The US Air Force has received the final first stage motor for the Minuteman Intercontinental Ballistic Missile (ICBM) under its ten-year propulsion replacement programme.

The replacement is one of the several large Minuteman ICBM force modernisation programmes managed by Northrop Grumman.

Re-manufacturing of the ICBM motors includes replacing ageing propellant and obsolete or environmentally unsafe materials and components.

The second and third stage motors are being built by ATK and are expected to be delivered later in August 2009.