Singapore Technologies Aerospace (ST Aerospace) has reported a 57 per cent decline in net profit to S$27.4 million (US$18.5 million) for the first quarter 2009 compared with the year-ago period. On a quarter-on-quarter basis, profit was down 30 per cent from the fourth quarter of 2008. Turnover was down marginally by 2 per cent for the first quarter, year-on-year, to S$459 million.