The roll out of Thai Airways International's brand-new Airbus A350 XWB jets has been put on hold. The flag carrier had planned to debut the state-of-the-art aircraft on its Bangkok-Melbourne route as part of THAI's enhanced service. But Australian civil aviation authorities have kept THAI in the dark as to whether or when it will approve the airline's application to operate the airline to and from Australia. Authorities were cited as saying they were "unfamiliar" with this type of aircraft, especially on issues related to airworthiness. The aircraft received certification from the European Aviation Safety Agency in September 2014, with certification from the US Federal Aviation Administration coming two months later. <br/>