The Sierra Dream Chaser is a highly innovative spacecraft designed and built by Sierra Nevada Corporation (SNC). It is part of NASA’s Commercial Resupply Services 2 (CRS-2) program and represents a significant step forward in reusable spacecraft technology. Its primary function is to carry cargo to and from the International Space Station (ISS), though its design also allows for potential human spaceflight missions in the future.
Design and Capabilities of the Dream Chaser
The Dream Chaser spacecraft is a lifting-body vehicle, which means that its body generates a significant amount of lift as opposed to relying solely on wings. This design is advantageous for re-entry into the Earth’s atmosphere because it provides a gentler descent and landing experience compared to capsule-type spacecraft. The Dream Chaser has foldable wings, which allows it to fit within the payload fairings of various launch vehicles.
One of the most important features of the Dream Chaser is its reusability. The spacecraft is designed to be used for a minimum of 15 missions. After landing, it can be refurbished and launched again, significantly reducing the cost and time between missions. The Dream Chaser lands on conventional runways, which means it can touch down at a wide range of locations, providing flexibility for mission planning and cargo retrieval.
The cargo module of the Dream Chaser, known as the Shooting Star, is an attachment that increases the vehicle’s cargo capacity. It not only carries supplies to the ISS but also serves as a disposal mechanism for waste. The Shooting Star burns up on re-entry, safely disposing of the station’s waste.
Technical Specifications
The Dream Chaser is approximately 30 feet long, with a wingspan of 22 feet when the wings are extended. It is capable of carrying around 5,500 kilograms of pressurized and unpressurized cargo to the ISS. For return missions, it can carry up to 1,850 kilograms back to Earth. This capability is significant for transporting experiments from the ISS that require analysis on Earth.
The Dream Chaser is designed to be compatible with a variety of launch vehicles, providing flexibility in terms of launch options. It has an autonomous flight system, though it can also be operated manually by astronauts if necessary.
Development and Missions
The Dream Chaser’s development has been marked by a series of tests, including captive carry and free-flight tests, to validate its design and flight capabilities. The development process has demonstrated the spacecraft’s ability to glide and land autonomously, which is a testament to its advanced avionics and flight software.
Under the CRS-2 program, the Dream Chaser is contracted for at least six cargo resupply missions to the ISS through 2024. These missions will be important to maintaining the ISS’s operations, delivering vital supplies, and returning scientific experiments to Earth.
The Future of Dream Chaser
Looking beyond its initial cargo missions, the Dream Chaser’s design is also being considered for other potential applications. Its ability to provide a low-g-force re-entry could be particularly beneficial for sensitive scientific experiments and the transport of astronauts. SNC has expressed interest in developing a crewed version of the Dream Chaser, which could transport up to seven astronauts to low-Earth orbit destinations.
Moreover, the Dream Chaser might play a role in future space endeavors beyond the ISS. Its design makes it suitable for potential use in missions to a planned lunar gateway or for other cislunar activities as part of a broader space exploration strategy.
Summary
The Sierra Dream Chaser is a cornerstone in the current era of commercial spaceflight. Its reusable design, flexible launch compatibility, and gentle landing capabilities position it as a unique solution for cargo and potentially crew transport to the ISS and beyond. As the space industry continues to evolve with a focus on sustainability, cost-efficiency, and versatility, the Dream Chaser is poised to be a significant player in the global space community’s efforts to maintain a robust presence in low-Earth orbit and to lay the groundwork for future exploration endeavors.
