Shareholders in Qinetiq, the defence research group with a major facility at Malvern, could tomorrow trigger the firm's £1 billion float on the stock market.

Sources close to the negotiations yesterday said that shareholders could give the go-ahead for Qinetiq's long awaited IPO (initial public offering) sometime around mid-February.

"It is ready to go now - and an IPO is imminent - but it is all subject to a final decision," a sector watcher said.

"There is a meeting on Wednesday and it may be the meeting where the go-ahead is given. But it could also be the meeting after that, or the one after that."

However, other sources said the Qinetiq board and its two shareholders - US private equity firm Carlyle Group and the Ministry of Defence - would each have to approve any decision.

They will review plans for the IPO by bookbuilders Credit Suisse First Boston, JP Morgan and Merrill Lynch. ABN AMRO Rothschild is acting as an independent adviser.

Carlyle took its 31 per cent stake in 2003, pledging an IPO within five years.

Formerly the technology development arm of the MoD, Qinetiq technology includes scanners which can spot concealed weapons, stowaways on trucks and debris on runways.

In its last full-year results, Qinetiq posted an operating profit of £69.6 million on turnover of £872.4 million.

Meanwhile, Qinetiq's Air Traffic Management team, in collaboration with Boeing Research and Technology Europe (BR&TE), has won a significant study contract worth 170,000 euros (£115,000) from the Eurocontrol Agency in Brussels.

Qinetiq and BR&TE will review existing and planned aircraft arrival management tools for air traffic controllers in order to develop new concepts for increasing capacity at European airports.

Qinetiq will lead a team of experts which will provide advice on aircraft performance and flight management systems.

The study forms a key step in a Eurocontrol initiative which aims to ensure increased capacity at airports to meet the predicted doubling of traffic demand over the next decade.

Qinetiq bid and project manager Andy Taylor, a senior operational consultant in the ATM Group, said: "Winning this important study shows that Qinetiq and BR&TE are at the heart of European ATM, and can provide solutions to ATM challenges by combining their complementary skills."

Qinetiq said the Eurocontrol contract was timely because the firm has only recently been accepted onto the US Next Generation Air Transportation System (NGATS) Programme, which will look at the development of the US air transport system over the coming years and which aims to triple air transport capacity by 2020.

Qinetiq is the only non-US organisation to be represented.