A Jetstar flight attendant has been injured after a second near-collision between two planes at Sydney Airport in as many weeks, but experts say the latest is likely not related to current air-traffic control shortages.

Jetstar flight JQ402 was preparing for takeoff from Sydney to the Gold Coast about 7.15am on Sunday when its pilot “slammed the brakes” to avoid a Qatar Airways Boeing 777, being towed by a tug.

The incident comes after a near-miss between two Qantas planes at Sydney Airport on July 27, which saw one aircraft forced to take evasive action to avoid the potential catastrophe.

But an aviation source said despite the two near-misses and heightened focus on air traffic control numbers, they believed the incidents were likely not related.

“It’s a really big issue, but it’s very easy to try and conflate the staffing issues with these two incidents,” the source said.

“The one (the other) week was an issue by the air-traffic controller.”

The Australian Transport Safety Bureau said damage to the connection between the Qatar Airways flight and the tug would be looked at as part of the investigation into the incident.

“The ATSB will collect available data from both aircraft, and air traffic control,” they said.

“Investigators will also interview the involved flight crew, tug operators and air traffic controllers, plus other witnesses and involved parties, and collect relevant recorded information including CCTV footage.”

In a statement, Jetstar said its aircraft had been “following instructions” when the pilots were forced to “brake firmly” to avoid an incident.

“Our aircraft was following instructions by air traffic control when the pilots were forced to brake firmly after another aircraft came in close proximity,” the low-cost carrier said in a statement.

“We have commenced an investigation into the incident.”

The incident between the two planes lit up social media within minutes of it occurring.

“Holy f**k… this was seriously close,” passenger Rod Hockey posted on Facebook.

“Saw my life flash before my eyes just now”.

In a video posted to social media, the Jetstar pilot informed passengers of the situation immediately after it occurred and told those onboard the Qatar Airways flight had broken its towing equipment.

“With the sudden stop we have had a situation where one of our cabin crew has been injured,” the pilot could be heard to say.

“The situation there is that they said they didn’t follow instructions, we were told to hold short and we were focused on crossing a runway, so only by chance that at the last minute we were able to stop.”

According to the Australian Transport Safety Bureau, one rear flight attendant onboard the Jetstar JQ402 plane sustained a broken wrist.

The Jetstar flight was cancelled and the aircraft returned to its gate, with passengers booked onto later departures out of Sydney.

NSW Premier Chris Minns described the second near-miss in two weeks as “concerning”.