
Each Dream Chaser is designed for at least 15 missions, though engineers are optimistic the vehicle could be certified for more. Tenacity completed static and pressure testing last March and is pictured being moved onto the structural evaluation stand earlier last year.

The skeletal composite airframe of the second Dream Chaser, “Tail 2” or DC-102, stands inside Sierra Space’s Louisville, Colorado, final assembly facility as completion work on sister ship DC-101 Tenacity proceeds in the background.

An aft view of DC-101 shows the airlock where it will be mated to the cargo module. The main body assembly, which includes the pressured cabin, is constructed from high-temperature-resistant carbon-fiber/bismaleimide (BMI) composite skins cobonded with composite bulkheads and ring frames. The large fin-like wings are similarly made from BMI skins cobonded to composite ribs and spars.

Sierra Space designed and built the first Dream Chaser cargo module—dubbed Shooting Star—in-house, but will produce future vehicles with Spirit AeroSystems under a strategic partnership announced last May. The module is designed to carry around 4,500 kg (9,900 lb.) of pressurized and unpressurized cargo and is configured with both solar panels and thrusters. Although the Dream Chaser is reusable, the cargo module is jettisoned before reentry and burns up in the atmosphere. Expanded roles for future cargo module derivatives are under study by Sierra Space.

Sierra expects to decide later this year or in early 2024 whether it will need to add a third DC-100-series Dream Chaser or instead transition directly to production of the larger DC-200 optionally crewed follow-on version. Tenacity, along with the cargo module, will shortly be shipped to NASA’s Neil Armstrong Test Facility (formerly Plum Brook Station) in Ohio for thermal testing.

The Dream Chaser’s BMI composite structure can handle high temperatures, but not the 2,500F-plus that the vehicle sees on reentry, so the exterior needs to be shielded by a thermal protection system (TPS). The bulk of this is made up of more than 2,200 individually attached ceramic tiles, while Nomex-type TPS blankets protect the remaining structure around the aft deck and rudder elevons. More reflective white tiles provide protection for on-orbit operations while the black tiles are for reentry.

The initial seven Dream Chaser DC-100-series NASA resupply missions to the ISS will be launched by United Launch Alliance’s (ULA) new Vulcan Centaur launch vehicle—the first flight of which is scheduled early this year to loft Astrobotic’s Peregrine lunar lander toward the Moon for NASA’s Commercial Lunar Payload Services program. For these flights the Dream Chaser’s deployable wings will be folded for encapsulation within the vehicle’s 17.7-ft.-dia. payload fairing. The combined Dream Chaser and Cargo Module stack is 55 ft. tall.

Built to normally accommodate 13 positions during operations, including a NASA liaison officer, plus additional support staff, Sierra Space’s Dream Chaser Mission Control Center in Louisville will eventually be used by a team of up to 80 staff working on four shifts to support 24/7 operations. Currently contracted by NASA for seven ISS resupply missions, Sierra expects the tempo of operations to increase significantly with the introduction of the second Dream Chaser and the start of flights to new orbital habitats later this decade.

Differentiated from the DC-100 series by a 40% increase in size, upper-body windows and fixed wings, the redesigned DC-200 is expected to be flight-tested without a crew in late 2025—and with astronauts onboard in 2026. Although design details are yet to be finalized, the DC-200 is likely to be configured with lower body-mounted wings and twin canted tails, similar to the Boeing X-37, and will feature a simpler outer mold line without the pronounced upper-body hump of the baseline version.

Sierra Space’s plans do not stop at the Dream Chaser. The company is also developing its LIFE (Large Integrated Flexible Environment) inflatable platform technology under NASA’s NextStep project for space habitation systems, as well as working with Blue Origin and other partners under the Orbital Reef project. Full-scale burst tests of the woven material used for the inflatable structure are set for 2023 following two successful subscale ultimate burst pressure (UBP) tests in 2022 at Redstone Arsenal in Huntsville, Alabama.
Video of the UBP test can be seen here.
Sierra Space has set its sights on development of a space ecosystem in low Earth orbit, the first element of which is the Dream Chaser spaceplane. Due to make its debut spaceflight to the International Space Station in late 2023, the Dream Chaser and follow-on derivatives are also designed to service a new set of orbital business parks and platforms, the technology for which is also under test and development by Sierra Space in association with NASA and other partners, including Blue Origin.
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