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Multitasking is increasingly common in highly complex and safety‐critical systems, especially under abnormal situations. Mental overload (MOL) may occur and result in forgetting/mistaking tasks uncertainly. Such probabilistic errors could have catastrophic consequences and contribute greatly to the multitasking risk of man‐machine systems. In this paper, to better identify the risks of safety‐critical multitasking situations, MOL mechanism is investigated and a risk analysis method considering MOL is proposed. MOL occurs when the demand for resources estimated by Multiple Resources Model exceeds an operator's ability. Then, the operator's performance degrades, and s/he tends to mistake or abandon parts of tasks. Based on the MOL mechanism, a MOL‐performance dependency (MOL‐PDEP) gate is proposed to incorporate MOL into risk analysis. Its inputs are concurrent tasks, and it triggers the related hazardous human behavior events with certain probabilities if MOL occurs. Through this gate, the dependence among these events and their nondeterministic cause relationships to MOL are added to traditional fault tree (FT), which presents a challenge issue to FT analysis. An implicit method is proposed to analyze the FT with MOL‐PDEP gate and calculate the accident probability. A case study on a helicopter crash accident demonstrates the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Loss of tail rotor effectiveness (LTE), also known as unanticipated yaw, has been recognized to be a major contributing factor in several helicopter accidents due to the loss of directional control. Flight tests have identified specific wind azimuth regions that may alter the angle and the speed of the airflow through the tail rotor leading to LTE. Through the helicopter flight data monitoring (HFDM) program, pilots receive constant flight evaluation reports to support LTE risk mitigation. Nevertheless, the existing LTE safety metric presents several pitfalls that hinder the reliability of the detection of violations of boundaries for flight safety. To identify the appropriate methods to properly simulate and flag LTE events and develop a more comprehensive and reliable LTE safety metric to be used within the HFDM environment, a physics-based investigation of the different LTE flight characteristics is performed. The results from this investigation are expected to contribute towards an improvement in detection of LTE events, leading to a reduction in LTE-related accidents. [ABSTRACT FROM AUTHOR]

High-resolution three-dimensional data from sensors such as LiDAR are sufficient to find power line towers and poles but do not reliably map relatively thin power lines. In addition, repeated detections of the same object can lead to confusion while data gaps ignore known obstacles. The slow or failed detection of low-salience vertical obstacles and associated wires is one of today's leading causes of fatal helicopter accidents. This article presents a method to efficiently correlate vertical structure observations with existing databases and infer the presence of power lines. The method uses a spatial hash key which compares an observed tower location to potential existing tower locations using nested hash tables. When an observed tower is in the vicinity of an existing entry, the method correlates or distinguishes objects based on height and position. When applied to Delaware's Digital Obstacle File, the average horizontal uncertainty decreased from 206 to 56 ft. The power line presence is inferred by automatically comparing the proportional spacing, height, and angle of tower sets based on the more accurate database. Over 87% of electrical transmission towers were correctly identified with no false negatives. [ABSTRACT FROM AUTHOR]

This article considers important potential legal consequences from the helicopter tragedy in January 2023 in which four people were killed. The event raises legal issues including the viability of potential claims for psychiatric injury for those who unwittingly observed the horrible events or who provided rescue efforts, acknowledging that, at this time, no fault has yet been established in any individual. As will be shown, the law in the United Kingdom (UK) has proceeded along a path with respect to these claims that has arguably become untenable and indefensible. The High Court of Australia has not considered claims for psychiatric claims for more than 20 years, presenting our Court with an opportunity, if one arose, to set our law on a different path than the UK example. [ABSTRACT FROM AUTHOR]

Aviation statistics identify collision with terrain and obstacles as a leading cause of helicopter accidents. Assisting helicopter pilots in detecting the presence of obstacles can greatly mitigate the risk of collisions. However, only a limited number of helicopters in operation have an installed helicopter terrain awareness and warning system (HTAWS), while the cost of active obstacle warning systems remains prohibitive for many civil operators. In this work, we apply machine learning to automate obstacle detection and classification in combination with commercially available airborne optical sensors. While numerous techniques for learning-based object detection have been published in the literature, many of them are data and computation intensive. Our approach seeks to balance the detection and classification accuracy of the method with the size of the training data required and the runtime. Specifically, our approach combines the invariant feature extraction ability of pretrained deep convolutional neural networks (CNNs) and the high-speed training and classification ability of a novel, proprietary frequency-domain support vector machine (SVM) method. We describe our experimental setup comprising the CNN+SVM model and datasets of predefined classes of obstacles--pylons, chimneys, antennas, TV towers, wind turbines, helicopters--synthesized from prerecorded airborne video sequences of low-altitude helicopter flight.We analyze the detection performance using average precision, average recall, and runtime performance metrics on representative test data. Finally, we present a simple architecture for real-time, onboard implementation and discuss the obstacle detection performance of recently concluded flight tests. [ABSTRACT FROM AUTHOR]

There is little empirical evidence on the predictive value of safety culture assessments (SCAs) in relation to how accident‐prone an organisation might be. Recently, Antonsen not just demonstrated how a quantitative SCA mispredicted future safety outcomes, but actually showed an inverse relationship between the assessment and subsequent critical incident investigation findings. To add to our understanding, this article presents research on whether a SCA has a predictive capacity for safety outcomes. Like in Antonsen's research, an opportunity emerged when a helicopter taxiing accident, resulting in a rotor strike occurred for a helicopter squadron that had just undergone a SCA. The assessment used 'culture ladder' rubrics for its findings, which allowed us to look for specific features in the subsequent independent accident investigation (in which the researchers were not involved). As with Antonsen's findings, our research shows that a 'ladder'‐based assessment has little predictive value. Any predictive value it has is in the inverse of the assessment findings. For instance, where the SCA showed that the safety culture was very mature regarding finding a balance between safety and the mission at hand or the breaking of rules, the accident investigation pointed these out as the causes of the accident. [ABSTRACT FROM AUTHOR]

The article is focused on the statistics of aviation accidents of military helicopters in the service of Czechoslovakia and the Czech Republic since 1956, when helicopters were first assigned to military units in the former Czechoslovakia, until the end of 2021. It contains not only a unique and previously unpublished comprehensive numerical overview of aviation accidents (disasters, crashes and damage events), but also an analytical review in terms of the type of accidents, the date of their occurrence, the type of helicopter and also the number of killed and surviving crew members. These numerical summaries are accompanied by comments, as well as by a list of literature and information sources that are currently still available in relation to the subject. [ABSTRACT FROM AUTHOR]

Technical failures in helicopters are a main concern for helicopter safety. The prominence of mechanical failures differs for specific helicopter operations. This analysis used 151 General Aviation accident reports from the National Transportation Safety Board online database from an 11-year time period. The information in each report was collated, including the list of findings for each accident. Possible relations between causes and specific flight operations were analyzed by looking at significant differences between expected and actual values within the dataset of categorical data. It is found that the proportion of fatal accidents in this category of accidents is low (16.6%) compared with the percentage of fatal helicopter accidents in general, as well as those of specific helicopter operations. Instructional flights appear significantly more likely to be associated with maintenance-related causes. Causes related to fatigue of aircraft parts are more often associated with ferry and positional flights, as well as helicopters with turbo-shaft engines. Future research is recommended for these specific associations to further mitigate the number of accidents with non-powerplant failures. [ABSTRACT FROM AUTHOR]

The article presents an analysis of air accidents involving military helicopters used in Czechoslovakia and the Czech Republic from their introduction in 1956 to the end of 2021. It focuses on the contribution of human factors of flight personnel to these air accidents. The aim of the article is, based on extensive analyses of the circumstances and causes of individual air accidents, to formulate the root causes of the factors that have threatened and still threaten the lives of not only pilots, but also other members of military helicopter flight crews while performing their profession. To conclude, recommendations are given to reduce, or in many cases even to eliminate, the effects of these factors on flight safety. [ABSTRACT FROM AUTHOR]

• Two incidences of failures of collective control rods of a particular type of helicopter were investigated. • In both the cases, the failure occurred at the threaded region of Al-alloy tube by fatigue mechanism. • Reasons for the two failures were different; manufacturing deficiency in one and assembly error in the other. This paper presents two incidences of failures of collective control rods which resulted in accidents to a particular type of helicopter. The control rods were made of 2024 Al-alloy tubes fitted with fork at one end and a spherical bearing at the other end (eye-end). In terms of physical appearance, the two failures in the control rods were identical to each other wherein there was fracture in the Al-alloy tube at the eye-end. Fractography study confirmed that in both the cases, multiple fatigue cracks had initiated over a sector at the internal thread roots on the Al-alloy tubes corresponding to 1st/2nd thread on the eye-end stud. After initiation, the cracks had propagated progressively into the tube-wall and then along the circumferential direction. As the crack propagation progressed, the load bearing capacity of the tubes diminished resulting in final overload fracture under the operational load at the time of accidents. Although failures in both the control rods looked alike in terms of failure location, fracture pattern and fracture mechanism, the primary reasons of failures were found to be different. Investigation revealed that premature fatigue crack initiation was due to non-uniform stress distribution on the internal threads of the control tube with increased level of stress over a sector. In one case, the non-uniform stress distribution resulted from thread manufacturing deficiency, and in the other case, it was due to incorrect assembly at the eye-end. [ABSTRACT FROM AUTHOR]

On January 26, 2020, former Los Angeles Lakers superstar Kobe Bryant passed away suddenly in a helicopter crash. Drawing on theoretical frameworks of racial and gender politics in the U.S. context, and media framing, we conducted a textual analysis of mainstream news media's framing of "Mamba Mentality" in the immediate aftermath of Bryant's death. Across the 119 articles retrieved for analysis, we found Mamba Mentality consistently framed in four ways: a performance standard, both mental and physical; a symbol for overcoming adversity; a commodity; and a legacy/ethos. While mainstream media was complicit in absolving Bryant of his 2003 sexual assault allegation, the allegation was folded into his complex celebrity identity, which ultimately legitimized his Mamba Mentality persona as strong, tough, and able to overcome any obstacle that stood in the way—regardless of the cost. Our findings implicate how a celebrity athlete's life is valued by contemporary media, and how media portrayals represent historical underpinnings of identity politics and oppressive practices, in line with structural and systemic violence in American society. [ABSTRACT FROM AUTHOR]

BACKGROUND: Sightseeing operations are characterized by the presence of passengers as well as favorable light and weather conditions. They include both fixed-wing aircraft and helicopters, an aspect that allows for a comparison of these two types of aircraft in similar operations. METHODS: A total of 95 accident reports from 2008 until 2018 were extracted from the NTSB online database, with each mentioning commercial sightseeing as their operation. RESULTS: O ut of a total of 95 accidents, 16 were fatal with a total of 58 people suffering fatal injuries. On average 3.625 people died in each fatal accident. There were significantly more accidents in Alaska and Hawaii than expected. There were significantly more accidents caused by the maintenance crew in helicopters than in airplanes, but significantly more pilot-related accidents in fixed-wing aircraft compared to helicopters. Despite favorable light and weather conditions, 37 accidents reported the environment as a contributing factor to the accident. CONCLUSION: Sightseeing accidents show a pronounced difference between helicopters and airplane accidents that point to different approaches when improving safety in either category. Although night and instrument meteorological conditions are largely absent in the dataset, wind conditions and unsuitable terrain are frequently mentioned. The experience of the pilots and the specific geography of the sightseeing area are likely to affect operational safety the most. The specific dangers of unsuitable terrain affect both helicopters and fixed-wing operations and may be assuaged by specific training or briefings. [ABSTRACT FROM AUTHOR]

Lieutenant General Charles Muriu Kahariri has been promoted to the rank of General and appointed Chief of Defence Forces in Kenya, following the death of Gen Francis Ogolla. Maj‐Gen John Mugaravai Omenda has been promoted to the rank of Lt‐Gen and named Vice Chief of Defence Forces, while Maj‐Gen Fatuma Gaiti Ahmed has become the first woman service commander as Kenya Air Force Commander. Other appointments include Maj‐Gen Thomas Ng'ang'a as Deputy Vice‐Chancellor at the National Defence University‐Kenya, and Brigadier Peter Nyamu Githinji as Senior Directing Staff, Air at the National Defence College. Additionally, a high-level meeting in Somalia discussed a draft defence agreement between Somalia and Kenya, aiming to enhance cooperation in areas such as intelligence sharing and joint military operations. [Extracted from the article]

Egypt's President Abdel Fattah al-Sisi has expressed his condolences for the deaths of Iranian President Ebrahim Raisi and Foreign Minister Hossein Amir-Abdollahian in a helicopter crash. Al-Sisi, who has been working towards normalizing relations with Iran, extended his sympathies to the Iranian people and expressed solidarity with Iran in their loss. Egypt and Iran have been seeking to improve their strained ties, with diplomatic exchanges increasing in recent months. South Africa's President Cyril Ramaphosa also expressed regret over Raisi's death, highlighting the strong bilateral relations between South Africa and Iran. [Extracted from the article]

As the major energy absorption of helicopter in crash, the buffer plays an important role in the safety flight of helicopter. A combined oleo-pneumatic and foam-aluminum helicopter buffer is proposed in this paper. Based on the theoretical calculation model of plastic collapse stress and finite element model, the impact crushing stress-strain of single aluminum foam is calculated and simulated. Then the calculation and simulation results are verified. Furthermore, the theory and simulation model are verified by impact crushing test of single aluminum foam. The dynamic characteristics curve of aluminum foam collapse is integrated into the dynamic model of combined oleo-pneumatic and foam-aluminum landing gear, and the crashworthiness performance simulation analysis is carried out. The results show that the peak load of the combined oleo-pneumatic and foam-aluminum buffer is reduced by 38%, and the buffer efficiency is increased by 12.7%. The crashworthiness performance of helicopter landing gear buffer is improved effectively. [ABSTRACT FROM AUTHOR]

Loss of tail rotor effectiveness (LTE) is an unstable dynamic phenomenon that affects single-rotor helicopters and frequently leads to accidents. LTE accidents recur with troubling regularity and show no sign of abatement. This work uncovers new data-driven findings pertaining to LTE and risk factors. First, a scorecard is developed covering a broad range of results to better understand LTE accidents. Second, the risk of LTE is derived for current helicopters. Third, a Deep Learning model is developed that captures the dependence between LTE risk and helicopter features. A danger zone is discovered in the design space for short tail rotor arm and high tail rotor RPM. The results challenge the prevailing narrative of LTE accidents as mere pilot errors and demonstrate an intrinsic propensity to these accidents is embedded in part in the helicopter design. The findings open the door to new, more effective safety interventions for LTE accident prevention. [ABSTRACT FROM AUTHOR]

With enlargement of costs of training and hazards, and high responsibility of job, importance of proper selection of pilots is huge. The nature of flight mission can be equally important factor for selection, so as different abilities and test results. On the sample of 50 pilots of different types of helicopter missions (military, police and commercial) without accidents in career, pilots had to make assessment about traits which are high important for successful helicopter pilot, and then make self - assessment based on five point Likert scale. Data were processed by fuzzy - DEMATEL and fuzzy - TOPSIS methods. Quantitative and qualitative differences in assessment of personality traits for successful helicopter pilots between three branches were found. [ABSTRACT FROM AUTHOR]

Many lives and aircrafts have been lost due to human errors associated with mental workload overload (MWLOL). Human errors are successfully considered in existing Fault Tree Analysis (FTA) methods. However, MWLOL is considered through Performance Shaping Factors indirectly and its information is hidden in FT construction, which is not conducive to analyze the root causes of human errors and risks. To overcome this difficulty, we develop a risk analysis method where Multiple Resources Model (MRM) is incorporated into FTA methods. MRM analyzes mental workload by estimating the resources used during performing concurrent tasks, probably including abnormal situation handling tasks introduced by basic events in FT. Such basic events may cause MWLOL and then trigger corresponding human error events. A MWLOL gate is proposed to describe MWLOL explicitly and add these new relationships to traditional FT. This new method extends previous FTA methods and provides a more in-depth risk analysis. An accident, a helicopter crash in Maryland, is analyzed by the proposed method. [ABSTRACT FROM AUTHOR]

The Multinational Force and Observers in Sinai is a 13-nation international peacekeeping organization with the mission to implement the security provisions of the 1979 Egyptian–Israeli Treaty of Peace and continues today after approximately four decades. Despite not having significant changes to its core mission of force health protection, the medical team has recently evolved to face several challenges, with a coronavirus pandemic and a fatal helicopter crash. This article describes the medical challenges and experiences of the medical team from August 2019 to December 2020, highlighting changes from previous years. This article also updates three previous articles on the subject published in Military Medicine in 1983, 1991, and 2003. [ABSTRACT FROM AUTHOR]