Naval Aviation Research Articles

Synergistic impact of corrosion pitting on the rotating bending fatigue of additively manufactured 316L stainless steel: Integrated experimental and modeling analyses

In this study, the ex-situ rotating bending corrosion fatigue behavior of laser powder bed fused stainless steel (SS) 316L has been studied incorporating experimental analyses and modeling. The findings revealed significant variations (almost 20 %) in fatigue lifetime in pre-corroded specimens relative to non-corroded (virgin) specimens because of corrosion-derived pitting phenomena on the surface. To this end, the fatigue strength of virgin (non-corroded) and pre-corroded SS 316L were recorded at 242 MPa and 203 MPa, respectively. Upon conducting the fatigue tests and extracting stress-life trends, advanced microstructural characterization and postmortem analyses were used to quantify fatigue crack behavior and fracture surface. An empirical model is also developed employing depth-sensing indentation testing, linear elastic fracture mechanics, and computer tomography scans to propose an optimum predictive trend. The analysis comparing existing models with our proposed model demonstrates reasonable agreement between experimental findings and the predicted life for the studied laser powder bed fused SS 316L material exposed to corrosion rotating bending fatigue test. The findings of this research carry important contributions to the structural integrity and longevity of marine engineering, ship construction, naval operations, and naval aviation where materials and components are exposed to cyclic loading and corrosion.

Automatic Ground-Truth Image Labeling for Deep Neural Network Training and Evaluation Using Industrial Robotics and Motion Capture

Abstract The United States Navy (USN) intends to increase the amount of uncrewed aircraft in a carrier air wing. To support this increase, carrier-based uncrewed aircraft will be required to have some level of autonomy as there will be situations where a human cannot be in/on the loop. However, there is no existing and approved method to certify autonomy within Naval Aviation. In support of generating certification evidence for autonomy, the United States Naval Academy (USNA) has created a training and evaluation system (TES) to provide quantifiable metrics for feedback performance in autonomous systems. The preliminary use case for this work focuses on autonomous aerial refueling. Prior demonstrations of autonomous aerial refueling have leveraged a deep neural network (DNN) for processing visual feedback to approximate the relative position of an aerial refueling drogue. The training and evaluation system proposed in this work simulates the relative motion between the aerial refueling drogue and feedback camera system using industrial robotics. Ground-truth measurements of the pose between the camera and drogue are measured using a commercial motion capture system. Preliminary results demonstrate calibration methods providing ground-truth measurements with millimeter precision. Leveraging this calibration, the proposed system is capable of providing large-scale datasets for DNN training and evaluation against a precise ground truth.

Photorefractive Keratectomy in Student Naval Aviators: Outcomes of the U.S. Navy Accessioning Study.

To present the outcomes of the U.S. Navy photorefractive keratectomy (PRK) accessioning study conducted between 2000 and 2005 that helped lead to the acceptance of laser vision correction within the U.S. aviation industry. In this prospective masked study, a total of 301 students who had PRK and underwent naval flight training were compared to 4,368 untreated peers. Three training pipelines were compared: propeller/jet transport, jet fighters, and helicopters. The evaluated metrics were flight and academic performance (assessed for the primary and advanced stage of the training as normalized Navy Standard Score [NSS]), as well as the student attrition rate from training. The attrition rate was lower in the PRK group compared to controls (15.9% vs 23.2%; P = .004). In the primary stage of training, students who had PRK outperformed controls in flight training performance in the propeller/jet transport pipeline (average NSS after PRK: 52.4 ± 7.5 vs controls: 50.7 ± 6.4, P = .02), but the flight performance in the jet fighter and helicopter pipelines was comparable between the two groups. Academic performance in the primary stage of training was approximately 7% to 13% higher in students who had PRK for all training pipelines. During the advanced training stage, there was no difference in the flight performance between the groups in any of the presented pipelines. Academic performance was significantly better for students who had PRK in the helicopter pipeline (51.2 ± 11.0 vs 46.7 ± 11.7 P < .001) but comparable between the two groups in the remaining pipelines. Refractive surgery did not have adverse effects on flight performance metrics. Pilots who had PRK had comparable or better outcomes than their untreated peers. [J Refract Surg. 2024:40(3):e173-e181.].

Professor Alexey Nikolaevich Kuchmin (on the 60th anniversary of his birth)

On July 27, 2023, Alexey Nikolaevich Kuchmin, the Head of the Department of Propaedeutics of Internal Diseases of the Military Medical Academy, named after S. M. Kirov&#x0D; doctor of Medical Sciences, Professor, and former chief therapist of the Ministry of Defense of the Russian Federation, turned 60 years old. A. N. Kuchmin was born on July 27, 1963, in Mineralnye Vody, Stavropol Territory. After graduation, he entered the Faculty of training doctors for the Navy of the Military Medical Academy named after S. M. Kirov, where he graduated with honors in 1986. For 4 years, he served as the Head of the medical center and the infirmary of the Baltic Fleet Naval Aviation. Since 1990, his life and fate have been inextricably linked with the Department of Propaedeutics of Internal Diseases of the Kirov Military Medical Academy, within the walls of which he has passed through a difficult but bright career path from a 3rd-year cadet to an associate Professor, from a teacher to a Professor and Head of the Department. Here, A. N. Kuchmin joined the scientific, pedagogical, and clinical ideas of Professor N. N. Savitsky. Having started his scientific activity under the guidance of Professor Yu. S. Malov, Alexey Nikolaevich devoted himself to the research of the most pressing issues of cardiology, pulmonology, and physiology. After graduating from the adjunct program in 1993 at the Department of Propaedeutics of Internal Diseases of the Academy, A. N. Kuchmin defended his PhD thesis on “The role of salivary glands in maintaining homeostasis in patients with hypertension”. Since that time, he has been a senior resident, then a teacher, associate Professor, and deputy Head of the Department of Propaedeutics of Internal Diseases (for clinical work) since 2005. In 2003, Alexey Nikolaevich defended his doctoral dissertation on cardiac arrhythmias in patients with bronchial asthma. His research interests now include issues in rapidly developing areas, such as endocrinology, ultrasound diagnostics, and functional diagnostics. During his work as the Chief therapist of the Ministry of Defense of the Russian Federation, A. N. Kuchmin proved himself to be a competent Head of the therapeutic service of the Ministry of Defense of the Russian Federation, particularly during the armed conflict in Abkhazia and Georgia. A. N. Kuchmin’s talent as a clinician and organizer of clinical and expert work was also manifested in his leadership from November 2008 to 2010 in the Department of Therapy of the State Institute of Advanced Training of Doctors of the Ministry of Defense of the Russian Federation and since 2015 in his native Department of Propaedeutics of Internal Diseases of the Military Medical Academy named after S. M. Kirov. In all his positions, Alexey Nikolaevich was and remains a highly professional specialist in his field with several clinical interests and knowledge.

The need for specificity in uncertainty communication is further supported: Preliminary evidence from eye tracking

Automation transparency is understudied in environments with varied automation reliability. We previously found uncertainty communication, a form of automation transparency, led to nuanced and unintentional performance outcomes in this type of environment. To better understand these outcomes, participants’ monitoring policies of automation were studied via a preliminary eye tracking analysis. In a simulated multi-UAV mission, 272 Naval Aviation trainees monitored three automated systems that were identical in function, but differed in reliability. Halfway through the experiment, uncertainty communication about the least reliable system was delivered as a chat message. Performance improvements coincided with a monitoring policy that had larger dwell times overall and one where the proportion of visual attention towards the automated system mentioned in the uncertainty communication increased upon its delivery. Overall, examining participant monitoring policies helped explain other performance outcomes and bolstered our previous conclusion: effective uncertainty communication requires maximum specificity.

Коротковолновый успех арктической экспедиции Дональда Макмиллана

It shows how naval aviator Richard Baird, explorer Donald MacMillan and Zenith Radio solid Eugene MacDonald successfully realized the first Arctic expedition using power and shortwave radio. The focus is on Zenith Radio Corp. shortwave radio technologies that deliver a specific goal and achieve success.

Bioinspired Aerodynamic Load Estimation for UCAVs in Turbulent Environments

Small aircraft carriers play a crucial role in military navigation and field intelligence. Unmanned Combat Aerial Vehicles (UCAVs) have emerged as indispensable tools for various military operations. However, the efficacy of UCAV operations is often hampered by the turbulent conditions generated by oceanic gusts. To enhance the reliability and autonomy of these systems, this research focuses on advancing aerodynamic load estimation techniques.&#x0D; Many biological systems employ sensory systems to collect environmental feedback to improve predation and avoid attack. Examples include the proprioception exhibited in bird feathers and the lateral line function in fish. Drawing inspiration from these biological models, a system of sensors is employed to achieve more precise estimations of the UCAV aerodynamic state and therefore train an existing Multi-Layer Perception Artificial Neural Network (MLP ANN) to respond to the environment.&#x0D; A series of experiments were conducted on a non-slender delta-wing model of NACA 0012 mounted on a force/moment sensor and exposed to varying flow conditions in a controlled setup called the WindShaper. To simulate gusty environments, the WindShaper produced unsteady random axial gusts ranging from 5m/s to 15m/s. A total of 100 sets of data, consisting of 60000 data points were collected and used to train the MLP ANN.&#x0D; Statistical methods were employed to distinguish valid and edge cases within the datasets. From analyzing the outputs generated by the MLP ANN, it was determined that there exists an importance in collecting data of high quality. These analyses identify factors affecting model performance and highlight specific challenges that hinder accurate gust prediction. The utilization of advanced neural network methodologies as a technique for load estimation has significant implications for naval aviation, aerodynamics, and their related autonomous systems. This research contributes to the development of more robust UCAV operations in challenging environments.

Henri-Pierre Grolleau, French Naval Aviation by Chris Madsen

Henri-Pierre Grolleau, French Naval Aviation by Chris Madsen

A Framework for Airworthiness Certification of Autonomous Systems Within United States Naval Aviation

A need has been identified to establish a strategy and framework for airworthiness certification of autonomous systems in Naval Aviation. The purpose of this research was to document a two-day virtual summit that was held in June 2021 to develop an initial strategy and framework for airworthiness certification of autonomous functionality in Naval Aviation air systems. The summit was designed to engage the airworthiness community to start the development of a strategy and framework for airworthiness certification of autonomous systems. The summit was attended by representatives from government, industry and academia. Following two full days of discussions, the group came to a consensus on a strategy and framework for airworthiness certification of airborne autonomous functions based on an example use case: an unmanned aircraft performing a drogue aerial refueling task. This paper summarizes the summit and it’s outcomes in an effort to stimulate the certification community to develop methods for certifying autonomous behaviour.

Stretching and Self-Myofascial Release in Helicopter Aircrew to Reduce Neck and Back Pain (Phase 1).

This prospective intervention study was designed to determine the efficacy of a standardized Preflight/Postflight Stretches (PPS) protocol to reduce subjective neck and back pain scores in helicopter aircrew. Aircrew transient back and neck pain is well documented, and there is currently no standardized preflight and postflight stretching protocol for Naval Aviation. Subjects were recruited from two carrier air wing MH-60R squadrons at Naval Air Station Jacksonville. These carrier air wing squadrons were selected to control for size (number of aircrew), age, and operational tempo (number of flight hours). Subjects consisted of both pilots and enlisted aircrew. One squadron was designated as the control group, although the second squadron served as the intervention group. Subjects from both groups filled out the questionnaire. Only the intervention group completed the PPS protocol immediately after completing the questionnaire and before departing the squadron spaces for the aircraft outside. Upon landing, the aircrew completed a postflight debrief. Only the intervention group completed the PPS protocol after debrief. Both the intervention and control groups once again completed the questionnaire. Questionnaires were matched by using a generated anonymous subject ID. The amounts of change and pain levels were then compared using the Mann-Whitney test and the Fisher's exact test, respectively. The Kolmogorov-Smirnov test found the data to be nonparametric. The preflight and postflight overall (P ≤ .001), cervical (P ≤ .001), thoracic (P = .006), and lumbar (P = .004) differences between the control and intervention groups were found to be statistically significant when using the Mann-Whitney test. Preflight and postflight pain differences in the sacral region and "other" section were not found to be statistically significant (sacral, P = .618; others, P = .182). When evaluating the worsening of the pain level, 50 (92%) of the control flights in which PPS was not performed reported worse pain, compared to 21 (61.8%) in the intervention group where PPS was performed. The Fisher's exact test found the association between performing PPS and the worsening in pain to be statistically significant (P = .001) in the overall, cervical, thoracic, and lumbar regions. Therefore, the hypothesis was accepted in regard to overall pain, as well as in the cervical, thoracic, and lumbar regions. Aircrew back and neck pain because of flying is well documented. However, there is no standardized stretching protocol for aircrew to perform immediately preflight or postflight in U.S. Naval Aviation. This study demonstrated that PPS, a simple 5- to 7-min stretching routine, gives aircrew structure and can reduce postflight cervical, thoracic, lumbar, and overall pain. This phase proved to be safe as no adverse events were reported. The prehabilitation aspect could reduce conventional medical intervention, costly pharmacological management of neck and back pain, and be applied to other aviation populations in military and civilian communities.

Specificity of the professional activity of naval aviation helicopter pilots

An important component of the military-professional training of cadets-military pilots in military aviation universities is the formation of readiness for practical activities in the troops. At the same time, the quality of training of aviation specialists does not fully meet the requirements of customers for military personnel. It is possible that the reason for this discrepancy lies in the insufficiently expressed methodological strategy of military professional training. Modern military-political conditions and trends in the development of naval aviation require that helicopter pilots have personality neoplasms that contribute to the high-quality performance of professional tasks in all types of activities. The conducted genesis of the military professional training of helicopter pilots of naval aviation revealed a number of significant problems, the solution of which is facilitated by methodological approaches of professional pedagogy. In the course of the study, based on the activity approach and the principle of identification, the leading role of interaction in all types of professional activity was established, which determines its specificity. Content- analysis of professional tasks based on a functional approach revealed a feature of professional activity, which consists in a set of professional tasks corresponding to indicators in the structure of readiness for interaction. On the basis of a system-structural approach, taking into account the specifics and features of activity, the structure of readiness for interaction (motivational-value, activity and cognitive components) and the criteria for the formation of its components (crew flight, military cohesion and tactical flight thinking) are proposed. Arguments are given regarding the need to develop readiness for interaction among helicopter pilots of naval aviation during their training at a military aviation university, as an integrative personality trait, which includes not only a set of abilities to solve professional problems, but also a number of professionally important qualities

Using a run time assurance approach for certifying autonomy within naval aviation

AbstractThe methods and procedures within United States naval aviation to certify an aircraft safe for flight are well established. However, these methods and procedures are based on clearing a system that is operated or monitored by a human. A fully autonomous system will not have a human in or on the loop and will therefore require a new method for certifying it safe for flight. This paper details how to use run time assurance as the framework for a safety of flight certification of autonomous behavior within United States naval aviation. We present an aerial refueling task with run time assurance as use case for the framework for certification. Within the use case we then give more details on the mechanics of using RTA to enable autonomous functionality within naval aviation.

Evaluating the Challenges and Potential Complications of Breastfeeding in Naval Aviation.

Active duty flight crew plays a critical role in military operations. The occupational demands of the flying environment require a certain level of medical suitability. Additionally, such an environment could be more hazardous for certain populations. While the Centers for Disease Control and Prevention, the American Academy of Pediatrics, and the World Health Organization strongly support exclusive breastfeeding for the health benefit of both the mother and the child in the first 6 months of life, the aeromedical implications of lactating are not widely discussed. Breastfeeding is inherently challenging for many women, in part because of the frequent emptying required to maintain breastmilk supply and avoid complications such as engorgement, clogged ducts, and mastitis. This pilot study evaluated the experiences of individuals concurrently breastfeeding while on active duty Naval flying status to (1) assess whether these individuals experience frequent challenges or complications associated with lactating and (2) establish the need for future expanded studies. This survey-based, retrospective, descriptive study evaluated the experiences of 17 lactating individuals on active duty Naval flying status. Women were recruited using word of mouth and social media platforms. Responses were tabulated and summarized from the survey, which included yes/no questions and free-response sections regarding flying position, breastfeeding history, and breastfeeding challenges. This trial was approved by the Naval Air Warfare Center Aircraft Division (NAWCAD) Institutional Review Board (Protocol Number NAWCAD.2021.0004-IR-EP7). Of the 27 women who received study materials after expression of interest, 17 individuals completed the informed consent and survey protocols. Although limited by sample size and the demographics of respondents, the results highlight that the active duty flying environment did impact the breastfeeding experiences of the participants, with 88% of respondents reporting some difficulty or complication associated with breastfeeding and the operational flying environment. Difficulty in maintaining breastmilk supply, engorgement, and the need for supplementation were some of the concerns discussed. This study hypothesizes that occupational demands associated with aviation result in a decreased ability to maintain exclusive breastfeeding, an increased risk for engorgement and clogged ducts, and a higher likelihood of early weaning among Naval aviators. It included only the perspectives of Naval officers, thereby lacking the input of enlisted aircrew on flight status, who comprise a large population of active duty flyers. The responses, although limited by a lack of controls and survey limitations, indicate that a future study to expand understanding of the aeromedical implications on lactating individuals would be valuable for improving workplace support and the ultimate success of lactating women in meeting their breastfeeding goals.

American peacetime naval aviation and the Battle of Midway

Abstract There are many explanations for the victory of the United States against the Japanese at the Battle of Midway on June 4, 1942. Mistakes made by the Japanese certainly factored in the outcome and the United States also had certain advantages. However, an important if not sufficient explanation for the US victory is the pre-war preparation of the US Navy during peacetime. Designed by Ed Heinemann at Douglas Aircraft in El Segundo, California, from 1934 until 1938, the first Dauntless planes were delivered to the navy in 1940, well in advance of the Japanese attack on Pearl Harbor, the moment which is conventionally regarded as the US entry into the war. The pilots of the Dauntless, as I will show in this essay, were much the same; they too were the product of a peacetime Navy.

Book Review: The Development of British Naval Aviation, 1914-1918 by Alexander Howlett

Book Review: <i>The Development of British Naval Aviation, 1914-1918</i> by Alexander Howlett

Eject, Eject, Eject! Conducting a Cognitive Task Analysis to Assess Parachute Descent Training Simulators

We conducted a cognitive task analysis to provide input on the curriculum and technology currently used to train parachute descent procedures in the Naval Aviation Survival Training Program. Subject matter experts provided insight into the correct decision-making thought processes used in parachute descent. Techniques for analysis included focus groups, interviews, and a think-aloud procedure involving a parachute descent simulator at a Naval Aviation Survival Training Center. Results and findings inform the instructional design process to improve the training pipeline’s development, implementation, and evaluation.

The effectiveness of uncertainty communication with varied automation reliability: Specificity is necessary but (potentially) not enough

Automation reliance and functionality are ever increasing, especially in supervisory control environments like unmanned aerial vehicle (UAV) missions. Of particular relevance is understanding how automation transparency, i.e., explaining the capabilities and limitations of automation to the human in real-time, can improve human-automation performance across automated systems that vary in reliability. Two hundred seventy one Naval Aviation trainees completed a simulated multi-UAV supervisory control mission for 42 minutes with three automated systems that varied in reliability. Participants were never explicitly told the reliability varied, but halfway through the mission, they were alerted that the least reliable system may falter. Results indicated human-automation performance improved after the alert for this specific system, but not as a whole, as one system’s human-automation performance deteriorated. This work suggests uncertainty communication should not only include the specific, real-time capabilities of the automation, but also communicate unintentional consequences it may have on the whole environment.

My Mind Was a Military Sky

My Mind Was a Military Sky

Conflicting spatial representations impairs object tracking performance in an aerospace environment

The purpose of this study is to extend the small number of applied research studies in Unmanned Aerial Systems (UAS) sensor control to a more ecologically valid human performance application set (i.e., airborne object tracking). In this study, United States Naval Aviators and Aircrew (N = 8) assumed the role of a sensor operator for a simulated unmanned aerial system while riding in an airborne Lockheed P-3 Orion aircraft. The P-3 flew in two flight conditions that differed in the level of intermittent ascending, descending, and turning profiles to induce two levels of spatial incongruity with the UAS sensor operator screen. Participants also performed trials on the ground to establish baseline performance measures. Results show that the incongruent visual and vestibular cues experienced by the participants during flight induced spatial incongruity and an overall decrease in operator tracking performance [F(2, 3872) = 14.04, p< 0.001)] compared to ground baseline trials. Exploratory findings suggest that motion sickness could be an important consideration for future in-flight UAS sensor control. Interestingly, results also indicate that performance decrements due to the flight environment alleviate to normal performance levels over time. Therefore, a training regime may suffice to ameliorate the effects of spatially discordant environments on human performance.

Austin Bradford Hill: simply the best

Austin Bradford Hill was born on July 8, 1897, third son of Sir Leonard Erskine Hill, a distinguished medical physiologist, Professor of Physiology at The London Hospital. He grew up in an upper class Victorian family. Sir Leonard, who created an ingenious instrument for blood pressure measuring, had a deep influence on his son. In fact, Bradford decided to follow his father example. He attended Chigwell Grammar School, which was established in 1629, but unfortunately, Bradford’s decision to join the Faculty of Medicine coincided with a really big event: First World War. Bradford entered British naval aviation and...