Sierra Space’s Dream Chaser spacecraft is now being prepared for its first space mission

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NASA and Sierra Space are making progress ahead of the maiden flight of the US space company’s Dream Chaser spacecraft to the International Space Station. The uncrewed cargo plane is scheduled to launch its test mission to the space station in 2024 as part of NASA’s commercial resupply services. Sierra Space, formerly Sierra Nevada Corporation, was selected in 2016 to be NASA’s third commercial cargo spacecraft under the Commercial Resupply Services program that selects private space companies to resupply the International Space Station.

Dream chaser and shooting star

The Dream Chaser cargo system, produced by Sierra Space in Louisville, Colorado, consists of two main components: the Dream Chaser spacecraft and the Shooting Star cargo module. Dream Chaser is a lifting body spacecraft designed to be reused up to 15 times and adapted from the HL-20 spacecraft developed at NASA’s Langley Research Center in Hampton, Virginia. The cargo module accompanying the spaceplane, Shooting Star, is designed to support the delivery and removal of pressurized and non-pressurized cargo to and from the space station. The charging unit can only be used once and will be discarded before the Dream Chaser returns to Earth.

The Dream Chaser system will be launched with its wings folded into a five-meter width aboard a ULA (United Launch Alliance) Vulcan Centaur rocket from Space Launch Complex 41 at Cape Canaveral Space Force Station in Florida. Fairing panels protect the spacecraft during launch, but are discarded in orbit. Solar panels on the Dream Chaser’s cargo module and wings are deployed during an autonomous rendezvous with the International Space Station. In the case of the Scrub, the Dream Chaser is designed to be ready to launch within 24 hours.

The Dream Chaser spacecraft is 9 meters long and is designed to transport cargo and people into space. Sierra Space also wants to eventually use the Dream Chaser to transport people to a commercial space station. The Dream Chaser’s design is based on that of NASA’s HL-20 spacecraft from the 1980s.

The Dream Chaser spacecraft undergoes final testing – Image: NASA/Sierra Space

Task overview

During the maiden flight, Sierra Space will conduct in-orbit demonstrations to certify the Dream Chaser for future missions. Teams at NASA’s Kennedy Space Center in Florida, NASA’s Johnson Space Center in Houston, and the Dream Chaser Mission Control Center in Louisville, Colorado, will closely monitor the flight. Sierra Space flight controllers will operate the Dream Chaser spacecraft on the launch pad until the spacecraft is delivered to Sierra Space’s ground operations team at NASA Kennedy after landing.

In-orbit demonstrations will be performed outside the space station’s vicinity before the spacecraft enters the approach zone, an invisible 4-by-2-by-2-kilometre boundary around the space station in low Earth orbit. These demonstrations are necessary before Dream Chaser can begin joint operations with the NASA team at Mission Control in Houston. This includes showing control of the situation, maneuvers, and aborting.

The demonstrations to be performed near the space station include activating and using light and remote control (LIDAR) sensors, responding to space station commands, withdrawing from the station when requested and maintaining its approach, first at an altitude of 330 metres, then 250 metres. Finally 30 meters from the station. After the successful completion of the demonstrations, the Dream Chaser will move toward the space station. As the Dream Chaser approaches the space lab, it will remain about 37 feet (11.5 meters) from the space station for the final time, when a station crew member uses the Canadarm2 robotic arm to grab the arm of the spaceship’s cargo module ahead of the teams on deck. Install the grounded charging unit into a floor-facing outlet on your Unity or Harmony unit.

On its maiden voyage to the International Space Station, Dream Chaser will deliver more than 3.5 tons of cargo. For future missions, the Dream Chaser is designed to remain attached to the station for up to 75 days and deliver up to 5.2 tons of cargo. Cargo can only be loaded onto the spacecraft 24 hours before launch. The Dream Chaser can return more than 1.5 tons of cargo and experimental samples to Earth, while more than 3.9 tons of waste can be removed during reentry using the cargo module.

Back to earth

Dream Chaser will remain on the space station for approximately 45 days before being removed using Canadarm2. The spaceship can land as early as 11 to 15 hours after departure, with daily options available if weather criteria are met. Weather criteria for a Dream Chaser landing generally require crosswinds of less than 15 knots, headwinds of less than 20 knots, and tailwinds of less than 10 knots. Thunderstorms, lightning, and rain within 20 miles of the runway or 10 miles along the flight path are not acceptable conditions for landing. Detailed flight rules will guide controllers in determining whether landing options are favourable.

A set of 26 reaction control propulsion systems will be fired from the Dream Chaser to launch the spacecraft into orbit. The Dream Chaser will reenter Earth’s atmosphere and glide onto the runway at NASA’s Kennedy Space Shuttle Launch and Landing Facility, the first spacecraft to land at the facility since the last Space Shuttle flight in 2011. Once the Dream Chaser is deactivated after landing, the operations team will The ground at Sierra Space will be transported to the Space System Processing Facility to conduct the necessary inspections, unload the remaining NASA payload, and begin the process of preparing it for the next mission.

source: NASA