been under increased pressure from the backlog of stranded passengers and those using public transport have been advised to expect delays.

Anton Radchenko, CEO of AirAdvisor, explained: “It looks like a combination of poor weather and from what we gather, a single member of staff calling in sick has caused complete chaos at Sydney Airport.

“If reports emerging from Australia are accurate and the situation at Sydney Airport has at least in part been caused by one staff member being unable to attend work – then serious questions have to be asked of the airport’s contingency planning for occurrences like these.

“It’s likely thousands of passengers travelling to and from the airport today are likely to have been hugely inconvenienced by the disruption.

“Right now, it’s entirely possible that other services in and out of Australia will be affected. Multiple flights being disrupted can have a damaging ripple effect on other services, as one flight missing its departure slot can force other flights to take off later than planned.”

The expert, from flight compensation company AirAdvisor, added: “If your flight is operated by a UK or European airline departing from the UK or EU to Sydney [and from Sydney to the EU], you might be eligible for up £520 / €600 (920 AUD) of compensation.

“In the worst case scenario, when a flight is cancelled, you are entitled to request a ticket on a new flight to your destination, at your intended airline’s expense. If your airline can’t rebook you within a reasonable amount of time, then they must find an alternate flight even if this is with a different airline.

“As a general rule, if your travels take you to the EU or the UK, then you can benefit from some of the best air passenger rights and protections in the world with the UK’s 261 and the European Union’s EU 261/2004 regulations.”