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Cross-‐Waiver/Indemnification Authority (developer of experimental aerospace vehicle) - 42 U.S.C. 2458c
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By NASA
This article is from the 2024 Technical Update.
The NESC evaluated material compatibility of some common aerospace metals in monomethylhydrazine (MMH) and nitrogen tetroxide (MON-3). Previous work had identified a lack of quantitative compatibility data for nickel alloy 718, 300 series stainless steel, and titanium Ti-6Al-4V in MMH and MON-3 to support the use of zero-failure-tolerant, thin-walled pressure barriers in these propellants. Static (i.e., not flowing) general corrosion and electrochemistry testing was conducted, evaluating varied processing forms and heat treatment of the metals, water content of propellant, and exposure duration. Corrosion-rate data for all tested product forms, fluids, and durations were on the order of 1 x 10–6 inch per year rather than the previously documented “less than 1 x 10–3 inch per year”. The majority of the corrosion products were seen in the first 20 days of exposure, with an overall corrosion rate decreasing with time due to the increased divisor (time). It is therefore recommended that corrosion testing be performed at multiple short-term durations to inform the need for longer-duration testing.
Background
Nickel alloy 718, 300 series stainless steel, and Ti-6Al-4V are commonly used in storable propulsion systems (i.e., MMH/MON-3), but a concern was raised regarding what quantitative compatibility data were available for proposed zero-failure-tolerant, thin-walled (~0.005 to 0.010 inch thickness) pressure barrier designs. A literature search found that limited and conflicting data were available for commonly used aerospace metals in MMH and MON-3. For example, corrosion behavior was listed qualitatively (e.g., “A” rating), data on materials and fluids tested were imprecise, fluids were identified as contaminated without describing how they were contaminated, no compatibility data were found on relevant geometry specimens (i.e., very thin-walled or convoluted), and limited data were available to quantify differences between tested materials and flight components. When corrosion data were quantified, documented sensitivity was “1 x 10–3 inch per year or less”, which is insufficient for assessing long-duration, thin-walled, flight-weight applications.
Discussion
General corrosion testing was performed with a static/non-flowing configuration based on NASA-STD-6001, Test 15 [1]. Design of experiments methods were used to develop a test matrix varying material, propellant, propellant water content, and tested duration. Materials tested were nickel alloy 718 (solution annealed sheet, aged sheet, aged/welded sheet, and hydroformed bellows), 300 series stainless steel (low carbon sheet, titanium stabilized sheet, and hydroformed bellows), and Ti 6Al-4V sheet. Samples were tested in sealed test tubes in MMH and MON-3 with water content ranging from as-received (“dry”) up to specification allowable limits [2,3]. Tested durations ranged from 20 to 365 days. Measurements included inductively coupled plasma mass spectrometry (ICPMS) to identify corrosion products and their concentrations in test fluid, gravimetric (i.e., scale) measurements pre- and post-exposure, and visual inspection. Bimetallic pairs (titanium stabilized 300 series stainless steel: Ti 6Al-4V and nickel alloy 718: Ti 6Al-4V) were tested for up to 65 days in both MMH and MON-3. The test setup incorporated important features of the test standard (e.g., electrode spacing and finish) and adapted the configuration for MMH/MON-3 operation. Measurements included potential difference and current flow between samples. Figure 1 shows images of the general corrosion and bimetallic pair test setups.
Test Results
For all tested materials and product forms, corrosion rates were on the order of 1 x 10–6 inch per year in MMH or MON-3, three orders of magnitude lower than historically reported. Corrosion products were generated in the first 20 days of exposure, and corrosion rate decreased with time due to the increase in divisor (i.e., time). Corrosion products increased as the water content of the propellants increased but remained in the same order of magnitude between the as-received dry propellant and propellant containing the maximum water content allowed by specification. Figure 2 illustrates test results for corrosion rate, mass loss with duration, and mass loss with water content. It is important to note that water has been demonstrated to contribute to flow decay even when water is within the specification allowable limit, and previous NASA-STD-6001 Test 15 data have demonstrated susceptibility of some nickel alloys to crevice-type corrosion attack [4]. Therefore, these results do not reduce the importance of considering the system impact of water content and evaluating for crevice corrosion behavior. Finally, in the bimetallic pair testing, tested materials did not measurably corrode in MON-3 and MMH within specification-allowable water content, as evidenced by no visual indications of corrosion and very low electrical interaction (i.e., corrosion rates derived to be less than 1 microinch per year from electrical interaction).
Recommendations
It is recommended that corrosion testing be performed at multiple shortterm durations to inform the need for longer-duration testing.
References
NASA-STD-6001 Flammability, Odor, Offgassing, and Compatibility Requirements
and Test Procedures for Materials In Environments that Support Combustion MIL-PRF-27404 Performance Specification: Propellant, Monomethylhydrazine MIL-PRF-26539 Performance Specification: Propellants, Dinitrogen Tetroxide WSTF Test 15 Report 12-45708 and WSTF Test 15 Report 13-46207 View the full article
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By NASA
Media are invited to learn about a unique series of flight tests happening in Virginia in partnership between NASA and GE Aerospace that aim to help the aviation industry better understand contrails and their impact on the Earth’s climate. Contrails are the lines of clouds that can be created by high-flying aircraft, but they may have an unseen effect on the planet – trapping heat in the atmosphere.
The media event will occur from 9 a.m.-12 p.m. on Monday, Nov. 25 at NASA’s Langley Research Center in Hampton, Virginia. NASA Langley’s G-III aircraft and mobile laboratory, as well as GE Aerospace’s 747 Flying Test Bed (FTB) will be on site. NASA project researchers and GE Aerospace’s flight crew will be available to discuss the Contrail Optical Depth Experiment (CODEX), new test methods and technologies used, and the real-world impacts of understanding and managing contrails. Media interested in attending must contact Brittny McGraw at brittny.v.mcgraw@nasa.gov no later than 12 p.m. EST, Friday, Nov. 22.
Flights for CODEX are being conducted this week. NASA Langley’s G-III will follow GE Aerospace’s FTB in the sky and scan the aircraft wake with Light Detection and Ranging (LiDAR) technology. This will advance the use of LiDAR by NASA to generate three-dimensional imaging of contrails to better characterize how contrails form and how they behave over time.
For more information about NASA’s work in green aviation tech, visit:
https://www.nasa.gov/aeronautics/green-aero-tech
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David Meade
Langley Research Center, Hampton, Virginia
757-751-2034 davidlee.t.meade@nasa.gov
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By NASA
Name: Matthew Kowalewski
Title: Dragonfly Mass Spectrometer (DraMS) Lead Instrument Systems Engineer
Formal Job Classification: Aerospace Engineer
Organization: Instrument and Payload Systems Engineering Branch (Code 592)
Matthew Kowalewski is the lead instrument systems engineer for NASA’s Dragonfly Mass Spectrometer (DraMS). Photo courtesy of Matthew Kowalewski What do you do and what is most interesting about your role here at Goddard?
As the DraMS lead instrument systems engineer for NASA’s Dragonfly mission, I lead the coordinated technical development, integrating systems and making sure communications across subsystems is maintained within the instruments as well as with the lander. I enjoy the diversity and complexity of this instrument.
What do you enjoy most about your current position as the DraMS lead instrument systems engineer?
I started this position in March 2023 and it has been like drinking from a fire hose ever since, but in a good way. The complexity of the instrument and the number of subsystems means this is really three separate instruments in one, and that makes my job exciting. I have to keep up with a range of disciplines across everything that Goddard does including mechanisms, lasers, mass spectrometers, gas flow systems, mechanical systems, thermal systems and electrical systems.
I am always challenged and excited by those challenges too. Everything we do is necessary to meet the broad science requirements. Our goal is studying prebiotic chemistry on the surface of Titan.
What is your educational background? Why did you become an aerospace engineer?
I have a B.A. in astronomy and physics from Boston University and a master’s in physics from Johns Hopkins University.
As a child, I was more interested in astronomy and physics. In college, I developed an extreme interest in experimental physics including the engineering required to perform these experiments.
How did you come to Goddard?
After college, I worked in missile defense for a private company supporting the Midcourse Space Experiment. After three years, in 1998, my wife and I wanted to move closer to family, so I came to Goddard as an instrument engineer supporting the Total Ozone Mapping Spectrometer-Earth Probe (TOMS/EP) mission. I have also supported the Ozone Monitoring Instrument on Aura, The Ozone Mapping Profiler Suite (OMPS) on Suomi NPP and JPSS, various airborne field campaigns, and the New Opportunities Office.
What interesting field work did you do prior to joining DraMS?
I largely did field work supporting Earth science research and new business development. We flew remote sensing instruments on high altitude aircraft in the United States, Costa Rica, South Korea [whose official name is the Republic of Korea], and Canada. Most field campaigns lasted about a month where we were housed in hotels or military bases. While supporting the New Opportunities Office, we developed instrument and mission concepts, evaluated and prioritized technologies, and fostered relationships with industry, universities, and other government organizations.
How do you lead across multiple teams?
I lead a large team engineers and technicians spanning across over six teams. Communication is the key. I rely on the expertise of our systems team and all of the subsystem leads. We have daily and weekly meetings where everyone is heard and they are free to approach me whenever they have concerns.
I try to encourage open discussions including contrarian thoughts and ideas. I listen to all the options and opinions in an attempt to make the best-informed decision. Then I move forward with my decision.
In a cost- and schedule-constrained environment, like most missions are, we cannot get stuck in the decision-making process. At some point, a decision needs to be made and the team then moves forward.
Where have you traveled for work?
I have been to multiple NASA centers and military bases in this country. In addition to Costa Rica, South Korea and Canada, I have also been to the Netherlands and France for mission development.
What is the most memorable moment you have had at Goddard?
In 2003, I was supporting the space shuttle Columbia mission, STS-107. We had a small payload in the shuttle cargo bay called a Hitchhiker. I was second shift in the Hitchhiker mission operations center. I got to interact with the astronauts both prelaunch and on orbit. It meant a lot to me. My last shift was just prior to their reentry. It really impacted me when I learned, after my shift, that the shuttle disintegrated with all hands lost.
I had the honor of meeting these astronauts. It reminded me of the importance of the work that we do as we continue sending astronauts into orbit for missions.
When you mentor someone, what do you advise them to do?
I tell them to learn as much about everything that they can. For example, if they are an engineer, they should learn about science and other disciplines because a broad knowledge base will help them in the future. They will also learn why building a small piece of hardware is important for accomplishing the mission’s science goals. An electrical engineer building a circuit is actually building something for a far larger purpose.
It is also very important to get along with others. We work with others every day, in all aspects of our lives, and we have to understand their perspectives and respect their opinions. There is more to our jobs than building things. Establishing relationships with others is what truly allows us to accomplish our goals.
What do you do for fun?
I have four kids and enjoy spending time with them. I coach soccer, mentor a robotics club, and participate in endurance swim races. This is my second year as a mentor to my son’s robotics club, which participates in an annual, national robotics competition to build a robot from scratch. This year we have a highly mobile, fast robot with a multi-jointed arm to manipulate objects. I think we have a good shot at going to nationals.
Who would you like to thank?
I wish to thank my wife Angie for supporting me over all these years as my career developed. She was often home alone with four kids during long stints of travel. I would not be where I am without her.
I also owe much to my mentors, Scott Janz, Glenn Jaross, and Jay Al-Saadi for all their guidance, support and opportunities over the many years. Nobody can work alone, no matter how smart you are.
What is your “five-word or phrase memoir”? A five-word or phrase memoir describes something in just five words or phrases.
Understanding. Compassionate. Persistent. Hard-working. Curious about too many things.
By Elizabeth M. Jarrell
NASA’s Goddard Space Flight Center, Greenbelt, Md.
Conversations With Goddard is a collection of Q&A profiles highlighting the breadth and depth of NASA’s Goddard Space Flight Center’s talented and diverse workforce. The Conversations have been published twice a month on average since May 2011. Read past editions on Goddard’s “Our People” webpage.
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Last Updated Nov 12, 2024 EditorRob GarnerContactRob Garnerrob.garner@nasa.govLocationGoddard Space Flight Center Related Terms
People of Goddard Dragonfly Goddard Space Flight Center People of NASA View the full article
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By NASA
In the ever-evolving aerospace industry, collaboration and mentorship are vital for fostering innovation and growth. Recent achievements highlight the positive impact of Mentor-Protégé Agreements (MPA) facilitated by Jacobs Engineering Group, now known as Amentum Space Exploration Group. Two standout partnerships have demonstrated remarkable success and expansion, underscoring the value of such initiatives.
CODEplus and Amentum Space Exploration Group
The 24-Month MPA between CODEplus and Amentum Space Exploration Group has proven to be a game-changer. Recognized as the FY24 Marshall Space Flight Center (MSFC) Mentor-Protégé Agreement of the Year, this collaboration has significantly boosted CODEplus’s operations. Since the agreement’s inception on March 1, 2023, CODEplus has expanded its workforce to ten full-time employees and currently has two active job requisitions. This growth exemplifies the transformative potential of mentorship in nurturing small businesses within the aerospace sector.
KS Ware and Amentum Space Exploration Group / CH2M Hill
Another exemplary partnership involves KS Ware, which has benefitted from a 36-Month MPA with Amentum Space Exploration Group and CH2M Hill. This agreement has garnered accolades as both the FY23 NASA Agency Mentor-Protégé Agreement of the Year and the FY23 MSFC Mentor-Protégé Agreement of the Year. Through targeted business and technical counseling, KS Ware successfully launched a new drilling division in 2022 and expanded its offerings to include surveying services in 2023. The impact of this mentorship is evident, with a remarkable 30% growth rate reported for KS Ware.
These success stories highlight the critical role of Mentor-Protégé Agreements in empowering small businesses in the aerospace industry. By fostering collaboration and providing essential support, Amentum Space Exploration Group has not only strengthened its partnerships but also contributed to the broader growth and innovation landscape. As the aerospace sector continues to evolve, such initiatives will be essential in driving future success.
Published by: Tracy L. Hudspeth
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By NASA
NASA NASA pilot Joe Walker sits in the pilot’s platform of the Lunar Landing Research Vehicle (LLRV) number 1 on Oct. 30, 1964. The LLRV and its successor the Lunar Landing Training Vehicle (LLTV) provided the training tool to simulate the final 200 feet of the descent to the Moon’s surface.
The LLRVs, humorously referred to as flying bedsteads, were used by NASA’s Flight Research Center, now NASA’s Armstrong Flight Research Center in California, to study and analyze piloting techniques needed to fly and land the Apollo lunar module in the moon’s airless environment.
Learn more about the LLRV’s first flight.
Image credit: NASA
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