The Dream Chaser spacecraft, developed by Sierra Space, is a reusable lifting-body spaceplane that represents a significant step forward in the commercialization of space travel. Designed to transport cargo to and from low-Earth orbit (LEO) destinations, such as the International Space Station (ISS), the Dream Chaser combines the flexibility of an aircraft with the capabilities of a spacecraft. With its unique design and advanced features, the Dream Chaser is poised to revolutionize space transportation and open up new possibilities for scientific research, technological advancements, and economic opportunities in space.

Design and Capabilities

The Dream Chaser’s lifting-body design allows it to generate a significant amount of lift during re-entry into the Earth’s atmosphere, providing a gentler descent and landing experience compared to traditional capsule-based spacecraft. This low-G re-entry, typically around 1.5G, is particularly beneficial for sensitive scientific experiments and potentially for future crewed missions.

One of the most notable features of the Dream Chaser is its foldable wings, which enable it to fit within the payload fairings of various launch vehicles, such as the United Launch Alliance’s Vulcan Centaur rocket. This compatibility with multiple launch systems offers flexibility in mission planning and execution.

The Dream Chaser is designed for high reusability, with each spacecraft capable of performing a minimum of 15 missions. After landing on conventional runways, the spaceplane can be quickly refurbished and prepared for its next launch, significantly reducing the cost and turnaround time between missions.

Technical Specifications

The Dream Chaser measures approximately 30 feet (9 meters) in length and has a wingspan of 22 feet (6.7 meters) when its wings are extended. It can carry around 5,500 kilograms (12,125 pounds) of pressurized and unpressurized cargo to the ISS, and for return missions, it can bring back up to 1,850 kilograms (4,078 pounds) of cargo to Earth.

The spacecraft features an autonomous flight system, though it can also be operated manually by astronauts if necessary. Its thermal protection system (TPS) consists of silica-based tiles for most of the belly and upper portion of the heat shield, and a new composite material called Toughened Unipiece Fibrous Reusable Oxidation Resistant Ceramic (TUFROC) to cover the Shooting Star cargo module.

Cargo System

The Dream Chaser Cargo System (DCCS) consists of the spaceplane itself and an expendable cargo module called “Shooting Star.” The cargo module attaches to the back of the spacecraft, expanding its cargo capacity to approximately 5,000 kg of pressurized cargo and 500 kg of unpressurized cargo. On return missions, the Dream Chaser can bring back up to 1,750 kg of cargo to Earth, making it an essential tool for transporting experiments and materials from the ISS for further analysis.

The Shooting Star module not only carries supplies to the ISS but also serves as a disposal mechanism for waste generated on the station. Upon re-entry, the module burns up in the atmosphere, safely disposing of the waste while the Dream Chaser lands safely on a runway. The module’s name, “Shooting Star,” is a nod to what it will look like as it burns up during re-entry.

In addition to its cargo carrying capabilities, the Shooting Star module includes solar panels that can supply up to 6 kW of electrical power. It also provides active and passive thermal management, supports Dream Chaser’s translation and rotation capability via six mounted thrusters, and enables berthing or docking to the ISS in different configurations.

Development and Testing

Sierra Space has been rigorously testing and refining the Dream Chaser spacecraft to ensure its reliability and performance. The development process has included a series of captive carry tests, free-flight tests, and now, a final testing campaign at NASA’s Neil Armstrong Test Facility in Ohio.

In May 2023, Sierra Space achieved a major milestone by successfully powering up the Dream Chaser spaceplane for the first time. This power-up signified the activation of the spacecraft’s integrated systems, showcasing the culmination of years of rigorous engineering, design, and testing. Test engineers simulated the power that will be generated from Dream Chaser’s solar arrays once in orbit, plugged that power into the spacecraft, and began turning on systems, including flight computers, base processors, and low-voltage distribution units.

Future Missions and Applications

Under NASA’s Commercial Resupply Services 2 (CRS-2) contract, the Dream Chaser is set to perform at least six cargo resupply missions to the ISS. These missions will play a crucial role in maintaining the station’s operations, delivering vital supplies, and returning scientific experiments to Earth.

Looking beyond its cargo missions, the Dream Chaser’s unique capabilities make it suitable for a wide range of applications. Its low-G re-entry and runway landing capabilities are particularly attractive for sensitive scientific payloads and the potential future transport of astronauts. Sierra Space has expressed interest in developing a crewed version of the Dream Chaser, which could carry up to seven astronauts to LEO destinations.

Moreover, the Dream Chaser’s versatility could extend to missions beyond the ISS, such as servicing a planned lunar gateway or supporting other cislunar activities. The spacecraft can dock or berth with other space stations, and with the addition of robotic arms, it has the potential to boost satellites to higher orbits, pull them out of orbit, and possibly make repairs.

Conclusion

The Sierra Space Dream Chaser spacecraft represents a new era in commercial spaceflight, offering a reusable, flexible, and cost-effective solution for cargo and potentially crew transportation to LEO. With its advanced design, gentle re-entry capabilities, and compatibility with multiple launch vehicles, the Dream Chaser is well-positioned to support the growing demands of the space industry.

As the Dream Chaser progresses through its final testing phase and prepares for its first mission in 2024, it is clear that this innovative spaceplane will be a significant player in the future of space exploration and commercialization. By providing reliable access to space and supporting cutting-edge research and technological advancements, the Dream Chaser is helping to pave the way for a thriving space economy in the years to come.