Sierra Space's lifting body will be the fourth crewed system in US service.
If you want to visit the international space station, there are two ways to get there: Dragon spacecraft, or by the Russian Soyuz system. A third option, Boeing’s Starliner, has flown an unmanned test, as part of a NASA space station resupply contract. NASA itself has the Orion spacecraft, although this is primarily designed for lunar and deep space exploration. These systems are about to be joined by a fourth: Sierra Nevada Corporation’s Dream Chaser, now ready for delivery to the NASA Armstrong Research Centre for testing. Why a fourth crewed spacecraft for ISS transportation? It’s part of a long-range NASA goal to increase competition in the commercial space industry and to provide redundancy to ensure uninterrupted station operations.
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Episode Transcript:
If you want to visit the international space station, there are two ways to get there: by Dragon spacecraft, or by the Russian Soyuz system. A third option, Boeing’s Starliner, has flown an unmanned test, as part of a NASA space station resupply contract. NASA itself has the Orion spacecraft, although this is primarily designed for lunar and deep space exploration.
Dream Chaser has been in development for years, but compared to the traditionally shaped capsules of the other systems, Dream Chaser is much like a miniature space shuttle.
The spacecraft has successfully completed its Approach and Landing Test, demonstrating the spacecraft’s ability to glide back to Earth and land safely. The reusability factor is expected to drive down the cost of space missions and current plans call for at least a 15-mission life expectancy for each airframe.
Dream Chaser can carry up to five crew members or a combination of crew and cargo, but compared to capsule based systems like Dragon and Starliner, the lifting body shape of the spacecraft and its aircraft-like landing mode allows easy recycling of the vehicle post flight, and with a cross range capability of about a thousand miles, it will be relatively easy to divert Dream Chaser to alternate landing zones if necessary. Staying in orbit for an extra day to avoid weather they become a thing of the past.
Another, potentially important benefit is the low G loading generated by the Dream Chaser re-entry profile, as low as 1.5 G’s. This may be important for sensitive scientific experiments returning from the ISS, and as an obvious implication for space tourism. Lifting the spacecraft into orbit may be accomplished using several different launch vehicles, with initial launches atop Vulcan Centaur, with a version under development to integrate with Arianespace launchers.
Dream Chaser represents the fourth crewed spacecraft from the United States alone, in addition to Russian and Chinese capability. And India is expected to launch astronauts soon as well. What human travel to Earth orbit become commonplace? Not yet, but Sierra Nevada’s Dream Chaser is the vehicle that’s the closest yet to airliner-type operations.
