Aviation support services company BBA Aviation said on Friday that it's trading in line with its expectations, with group revenue down 5% on the previous year as a result of falling fuel prices, but on an organic basis, revenue was up 3%.Revenue in the company's Flight Support division was up 3% on an organic basis, with a recovery in business and general aviation in the US, although European markets remained challenging.Revenue in the Aftermarket Services division grew 2% on an organic basis. Despite continued weak market conditions, Engine Repair & Overhaul's volumes picked up during the period, said BBA."The recovery in our major market continues and it is pleasing to see some recovery in repair and overhaul volumes, which we expect will begin to feed through to overall performance in the second half of the year," said group chief executive Simon Pryce."Our businesses are well positioned and we remain confident that 2015 will be another year of good growth for BBA Aviation," he added.