Quote from: FutureSpaceTourist on 04/29/2020 10:15 pmOuch-snip-This isn't an SLS problem, this is a hydrogen problem.With Shuttle Back in Space, NASA Returns to Leak ProblemHYDROGEN LEAKS TORMENT NASA
Program officials indicated that one of the top remaining technical risks to the green run test is that the core stage may develop leaks when it is filled with fuel. According to these officials, they have conducted extensive scaled testing of the gaskets and seals used in the core stage; however, it is difficult to precisely predict how this large volume of liquid hydrogen will affect the stage.
Gateway - Deep Space Logistics : SpaceX may be given authority to proceed on first mission in late 2023. First Dragon XL flight currently planned for 2027, delivering Gateway External Robotic System (GERS).HALO : "preliminary launch schedule from July 2025 to February 2026" "As of February 2022, the co-manifested vehicle is above the Falcon Heavy launch vehicle’s mass limit. If the mass is too high, it could affect the vehicle’s ability to reach the correct lunar orbit. The project is taking steps to reduce mass, including evaluating whether it needs to potentially off-load some components for initial launch."HLS : "The program is reviewing initial schedules from SpaceX, and expects to establish cost and schedule baselines in August 2022."Dragonfly : "NASA’s Launch Services Program provided the project with performance information on the candidate heavy-lift launch vehicles: Falcon Heavy, Vulcan 6s, and New Glenn."CCP : Crewed Flight Test. CCP and Boeing have multiple items to complete to be ready for the crewed flight test. While launch vehicle components have been delivered and Boeing requested a launch window, the service module production will be a key schedule driver. Boeing will fly the service module originally slated for its first service mission on its crewed flight test. CCP and Boeing’s readiness for the crewed flight test will be determined by how quickly they complete the significant certification work that remains. The CCP program manager said the program approved 50 percent of Boeing’s certification products for the crewed flight test as of January 2022. However, because the program limited the scope of uncrewed flight test-2 to reduce the program’s certification workload, the program manager said the remaining certification work for the crewed flight test includes challenging items such as Boeing’s parachutes, landing loads, and abort systems.In addition, the CCP and ISS programs are concerned that operational staff may not be able to safely operate Boeing’s crewed spacecraft if there are any issues with Boeing’s flight software. CCP reported that Boeing’s approach to software development and testing created a significant backlog of software problem reports. Program officials said the operations team is being trained on operational workarounds to complete functions manually that software would normally automate. Several teams reported little capacity to safely accommodate additional operational workload that may be needed if there are any problems with Boeing’s flight software. To mitigate this issue, CCP plans to provide operational teams 6 months of training time with released software and closely monitor workload.One of CCP’s top risks for the crewed flight test is that quality issues with hardware may pose unknown risks to the mission or to crew safety. CCP had previously discovered deficiencies in Boeing’s quality management of its suppliers. Boeing made changes to its quality management processes, which NASA determined to be sufficient through multiple audits. However, CCP plans to conduct technical assessments of certain systems to better understand the risk level to the mission or crew safety.Europa Clipper : Launching on a Falcon Heavy during the project’s target launch date of October 2024 will require that Europa Clipper fly first around Mars and Earth—leveraging the planets’ gravities to increase the spacecraft’s speed in a maneuver known as a gravity assist—before entering Jupiter’s orbit in April 2030. If the project does not meet the target launch date, the next launch opportunity begins in October 2025. This later date would require Europa Clipper to execute two Earth and one Mars gravity assists before entering Jupiter’s orbit in July 2031.
Psyche uses two specialized cameras, or imagers, for science imaging and spacecraft navigation. The imagers include parts such as a telescope and camera electronics. The imagers continue to face technical challenges, and one is further in development than the other. The fundamental problem is the sensitivity of the primary mirror within the telescope to distortions in the mirror’s surface caused by external stresses over temperature. For example, the structure and bond materials that hold the mirror in place could distort the surface of the mirror, resulting in poor performance. In addition, one imager did not behave the way models predicted. Because of these issues, the telescopes had to be disassembled and reassembled several times. The project is working to mitigate these issues by replacing hardware and using different materials and bonding techniques.