NASA Dumps Dream Chaser

Is this the end of the line for Sierra Space's Dream Chaser? 

Word broke on Thursday that NASA modified its contract with Sierra Space for cargo missions to the ISS cancelling guaranteed cargo flights and replacing them with essentially a single test flight that won't dock with the ISS.  

What began as a hopeful contender in NASA’s Commercial Crew Program has now been relegated to a free-flying test mission targeted for no earlier than late 2026—likely slipping into 2027—leaving its role in space station operations uncertain.

Short (4:22) video from NASASpaceflight.com.

The history of the Dream Chaser goes back to the last years of the Space Shuttle era, and a space plane called the HL-20 lifting body developed in the 1990s.  

Image of the HL-20. Credit: NASA 

In 2008, Sierra Nevada Corporation (now Sierra Space) acquired the design and pitched it for NASA’s Commercial Crew Development (CCDev) program, securing funding through phases 1 and 2, as well as the Commercial Crew integrated Capability (CCiCap) stage.

Despite these early investments, Dream Chaser was ultimately passed over in 2014 when NASA selected SpaceX’s Crew Dragon and Boeing’s Starliner for crewed missions to the ISS. Sierra Nevada protested the decision with the U.S. Government Accountability Office but lost the appeal.

This led to a change of emphasis for Sierra Space, shifting directions when the Commercial Resupply Services-2 (CRS-2) contract to carry cargo to the ISS was opened. This is the program both SpaceX’s Cargo Dragon and Northrop Grumman’s Cygnus spacecraft are operating  under. Sierra Space was awarded a contract under CRS-2 for a minimum of seven ISS resupply flights with Dream Chaser and its companion cargo module, called Shooting Star. Nine years later, however, Dream Chaser has still not reached space and its cargo deal has just been changed.

"After a thorough evaluation, NASA and Sierra Space have mutually agreed to modify the contract, as the company determined Dream Chaser development is best served by a free flight demonstration, targeted in late 2026," agency officials said in an emailed statement on Thursday (Sept. 25).

"Sierra Space will continue providing insight to NASA into the development of Dream Chaser, including through the flight demonstration," they added. "NASA will provide minimal support through the remainder of the development and the flight demonstration. As part of the modification, NASA is no longer obligated for a specific number of resupply missions; however, the agency may order Dream Chaser resupply flights to the space station from Sierra Space following a successful free flight as part of its current contract."

The unavoidable consequence of being late is that the station itself is on its last legs, and while there is no firm, fixed date for taking it out of orbit, it looks to easily be NET (No Earlier Than) 2030, and the latest date I've seen is in 2031.  If the earliest possible launch of a test flight for Dream Chaser is 2026, with 2027 certainly looking possible, coordinating a test flight with the real cargo to be delivered to the ISS could be an issue.

On October 24, 2023, Sierra Space moved the Shooting Star cargo module into position behind the Dream Chaser spaceplane for checkouts before shipment to Ohio for environmental testing. Image credit: Shay Saldana/Sierra Space.  More details here. 

Sierra Space isn't saying they're giving up, but they're absolutely between the proverbial rock and a hard place.  

NASA’s statement emphasized that the shift prioritizes Sierra Space’s development needs, enabling data collection in a lower-risk environment. Potential underlying reasons for the modification, based on industry insights, include:

Ongoing development challenges at Sierra Space are hindering readiness for flight. Concerns over the timely certification processes required for ISS operations. NASA’s reluctance to allow an unproven vehicle near the station, especially given the need for rigorous safety standards in proximity to crewed habitats.

While Sierra Space has not publicly detailed the issues, the company’s determination to fly Dream Chaser for learning purposes may have clashed with NASA’s risk-averse approach to ISS missions.

NASA has been noncommittal about Dream Chaser, saying, ”we might potentially order resupply missions if needed” which doesn't offer much encouragement.  In fairness, it could be that SpaceX and Northrop Grumman have done such a good job getting cargo to the ISS they're not really concerned about Dream Chaser as a last option.  They've been doing it flawlessly since the shuttle fleet was grounded in 2011, (with some contribution from the Russians until the last few years).  Perhaps Sierra is just so late they don't matter any more.