Sierra Space’s Dream Chaser spaceplane has been removed from the manifest for United Launch Alliance’s (ULA) second Vulcan Centaur flight due to scheduling delays. Instead, an “inert payload” will take its place. This decision was made after Sierra informed ULA of the significant risk of not meeting the September launch date. ULA CEO Tory Bruno mentioned during a press conference that Sierra chose to step aside so that ULA could continue with its certification process with the Department of Defense (DOD). The certification is crucial as it will allow the new rocket to carry out national security missions for the DOD. ULA successfully launched the first Vulcan mission earlier this year.
Alongside the inert payload, ULA plans to launch technology “experiments and demonstrations,” although Bruno did not provide further details during the press conference. Additionally, ULA has scheduled at least two more Vulcan missions before the end of the year. These missions, known as USSF-106 and USSF-87, are part of a series of backlogged launches contracted with the DOD.
Despite the slip in the launch schedule, Sierra Space confirmed in a separate statement that its first Dream Chaser spaceplane, named Tenacity, remains on track for its maiden mission before the end of the year. Tenacity, equipped with its expendable Shooting Star cargo module, recently completed environmental testing to ensure its resilience during launch and orbit. After being delivered to NASA’s Kennedy Space Center in Florida, final testing is currently underway before its launch.
Unlike SpaceX’s Dragon or Boeing’s Starliner, Sierra Space’s Dream Chaser spaceplane is designed to land horizontally on a runway, similar to NASA’s retired space shuttle. Its primary purpose is to deliver cargo resupply missions to the International Space Station (ISS) for NASA, but its development has faced significant delays. Sierra Space was awarded the Commercial Resupply Services 2 (CRS-2) contract in 2016, with the expectation of starting mission fulfillments in late 2019.
For its first mission under the CRS-2 contract, Dream Chaser will carry 7,800 pounds of cargo to the ISS. It will spend 45 days attached to the station before returning to Florida for inspection, refurbishment, and reuse.
In addition to the cargo version, Sierra Space is also planning a crewed version of the Dream Chaser spaceplane and an inflatable habitat module that could function as a private space station in low Earth orbit. The company has raised $1.7 billion to date to support its various space projects.