The third launch of Cygnus using an Atlas V-401 booster commenced successfully on Tuesday April 18th from Cape Canaveral Air Force Station in Florida and berthed nominally to the ISS almost four days later.
OA-7 launching from SLC-41 at Cape Canaveral Air Force Station in Florida. Source: ULA
OA-7 sees the return of refrigeration/freezing (i.e. Polar) stowage, an asset missing since Orb-3, which helps offset the increased late load for those science experiments that can be frozen. Because of the fairing surrounding Cygnus, it has a 10+ day late load capability and hasn’t been used much for perishable science that requires a short duration between handover and berthing/de-stow.
For reference, late load science for this mission was handed over and stowed on Cygnus during the first week of March (when the launch date was March 24th). Late load for biologicals on Dragon can be as late as 28 hours before launch.
Inside the Cygnus OA-7 pressurized cargo section. Note the four Polar freezers in the forefront. Picture: NASA.
Cargo By the Numbers
The science cargo mass (table below) is a little higher than previous missions, likely due to the refrigeration support hardware and the Saffire-III experiment, both which are large ...