Qantas has apologised to about 250 passengers who were stuck on the tarmac in Sydney for four-and-a-half hours on Monday afternoon while the airline dealt with multiple separate aircraft issues.

Flight QF43 to Denpasar had been scheduled to leave at 4.20pm yesterday.

A passenger on the flight called ABC Radio Sydney last night, after four hours of waiting on the tarmac, saying:

They’ve come back with multiple messages and they’ve constantly been changing throughout, the time frame, to the point where a lot of people are not really sure now what’s going on and what is the truth and are we actually going to get off the ground? But there’s been some engineers in and out for hours trying to work out what’s going on with the plane, and now we’re just being told they’re about to shut the computers down and reboot them.

A Qantas spokesperson told Guardian Australia that the flight was delayed initially due to a refuelling issue but then engineers identified a separate issue that required assessment and resulted in further delays.

The spokesperson said:

We understand this was a frustrating experience for our customers and sincerely apologise for this inconvenience. We’re reviewing this incident and acknowledge that our communication could have been better in this instance.

The flight departed for Denpasar at 8.50pm.