The Boeing challenges and the successes of SpaceX in the Aerospace Safety Advisory Group conference

    Translation of an article from July 30, the original is available by reference .

    As NASA prepares to name the updated launch dates for unmanned and manned demonstration flights under the Commercial Crew program, as well as assign crews for SpaceX and Boeing, the NASA Aerospace Safety Advisory Panel (hereinafter ASAP) advisory group last Thursday held a quarterly meeting. At this meeting, ASAP identified a problem on the part of Boeing that could potentially lead to the redesign of the critical Starliner node. ASAP also highlighted a few positive points about SpaceX.

    Boeing has a Starliner problem

    As Eric Berger first reported to Ars Technica, Boeing failed to test the emergency crew rescue engine at the end of June. During the test, there was a leakage of rocket fuel from the thrust system.

    This was followed by numerous statements from Boeing claiming that they "are confident that they have found the cause and are taking all the necessary steps to eliminate the problem."

    However, this information did not find confirmation at the ASAP meeting, which occurred several days after the company published its statement.

    "Recently, Boeing conducted fire tests for the CST-100 emergency rescue system," said a member of the ASAP group. "And during this test, an anomaly was identified that we need to better understand in terms of its potential impact on the design, performance and schedule (further tests)."

    "And so, despite the increased attention to the topic, Boeing asked for additional time for to study the question from beginning to end and better understand the causes of what happened. "

    During their objectively brief discussion of Boeing, ASAP members did not mention any possible remedial measures, instead indicating that Boeing is still in the process of understanding what exactly caused the malfunction.

    It is possible that ASAP announced the information that it had before the Boeing announcement; however, it is also possible that the group, which is guided by a cautious and balanced approach, still does not have information on the nature of the measures taken to eliminate the problem.

    Regardless of the reasons, ASAP made it clear: the current Boeing plots for both unmanned and manned test launches, known as Orbital Flight Test (OFT) and Crew Flight Test (CFT), respectively, are in a state of uncertainty and not very clear .

    “We can expect some uncertainty in their short-term schedules, at least for Boeing, until they decide on the solution path,” noted ASAP. “And after that, we should have a much better understanding of the state of affairs for OFT and CFT for this operator.”

    This statement says a lot, especially on the eve of the NASA plan to announce new launch dates for OFT and CFT for Boeing (as well as for SpaceX unmanned and manned missions) this Friday, August 3, at an event at the Lyndon Johnson Space Center.

    According to this statement, it becomes clear that the dates for Boeing, which will be announced on Friday, may not be entirely realistic, as the company is still continuing to work on eliminating the consequences and a potential redesign.

    Respect SpaceX, but there is work to do

    Unlike the foregoing, the ASAP group praised SpaceX for a number of areas related to the creation of the manned Dragon and Falcon 9 accelerators, which will be used to launch crews to the International Space Station.

    A separate point was the success of SpaceX in both innovation and adaptability, as well as the development of tracking procedures and programs that greatly assist in system engineering and integration (Systems Engineering & Integration - SE & I) in order to correctly track all design changes and understand how these changes affect the overall design for Crew Dragon and Falcon 9.

    Perhaps the best praise came from an ASAP member who said that “it would be great to have such a thing for the Space Shuttle program” - ASAP member and former NASA astronaut Lieutenant General (Ret.) Susan Helms noted “was surprised the program is evolving, but how SpaceX itself adapts to its use. ”

    “You can never fully understand what the SE & I principles really mean,” commented Lieutenant General (Ret.) Helms. "This means understanding the boundaries of reliability in integrated system projects, being able to make sure that these boundaries really exist through testing and analysis, and then be able to control the configuration and operation of the system to ensure that these boundaries are not crossed in flight, and to what extent all these principles necessary for the culture and practice of production to achieve the best possible results and to ensure the safety of flights into space. ”

    Lieutenant-General (Ret.) Helms also praised SpaceX's “exceptional transparency” with the CCP (Commercial Crew Program) office on all their data ”, including how the tools can help them manage risks.

    "Assuming that the principles of SpaceX will continue to evolve in a similar way, that they will follow the goals of our recommendations, it all looks like a good sign to achieve the goal that was originally set."

    Nevertheless, there were several points (rather than doubts than problems) that ASAP voiced in relation to SpaceX regarding the design of the aircraft.

    One such area is the upcoming change in the supplier providing reef cutters ( reefing line) Parachute Dragon. The original provider chosen by SpaceX was the only NASA certified cutter supplier, and he had to serve Dragon, Starliner and Orion.

    This supplier is an extremely small company that is experiencing problems in ensuring the quantity and, most importantly, the quality of the product supplied due to the increased demand for the three ships under development.

    Thus, SpaceX decided to change the supplier to provide a continuous and high-quality supply of reef cutters. The new supplier is currently undergoing a qualification process, which is nearing completion.

    Currently, SpaceX is in the process of deciding which mission they will use the new supplier’s equipment - the DM-1 unmanned flight or the DM-2 manned mission.

    Parachutes for the DM-1 mission have already been packed in Dragon, and changing reef cutters will delay the flight of the DM-1. SpaceX is actively participating in discussions of risk management issues with ASAP to potentially switch to new reef cutters on the DM-2 manned flight, noting that they are looking forward to the results of these discussions.

    Another area of ​​discussion related to COPVs, Composite Overwrap Pressure Vessels (composite boost tanks) to be used in the Falcon 9 rocket. The new design of the boost tanks will be tested on the unmanned DM-1 mission with the Falcon 9 B1051 as a launch vehicle.

    ASAP stated, “this week we learned a lot about a very detailed and structured approach to the COPV certification used in the SpaceX project. Many tests were conducted, as well as subsequent studies, to try to understand the physics of the process, such as what could cause potential fires and other possible failures. "

    " The team is very grateful to the SpaceX team for the possibility of such a deep immersion, but we acknowledge still a lot of work. The jury has not yet made a decision. We look forward to taking stock and how they will affect the final risk assessment and whether this risk will be acceptable. And if not, what further risk reduction steps may be needed for these COPVs. ”

    Another point to track - the one that, according to ASAP, is on the path to “satisfactory resolution” - concerns the Merlin 1D Falcon 9 engines and their modernization for a manned launch. “The first two engines began to undergo a qualification procedure, and after the analysis some anomalies were discovered that the group considered potentially dangerous - which, of course, is undesirable,” noted ASAP.

    “An attempt was made to change the design and correct these anomalies. SpaceX and NASA agreed on a retraining plan that actually includes six engines — two ground test configurations and one configuration in flight. ”

    As we continue to work on this issue, SpaceX has developed two short-term solutions that are considered worthy and safe for flying in the DM-1 unmanned mission. At the same time, SpaceX began developing and implementing two long-term solutions to eliminate the anomaly observed on the stand.

    ASAP noted that these two short-term solutions can also be potentially used for a DM-2 manned flight, if they prove to be sufficiently safe during dismantling and post-flight inspection and testing. The decision whether these short-term decisions are permissible in a manned demonstration mission will not be made until a better understanding of their effect on reliability is achieved.

    However, ASAP "is optimistic that these actions will lead to a satisfactory solution to the problem."

    Final certification - discussion

    Given all of the above, ASAP expressed satisfaction with the general status of the Commercial Crew program and the fact that both companies are at the finish line in the certification process.

    Separately, it was noted that during the last round of oversight meetings, there was no pressure on the company to keep to the schedule. Both providers were acutely aware that issues related to security and risk factors take precedence over any desire to see results in the case.

    However, “as we approach the certification stage, we still need to be sure that not only the component design of the equipment will be ready for certification, but also that the overall integrated risk of a manned flight can be effectively managed both during hardware design and during use.” equipment, ”noted ASAP.

    In order to clarify this point, one ASAP member took the time to explain in detail what the certification of these products means. During his statements, Dr. Don McArlian tried to explain to everyone what the final certification process entails, since it is often called the “paper process”.

    “Everyone needs to be noted, and we are particularly interested in making sure that all external stakeholders are aware of this, that although the final certification process is sometimes described as a“ paper process, ”it’s nothing but a historically abbreviated reduction. in fact, very far from the truth, "- said Dr. McErlian.

    In fact, the process is as follows. “From the design side, the developer company or the partner in this case performs the design. In terms of certification, the developer company and the certification agency (NASA) agree to submit certification certificates.

    “It can be measurements, it can be test data, it can be analysis, but it almost always involves the presentation of detailed technical data, and not just descriptions or forms. Sometimes this includes checking witnesses for testing, and sometimes it involves physical examinations. But almost always the process is built around important technical issues.

    “The technical division of the certification agency - NASA in this case - then examines and analyzes this data to confirm that the design actually meets the stated requirements with the expected reliability. This validation activity extends to many aspects of the design, as well as the work of the integrated mechanism or the entire system. As soon as the certifying agency agrees that these checks are correct and acceptable, it will certify the project, and only after that we can declare that we have completed the certification process.

    “This technical review of certification data and products is in fact the work required to complete the certification process, and if successful, the agency actually certifies the design.

    “In short, we want everyone to understand that this is not a process of collecting paper signatures. It includes a large amount of detailed technical activity, both by the certification agency - NASA in this case, and by the design and engineering agency or the contractor or partner.

    “In addition, it should be said that the design is certified only for certain operating conditions. This is considered part of the process. And we all understand that, if the operating conditions are significantly expanded, the data must be overestimated and revised to determine whether the project is in line with the new regime.

    “Now we see no prerequisites for changing operating conditions. I'm just talking about it, so that everyone knows that this is so. Thus, the agency and the contractor face a significant amount of detailed technical information, in which the data describing the design itself is checked and evaluated according to the criteria of certification.

    “Once this process is completed, the project will be eligible for certification and will be signed by the certification agency.”

    Thanks to Linsh , striver , amartology , dobrobelko , Lazytech for constructive criticism and suggestions

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