Safety system not working in Qantas A330 close call near Adelaide AIR Safety investigators have revealed that the traffic collision avoidance system in one of two Qantas Airbus A330s which came too close to each other near Adelaide last month was not working. An Australian Transport safety Bureau report confirmed, as revealed in The Australian, that the aircraft were not in danger of colliding when the traffic collision avoidance system of one aircraft issued an alert, called a resolution advisory, which gives pilots instructions they are required to follow. Aircraft VH-EBO was travelling from Sydney to Perth at 38,000ft on September 20 and the VH-EBS was travelling from Perth to Sydney at 39,000ft when the crew of EBO was cleared by an air traffic controller to climb to 40,000ft. "Soon after, the controller cancelled the clearance and the aircraft descended back to FL 380 (38,000ft)," the report said. The flight crew of EBS received a resolution advisory alert from their aircraft's traffic collision avoidance system. However, EBO's flight crew advised that they did not receive any indications on their traffic collision avoidance system of the presence of EBS. A full system test conducted on EBO's traffic collision avoidance system after the incident confirmed it was not functioning. Investigators said recorded data from the two aircraft showed that the minimum vertical separation was 650ft when the two aircraft were 4.1 nautical miles (8 km) apart laterally. The lateral separation got as low as 1.6 nm (3 km) when the aircraft were 870ft apart vertically but by then they were moving away from each other and the correct separation of 1000ft vertically and 5nm horizontally was established shortly afterwards. The ATSB investigation will continue to analyse the recorded data, the context in which the air traffic controller made his decision as well as examine the traffic collision avoidance system and its reliability. Qantas said the ATSB's report demonstrated its pilots acted appropriately and that the planes were on diverging one-way routes that were never going to intersect. "The incident demonstrates the effectiveness of multiple layers of protection and redundancy built into aviation safety in Australia through safety regulations, air traffic control, aircraft systems, and the training of pilots," a spokesman said. While the TCAS system on one aircraft was working intermittently it was working when the aircraft departed this wasn't a contributing factor to the incident.