Sierra Nevada Corporation (SNC) is quietly, but steadily, moving forward swiftly with the development of their reusable Dream Chaser spacecraft, and today SNC announced the successful completion a “flight-profile data review” milestone for Dream Chaser (as is required under the company’s Commercial Crew Integrated Capability “CCiCap” agreement with NASA).
The review milestone, known as CCiCap Milestone 4a, gave SNC engineers the opportunity to review data from Dream Chaser’s first autonomous free-flight test, known as ALT-1, which was conducted at Edwards Air Force Base / NASA Dryden Flight Research Center in southern California on Oct. 26, 2013.
Dream Chaser’s autonomous ALT-1 flight itself went about as good as SNC could have hoped for, until it came time to land. When the command was given to deploy its landing gear, only two of its three gear deployed, causing the engineering test vehicle to skid off the runway and sustain minor structural damage after touchdown. The problem, although not officially identified publicly yet by SNC, is suspected to have been a mechanical issue with the specific landing gear in question, rather than something related to bad software (none of the primary systems that gave the commands that control the flight failed or had any problems).
“Milestone 4a proved the Dream Chaser flies well and that the path the Dream Chaser will take throughout its expected flight profile can be reliably predicted,” said Mark Sirangelo, corporate vice president and head of SNC’s Space Systems. “SNC was able to show NASA that our trajectory analysis and flight performance modeling tools and techniques were able to accurately forecast the flight performance of Dream Chaser from the start of free flight through runway touchdown. Now that we have successfully passed a second flight-based milestone we have further reassurance that our vehicle design is sound and that our spacecraft can successfully fly within established and expected flight boundaries. We are now advancing and upgrading the Dream Chaser test spacecraft in preparation for additional expanded flight tests in 2014.”
During ALT-1, Dream Chaser was outfitted with numerous aerodynamic modeling instrumentation sensors, which provided the Dream Chaser team with a wealth of valuable information relating to the vehicle’s in-flight performance. The results of the ALT-1 post-flight analysis, which was also reviewed by NASA, validated the aerodynamic performance of the Dream Chaser and “significantly matured its aerodynamic database in the subsonic region of flight,” according to SNC.
VIDEO CREDIT: SNCspacesystems
Dream Chaser has proven it can fly autonomously and fly well—at least at sub-sonic speeds—and the Dream Chaser team was able to authenticate that over 40 aerodynamic predictions, from extensive analysis, matched within the limits of the actual vehicle performance.
The Dream Chaser, described by many simply as a “mini space shuttle,” is a lifting body human spacecraft designed to carry as many as seven astronauts, and it is the only spacecraft under the Commercial Crew Development Round 2 (CCDev2) agreement with NASA’s Commercial Crew Program (CCP) that is winged and designed to land on any conventional runway capable of handling commercial traffic.
The company hopes to launch Dream Chaser on its first autonomous orbital spaceflight from Cape Canaveral Air Force Station in Florida in November 2016 atop the proven workhorse United Launch Alliance (ULA) Atlas-V 402 rocket, with the first crewed mission to launch in the third quarter of 2017. SNC intends on operating a fleet of Dream Chasers out of NASA’s Kennedy Space Center, using the space agency’s famed Operations and Checkout Building (known as the O&C) for pre-flight and post-flight Dream Chaser processing, as well as utilizing the three-mile-long shuttle landing facility (SLF) as the spacecraft’s runway of choice when returning home.
The Dream Chaser’s potential as a reusable lifting-body (winged glider) spacecraft is unique—no other company is developing anything similar, nor have those other companies announced any target launch date(s) for their first crewed orbital spaceflights. Dream Chaser will have no abort blackout zones and a 3.5-day free-flight capability—with the added benefit of deorbiting at any time (since Dream Chaser can land on any conventional runway, not just the SLF). The spacecraft will also be able to stay at the International Space Station (ISS) for up to seven months at a time, if needed, before having to return to Earth, and an expected 1.5 G nominal reentry will provide ideal conditions for returning fragile cargo and science experiments, in addition to making the return to gravity easier on the crew (SNC expects immediate access to crew and cargo upon landing). A quick turnaround and an almost entirely reusable vehicle put Dream Chaser in a class all its own.
A second autonomous free-flight test, known as ALT-2, is planned to take place at Edwards AFB again later this year before the company conducts its first piloted Dream Chaser free flight test. No specific date(s) have been announced by SNC for those flights, and we likely will not hear about it until after the flights are conducted (if history is any indication).
To date, SNC has completed over 70 percent of its CCiCap agreement total award value, receiving 100 percent of the milestone value awarded for each milestone completed.