Mobile satellite services operator Inmarsat and satellite builder Boeing Space and Intelligence Systems have completed the critical design review for its three all-Ka-band Global Xpress mobile broadband satellites, London-based Inmarsat announced Oct. 12.

The milestone “marks the transition of the project from a design and engineering phase to a manufacturing, integration and test phase,” Franco Carnevale, Inmarsat’s vice president for space segment, said in a statement. “The review was completed earlier than scheduled, and [concluded] that the design is mature and there are comfortable margins with all key performance parameters.”

Inmarsat said sufficient progress has been made on securing components, including Ka-band travelling wave tubes, to keep the project on track for a launch in 2013. El Segundo, Calif.-based Boeing is building three Global Xpress satellites, which will be spaced along the geostationary arc over the equator to provide global coverage for military and corporate customers, except for the polar regions.

Separately, satellite insurance broker Willis Group announced Oct. 12 that it had won a competition to act as Inmarsat’s broker for the $1.2 billion Global Xpress program and for Inmarsat’s Alphasat I-XL satellite, to be launched in 2013.

Alphasat uses a new satellite platform designed by European builders with financing from the French and European space agencies. Willis also will be negotiating insurance coverage for Inmarsat’s current fleet of satellites.