A problem with safety rules might have put planes landing at Australia's Melbourne Airport at a higher risk of mid-air collision over the last two years.
ABC News reported that government-owned air traffic operator Airservices Australia (AA), which manages Australian airspace, has admitted that there have been instances where pilots were allowed to land on intersecting runways at Tullamarine when winds were too high.
AA was questioned about this problem by independent senator Nick Xenophon during a Senate hearing in Canberra.
Melbourne Airport had changed its rules two years ago when airports were allowed to land on the second, intersecting runway despite winds exceeding normal limits.
Melbourne is one of the three airports in Australia that allow the concurrent operations of intersecting runways. While the practice is banned in most countries, Australia, the US and Canada permit the operations of such runways.
However, there are strict conditions regarding when a pilot should be allowed to land on an intersecting runway that is in use. One such condition is that cross winds have to be less than 20kt and tail winds less than 5kt.
The problem came to light when several pilots contacted the senator with concerns about the increase in the risk of a mid-air collision if the planes using the crossed runways both had to abort their landings.
Xenophon was quoted by ABC News as saying: "It's not just one pilot, it's quite a few pilots who are particularly concerned. They were really worried about it. They thought the risk of something going wrong in a go-around in those cross winds could have led to a mid-air collision."
AA executive general manager for air traffic control Greg Hood said that AA was conducting a review into how the rules had been changed without any risk assessment or safety analysis being done. He also said that he has taken immediate action to ensure that the procedure has been amended.