The increasing outsourcing of aircraft maintenance is leading to lower industry standards, according to the Aircraft Engineers International (AEI).
Fred Bruggeman, AEI general secretary, speaking at the AEI's 39th Annual Congress in Istanbul, said: "Unfortunately it is a cause for concern that licensed aircraft maintenance engineer unions and associations around the world are increasingly having to fight tooth and nail to maintain the bare minimum acceptable levels of safety and standards.
"Some of the evidence presented to delegates highlighting outsourcing shortcomings was truly shocking."
Other concerns raised included the non-reporting of defects and the willingness of unqualified personnel to sign off defects.
"The concern here is the safety chain, which is already stretched by outsourcing, will snap if there is any further dumbing down of the aircraft engineer's supervisory role," added Bruggeman.