Airport service worse at largest airports Worst service: Sydney Airport. The competition watchdog has lambasted Australia's five largest airports for deteriorating service levels and named Sydney Airport as the worst offender. In its annual report on the state of the country's airports, the Australian Competition and Consumer Commission calls for increased investment to avoid excessive congestion in the future. ACCC chairman Rod Sims said the overall level of service at the five largest airports - including Sydney, Melbourne, Brisbane and Perth - was lower in the 2011-12 financial year compared with 2010-11. For the first time since 2007-08, the regulator said, none of the five airports achieved an overall rating of at least "good." "It is apparent that continued growth in passenger numbers at most airports is placing pressure on existing aeronautical infrastructure, contributing to lower service standards," Mr Sims said. More investment is required to avoid excessive congestion. Mr Sims said Sydney Airport was of greatest concern given the "pattern of price and earnings increases, lower service standards and low investment levels compared with other airports." Sydney Airport again had the highest car parking revenue per space and margin per space, and the lowest ranking for overall quality of service. It also had the highest aeronautical revenue per passenger. Melbourne Airport's average prices increased but margins fell in 2011-12. It had the highest level of car parking revenue overall and the highest proportion of total revenues from car parking activities. The airport had the third-highest rating for overall quality of service. Brisbane Airport again received the highest ranking for quality of service, followed by Adelaide Airport which recorded falls in passenger numbers, average revenues and margins in 2011-12. But Sydney Airport said passenger satisfaction had risen to its highest level in a decade due to ""greater value and choice across the airport and strong investment in improved facilities"." ""We're listening to our customers and taking their feedback on board,"" the airport's chief executive, Kerrie Mather, said in a statement. She pointed to the report finding that Sydney was the only airport to have increased its passenger rating.