Guns left unattended on Australian airport baggage carousels are among issues outlined in a dossier of "highly concerning safety breaches" under scrutiny by regulators.
An undocumented box of petroleum products loaded onto an aircraft, passenger stairs wheeled away before the plane door was closed and collisions with refuelling hoses were detailed in memos sent to Swissport cargo workers in the past six months, the Transport Workers Union said on Tuesday.
Swissport is one of the companies Qantas outsourced its ground-handling work to in 2020, when it sacked about 1700 baggage handlers.
"This is urgent. We want the air safety regulator to investigate. We want to make sure our skies are safe," TWU secretary Michael Kaine said on Tuesday.
"We would rather sound the alarm than, in the event of a catastrophic event, be accused of remaining silent."
Swissport said it was disappointed the TWU was undermining the company's strong safety culture by distributing internal messages.
"We encourage and support all reporting of possible safety issues, regardless of whether those concerns ultimately prove to have no foundation, so we can learn from any incident," a Swissport spokesman said.
"That is indicative of a high-performing organisation, with a real commitment to safety."
It rejected a claim airside drivers were getting behind the wheel with four hours' training, saying recruits faced theory lessons, seven days of practical training and a final, formal assessment.
The regulator, Civil Aviation Safety Authority, said it had regular meetings with airlines' safety managers and had an active surveillance section that hadn't noticed an increasing trend in safety incidents at Qantas.
An industry-wide surveillance campaign was underway across airports and larger airline operators examining ground handling, dangerous goods and other matters.
"This is part of our normal campaign surveillance activities," a spokesperson said.
The union, which dubbed the memos a "dossier of highly concerning safety breaches", said understaffing was a key issue in the documents.
"The business is acutely aware our human resource levels are simply not at a sustainable level to meet the ongoing demand from the airlines," one reads.
Another notes "an increase of incidents where firearms have been incorrectly offloaded onto the arrival's carousel, rather than delivered to Baggage Services ... effectively allowing anyone to pick the item up and walk away".
A third mentioned a 350-kilogram discrepancy from the planned load for a Sydney-to-Brisbane Qantas flight.
The union's release follows an ABC Four Corners report on Monday detailing Qantas workers' concerns that the airline's reputation for safety is at risk.
In a statement, Qantas said it made tough decisions during the pandemic that were ultimately about ensuring the airline avoided the fate of numerous legacy carriers around the world, protecting many thousands of jobs.
The airline operated in one of the most closely scrutinised industries and would never compromise on safety, it said.
"It's worth noting that Four Corners did not contact the Civil Aviation Safety Authority regarding any claims made in the program," Qantas said.
"CASA has since reiterated that it has confidence that Qantas is operating safely."