Qinetiq, the defence firm floated by the UK government, has reported pre-tax profits up 37.6% to £80.1m ($149m) in its first results since the listing.
Qinetiq now must compete for government contracts
Turnover at the company increased by 23% to £1.05bn.
Sales have soared in North America with heightened security raising demand for products such as airport scanning and border control devices
Other products include military sensors and software, banking security systems and desert kits for helicopters.
Qinetiq said that tight budgets on both sides of the Atlantic meant it would have to invest in technology and rationalise to fulfil its potential.
The firm was previously guaranteed government work, but now must compete against rivals for lucrative UK contracts.
The company - which employs more than 11,400 people - has clients ranging from the Pentagon to jet engine firm Rolls-Royce and credit card company Barclaycard.
Qinetiq's flotation in February this year, the first by this Labour government, attracted criticism because of the amount of money that US investor Carlyle Group made from the privatisation.
But ministers defended the listing, saying taxpayers were getting value for money.
The company's shares were launched at 200 pence each, but have recently been trading at about the 175p mark.
They have been underperforming the UK aerospace and defence sector by around 11 percent.