Henderson-based shipbuilder Austal has taken a step towards a long mooted defence contract after the US Navy exercised an option to fund the purchase of long lead time equipment for two additional vessels, valued collectively at $450 million.

Henderson-based shipbuilder Austal has taken a step towards a long mooted defence contract after the US Navy exercised an option to fund the purchase of long lead time equipment for two additional vessels, valued collectively at $450 million.