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NASA NTRS2018

Flight and Ground Operations in Support of Airframe Noise Reduction Tests

The National Aeronautics and Space Administration (NASA) Acoustic Research Measurements (ARM) project was established to evaluate via flight tests the noise reduction benefits of the Adaptive Compliant Trailing Edge (ACTE) technology along with various main landing gear noise reduction concepts. The ACTE replaces the original Fowler flaps on the NASA SubsoniC Research Aircraft Testbed (SCRAT), thus creating a seamless trailing edge that provides significant noise abatement benefits. The various main landing gear noise reduction concepts are grouped under the LAnding Gear noisE Reduction (LAGER) task and consist of fairings placed on the main landing gear along with two separate treatments applied to the main landing gear wheel well cavities. This paper discusses the tasks necessary to prepare each of these technologies for the ARM flights. The LAGER hardware was taken from model-scale concepts tested in wind tunnels to flight hardware, which had to be cleared as airworthy for the ARM flights. The ACTE flaps were initially intended to be removed from the SCRAT prior to the start of the ARM project. Retaining the ACTE flaps on the aircraft for a longer period of time to support the ARM flights resulted in additional inspections and considerations since the ACTE flaps were flown longer and at certain flight conditions for longer periods of time than initially analyzed. The flight and ground operations required for the ARM tests required extensive coordination among multiple groups and organizations in order to be successful. This paper provides an overview of the hardware development, ground operations, and flight operations which went into acquiring the desired acoustic measurements. In general, the flights were successful and demonstrated the noise reduction benefits of the ACTE flaps, the LAGER gear fairings, and the LAGER gear cavity treatments.

ground operations↗
NASA NTRS2018

An Overview of Lessons Learned from Sonic-boom Flight Research Projects Conducted by NASA Armstrong Flight Research Center

Over the course of four years, a team of aerospace engineers at the National Aeronautics and Space Administration Armstrong Flight Research Center completed four projects, each with the objective to research sonic-boom signatures from a ground-and building-level perspective. The relatively compressed timeline of these projects resulted in many lessons learned. With each successive project, these lessons have been more relied upon and referenced. This paper provides a high-level overview of the teams relevant lessons learned and the importance of these lessons for future projects.

lessons learned↗
NASA NTRS2018

Aseptic Operations for Post DHMR Processing of MOMA Mass Spectrometer

Mars Organic Molecule Analyzer - Mass Spectrometer (MOMA-MS) is an instrument in the MOMA instrument suite for the European Space Agency (ESA) ExoMars 2020 Rover. The rover is Planetary Protection Mission Category IVb, the first IVb mission since the Viking missions in the 1970s. Within the sample path of the MOMA instrument suite, the hardware surfaces of the must be sanitized to a level of less than 0.03 spore/m sq. To meet this requirement, the MS sample path was subjected to Dry Heat Microbial Reduction (DHMR) to decrease the number of viable spores by 4 orders of magnitude from a measured 88 spores/m sq to 0.009 spores/m sq. Before DHMR, the hardware is handled using standard cleanroom practices. After DHMR, planetary protection filters protect the sample path for most of integration, but when sample path exposure is required, aseptic operations are instituted and exposure times are kept to an absolute minimum. The surface area of exposure is also taken into account to determine safe exposure times. Before work begins, the ISO class 5 aseptic workspace is cleaned and tested for surface and airborne bioburden, and all tools that will contact or be used near sample path surfaces are sterilized. During the exposure activity, sterile garments are worn, sterile gloves are changed as often as necessary, and the environment is monitored with active and passive fallout for bioburden and real time airborne particle counts. Sterile tools are handled by a two person team so that the operator touches only the tool and not the exterior surfaces of the sterilization pouch, and a sterile operating field is established as a safe place to organize tools or parts during the aseptic operations. In cases where aseptic operations are not feasible, localized DHMR is used after exposure. Any breach in the planetary protection cleanliness can necessitate repeating instrument level DHMR, which not only has significant cost and schedule implications, it also become a risk to hardware that is not rated for repeated long exposures to high temperatures.

Spacecraft Design↗
NASA NTRS2018

Development and Implementation of Aseptic Operations for the MOMA-Mass Spectrometer

The ExoMars 2020 Rover is a life detection mission, and is classified as Planetary Protection (PP) Mission Category IVb, the first IVb mission since the Viking missions. Mars Organic Molecule Analyzer Mass Spectrometer (MOMA-MS) is a life detection instrument for the rover. To meet the stringent bioburden requirement of 0.03 spore/m2, the MS is subjected to Dry Heat Microbial Reduction (DHMR) to decrease the bioburden from a measured 88 spores/m2 to 0.009 spores/m2. After DHMR, exposure of the sample path must be kept to an absolute minimum and requires aseptic operations. Aseptic operations include determining the safe exposure time based on the surface area of exposure and particle fallout expected in the aseptic ISO class 5 workspace, preparing an aseptic ISO class 5 workspace, and using sterile garments and tools. During the exposure activity the environment is monitored with active and passive fallout for bioburden and real time airborne particle counts. Sterile tools are handled by a two person team so the operator touches only the tool and not the exterior surfaces of the sterilization pouch, and a sterile operating field is established as a safe place to organize tools or parts during the aseptic operations. In cases where aseptic operations are not feasible, localized DHMR is used after exposure. Any breach in the PP cleanliness can necessitate repeating instrument level DHMR, which not only has significant cost and schedule implications, but also is a risk to hardware that is not rated for repeated long exposures to high temperatures.

Aseptic processing↗
NASA NTRS2018

Considerations in Assuring Safety of Increasingly Autonomous Systems

Recent technological advances have accelerated the development and application of increasingly autonomous (IA) systems in civil and military aviation. IA systems can provide automation of complex mission tasks-ranging across reduced crew operations, air-traffic management, and unmanned, autonomous aircraft-with most applications calling for collaboration and teaming among humans and IA agents. IA systems are expected to provide benefits in terms of safety, reliability, efficiency, affordability, and previously unattainable mission capability. There is also a potential for improving safety by removal of human errors. There are, however, several challenges in the safety assurance of these systems due to the highly adaptive and non-deterministic behavior of these systems, and vulnerabilities due to potential divergence of airplane state awareness between the IA system and humans. These systems must deal with external sensors and actuators, and they must respond in time commensurate with the activities of the system in its environment. One of the main challenges is that safety assurance, currently relying upon authority transfer from an autonomous function to a human to mitigate safety concerns, will need to address their mitigation by automation in a collaborative dynamic context. These challenges have a fundamental, multidimensional impact on the safety assurance methods, system architecture, and V&V capabilities to be employed. The goal of this report is to identify relevant issues to be addressed in these areas, the potential gaps in the current safety assurance techniques, and critical questions that would need to be answered to assure safety of IA systems. We focus on a scenario of reduced crew operation when an IA system is employed which reduces, changes or eliminates a human's role in transition from two-pilot operations.

Alves, Erin E.↗
NASA NTRS2018

Impairment of Human Ocular Tracking with Low-Dose Alcohol

Previous studies have documented adverse effects of alcohol on oculomotor performance. For example, moderate-dose alcohol (yielding a Blood Alcohol Concentration or BAC of 0.04-0.1%) has been shown to decrease steady-state pursuit gain (Fransson et al., 2010, Clin Neurophysiol, 121(12): 2134; Moser et al., 1998, J Neurol, 245(8): 542; Roche & King, 2010, Psychopharmacology, 212(1): 33), to increase saccade latency (Moser et al., 1998, J Neurol, 245(8): 542; Roche & King, 2010, Psychopharmacology, 212(1): 33), to decrease peak saccadic velocity (Fransson et al., 2010, Clin Neurophysiol, 121(12): 2134; Roche & King, 2010, Psychopharmacology, 212(1): 33), and to increase the frequency of catch-up saccades (Moser et al., 1998, J Neurol, 245(8): 542). Here, we administered two doses of ethanol on different days, yielding moderate (0.06%) and low (0.02%) levels of initial BAC, to examine the effects on human ocular tracking over BACs ranging from 0.00 to 0.07%. Twelve subjects (8 females) participated in a 5-day study. Three days of at-home measurements of daily activity and sleep were monitored, followed by two laboratory days where, ~5 hours after awakening, we administered one of the two possible single doses of alcohol. Using a previously published paradigm (Liston & Stone, 2014, J Vis, 14(14): 12), we measured oculomotor performance multiple times throughout the day with three pre-dosing baseline runs and bi-hourly post-dosing test runs until the subject recorded a BAC of 0.00% for two hours. BAC was measured before each run using an Alco-Sensor IV breathalyzer (Intoximeters, Inc., St. Louis, MO). For each of the oculometric measures, for each subject, we computed the within-subject % deviation for each test run from their baseline averaged across their three pre-dosing runs. We then averaged the data across subjects in 0.01% BAC bins. Finally, we used linear regression to compute the slope and x-intercept (threshold) of the mean binned % deviation as a function of BAC. We found that pursuit initiation was impaired at very low BAC levels, with significant (p < 0.002) linear trends in latency (+1.3%/0.01%BAC) and initial acceleration (-4.6%/0.01%BAC) with extrapolated absolute thresholds at or below 0.01% BAC. We also found that steady-state tracking was impaired showing significant (p < 0.002) linear trends in gain (- 3.8%/0.01%BAC) and catch-up saccade amplitude (+9.1%/0.01%BAC), again with extrapolated absolute thresholds around 0.01% BAC. We also found a significant (p < 0.02) increase in pursuit direction noise (+9.8%/0.01%BAC) with an extrapolated absolute threshold below 0.01% BAC. Many aspects of ocular tracking are impaired in a dose-dependent manner beginning at a BAC level around 0.01%, with significant effects at levels lower than previously reported and up to 8-times lower than the legal limit for driving in most states.

human performance↗
NASA NTRS2018

Aircraft Exceedances Vary According to Time of Day and Workload

The Flight Operational Quality Assurance (FOQA) programs have been implemented in US and Europe to identify anomalous flights based on data recorded on board an aircraft in an effort to improve flight safety. Numerous methods have been developed to support the analysis of FOQA data. However, it is unclear how FOQA data relates to the performance of the pilot. We sought to characterize the frequency and type of flight exceedances extracted from FOQA data during a controlled pilot schedule in order to determine whether patterns of exceedances related to human control of the aircraft would change according to scheduling factors.

flight data↗
NASA NTRS2018

Mobile Device Application for Monitoring Cyanobacteria Harmful Algal Blooms Using Sentinel-3 Satellite Ocean and Land Colour Instruments

Cyanobacterial harmful algal blooms (cyanoHAB) cause human and ecological health problems in lakes worldwide. The timely distribution of satellite-derived cyanoHAB data is necessary for adaptive water quality management and for targeted deployment of water quality monitoring resources. Software platforms that permit timely, useful, and cost-effective delivery of information from satellites are required to help managers respond to cyanoHABs. The Cyanobacteria Assessment Network (CyAN) mobile device application (app) uses data from the European Space Agency Copernicus Sentinel-3 satellite Ocean and Land Colour Instrument (OLCI) in near real-time to make initial water quality assessments and quickly alert managers to potential problems and emerging threats related to cyanobacteria. App functionality and satellite data were validated with 25 state health advisories issued in 2017. The CyAN app provides water quality managers with a user-friendly platform that reduces the complexities associated with accessing satellite data to allow fast, efficient, initial assessments across lakes.

Harmful Algal Bloom↗
NASA NTRS2018

Establishing and Monitoring an Aseptic Workspace

When are aseptic operations necessary? In order to meet certain bioburden requirements, some components must undergo dry heat microbial reduction (DHMR) or other sterilizing procedures. If sensitive surfaces must be re-exposed after DHMR, this could compromise the bioburden levels. Recontaminating sterilized surfaces could be costly both in time by requiring repeated DHMR and risk to the hardware, which may not be compatible with repeated high temperature bakes. In order to prevent recontamination of the sensitive surfaces, an aseptic environment and sterile technique must be employed. Aseptic environments mean working in a space with almost no detectable bioburden in the air or on surfaces. Ideally, DHMR happens as late as possible to avoid requiring aseptic operations, as it can be considered a high-risk operations. Preparing the cleanroom for aseptic operations Establishing an ISO (International Organization for Standardization) class 5 space to minimize airborne particles. Maintain low bioburden in the cleanroom by using biocidal cleaners. Using multiple biocidal techniques decreases the likelihood of selecting for resistant microorganisms. 70% Isopropyl Alcohol (IPA) denatures the proteins in a microorganism (note: 70% IPA is better at killing microorganisms than 100% IPA) 7% hydrogen peroxide: damages DNA and proteins through oxygen radical damage. Ultraviolet-C (UV-C) lamps: causes crosslinking in DNA which prevents replication. Monitor cleanroom regularly for bioburden trending: Standard bioassay: Swab or wipe samples of cleanroom surfaces processed for colony forming unity (viable or spore selected); Rapid bioassay: Adenosine triphosphate (ATP) or Limulus amebocyte lysate (LAL) for a bioburden snapshot. High levels can signal an immediate re-cleaning before standard bioassay samples are taken. Airborne monitoring: Active (pulling air through a filter) or passive (particle fallout) for bioburden. Verify bioburden levels just before aseptic operation. Test hardware and cleanroom surfaces and air 3 days before the planned aseptic operation. Rapid bioburden just before aseptic operation to ensure room was not re-contaminated. Preparing personnel and tools: Personnel training. Everyone in the cleanroom: Standard cleanroom certification Everyone on the team: 1 day Planetary Protection overview. Aseptic operators only: Half-day aseptic operations training. Covers sterile garmenting/gloves, Sterile handling with a focus on contact transfer risk, tool/GSE preparation, and two-operator system for opening sterilized tools/components. Tool sterilization: All tools to be used during an aseptic operation need to be identified. Compatible tools are sterilized by DHMR or Autoclave. Double wrapped so that the exterior bag can be handled by a non-sterile operator, and the sterile. Tools that are not compatible with high heat do not come in contact with sensitive surfaces: either substitutes are found, or tools are isolated by wrapping in sterile foil. During an aseptic operation. Pre-task to make sure everyone understands the operations, who is handling what, and when the most critical surfaces will be exposed. Monitoring during the operation. Bioburden: active and passive airborne bioburden sampling, glove-tip dabs onto a plate after completion of operation (3 days for results). Particles: real time particle counter constantly running, with alarm for exceeding ISO 5 conditions.

aseptic processing↗
NASA NTRS2018

Increased Dependence on Saccades for Ocular Tracking with Low Dose Alcohol

Previous studies have shown that certain features of oculomotor performance are impaired at or slightly below the legal limit for driving in most U.S. States (0.08% Blood Alcohol Concentration or BAC). Specifically, alcohol impairs saccadic velocity and steady-state tracking at levels between 0.04% and 0.1% BAC. Here we used a suite of standardized oculometric measures to examine the effect of ultra-low levels of alcohol (down to 0.01% BAC) on steady-state tracking. Our high-uncertainty tracking task reveals that the smooth pursuit system is highly sensitive to BAC, with impairmentextrapolating back to BAC levels at or below 0.01%. BAC generates a dose dependent increase in reliance on the saccadic system that maintains overall steady-state tracking effectiveness at least up to 0.08% BAC, albeit with a significant decrease in smoothness.

Tyson, Terence L.↗
NASA NTRS2018

Assimilating GCOM-W AMSR2 Radiance Data in Future GEOS Reanalysis

Surface and atmospheric radiation are being measured by space-borne conical scanning microwave radiometers with high accuracy and spatial resolution since 1980s'. These radiometers include Special Sensor Microwave Imager (SSM/I) onboard various NOAA's polar-orbiting satellites, Special Sensor Microwave Imager Sounder (SSMIS) onboard Defense Meteorological Satellite Program (DMSP) satellites, and Advanced Microwave Scanning Radiometer for EOS (AMSR-E), Advanced Microwave Scanning Radiometer 2 (AMSR2), Tropical Rainfall Measurement Mission (TRMM) Microwave Imager (TMI), and Global Precipitation Measurement (GPM) Microwave Imager (GMI) onboard NASA and JAXA's satellites. Atmospheric temperature, humidity, clouds, and precipitation are retrieved using brightness temperature data at frequencies between 22 GHz – 183 GHz. Some of the brightness temperature and retrieved rain rate data made by these imagers are assimilated in NASA Global Modelling and Assimilation Office (GMAO)'s weather and climate data sets including the Modern-Era Retrospective analysis for Research and Applications (MERRA) and its version 2 (MERRA-2) data sets. However, those radiance data are assimilated with the Goddard Earth Observing System model, version 5 (GEOS-5) only in clear-sky conditions. Recently, we started assimilate GPM/GMI radiance data with GEOS-5's atmospheric data assimilation system GSI under all-sky conditions in order to have better constraints in analyzed hydrological properties. GMAO plans to assimilate more microwave radiometers' brightness temperature data in its analyses. In this talk, we will discuss TMI and AMSR2 data's impact in temperature, humidity, clouds and precipitation under all-sky conditions in future GEOS reanalysis.

Jin, Jianjun↗
NASA NTRS2016

Spectral Monitoring of Volatiles During Drilling into Frozen Lunar Simulant

NASA's Resource Prospector (RP) project intends to characterize the 3D distribution of volatiles in permanently shadowed regions at the lunar poles. One RP remote sensing instrument is a near-infrared spectrometer with an associated camera and radiometer, called the Near-InfraRed Volatile Spectrometer System (NIRVSS). In May 2016, NIRVSS, a Honeybee Robotics drill, and an Inficon mass spectrometer were placed in a vacuum chamber at Glenn Research Center. Also inside was a tube (1.2 m high x 25 cm diameter) filled with lunar simulant NU-LHT-3M, initially doped with a homogeneous water abundance of ~5%, chilled to cryogenic temperatures and exposed to a vacuum (~10e-6 Torr). During drilling, the NIRVSS instruments observed the cuttings pile as subsurface materials were emplaced on the surface. Spectral features associated with water ice, near 2000 and 3000 nm, were measured by the spectrometer during drilling. The spectral data documents development of a desiccated soil layer in the tube down to ~25-30 cm (confirmed by post-test soil analyses), formed during the initial pump down to vacuum. Drilling occurred in 10 cm segments, with the drill stem extracted and flutes brushed after each 10 cm depth. One exception to this was the 40 cm depth segment where the soil was delivered to a sample capture mechanism, and sealed for post-test analyses. To ~30 cm depth the greatest 2000 and 3000 nm signatures were associated with brushing of the drill flutes above the surface. At depths >40 cm the strongest ice signatures were associated with the drill clearing soil from the existing hole, or beginning to encounter new material. For these greater depths, brushing the flutes after extraction produced much weaker ice signatures than for shallower depths. This suggests that the soil may remain trapped in the exit funnel and is not emplaced on the surface. After each event creating strong ice signatures, these signatures decreased to near background levels in 5 minutes or less, due to surface exposure to vacuum.

lunar poles↗
NASA NTRS2018

Thermal Modeling of Zero Boil Off Tank Experiment

Understanding fluid behavior in microgravity environments is essential to further development of cryogenic storage in space environments. The Zero Boil Off Tank (ZBOT) experiment was designed to investigate two-phase pressurization and depressurization of a tank in a microgravity environment. The test fluid was the refrigerant Perfluoro-normal-Pentane (PNP). Thermal modeling for the ZBOT model was conducted using Thermal Desktop and SINDA/FLUINT. The temperature distribution within the fluid of the tank is of particular interest. This particular work is centered on ascertaining the thermal behavior of the refrigerant in order to build more complete models of fluid in microgravity. Separate cases were run modeling experiments that were conducted both on the ground and on the International Space Station (ISS) to compare 1g and microgravity environments. The microgravity modeling cases consisted of a fluid lump representing the vapor ullage suspended in a solid to represent the liquid. Mass flow between the liquid and vapor was modeled using the Schrage equation for mass flow. Initial results indicate that the pressure rise and temperature increase within the fluid closely align with the experimental data by matching initial conditions of the experiment. This work is ongoing and will yield further insights into the thermal behavior of fluid mixing in microgravity.

low-gravity fluid modeling↗
NASA NTRS2013

Capabilities, Performance, and Status of the SOFIA Science Instrument Suite

The Stratospheric Observatory for Infrared Astronomy (SOFIA) is an airborne observatory, carrying a 2.5 m telescope onboard a heavily modified Boeing 747SP aircraft. SOFIA is optimized for operation at infrared wavelengths, much of which is obscured for ground-based observatories by atmospheric water vapor. The SOFIA science instrument complement consists of seven instruments: FORCAST (Faint Object InfraRed CAmera for the SOFIA Telescope), GREAT (German Receiver for Astronomy at Terahertz Frequencies), HIPO (High-speed Imaging Photometer for Occultations), FLITECAM (First Light Infrared Test Experiment CAMera), FIFI-LS (Far-Infrared Field-Imaging Line Spectrometer), EXES (Echelon-Cross-Echelle Spectrograph), and HAWC (High-resolution Airborne Wideband Camera). FORCAST is a 540 m imager with grism spectroscopy, developed at Cornell University. GREAT is a heterodyne spectrometer providing high-resolution spectroscopy in several bands from 60240 m, developed at the Max Planck Institute for Radio Astronomy. HIPO is a 0.31.1 m imager, developed at Lowell Observatory. FLITECAM is a 15 m wide-field imager with grism spectroscopy, developed at UCLA. FIFI-LS is a 42210 m integral field imaging grating spectrometer, developed at the University of Stuttgart. EXES is a 528 m high-resolution spectrograph, developed at UC Davis and NASA ARC. HAWC is a 50240 m imager, developed at the University of Chicago, and undergoing an upgrade at JPL to add polarimetry capability and substantially larger GSFC detectors. We describe the capabilities, performance, and status of each instrument, highlighting science results obtained using FORCAST, GREAT, and HIPO during SOFIA Early Science observations conducted in 2011.

SOFIA↗
NASA NTRS2019

Uncertainty Analysis of the CE-22 Advanced Nozzle Test Facility

This paper presents methods and results of a detailed measurement uncertainty analysis that was performed for the Advanced Nozzle Test Facility, CE-22, located at the NASA Glenn Research Center. Results for the uncertainty in thrust and flow coefficients, in addition to other variables of interest, are provided. Results are presented separately as random uncertainty (characterizing errors inherent to instrument or measurement environment, impacting repeatability), systematic uncertainty (capturing inaccuracies due to measurement process, calibration, installation effects or other sources which may introduce bias), and total combined uncertainty. The statistical methods and engineering judgments used to estimate elemental uncertainties are described. The analysis tool MANTUS (Measurement Analysis Tool for Uncertainty in Systems) was used to quantify instrumentation system uncertainty, and statistical analysis and engineering judgment were used to quantify other random and systematic uncertainty sources. The Monte Carlo method was used to propagate systematic and random elemental uncertainties to determine the uncertainties of various calculated variables of interest.

data quality↗
NASA NTRS2014

Variation in Sleep Duration and Circadian Phase by Duty Start Time Among Short-Haul Commercial Airline Pilots

Prior studies have confirmed that commercial airline pilots experience circadian phase shifts and short sleep duration following travel with layovers in different time zones. Few studies have examined the impact of early and late starts on the sleep and circadian phase of airline pilots who return to their domicile after each duty period. We recruited 44 pilots (4 female) from a short-haul commercial airline to participate in a study examining sleep and circadian phase over four duty schedules (baseline, early starts, mid-day starts, late starts). Each duty schedule was five days long, separated by three rest days. Participants completed the rosters in the same order. Sleep outcomes were estimated using wrist-borne actigraphy (Actiware Software, Respironics, Bend, OR) and daily sleep diaries. Thirteen participants volunteered to collect urine samples for the assessment of 6-sulfatoxymelatonin (aMT6s). Urine samples were collected in four hourly bins during the day and eight-hourly bins during sleep episodes, for 24 hours immediately following each experimental duty schedule. The aMT6s results were fit to a cosine in order to obtain the acrophase to estimate circadian phase. Univariate statistics were calculated for acrophase changes, schedule start times and sleep times. All statistical analyses were computed using SAS software (Cary, IN).The mean duty start times varied as expected (baseline 10:17 [ 3:50], early starts 5:24 [ 0:30], mid-day starts 13:52 [ 1:20], late starts 16:33 [ 1:33]). Actigraphy-derived sleep duration varied between schedule types, with the shortest average sleep durations occurring during the early starts and night duty. Mean circadian phase was similar during each schedule type (baseline 26:14 [ 3:22], early starts 25:29 [2:13], mid-day starts 26:20 [ 3:16], late starts 25:49 [ 4:28]), but there were wide inter-individual differences in phase shifting from the beginning to the end of the study, with phase shifts ranging from a 5.98 hour phase advance to an 11.34 hour phase delay. Our preliminary findings suggest that early and late starts are associated with reduced sleep duration. The dispersion in inter-individual differences in circadian phase across shifting duty schedules should be further evaluated to determine how schedule-induced phase shifts may affect operational performance.

Flynn-Evans, Erin↗