Blue Origin said Sunday that it lost a set of powerpack hardware for its BE-4 engine during a ground test mishap, dealing at least a minor setback to the development of a powerful U.S.-made propulsion system that United Launch Alliance says is the leading candidate to power the first stage of its next-generation Vulcan rocket.

Get a preview of Thursday’s United Launch Alliance Delta 4-Heavy rocket flight in these video highlights packages from previous missions by the big booster for NASA and the National Reconnaissance Office from Cape Canaveral in Florida and Vandenberg Air Force Base in California.

Constructing the launch pad infrastructure for astronauts to board Boeing’s Starliner crew capsules atop United Launch Alliance Atlas 5 rockets, workers delivered the Crew Access Arm with its White Room to Cape Canaveral’s Complex 41 on Thursday, Aug. 11.