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Posted 15 March 2012 - 22:52
Posted 16 March 2012 - 10:42
Posted 17 March 2012 - 14:51
SPACEX COMPLETES IMPORTANT COMMERCIAL CREW MILESTONE | ENTER THE DRAGON--PLEASE TAKE YOUR SEATS
SpaceX continues to prepare for our upcoming test flight in which we will attempt to send the Dragon spacecraft to the International Space Station. At the same time we continue making rapid progress in our efforts to prepare the Dragon spacecraft to carry astronauts.
You may have read our update on the initial tests of the SuperDraco engines that will power the launch escape system. Recently, SpaceX completed another important milestone – the first NASA Crew Trial, one of two crew tests as part of SpaceX’s work to build a prototype Dragon crew cabin.
For this milestone SpaceX demonstrated that our new crew cabin design will work well for astronauts in both nominal and off-nominal scenarios. It also provided our engineers with the opportunity to gain valuable feedback from both NASA astronauts and industry experts.
SpaceX and NASA conducted a daylong review of the Dragon crew vehicle layout using the Dragon engineering model equipped with seats and representations of crew systems. Photo: SpaceX
The engineering prototype includes seven seats as well as representations of crew accommodations such as lighting, environmental control and life support systems, displays, cargo racks, and other interior systems. During the daylong test, SpaceX and NASA evaluators including four NASA astronauts, participated in human factors assessments which covered entering and exiting Dragon under both normal and contingency cases, as well as reach and visibility evaluations.
Test crew included (from top left): NASA Crew Survival Engineering Team Lead Dustin Gohmert, NASA Astronaut Tony Antonelli, NASA Astronaut Lee Archambault, SpaceX Mission Operations Engineer Laura Crabtree, SpaceX Thermal Engineer Brenda Hernandez, NASA Astronaut Rex Walheim, and NASA Astronaut Tim Kopra. Photo: Roger Gilbertson / SpaceX
The seven seats mount to strong, lightweight supporting structures attached to the pressure vessel walls. Each seat can hold an adult up to 6 feet 5 inches tall, 250 lbs, and has a liner that is custom-fit for the crewmember.
With all seven crewmembers in their seats, Dragon has sufficient interior space for three additional people to stand and assist the crew with their launch preparations.
NASA Astronaut Rex Walheim, SpaceX CEO and Chief Designer Elon Musk and SpaceX Commercial Crew Development Manager and former NASA Astronaut Garrett Reisman standing inside the Dragon spacecraft during testing activities.
In fact, Dragon has so much interior volume, that we could place an entire three-person Russian Soyuz capsule descent module inside Dragon’s pressure vessel.
Stay tuned for more updates as we work towards making Dragon the most advanced spacecraft ever flown.
Posted 19 March 2012 - 12:28
NASA ADVISORY COUNCIL (NAC)
NASA Headquarters October 31-November 1, 2011
The Feasibility of a Dragon-derived Mars lander for scientific and human-precursor investigation
John Karcz, Ames Research Center
John Karcz said the starting point for his group's work had been the recognition that it might be possible to take advantage of the commercial spacecraft now in development to be able to do more with a Discovery class budget. The SpaceX capsule, he said, would be used to take people to low-earth orbit; SpaceX would have most of the capabilities needed to put material on Mars. He reported that SpaceX developers had been thinking along these lines. He believed that a substantially unmodified version of the crewed capsule intended for the International Space Station (ISS) could be used for payload transport to Mars. Currently, he said, the 'Icebreaker' concept was a drilling mission that would penetrate a meter or more into the Martian regolith. He noted that Dragon was a dense spacecraft; that is, it had a high ballistic coefficient. He believed Dragon could be used to deliver payloads of one ton or more to the Martian surface. He added that drag must slow the capsule sufficiently for the remainder of descent to be within the propulsion system capabilities.
Scott Hubbard said he thought propulsive entry into the Martian atmosphere was very difficult; all Martian missions to date had used a parachute to slow the rate of descent. John Karcz said the primary technical question was whether Dragon could perform all the necessary EDL (Entry Descent and Landing) functions. He believed a retro-propulsive descent would be possible as the basic approach.
Regarding costs, Dr. Karcz said that SpaceX estimates a cost of $150 million to $190 million for a launch vehicle and lander. The Dragon already has most of the necessary capabilities: sufficient lifetime and resources for a Mars transfer trajectory; atmospheric entry systems capable of guided lifting and highly capable retro-propulsion thruster. Falcon Heavy, he noted, could throw Dragon to Mars. He also noted that Dragon offers a large interior volume. He believed the EDL technology was scalable to large cargo and human landers. Assuming launch by Falcon Heavy, he said, the trunk would separate nears Mars; the capsule would decelerate through retro-propulsive action. The version under discussion would land on its legs.
Larry Lemke, Ames Research Center, said what was foreseen was both similar to and different from other landings. Ballistic coefficient and lift-to-drag determine the change in speed during the dissipative portion of entry. Basically, he said, Dragon's entry characteristics were in the middle of the spectrum of 'where we have been and where we wish to go'-between previous landers and future human-scale landers. Dr. Tapley asked what proportion of the deceleration would be performed retro-propulsively. Lemke said that retro-propulsion would start at supersonic speeds. This approach, he stated, should make it possible to land the capsule at much higher Martian elevations than could be done if a parachute was used. Professor Hubbard asked what sites were being considered; Dr. Karcz said all contemplated sites were in the northern hemisphere. He noted that retro-propulsion had been studied by NASA for human landings.
Addressing current results (slide #12), Dr. Karcz said that a few point cases for EDL had been examined and that they had explored various alternatives around the nominal cases, and that the group was very comfortable that it could put down more than a ton of payload on the selected landing site. He reported that the EDL 'looked okay' at least for the missions under consideration. Other work was continuing: for example, on how to integrate the payload to Dragon.
Dr. Huntress said it was a very interesting concept to pursue, particularly as a human precursor and even as a Discovery concept. He asked if any notion had been developed as to how this could address the decadal recommendations for Mars. Karcz said his group had engaged in preliminary discussion, but had not examined the possibilities carefully. A second team member said that if one considered sample return missions, he doubted a Dragon capsule could do everything one would want. Huntress asked if the group had 'pitched this approach to the human side' of the house. Karcz said the approach addressed a number of matters that the human effort would need to address. Conversation returned to the method of descent. Karcz said the angle of attack in landing would not be controllable; however, the length of the flight path could be altered by rolling and banking. Extending the 'flight path' of descent would in effect, compensate for adjustments in speed. Professor Hubbard asked how the payload would be moved from inside to outside the capsule. This drew the comment that the vehicle had 'a big hatch.' It was noted that the presentation had made reference to a 2006 analysis by Braun and Manning; in response to a question, John Karcz said he had not spoken directly to the authors.
Posted 20 March 2012 - 03:46
Posted 20 March 2012 - 04:52
Posted 24 March 2012 - 16:08
Boeing, SpaceX satellite deals provide boost to Southland
In an estimated $1-billion boost to the Southland aerospace industry, satellite maker Boeing Co. and rocket firm Space Exploration Technologies Corp., better known as SpaceX, announced plans to build and launch four satellites for telecommunications firms in Mexico and Hong Kong.
The companies' joint satellite order will help preserve high-paying engineering jobs in the South Bay and throws a lifeline to hundreds of smaller aerospace suppliers feeling an economic pinch with Pentagon and NASA budget cuts on the horizon.
In El Segundo, Boeing will build four minivan-size communication satellites in its million-square-foot complex near Los Angeles International Airport. In nearby Hawthorne, SpaceX makes its 18-story Falcon 9 rockets at a sprawling facility that once housed construction on 747 jumbo jet fuselage sections.
The rocket and satellites will be shipped to SpaceX's launch pad in Cape Canaveral, Fla., for launch in late 2014 or early 2015, the companies said.
The deals, announced Tuesday, were made in a joint procurement by regional satellite operators Asia Broadcast Satellite of Hong Kong and Satélites Mexicanos of Mexico City.
"Winning an international contract like this really speaks to the competitiveness and innovation of Southern California," said Elon Musk, SpaceX's chief executive and chief technology officer. "It means about $1 billion in revenue will come to L.A."
Craig R. Cooning, general manager of Boeing's space and intelligence systems, also recognized the contracts' importance to the region.
"We're two companies that have been adaptive to the changing marketplace," he said.
For Boeing, the deal represents the first sale of its new 702SP satellite. The spacecraft is a smaller version of the 702HP satellite that the company has sold to the Pentagon and communications giants such as DirecTV.
At launch time, the 702SP will weigh just under 4,000 pounds, as opposed to 13,000 pounds for the larger satellite.
Posted 26 March 2012 - 22:03
Posted 16 April 2012 - 12:50
Posted 16 April 2012 - 19:14
Posted 18 April 2012 - 23:51
SpaceX and NASA are moving ahead with the scheduled April 30 launch date of the Dragon spacecraft and its historic docking with the International Space Station after the flight readiness review was approved at the Johnson Space Center in Houston, Texas.
The comprehensive evaluation of the SpaceX mission is one of the last major steps before the company becomes the first commercial carrier to deliver payloads to the ISS. Although SpaceX founder and chief designer Elon Musk was careful to remind everybody that the flight is a test and success is far from guaranteed.
(EDIT: talking head stuff)
The mission will take roughly four days until the Dragon will dock with the space station in orbit and combines two separate tests into a single flight. The capsule will then remain attached to the station for 18 days. The first demonstration test will be a flight around the space station to test and verify maneuverability, navigation and communication capabilities.
On flight day three, the Dragon spacecraft will begin a series of maneuvers that will take it on a lap around the ISS beginning with a relatively close 2.5-kilometer (1.5-mile) pass underneath the station. During this close pass the Dragon and the ISS will communicate with each other for the first time. “An absolute requirement for proximity operations,” according to NASA flight director Holly Ridings.
The crew on board the space station will send a test command to Dragon to confirm those on the ISS have the ability to control the capsule when necessary. The communication tests are to make sure the crew would be able to command the Dragon to hold or abort if needed when it is in close proximity to the station.
After the 2.5 km pass, the Dragon will move out to 200 km as it continues the lap. It will then again maneuver closer as it passes over the top of the station, this time getting as close as 7 km. The entire lap should take a full day, 22-24 hours according to Ridings.
On flight day four, the Dragon will once again be guided to 2.5 km underneath the station as preparations are made for the final tests before finally docking with the ISS. Once inside this 2.5 km zone, Ridings says the NASA team in Houston has final authority over the mission due to the proximity to the station and the safety of the crew on board.
The next parking spot will be at 1.4 km as the Dragon prepares for the approach initiation. Once everybody agrees for a go, the Dragon will maneuver to a point just 250 meters (820 feet) from the station, which will serve as its hold point for the final tests in very close proximity to the station. According to NASA, the hold point is outside the critical KOS, the acronym-happy agency’s simply named “Keep Out Sphere.”
The next demonstration objectives include interaction with the crew on orbit. From the 250 m hold point, the Dragon team at SpaceX’s Hawthorne, California headquarters will issue a command to slowly begin approaching the station, after which the ISS crew will issue a retreat command as the first test. The demonstration will be repeated, this time with the ISS crew issuing a hold command at 220 m.
“That will be the last of our go/no go objectives in terms of the demonstration objective,” according to Ridings.
After these demonstrations are complete and everybody at NASA and SpaceX are satisfied, the Dragon will then make the final maneuvers towards the station. With all the functionality of the Dragon checked out, the spacecraft will be commanded by the SpaceX team to cross the KOS boundary for the first time.
The Dragon will then stop at 30 m, where the go/no-go decision will be made by everybody on the ground as well as the crew on the station to make the final approach. Though the Dragon is an automated spacecraft and is capable of performing the entire mission autonomously, Ridings emphasized that the station crew will be heavily involved and is there as a safety net, especially on the first flight.
After maneuvering to just 10 m from the station, the Dragon will park in its final hold position, known as the capture point. Once a final decision is made for capture, the station crew takes over the final steps using the robotic arm to reach out and grab the Dragon and move into its berthing spot on the station.
The final step of the mission from the 2.5 km point to docking is expected to take around seven to eight hours. On the following day, the station crew begins the laborious cargo transfer as 521 kilograms (1,146 pounds) are offloaded from the Dragon, and 660 kilograms (1,452 pounds) of cargo from the station are placed into the capsule to be returned to earth. Thankfully, it’s mostly the motions that are laborious and not heavy lifting.
Representatives from the NASA side of the review meeting also reminded reporters of the test nature of the mission. But all sounded confident based on the preparation, simulations and tests that have been completed. NASA space station program manager Mike Sufferdini told reporters there are still some verifications that need to be done, but everything is looking good.
Sufferdini said the past few years has been a positive learning experience for both organizations and he’s excited to see a new vehicle arrive at the station. One of the differences during the flight readiness review he pointed to compared to past NASA missions is the bottom line. “There were no requirements for mission success,” he said. The simple comment in many ways marks NASA’s transition from shouldering the responsibility to deliver payloads to orbit, to a consumer of space delivery services. This point is driven home as today marks the last flight of the space shuttle discovery as it was flown to Washington, D.C., where it will be handed over to the Smithsonian.
SpaceX has one more launch simulation to complete before the launch. Sufferdini said there are some verifications that still need to be completed, but nothing that indicates there should be any issues.
Posted 03 June 2012 - 23:58
Posted 04 June 2012 - 09:44
Posted 26 June 2012 - 13:05