US defence giant Lockheed Martin has won a key contract to build an air and missile defence system capable of detecting and shooting down threats, securing one of Australia’s most significant but little-known military contracts.

The Albanese government will on Tuesday name Lockheed Martin as the strategic partner for the project known as AIR6500, the air force’s multibillion-dollar vision to build an integrated network connecting sensors, radars and weapons such as fighter jets and warships to protect against missile attack.