Vulcan rocket undergoes adjustments before test-firing.

United Launch Alliance's Vulcan rocket was rolled back to a hangar for adjustments before proceeding with an engine test-firing after a tanking test. The Vulcan rocket will replace ULA's Atlas and Delta rocket families and will fly in several configurations, with varying numbers of strap-on solid rocket boosters and different payload fairing sizes available on each flight, depending on mission requirements. The inaugural flight will be the first launch to use new methane-fueled BE-4 engines from Blue Origin.