Mistakes were fixed, says Alan Joyce.

Mistakes were fixed, says Alan Joyce. Photo: Louise Kennerley

The aircraft engineers' union has alleged a litany of errors on Qantas aircraft sent for heavy maintenance in Asia over the years, including a Boeing 747 that did not have three of its four engines attached properly.

The extraordinary attack on maintenance practices in Asia, and against Qantas' decision to have work carried out there, was made during a Senate inquiry into the airline's future, two weeks after it confirmed it will axe 5000 jobs as part of a $2 billion cost-cutting program.

In a bid to stop the government from relaxing the Qantas Sale Act, Australian Licensed Aircraft Engineers Association federal secretary Steve Purvinas has used parliamentary privilege to release a dossier detailing multiple errors on Qantas planes following heavy maintenance in Singapore, Hong Kong and Kuala Lumpur.

His claims come after a week in which the spotlight has been thrown on the competency of aviation officials in Malaysia following the disappearance of a Malaysia Airlines passenger jet with 239 people on board.

Mr Purvinas released a submission claiming no less than 600 defects on the first Qantas 737 to have work conducted on it in Singapore in late 2009. The alleged defects included corrosion on the wings, a cracked floor beam, damaged wiring, and numerous wiring clamps loose or damaged.

Mr Purvinas said the Australian travelling public was put at risk by Qantas management's decision to offshore more work - a claim rejected by the airline.

He has also alleged a Qantas 747 jumbo that had heavy maintenance in Hong Kong in 2008 was later found to have three of its four engines ''not held on properly''.

The union has also claimed that at least 95 errors were found on a Qantas 737 which in 2008 had heavy maintenance in Kuala Lumpur. They included ''extensive corrosion on the fuselage, doors and wings'', and rusty flight control cables.

But Qantas chief executive Alan Joyce told the Senate inquiry every Qantas plane that had maintenance performed on it was certified not only by local regulators but Australia's Civil Aviation Safety Authority. He said any mistakes were fixed when found, and the level of errors that occurred at offshore maintenance bases was no greater than those made here.

A spokeswoman for Transport Minister Warren Truss said the air-safety watchdog had been in discussions with Qantas to ensure any new arrangements did not impact on safety.

Meanwhile on Friday, John Holland Aviation Services revealed it would reduce maintenance operations, blaming current market conditions. The company did not say how many jobs were at risk, but the Australian Manufacturing Workers Union said 230 airline maintenance positions were set to go, including 150 jobs at Tullamarine.

With AAP