Aviation support group BBA Aviation is seeing signs of a pick-up in North American business air travel, but Europe is still weak.BBA, which provides engine maintenance, re-fuelling and airport flight support services, said signs of recovery in business and general aviation (B&GA) - which involves private and business jets - in North America continued with movements up 4% in the first quarter.Markets stayed tough elsewhere, with European B&GA movements flat and commercial movements - which includes airlines - down 2% in North America and Europe.Overall trading in the four months to April 30th met its expectations with group revenue 1% higher than a year ago and up 2% excluding the impact of exchange rates, fuel prices, acquisitions and disposals.Chief Executive Simon Pryce said: "We have made a good start to the year. The recovery in our major market continues and we are dealing effectively with weaker European and commercial markets, with the group performing to plan."Our businesses are well positioned and we are therefore confident 2014 will be another year of progress."Shares fell 1.7p or 0.5% to 310.5p at 09:44 in London.PW