THE Irish Aviation Authority made a pre-tax profit of £4.6 million last year, a 13 per cent increase on the previous 12 months.

Turnover at the fledgling semi-state body, which manages 100,000 sq. miles of Irish air space and regulates the safety standards of Irish based aviation companies, increased by 5 per cent from £46.6 million to £48.9 million.

More than half of the authority's income is derived from aircraft which fly over Ireland between Europe and North America, as more than 60 per cent of such traffic passes through Irish airspace. The chief executive of the Irish Aviation Authority, Mr Brian McDonnell describes Ireland as. "The marshalling yard between Europe and America".

Fees from air traffic control account for about 82 per cent of the agency's turnover, and this income will increase over the next five years when civil aircraft traffic is expected to grow by about 5 per cent per annum. En route traffic increased by over 8 per cent last year to 174,000 movements, and grew by another 8 per cent in the first six months of this year.

However, the Aviation Authority's income will not necessarily rise in line with the expansion in air traffic as its charging structure is based on recovering costs and making some profit for re-investment. The largest future investment is in a new air traffic control centre at Shannon, which is expected to cost £25-£30 million to complete.

Operating costs as a percentage of turnover fell from 92.4 per cent to 90.9 per cent, while staff costs as a percentage of total costs increased from 48.2 per cent to 49.9 per cent. During the year a lightning strike on the authority's radar system at Dublin airport caused £1.5 million in damage.