EDWARDS AIR FORCE BASE, Calif. — Sierra Nevada Corporation (SNC) carried out a successful captive carry test Aug. 30 of its Dream Chaser vehicle, a key step towards a glide flight of the lifting body spacecraft later this year.
The Dream Chaser engineering test article, slung underneath a civilian variant of the Chinook helicopter, took off here at 10:21 a.m. Eastern. It landed at 12:02 p.m. Eastern, with the company declaring the flight a success.
During the test, SNC collected data on the vehicle’s performance in flight, including operation of radar altimeters, air data probes and other systems that cannot be fully tested on the ground. The captive carry test followed a series of tow tests here in recent months, where the vehicle was towed behind a truck down a runway at speeds of up to 100 kilometers per hour.
“It went as good as we could possibly expect,” said Steve Lindsey, vice president of space exploration systems for SNC, during a briefing here after the completion of the flight. “From what we saw in real time, everything was working exactly as expected.”
This captive carry flight is one of the final steps before a free flight, where Dream Chaser will be carried aloft by the helicopter and released to make a runway landing. That glide flight is the remaining funded milestone in the company’s Commercial Crew Integrated Capability (CCiCap) Space Act Agreement with NASA that the agency awarded in August 2012.
A second captive carry flight, expected to take place in about a month, will incorporate lessons learned from this flight, the company said. That will be followed by a free flight test before the end of the year.
Dream Chaser has performed one glide flight previously, in October 2013, as part of an earlier Commercial Crew Development award. The vehicle landed on the runway here but skidded off when part of its main landing gear collapsed. The vehicle did not suffer significant damage, and both the company and NASA considered the flight a success.
The vehicle that flew on its captive carry flight is the same as the one used for the 2013 tests, after repairs and upgrades. The vehicle now has the same avionics system that the company plans to use on its orbital vehicle, Lindsey said.
This flight also allowed the helicopter pilots to familiarize themselves with carrying the Dream Chaser. This flight used a different model of helicopter as the earlier series of flights. “For the helicopter pilots, it was a learning curve for them, learning how to get our vehicle into the drop box,” the airspace location where the vehicle would be released on a glide flight, he said. “They did a great job.”
SNC developed Dream Chaser to transport astronauts to and from the ISS. However, NASA instead selected proposals from Boeing and SpaceX in September 2014 for full-scale development of those vehicles. SNC filed a protest with the U.S. Government Accountability Office about that decision, but the GAO rejected the protest in January 2015.
The company has since been focused on development of a version of the vehicle to transport cargo. NASA awarded SNC a Commercial Resupply Services (CRS) 2 contract in January 2016, joining existing cargo providers Orbital ATK and SpaceX and guaranteeing the company at least six cargo missions between 2019 and 2024. The cargo version is similar to the crew version, but includes a separate module attached to the rear of the vehicle to carry additional cargo.
SNC announced July 19 it signed a contract with United Launch Alliance for the first two launches of Dream Chaser cargo spacecraft on Atlas 5 552 rockets. The first launch is scheduled for 2020 and the second in 2021, although Lindsey said that NASA has not formally ordered any Dream Chaser flights under its CRS-2 contract yet.
While SNC is focused for now on developing the cargo version of Dream Chaser, the company has not closed the door on developing a crew version. Lindsey said the company recently signed a five-year unfunded extension of its CCiCap agreement with NASA to support potential future development of a crewed vehicle.
“We have some unfunded milestones where NASA will come in and look at our requirements and how we’re developing our cargo vehicle, look at the path or trace to the crewed vehicle, and help us out,” he said of the extended agreement with NASA.
“We’re going to do cargo first, and do the best we can with cargo and prove out the vehicle,” he said, “but our intent some day is to go back to crew as well. How and when is TBD.”