A Study on the Design of Isolator and the Mounting Method for Reducing the Pyro-Shock of a MEMS IMU.

In this paper, we proposed two methods for reducing the pyro-shock of the MEMS Inertial Measurement Unit (IMU). First, we designed the vibration isolator for reducing the pyro-shock inside the IMU. However, it turned out that there is a limit to reducing the pyro-shock with only the vibration isolator. Therefore, we improved the pyro-shock reduction performance by changing the method of mounting on the flight vehicle. Four mounting options were tested and one of them was adopted. The results showed the best reduction performance when we designed the vibration isolator with an aluminum integrated structure. When mounting, two methods were applied. One was to insert a bracket with a different material between the mounting surface and IMU and the other was to insert a set of three washers that was stacked in a PEEK-metal-PEEK order at each part of the screw connections.

Cabin crew health and fitness-to-fly: Opportunities for re-evaluation amid COVID-19.

Aircrew fitness-to-fly is among the elements that make aviation the safest form of long-distance transport. The health of cabin crew is a crucial determinant in carrying out safety-related duties. 'Fitness-to-fly' is associated with defined workplace conditions, for which airlines have a legal duty to ensure fitness for employment. We explored the literature on fitness-to-fly to obtain a pragmatic assessment of the challenges for aeromedical examinations. Regulations promulgated by aviation regulatory authorities and airline-internal policies have similar status and meaning, yet there is no harmonised approach internationally, and an inability to conform periodic medical assessments to actual operational fitness. The COVID-19 pandemic has highlighted the need to better understand fitness-to-fly criteria. Fitness-to-fly measures are mainly based on self-reported data and there is a need for a 'safety' factor for self-reports. Aeromedical evaluations should evolve from meeting medical standards to include pandemics as an element of the overall risk of aircraft operations. Re-evaluating criteria for fitness-to-fly assessment will further the goal of linking research to the actual needs of public health decisionmakers. If airlines are to resume operations at pre-pandemic levels, they must demonstrate to the public and public health agencies that fitness-to-fly assessment is appropriate and effective.

Transport of COVID-19 and other highly contagious patients by helicopter and fixed-wing air ambulance: a narrative review and experience of the Swiss air rescue Rega.

BACKGROUND: The current COVID-19 pandemic highlights the challenges air ambulance services are facing when transporting highly infectious patients for several hours in enclosed spaces. This overview provides an example of a standard operating procedure (SOP) for infection prevention measures in HEMS missions during the COVID-19 pandemic. Furthermore, we describe different methods used by several organizations in Europe and the experience of the Swiss air rescue organization Rega in transporting these patients. Possible benefits of the use of small patient isolation units (PIU) are discussed, including the fact that accompanying medical personnel do not need to wear personal protective equipment (PPE) during the transport but can still maintain full access to the patient. Rega has developed and patented its own PIU. This device allows spontaneously breathing or mechanically ventilated patients to be transported in pressurized jet cabins, small helicopters and ambulance vehicles, without the need to change between transport units. This PIU is unique, as it remains air-tight even when there is a sudden loss of cabin pressure. CONCLUSION: A wide variety of means are being used for the aeromedical transport of infectious patients. These involve isolating either the patient or the medical crew. One benefit of PIUs is that the means of transport can be easily changed without contaminating the surroundings and while still allowing access to the patient.

Flight safety assessment based on an integrated human reliability quantification approach.

Human error is an important risk factor for flight safety. Although the human error assessment and reduction technique (HEART) is an available tool for human reliability derivation, it has not been applied in flight safety assessment. The traditional HEART suffers from imprecise calculation of the assessed proportion of affect (APOA) because it heavily depends on a single expert's judgment. It also fails to provide remedial measures for flight safety problems. To overcome these defects of the HEART, this study proposes an integrated human error quantification approach that uses the improved analytic hierarchy process method to determine the APOA values. Then, these values are fused to the HEART method to derive the human error probability. A certain flight task is completed to assess human reliability. The results demonstrate that the proposed method is a reasonable and feasible tool for quantifying human error probability and assessing flight safety in the aircraft manipulation process. In addition, the critical error-producing conditions influencing flight safety are identified, and improvement measures for high-error-rate operations are provided. The proposed method is useful for reducing the possibility of human error and enhancing flight safety levels in aircraft operation processes.

Budgerigars adopt robust, but idiosyncratic flight paths.

We have investigated the paths taken by Budgerigars while flying in a tunnel. The flight trajectories of nine Budgerigars (Melopsittacus undulatus) were reconstructed in 3D from high speed stereo videography of their flights in an obstacle-free tunnel. Individual birds displayed highly idiosyncratic flight trajectories that were consistent from flight to flight over the course of several months. We then investigated the robustness of each bird's trajectory by interposing a disk-shaped obstacle in its preferred flight path. We found that each bird continued to fly along its preferred trajectory up to a point very close to the obstacle before veering over the obstacle rapidly, making a minimal deviation to avoid a collision, and subsequently returning to its original path. Thus, Budgerigars show a high propensity to stick to their individual, preferred flight paths even when confronted with a clearly visible obstacle, and do not adopt a substantially different, unobstructed route. The robust preference for idiosyncratic flight paths, and the tendency to pass obstacles by flying above them, provide new insights into the strategies that underpin obstacle avoidance in birds. We believe that this is the first carefully controlled study of the behaviour of birds in response to a newly introduced obstacle in their flight path. The insights from the study could also have implications for conservation efforts to mitigate collisions of birds with man-made obstacles.

Analysis of development and evolution rules of civil aviation in China based on life cycle theory.

The development of CAAC began in the early days of 1949. From a comparatively less popular means of transport to the world's second largest by volume, this means of transport has undergone major and minor changes in the last 70 years. It is not known whether there are significant laws in the process of development. For this reason, we analyze the statistical indicators of the development of civil aviation transport and select representative indicators, namely, the total turnover of transport, the number of routes, the number of aircraft, the number of transport aircraft, and the number of domestic city connections. At the same time, the life cycle theory is introduced, and the typical growth curve model is used to fit the data. It is found that the evolution life cycle of civil aviation in China can be divided into three stages: the first life cycle stage from 1950 to 1981, the second from 1982 to 2003, and the third from 2004 to 2017. Each life cycle follows the growth characteristics of occurrence, growth and maturity, and each life cycle has a time range of approximately 30 years. At present, China's civil aviation industry is in the period of rapid growth in the third life cycle. This industry is expected to reach maturity in approximately 2026 and then to begin to grow slowly. Relevant departments can adopt corresponding development strategies to guide the smooth development of civil aviation in accordance with the growth law of the development and evolution life cycle of civil aviation in China.

Piezoelectric Transducer-Based Structural Health Monitoring for Aircraft Applications.

Structural health monitoring (SHM) is being widely evaluated by the aerospace industry as a method to improve the safety and reliability of aircraft structures and also reduce operational cost. Built-in sensor networks on an aircraft structure can provide crucial information regarding the condition, damage state and/or service environment of the structure. Among the various types of transducers used for SHM, piezoelectric materials are widely used because they can be employed as either actuators or sensors due to their piezoelectric effect and vice versa. This paper provides a brief overview of piezoelectric transducer-based SHM system technology developed for aircraft applications in the past two decades. The requirements for practical implementation and use of structural health monitoring systems in aircraft application are then introduced. State-of-the-art techniques for solving some practical issues, such as sensor network integration, scalability to large structures, reliability and effect of environmental conditions, robust damage detection and quantification are discussed. Development trend of SHM technology is also discussed.

E-cigarettes in airports and on flights: Europe and the US. / Cigarrillos electrónicos en aeropuertos y en vuelos: Europa y EEUU.

BACKGROUND: While progress has been made to create smoke-free airports, sales of e-cigarettes at airports and airplanes and the presence of advertisements might detract from these smoke-free policies. The objective of this study is to describe the presence of policies, advertising, sales and use of e-cigarettes in airports and on flights in Europe and the US. METHODS: A cross-sectional study was conducted between March-May, 2014. The study included 21 large and mid-sized airports of Europe and the US as well as 19 flights. A standardised protocol was used to observe points of sales and advertisements and to collect information on the implementation of policies on e-cigarette use. In addition, a series of questions were developed to obtain policy details from airport personnel and flight attendants. RESULTS: Retail outlets selling e-cigarettes in airports were present in approximately 20% and 40% of the observed pre and post-security areas, respectively. In post-security, 27.8% of the airport staff reported that the use of e-cigarettes indoors was not allowed, 22.2% reported that they did not know, 27.8% reported that it was only allowed in the smoking room, and 22.2% reported that it was allowed anywhere. Smoking ban announcements were made on all flights. However, only 15.8% of the flights made a specific announcement regarding the ban of using e-cigarettes. Conclusions. In light of our results, it seems necessary to reinforce in-flight e-cigarette smoking ban announcements and to instruct airport employees about the existence of e-cigarette smoking policies. Furthermore, airports themselves should also be encouraged to adopt smoke-free policies.

Antecedentes. Pese a los avances en las políticas libres de humo en los aeropuertos, las ventas de cigarrillos electrónicos en aeropuertos y aviones y la presencia de publicidad pueden suponer un paso atrás en la implementación de dichas políticas. El objetivo de este estudio es describir la presencia de políticas, publicidad, ventas y el uso de cigarrillos electrónicos en aeropuertos y en vuelos de Europa y los EE.UU.Métodos. Estudio transversal realizado entre marzo y mayo del año 2014. El estudio incluyó 21 aeropuertos grandes y medianos de Europa y los EE.UU., así como 19 vuelos. Se utilizó un protocolo estandarizado para observar puntos de venta y publicidad y se recogió información sobre la implementación de políticas sobre el uso de cigarrillos electrónicos. Además, obtuvo información más detallada del personal del aeropuerto y de los asistentes de vuelo sobre las políticas de uso de cigarrillo electrónicos.Resultados. Los puntos de venta de cigarrillos electrónicos en los aeropuertos estaban presentes en aproximadamente el 20% y el 40% de las áreas observadas antes y después del control de seguridad, respectivamente. Después del control, el 27,8% del personal del aeropuerto declaró que no estaba permitido el uso los cigarrillos electrónicos en el interior, el 22,2% declaró que no sabía si se podían usar, el 27,8% declaró que sólo estaba permitido en el área de fumadores y el 22,2% declaró que se podía fumar en cualquier parte. Todos los vuelos anunciaron la prohibición de fumar. Sin embargo, sólo el 15,8% de los vuelos específicamente anunció la prohibición de usar cigarrillos electrónicos.Conclusiones. Nuestros resultados muestran que sería necesario reforzar los avisos de prohibición del uso de cigarrillos electrónicos durante los vuelos y de instruir a los empleados del aeropuerto sobre la existencia de políticas sobre el uso de cigarrillos electrónicos. Además, también se debería promover políticas libres de humo sin excepciones en todos los aeropuertos.

Investigating the potential for transisomerisation of trycresyl phosphate with a palladium catalyst and its implications for aircraft cabin air quality.

The quality of aircraft cabin air has been an area of concern for several decades. Many investigations have linked the presence of organophosphates in air to Aerotoxic Syndrome with adverse symptoms reported by thousands of aircraft crew across the globe. Currently the source of organophosphates has been under debate, with studies pointing towards tricresylphosphates (TCP) in aircraft oil as the main source due to leaks in engine seals resulting in fumes entering the cabin. However, comparisons of oil and cabin samples have shown that the cabin samples contain a much higher proportion of ortho-substituted TCP than is commonly detected in oil. The aim of this experiment was to investigate the potential for palladium catalysts (present in aircraft air conditioning systems) to convert meta- and para-substituted TCP to produce ortho-substituted TCP through transisomerisation. This experiment was performed in a controlled laboratory setting aimed to represent the conditions likely to be experienced in aircraft. Samples were introduced to a stainless steel micro reactor tube containing the pelletized palladium catalyst using a HPLC pump with a 0.2 ml/min feed flow rate. The temperature maintained at 400 °C over a period of 1 h and samples collected using a condensing vesicle. These were then diluted and transferred to a 2 mL vial for analysis by gas chromatography mass spectrometry. No evidence supporting the transisomerisation of tricresylphosphate was obtained. This indicates that more emphasis should be placed on identifying other potential sources of ortho substituted TCP.

Cigarrillos electrónicos en aeropuertos y en vuelos: Europa y EEUU / E-cigarettes in airports and on flights: Europe and the US

Antecedentes. Pese a los avances en las políticas libres de humo en los aeropuertos, las ventas de cigarrillos electrónicos en aeropuertos y aviones y la presencia de publicidad pueden suponer un paso atrás en la implementación de dichas políticas. El objetivo de este estudio es describir la presencia de políticas, publicidad, ventas y el uso de cigarrillos electrónicos en aeropuertos y en vuelos de Europa y los EE.UU. Métodos. Estudio transversal realizado entre marzo y mayo del año 2014. El estudio incluyó 21 aeropuertos grandes y medianos de Europa y los EE.UU., así como 19 vuelos. Se utilizó un protocolo estandarizado para observar puntos de venta y publicidad y se recogió información sobre la implementación de políticas sobre el uso de cigarrillos electrónicos. Además, obtuvo información más detallada del personal del aeropuerto y de los asistentes de vuelo sobre las políticas de uso de cigarrillo electrónicos. Resultados. Los puntos de venta de cigarrillos electrónicos en los aeropuertos estaban presentes en aproximadamente el 20% y el 40% de las áreas observadas antes y después del control de seguridad, respectivamente. Después del control, el 27,8% del personal del aeropuerto declaró que no estaba permitido el uso los cigarrillos electrónicos en el interior, el 22,2% declaró que no sabía si se podían usar, el 27,8% declaró que sólo estaba permitido en el área de fumadores y el 22,2% declaró que se podía fumar en cualquier parte. Todos los vuelos anunciaron la prohibición de fumar. Sin embargo, sólo el 15,8% de los vuelos específicamente anunció la prohibición de usar cigarrillos electrónicos. Conclusiones. Nuestros resultados muestran que sería necesario reforzar los avisos de prohibición del uso de cigarrillos electrónicos durante los vuelos y de instruir a los empleados del aeropuerto sobre la existencia de políticas sobre el uso de cigarrillos electrónicos. Además, también se debería promover políticas libres de humo sin excepciones en todos los aeropuertos

Background. While progress has been made to create smoke-free airports, sales of e-cigarettes at airports and airplanes and the presence of advertisements might detract from these smoke-free policies. The objective of this study is to describe the presence of policies, advertising, sales and use of e-cigarettes in airports and on flights in Europe and the US. Methods. A cross-sectional study was conducted between March-May, 2014. The study included 21 large and mid-sized airports of Europe and the US as well as 19 flights. A standardised protocol was used to observe points of sales and advertisements and to collect information on the implementation of policies on e-cigarette use. In addition, a series of questions were developed to obtain policy details from airport personnel and flight attendants. Results. Retail outlets selling e-cigarettes in airports were present in approximately 20% and 40% of the observed pre and post-security areas, respectively. In post-security, 27.8% of the airport staff reported that the use of e-cigarettes indoors was not allowed, 22.2% reported that they did not know, 27.8% reported that it was only allowed in the smoking room, and 22.2% reported that it was allowed anywhere. Smoking ban announcements were made on all flights. However, only 15.8% of the flights made a specific announcement regarding the ban of using e-cigarettes. Conclusions. In light of our results, it seems necessary to reinforce in-flight e-cigarette smoking ban announcements and to instruct airport employees about the existence of e-cigarette smoking policies. Furthermore, airports themselves should also be encouraged to adopt smoke-free policies

Field study of neutrality cabin temperature for Chinese passenger in economy class of civil aircraft.

Cabin thermal comfort is an important factor for the competitiveness of civil aviation. It has become a hot topic in recent years. However, there are still no clear standards for the thermal comfort in the aircraft cabin. In this paper, the cabin thermal comfort of passengers in 30 flights was investigated. Both objective and subjective data were collected in order to obtain a neutrality cabin temperature, Tnc. The investigation shows that the distribution of Thermal Sensation Votes (TSVs) was approximately symmetric around the "Neutral" vote. The clothing insulation value of passengers, ICLO, was affected by the outdoor mean new effective temperature of departure city, ET*. Tnc also changed with the outdoor ET*. According to this field surveys, a linear relationship is built between Tnc and ET* as an adaptive model for the civil aircraft cabin. This adaptive model can be used as a reference to control the cabin operative temperature around the passengers. In this way, the cabin thermal comfort requirement may be satisfied for most of the passengers.

Integrated optimization of unmanned aerial vehicle task allocation and path planning under steady wind.

Wind has a significant effect on the control of fixed-wing unmanned aerial vehicles (UAVs), resulting in changes in their ground speed and direction, which has an important influence on the results of integrated optimization of UAV task allocation and path planning. The objective of this integrated optimization problem changes from minimizing flight distance to minimizing flight time. In this study, the Euclidean distance between any two targets is expanded to the Dubins path length, considering the minimum turning radius of fixed-wing UAVs. According to the vector relationship between wind speed, UAV airspeed, and UAV ground speed, a method is proposed to calculate the flight time of UAV between targets. On this basis, a variable-speed Dubins path vehicle routing problem (VS-DP-VRP) model is established with the purpose of minimizing the time required for UAVs to visit all the targets and return to the starting point. By designing a crossover operator and mutation operator, the genetic algorithm is used to solve the model, the results of which show that an effective UAV task allocation and path planning solution under steady wind can be provided.

Physiological predictors of Hypoxic Challenge Testing (HCT) outcomes in Interstitial Lung Disease (ILD).

BACKGROUND: Pre-flight risk assessments are currently recommended for all Interstitial Lung Disease (ILD) patients. Hypoxic challenge testing (HCT) can inform regarding the need for supplemental in-flight oxygen but variables which might predict the outcome of HCT and thus guide referral for assessment, are unknown. METHODS: A retrospective analysis of ILD patients attending for HCT at three tertiary care ILD referral centres was undertaken to investigate the concordance between HCT and existing predictive equations for prediction of in-flight hypoxia. Physiological variables that might predict a hypoxaemic response to HCT were also explored with the aim of developing a practical pre-flight assessment algorithm for ILD patients. RESULTS: A total of 106 ILD patients (69 of whom (65%) had Idiopathic Pulmonary Fibrosis (IPF)) underwent HCT. Of these, 54 (51%) patients (of whom 37 (69%) had IPF) failed HCT and were recommended supplemental in-flight oxygen. Existing predictive equations were unable to accurately predict the outcome of HCT. ILD patients who failed HCT had significantly lower resting SpO2, baseline PaO2, reduced walking distance, FEV1, FVC and TLCO, but higher GAP index than those who passed HCT. CONCLUSIONS: TLCO >50% predicted and PaO2 >9.42 kPa were independent predictors for passing HCT. Using these discriminators, a novel, practical pre-flight algorithm for evaluation of ILD patients is proposed.

Tripartite equilibrium strategy for a carbon tax setting problem in air passenger transport.

Carbon emissions in air passenger transport have become increasing serious with the rapidly development of aviation industry. Combined with a tripartite equilibrium strategy, this paper proposes a multi-level multi-objective model for an air passenger transport carbon tax setting problem (CTSP) among an international organization, an airline and passengers with the fuzzy uncertainty. The proposed model is simplified to an equivalent crisp model by a weighted sum procedure and a Karush-Kuhn-Tucker (KKT) transformation method. To solve the equivalent crisp model, a fuzzy logic controlled genetic algorithm with entropy-Bolitzmann selection (FLC-GA with EBS) is designed as an integrated solution method. Then, a numerical example is provided to demonstrate the practicality and efficiency of the optimization method. Results show that the cap tax mechanism is an important part of air passenger trans'port carbon emission mitigation and thus, it should be effectively applied to air passenger transport. These results also indicate that the proposed method can provide efficient ways of mitigating carbon emissions for air passenger transport, and therefore assist decision makers in formulating relevant strategies under multiple scenarios.

Unmanned aerial vehicles in construction and worker safety.

Applications of unmanned aerial vehicles (UAVs) for military, recreational, public, and commercial uses have expanded significantly in recent years. In the construction industry, UAVs are used primarily for monitoring of construction workflow and job site logistics, inspecting construction sites to assess structural integrity, and for maintenance assessments. As is the case with other emerging technologies, occupational safety assessments of UAVs lag behind technological advancements. UAVs may create new workplace hazards that need to be evaluated and managed to ensure their safe operation around human workers. At the same time, UAVs can perform dangerous tasks, thereby improving workplace safety. This paper describes the four major uses of UAVs, including their use in construction, the potential risks of their use to workers, approaches for risk mitigation, and the important role that safety and health professionals can play in ensuring safe approaches to the their use in the workplace.

The high and low comfort peaks in passengers' flight.

BACKGROUND: Knowing the high and low peaks in comfort during a flight could be useful in prioritizing aircraft interior improvements. OBJECTIVE: The first objective of this study was to identify whether there are differences in comfort experiences during different phases of a flight. The second objective of this study was to identify similarities between recalled and real time reported comfort experiences. METHODS: 149 participants were asked to rate the comfort in the different phases of their last flight on a scale from 1-10. Additionally, a combination of a self-reporting design probe and generative interview was used to investigate the appraisal patterns of emotions in nine passengers. RESULTS: The 149 subjects reported the highest comfort after take-off and arriving at the destination, the lowest while stowing the luggage and during the cruise flight. The qualitative long haul inflight study showed after take-off and while arriving at the destination the most positive emotions and during the cruise flight there is a negative experience phase. CONCLUSIONS: Suggestions are given to improve the cruise flight phase, by for example stimulation of movement or better service.

Concurrent Pilot Instrument Monitoring in the Automated Multi-Crew Airline Cockpit.

INTRODUCTION: Pilot instrument monitoring has been described as "inadequate," "ineffective," and "insufficient" after multicrew aircraft accidents. Regulators have called for improved instrument monitoring by flight crews, but scientific knowledge in the area is scarce. Research has tended to investigate the monitoring of individual pilots when in the pilot-flying role; very little research has looked at crew monitoring, or that of the "monitoring-pilot" role despite it being half of the apparent problem. METHODS: Eye-tracking data were collected from 17 properly constituted and current Boeing 737 crews operating in a full motion simulator. Each crew flew four realistic flight segments, with pilots swapping between the pilot-flying and pilot-monitoring roles, with and without the autopilot engaged. Analysis was performed on the 375 maneuvering-segments prior to localizer intercept. RESULTS: Autopilot engagement led to significantly less visual dwell time on the attitude director indicator (mean 212.8-47.8 s for the flying pilot and 58.5-39.8 s for the monitoring-pilot) and an associated increase on the horizontal situation indicator (18-52.5 s and 36.4-50.5 s). DISCUSSION: The flying-pilots' withdrawal of attention from the primary flight reference and increased attention to the primary navigational reference was paralleled rather than complemented by the monitoring-pilot, suggesting that monitoring vulnerabilities can be duplicated in the flight deck. Therefore it is possible that accident causes identified as "inadequate" or "insufficient" monitoring, are in fact a result of parallel monitoring.Jarvis SR. Concurrent pilot instrument monitoring in the automated multi-crew airline cockpit. Aerosp Med Hum Perform. 2017; 88(12):1100-1106.

Aircraft engine sensor fault diagnostics using an on-line OBEM update method.

This paper proposed a method to update the on-line health reference baseline of the On-Board Engine Model (OBEM) to maintain the effectiveness of an in-flight aircraft sensor Fault Detection and Isolation (FDI) system, in which a Hybrid Kalman Filter (HKF) was incorporated. Generated from a rapid in-flight engine degradation, a large health condition mismatch between the engine and the OBEM can corrupt the performance of the FDI. Therefore, it is necessary to update the OBEM online when a rapid degradation occurs, but the FDI system will lose estimation accuracy if the estimation and update are running simultaneously. To solve this problem, the health reference baseline for a nonlinear OBEM was updated using the proposed channel controller method. Simulations based on the turbojet engine Linear-Parameter Varying (LPV) model demonstrated the effectiveness of the proposed FDI system in the presence of substantial degradation, and the channel controller can ensure that the update process finishes without interference from a single sensor fault.