The Atlas 5 booster's liquid oxygen vent valve issue caused a second scrub of the ViaSat-3 F2 launch, halting the countdown for the second night in a row. The launch, scheduled for 10:16 p.m. EST on Thursday, was postponed due to a recurring problem with the vent valve on the first stage liquid oxygen tank during final pre-launch checks. This valve issue, which prevented a launch on Wednesday night, persisted on Thursday, leading to the scrub. Launch Director James Whelan made the decision to cancel the attempt, and ULA announced the launch was scrubbed for the night. The team will evaluate the hardware, and a new launch date will be announced when available.
The weather also played a role in the scrub. Skies at Cape Canaveral were overcast with thick clouds and rain showers, and the Launch Weather Officer downgraded the outlook, giving a 50-50 chance of meeting the launch weather rules. The primary concerns were thick-layered clouds and rain.
The ViaSat-3 F2 satellite, manufactured by Boeing and weighing 6 metric tons, is designed to provide Ka-band network capabilities, adding over 1 terabit per second (Tbps) of capacity to Viasat's network over the Americas. It is the second satellite in the ViaSat-3 series, following the launch of ViaSat-3 F1 by SpaceX Falcon Heavy in 2023, which suffered an antenna issue, delaying service and reducing capacity.
The ViaSat-3 F2 is expected to enter service in early 2026 after months of on-orbit testing at its operating location of 79 degrees West longitude. This mission will use the Atlas 5's hydrogen-fueled Centaur upper stage, which will fire three times and use the majority of its propellant to send the satellite into a geostationary transfer orbit, potentially extending its lifetime.
