BAE Systems is to upgrade four legacy Watchman Air Traffic Control Radars used at Ministry of Defense airfields in Britain and abroad.

The contract, worth about $10.8 million, comes under the Marshall program led by Aquila, a joint venture between Thales UK and NATS to provide air traffic management services.

NATS Holdings, formerly known as National Air Traffic Services, is the main air navigation service provider in Great Britain.

Under the award, BAE Systems will perform the technology upgrade to extend the operational life of the Watchman systems -- designed in the 1980s -- by using the latest technology found on its Sampson, Artisan and Commander radars.

"This is an important contract because it demonstrates the benefit of taking a through-life service view," said BAE Systems Maritime Services' Product and Training Services Director Les Gregory. "Using technology from our newest radars, we will extend the life and improve the performance of an essential asset for the Ministry of Defense for at least a further 20 years."

BAE Systems said that upgrading The Watchman systems with new transmitters and new signal processing technology, operators will benefit from increased Watchman performance and easier maintenance.