United Launch Alliance called off the planned launch of an Atlas 5 rocket Wednesday at Cape Canaveral to resolve a problem with valves at the launch pad, while a SpaceX team a mile-and-a-half to the south readied a Falcon 9 rocket for liftoff Thursday evening with a GPS navigation satellite for the U.S. military.
ULA’s launch team scrubbed the Atlas 5 launch attempt Wednesday shortly before 6 p.m. EST (2300 GMT) after unsuccessful attempts to fix the valve issue, first remotely and then with a team of technicians dispatched to the Atlas 5’s seaside launch pad.
The Atlas 5 rocket will carry a classified payload into orbit for the National Reconnaissance Office, the U.S. government’s spy satellite agency. The launch is designated NROL-101, and the NRO has not disclosed any specifics about the payload’s mission, other than it will help the agency in its mission to collect and disseminate information for the government’s intelligence agencies.
ULA started the Atlas 5’s countdown late Wednesday morning, powered up the rocket, and proceeded with guidance system testing and other checkouts before loading cryogenic propellants into the launcher ahead of a planned liftoff at 5:54 p.m. EST (2254 GMT).
But the launch team stopped the countdown clock after an “unexpected system response from remotely commanded ground system liquid oxygen valves,” ULA said in a statement.
“The team continues to analyze the system and will protect for our next launch attempt no earlier than Nov. 6,” ULA said.
The next opportunity to launch the Atlas 5 rocket will be Friday, ULA said. An exact time for Friday’s launch attempt was not immediately announced, but the mission’s launch time has moved about four minutes earlier per day. That would put Friday’s launch time at around 5:46 p.m. EST (2246 GMT).
The Atlas 5’s launch was previously scheduled for Tuesday, but ULA returned the rocket to its vertical hangar near the launch pad to replace an environmental control system duct feeding conditioned air to the top secret NRO payload on top of the 206-foot-tall (63-meter) vehicle.
Ground crews returned the Atlas 5 to its launch pad late Tuesday in preparation for the launch attempt Wednesday.
Before the next Atlas 5 launch opportunity, SpaceX plans to launch a Falcon 9 rocket from nearby pad 40 during a 15-minute window opening at 6:24 p.m. EST (2324 GMT) Thursday.
The 229-foot-tall (70-meter) Falcon 9 rocket was standing on pad 40 Wednesday in preparation for launch Thursday evening. Pad 40 is located about a mile-and-a-half (2.5 kilometers) south of the Atlas 5 launch pad at Cape Canaveral.
