Instrument Flight Rules Research Articles

HELICOPTER PROCEDURE DESIGN FOR AIR TRAFFIC MOVEMENT IMPROVEMENT: A CASE OF KERTAJATI INTERNATIONAL AIRPORT

A review of Aeronautical Information Publication Indonesia Volume II indicates a critical infrastructure deficiency at Kertajati International Airport. The absence of a designated helipad presents a significant obstacle for air traffic controllers. This research proposed helicopter procedures designed for instrument flight rules to improve air traffic movement at Kertajati International Airport. A qualitative approach using interviews and document analysis was employed. The research identified a critical omission: the absence of designated helicopter take-off and landing locations. This lack of a framework hinders safe and efficient traffic management. The proposed procedure addresses this challenge by providing a structured approach for managing mixed rotary-wing and fixed-wing traffic, potentially reducing human error and delays, and fostering informed decision-making by air traffic controllers.

All's well that ends well? Outcome bias in pilots during instrument flight rules

AbstractThe objective of the present study was to examine if the Outcome Bias also occurs in pilots flying under instrument flight rules (IFR). In a scenario‐based survey, 60 pilots evaluated weather‐related decisions made by hypothetical pilots. Participants rated the decisions as better, less risky, and regarded the probability that they would have made the same decision as higher when they were followed by a positive outcome, than when they were followed by a negative outcome. This effect showed likewise for novice pilots and for experienced pilots. These findings could be relevant for the flight‐related decision‐making of pilots, which sometimes is affected by the decisions made by third‐party pilots. In particular, decisions made by other pilots that have led to positive outcomes might be hastily followed, whereas those that have led to negative outcomes might be hastily rejected.

Analysis of Airport Optimal Location in Papua Province as a Support for Logistics Center Distribution Development

Papua is the largest province in Indonesia. It covers an area of 316,552.6 km2. Papua Province consists of 28 regencies and one city, with a population of 4.03 million in 2020. The main mode of transportation as a link between regions in this province is air transportation, in addition to the development of sea transportation through the Sea Toll program and land transportation with the construction of the Trans Papua Road. This study takes the point of view of the transportation network, especially for air transportation, as the mode of choice backbone of the logistics distribution in the Papua area. Considering these conditions, this study considers that the airport is a logistics node, so it is necessary to inventory the number of airports in Papua Province. The method of this study was the shortest path which was included in a network model for determining the shortest and various routes. It analyzed the answers to questions such as which one will be the shortest, fastest, or cheapest route to go to a location and determined locations for logistics facilities, such as distribution centers and warehouses. The study's results were the object of this research is the airport listed on the website. Analysis of the shortest route between airports in the Instrument Flight Rules (IFR) Route Papua area network produced a distance matrix between airports. It resulted four scenarios of the number of airports and their respective service areas.

50 & 25 Years Ago

Application of Digital Computers to Air Traffic Control in the United States; Howard J. Kirshner (p. 14): “Radar-oriented tracking and alphanumeric display systems using digital computers are just now emerging as the key data processing tool in air traffic control, although the Great Falls Center, using air defense computer and display facilities, has been in operation since 1963.” (p. 15) “Aircraft operations in the United States are conducted under two forms of ATC procedures. The first procedure is called Visual Flight Rules, or VFR, and the second, Instrument Flight Rules, or IFR. … Under Visual Flight Rules, it is the responsibility of the aircraft’s pilot to maintain adequate separation from other aircraft. … The ground-based ATC system is responsible for providing separation among aircraft flying under IFR, although in clear weather the pilot also has a responsibility to see and avoid other traffic, since not all aircraft in most segments of low-altitude airspace will be under control of the ground system.” (p. 16) “At 61 locations having radars and beacons, the computer-based Advanced Radar Terminal System (ARTS) is being deployed.” [Editor’s note: The article describes in detail the use of computers to analyze and display information that is captured by radar and beacon facilities. The impression is that none of these systems is yet (1972) ready for use but will become available soon.]

Analysis of Saturated Capacity on the Runway Based on Advisory Circular 150/5060-5 As a Study Material for Airport Management Learning

The demand for air transportation from year to year until 2018 continues to increase. However, in 2019 it decreased as a result of the increase in air ticket fares, as well as in 2020 as a result of the COVID-19 pandemic. Although demand is experiencing a decline, knowing airport capacity is important in airport planning, which is one of the disciplines studied in airport management. Therefore, this research aims to estimate the saturation capacity of the runway at Sultan Mahmud Badaruddin International Airport (SMB) II, using the method developed by the Federal Aviation Administration (FAA) and specified in the Advisory Circular 150/5060-5. The results of this study can be used as study material in learning the field of airport management science. Based on the data obtained and processed, the results show that the saturation capacity of the runway per hour for runway 11 directions is 53 for Visual Flight Rules (VFR) and 49 Instrument Flight Rules (IFR). Meanwhile, the direction of runway 29 is 50 in VFR conditions and 46 in IFR conditions. So that the average saturation capacity for both runway directions is 51 in VFR conditions and 48 in IFR conditions. This runway capacity calculation method cannot accommodate differences in the flight separation rules applied, so that this capacity will be achieved if Airnav Indonesia, Palembang Branch as the manager of flight navigation services at SMB II Airport applies the same rules as the FAA. The currently applied separation rules are relatively larger than those set by the International Civil Aviation Organization (ICAO) and also the FAA. As an ICAO member country, it is still possible to lower the separation rules set by ICAO to increase runway capacity.The conclusions of the research have been obtained from the analysis of the saturated capacity of the runway based on the advisory circular 150/5060-5 which has been used as a study material for learning in the field of airport management science.

Availability of en-route alternate aerodromes as potential limitation in flight planning for hybrid-electric regional aircraft

To reduce carbon emissions, hybrid-electric aircraft could replace conventional turboprop aircraft on regional operations. Because of the limited energy density provided by batteries and requirements concerning reserves for operations under instrument flight rules (IFR), a range extender will be required to achieve commercially relevant ranges. In a serial hybrid concept with electric motors driving propellers, a gas turbine in combination with a generator would provide sufficient electricity for longer ranges, on top of the energy stored in the batteries. It is advantageous that the initial flight stages of missions beyond the battery-electric range are operated with the range extender, with battery power reserved for the final part of the mission. If the gas turbine fails, full battery power will remain available to return to the origin airport, to reach the planned destination or to divert to a suitable en-route alternate airport. Therefore, in cases of longer missions, flight planning must consider the availability of alternate en-route airports within the remaining battery-electric range of the aircraft. This paper examines whether the requirement to reach an alternate airport within the remaining battery electric range in case of a failure of the gas turbine / generator is a major constraint on hybrid-electric aircraft operations. For this purpose, actual airport pairs operated by larger regional turboprop aircraft (ATR42/72 and Dash 8-400) as listed in global flight schedules for the year 2019 are analyzed. The authors find that only a small fraction of routes is constrained by the availability of en-route alternate airports, but this result depends on the battery-electric range, for which a sensitivity analysis has been conducted. Minimizing operational constraints can be an important factor for the acceptance and market uptake of new aircraft concepts.

GA Pilot Perceptions of Speech Systems to Transcribe and Submit PIREPs

Flying into hazardous weather can be a cause of aviation incidents and accidents. Accidents involving general aviation (GA) pilots who are not instrument rated who fly into instrument meteorological conditions (IMC) are often fatal. Pilot weather reports (PIREPs) can increase the accuracy and timeliness of current and forecasted weather conditions. They are an essential tool used by pilots to avoid flying into hazardous weather as well as meteorologists to develop and update aviation forecasts. Thus, a large number of accurate PIREPs with the best source of current weather coming from pilots and air traffic controllers are needed. Pilots are often unable to make PIREPs because of workload in the cockpit or because it is cumbersome to leave the air traffic control (ATC) frequency to contact flight the flight service station (FSS). Currently, air traffic controllers must solicit and disseminate PIREPs. However, air traffic controllers’ primary obligation is to provide traffic separation and traffic alerts. During poor weather, when PIREPs are needed the most, controllers are often too busy to solicit and disseminate PIREPs (NTSB, 2017a). This study administered a descriptive survey to inquire about how likely pilots would be to use a speech recognition system (SRS) to transcribe and submit PIREPs automatically while flying in three distinct flight regimes: instrument flight rules (IFR), visual flight rules (VFR) with flight following, and VFR without flight following. The survey employed cross-section design and included Likert scale questions. For each flight regime, additional information was obtained through an open-ended follow-up question. The Likert scale responses indicated that pilots were neutral about using a SRS to transcribe and submit PIREPs in each flight regime.Spradley’s (1979) domain analysis was used to identify common themes and patterns from the open-ended responses. Major findings from flying IFR were that pilots found it easier to speak directly to air traffic control, or pilots were too busy to submit PIREPs while flying IFR. Major findings from flying VFR with flight following were that pilots thought it was easier to report PIREPs directly to air traffic control or to a flight service station, and it was more accurate to report PIREPs directly to an aviation professional. However, they were willing to try a SRS. Major findings from flying VFR without flight following were that pilots wanted the opportunity to review a PIREP submission for accuracy and were willing to try the system. Significant differences were determined by making a comparison between the three groups.

Investigation of Pilots' Visual Entropy and Eye Fixations for Simulated Flights Consisted of Multiple Take-Offs and Landings

Eye movement characteristics might provide insights on pilots' mental fatigue during prolonged flight. The visual entropy, eye fixation numbers, and eye fixation durations of ten novice pilots and ten expert pilots were analyzed for a four-hour simulated flight task consisting of four consecutive flight legs. Each flight leg lasted approximately one hour and contained five flight phases: takeoff, climb, cruise, descend, and landing. The pilots maneuvered the simulated B-52 aircraft following instrument flight rules (IFR) in a moderate-fidelity Microsoft Flight Simulator environment. Our results indicate that experts’ eye movement characteristics were significantly different from those of novices. In detail, novices' eye movements were more random, produced longer eye fixation durations, and had fewer eye fixation numbers on the areas of interest (AOIs) than the experts. In addition, the repetitive task (i.e., four consecutive flights) significantly impacted the eye movement characteristics for both experts and novices. Visual entropy and eye fixation duration increased, while eye fixation numbers decreased for both groups as the repetition index increased. Finally, the flight phases also affected eye movement characteristics. The results show that both experts' and novices' visual entropies were relatively higher during climb, cruise, and descend phases, whereas those were relatively lower during the takeoff and landing phases. The present results provide a foundation for us to better understand the similarities and dissimilarities of eye movement characteristics between the experts and novices for a prolonged flight. Lastly, potential scaffolding training methods and pilot anomaly alerting systems, derived from such eye movements, are introduced.

Optimization of Safety Critical IFR Helicopter Trajectories in Alpine Areas using MILP

Currently, helicopter operations according to Instrument Flight Rules (IFR) consist of high-altitude trajectories where the probability of collision with terrain is assumed to be very low. In such high altitudes, the risk of icing has to be considered, additionally, the flight time is unnecessarily long. Therefore, this paper elaborates on an optimization approach to find helicopter trajectories minimizing both flight time and height above terrain. To ensure safe operations, an iso-probability surface is calculated using collision probabilities, representing a surface above which the probability of collision with terrain is smaller than a chosen safety level. The optimization problem is solved using Mixed Integer Linear Programming (MILP). To evaluate the resulting trajectories the time until collision is evaluated for each waypoint, using a time-to-go approach based on Monte-Carlo simulations. The optimization with MILP yields feasible trajectories fulfilling a chosen safety level. Although the approach is computationally expensive, it serves as a basis for further research on these kinds of trajectory optimization applications.

A Bayesian Approach on Investigating Helicopter Emergency Medical Fatal Accidents.

INTRODUCTION: Helicopter Emergency Medical Service (HEMS) is a mode of transportation designed to expedite the transport of a patient. Compared to other modes of emergency transport and other areas of aviation, historically HEMS has had the highest accident-related fatality rates. Analysis of these accident data has revealed factors associated with an increased likelihood of accident-based fatalities. Here we report the results of an analysis on the likelihood of a fatality based on various factors as a result of a HEMS accident, employing a Bayesian framework.METHODS: A retrospective study was conducted using data extracted from the NTSB aviation accident database from April 31, 2005, to April 26, 2018. Evidence from Baker et al. (2006) was also used as prior information spanning from January 1, 1983, to April 30, 2005.RESULTS: A Bayesian logistic regression was implemented using the prior information and current data to calculate a posterior distribution confidence interval of possible values in predicting accident fatality. The results of the model indicate that flying at night (OR 3.06; 95 C.I 2.14, 4.48; PoD 100), flying under Instrument Flight Rules (OR 7.54; 95 C.I 3.94, 14.44; PoD 100), and post-crash fires (OR 18.73; 95 C.I 10.07, 34.12; PoD 100) significantly contributed to the higher likelihood of a fatality.CONCLUSION: Our results provide a comprehensive analysis of the most influential factors associated with an increased likelihood of a fatal accident occurring. We found that over the past 35 yr these factors were consistently associated with a higher likelihood of a fatality occurring.Simonson RJ, Keebler JR, Chaparro A. A Bayesian approach on investigating helicopter emergency medical fatal accidents. Aerosp Med Hum Perform. 2021; 92(7):563569.

Airspace design for integrating RPAS into terminal airspace

PurposeThis paper aims to analyse remotely piloted aircraft system (RPAS) integration in non-segregated terminal airspace. This work aims to identify the potential airspace volumes where a free operation of RPAS can be developed by analysing the airspace design of the terminal airspace.Design/methodology/approachThe methodology considers five crucial elements of the airspace design: obstacles, prohibited, restricted and dangerous zones, aerodrome zones, departing and arriving procedures and visual corridors. Free operation of RPAS is performed in those airspace volumes that no interaction with instrumental flight rules (IFR) flights is expected. Free RPAS airspace volumes are separated through current IFR separation minima.FindingsThe results show there is a significant amount of available airspace that RPAS can operate without interaction with conventional aircraft. The more significant risks are allocated by the limitations imposed by departing and arriving procedures in the terminal airspace.Research limitations/implicationsThe methodology is applied to medium-dense terminal airspace. This work assumes RPAS can perform visual or instrumental flights.Originality/valueRPAS is a capital issue for the majority of aviation actors. This work underlay the further development of a methodology regarding airspace design for RPAS in a terminal control area.

Variational assimilation of web camera-derived estimates of visibility for Alaska aviation

Abstract The Real Time Mesoscale Analysis (RTMA), a two-dimensional variational analysis algorithm, is used to provide hourly analyses of surface sensible weather elements for situational awareness at spatial resolutions of 3 km over Alaska. In this work we focus on the analysis of horizontal visibility in Alaska, which is a region prone to weather related aviation accidents that are in part due to a relatively sparse observation network. In this study we evaluate the impact of assimilating estimates of horizontal visibility derived from a novel network of web cameras in Alaska with the RTMA. Results suggest that the web camera-derived estimates of visibility can capture low visibility conditions and have the potential to improve the RTMA visibility analysis under conditions of low instrument flight rules and instrument flight rules.

DEGENERALIZING INSTRUMENT APPROACH MINIMA TO NON INSTRUMENT RUNWAYS: A CASE STUDY FOR PAYERNE AIRPORT IN SWITZERLAND

Instrument approaches to non- instrument runways were made possible by the new approach classification of ICAO. As a conservative solution, the procedure design guidelines by the national civil aviation authorities apply circling minima to those approaches to non-instrument runways. However, the classification as non-instrument runway is very binary. Often a small item causes a reduction from instrument to a non-instrument runway and the circling minima become thus very conservative. Here, two cases are shown, Payerne, a non-instrument runway, and Ouessant with an instrument runway, both equipped very differently but both serving Instrument Flight Rules (IFR) traffic. Solutions for Payerne and other similarly highly equipped non-instrument runways are proposed in order to be able to accommodate at least non-precision minima.

A Probability-Based Daytime Algorithm for Sea Fog Detection Using GOES-16 Imagery

Fog is a hazardous weather event that can endanger navigation, aviation, and transportation. While human has several limitations in detecting and forecasting offshore fog, satellite remote sensing offers cost-effective images. In this study, a probability-based daytime sea fog detection algorithm, applied to geostationary operational environmental satellite (GOES) 16 satellite data over the Grand Banks offshore Eastern Canada, is presented and compared with the National Oceanographic and Atmospheric Administration (NOAA)'s Low Instrument Flight Rules (LIFR) probability map. Initially, clear-sky and ice cloud classes were delineated in the GOES-16 image and then the remaining pixels were assigned a fog probability by conducting small droplet proxy, spatial homogeneity, and temperature difference tests. Moreover, a green band was linearly interpolated using the first three bands of GOES-16 images to generate pseudotrue color composites. The resulting maps were evaluated both during an extended sea fog event and using several statistical measures. The average detection probability for the observed advection fog events was 66% for the proposed method, while that for NOAA's LIFR map was 38%. Furthermore, by thresholding the generated maps at the probability of 60%, the false alarm rate, probability of detection, hit rate, and Hanssen–Kuiper skill score were 0.09, 0.77, 0.83, and 0.68, respectively. The proposed method is operationally being used in this region to detect and monitor sea fog, facilitating safe navigation and aviation. This is the first study that uses GOES-16 for daytime fog detection and discusses a satellite-based solution for fog modeling in Grand Banks, NL.

Overcoming Sovereignty for Space Traffic Management

The question of sovereignty, or authority over the space domain has created a barrier to development of space traffic management regimes, particularly those seeking to use air traffic control or air traffic management (ATM) as an operational model. States exercise control over sovereign airspace as the airspace over a state and its territorial waters is recognized as within its authority. States provide air traffic services over high seas airspace that is delegated to them by the Council of the International Civil Aviation Organization under the provisions of the Chicago Convention. This concept of air traffic management is built on a foundational understanding that a single authority is responsible for each defined volume of airspace.In the space domain, there is no specific delegation of volumes of space to specified authorities. The Outer Space treaty clearly reflects that no claim of sovereignty is to be made. Without the authority to exercise sovereign control over the domain, is space traffic management possible?Consider that space activities are launched from sovereign territory, transit through sovereign airspace, progress through high altitude/near space regions where sovereignty is ambiguous, and operate in orbits where no sovereignty exists; is too much emphasis placed on the sovereignty question? If we make a clear distinction between regulation and control, can we eliminate the sovereignty barrier? To apply the model of air traffic management to a space traffic management concept that is applicable from the on-orbit regime, down to the near space transition, to regulated airspace, a comprehensive understanding of the elements of ATM is needed to identify relevant tools that can be exported to STM. The concept of air traffic control over instrument flight rules (IFR) flights is less relevant to STM than other regulatory and advisory elements of ATM including flight services, traffic information services, and safety alerts. Similarly, dividing STM into its component parts allows for comparisons to elements of ATM that may provide operational models for the provision of a safety service that does not depend on sovereign authority or exclusive control over a volume of space. This paper will examine the legal, policy and technical barriers to the implementation of a space traffic management regime and specifically how the sovereignty barriers can be overcome to construct and implement a global safety service in space.

A Quality Assessment of the Real-Time Mesoscale Analysis (RTMA) for Aviation

Abstract Missing observations at airports can cause delays in commercial and general aviation in the United States owing to Federal Aviation Administration (FAA) safety regulations. The Environmental Modeling Center (EMC) has provided interpolated temperature data from the National Oceanic and Atmospheric Administration’s Real-Time Mesoscale Analysis (RTMA) at airport locations throughout the United States since 2015, with these data substituting for missing temperature observations and mitigating impacts on air travel. A quality assessment of the RTMA is performed to determine if the RTMA could be used in a similar fashion for other weather observations, such as 10-m wind, ceiling, and visibility. Retrospective, data-denial experiments are used to perform the quality assessment by withholding observations from FAA-specified airports. Outliers seen in the RTMA ceiling and visibility analyses during events meeting or exceeding instrument flight rules suggest the RTMA should not be substituted for missing ceiling and visibility observations at this time. The RTMA is a suitable replacement for missing temperature observations for a subset of airports throughout most of the CONUS and Alaska, but not at all stations. Likewise, the RTMA is a suitable substitute for missing surface pressure observations at a subset of airports, with notable exceptions in regions of complex terrain. The RTMA may also be a suitable substitute for missing wind speed observations, provided the wind speed is ≤15 kt (1 kt ≈ 0.51 m s−1). Overall, these results suggest the potential for RTMA to substitute for additional missing observations while highlighting priority areas of future work for improving the RTMA.

Critical Care Transport Time Differences Between Ground, Helicopter VFR, and Helicopter IFR Transports.

BACKGROUND: In helicopter critical care and emergency medical services (HEMS) transportation, organizations aim for efficiency of the dispatch process. Most HEMS organizations do not provide transport under instrument flight rules (IFR), due to equipment and training cost. Boston MedFlight (BMF) provides IFR HEMS transport. We set out to determine if response time of IFR transport was superior to ground transport.METHODS: A retrospective analysis of quality improvement data was performed. Data was collected by two observers sitting in the BMF control room in varying shifts. A process map of the dispatch process, from the dispatch call to the vehicle en route was developed. Critical points in the dispatch process were determined and a variety of time differences to determine the length of processes in the dispatch calculated. We compared median time differences between visual flight rules (VFR) flight and IFR flight, between IFR flight and ground transport, and between VFR and Ground for these points using a Mann-Whitney U-test.RESULTS: During the study collection period, 443 transports occurred, of which 109 transports happened while the observers were present: 37 ground, 57 VFR, and 15 IFR. Due to weather, six IFR transports were declined. The overall time from dispatch call to vehicle en route was significantly increased for IFR flights [median: 30 min:8 s (interquartile range 19:06-49:04)] over both VFR flights [11:36 (9:24-17:06); P vs. IFR: 0.001] and ground transports [9:39 (6:59-14.51); P vs. IFR: 0.001]. Most of this increase was accounted for by increases in the time from dispatch to crew acceptance, and from rotor start to vehicle en route.DISCUSSION: IFR conditions resulted in significantly increased dispatch times over both VFR flight and ground transport. The increase is likely a result of weather check, filing an IFR flight plan, and IFR release. Dispatch algorithms should be adjusted for this time delay of IFR transports.Kamine TH, Thomas L, Davis C, Cohen J. Critical care transport time differences between ground, helicopter VFR, and helicopter IFR transports. Aerosp Med Hum Perform. 2020; 91(2):98-101.

Present and Future of Air Navigation: PBN Operations and Supporting Technologies

The present work reviews the new concept of operation that will be soon implemented in SESAR and NextGen (January 2020) using new state-of-the-art technology mainly based on onboard avionics: data link equipment, broadcast and surveillance systems, and Global Navigation Satellite System (GNSS) area augmentation. One of the main improvements of Performance-Based Navigation (PBN) is the use of satellites and more precise and accurate onboard instruments than current standard avionics related to ground-based navigation aids (VOR, NDB, DME, etc.). Air navigation systems have been without mayor updates for nearly 40 years, when most Very High Frequency Omnidirectional Range (VOR) and Tactical Air Navigation (TACAN) systems were implemented worldwide in the civil and military fields, respectively. These standard navigation systems lack new required performance navigation and required big deal of maintenance, especially in redundant systems. Recently, the development of new and precise GNSS and communication systems has allowed their use on different scenarios: Instrumental Flight Rules (IFR) departures, initial and final approaches, etc. Additionally, in several international airports, Ground Based Augmentation System (GBAS) approaches have been already successfully tested and implemented. Related to GBAS, the Automatic Dependent Surveillance Broadcast (ADS-B) is a cooperative technology that enhances pilots and controllers’ situation awareness, since ADS-B broadcasts own and other aircraft position. Controller Pilot Data Link Communications (CPDLC) may be another key element of the PBN concept of operations (CONOPS), since it provides air–ground data communications for the air traffic control (ATC) service and the aircrew, reducing risks associated to human factor: poor speaking, radio congestion, message confusion, standardization, etc. The main goal of this review is to present the PBN concept and the potentially supporting Communication, Navigation and Surveillance (CNS) systems, in the context of the NextGen and SESAR Air Traffic Management (ATM) modernization programmes.

Models of the Reference Departure and Arrival IFR Procedures for the Purpose of Research in RPAS Integration in Controlled Airspace

Abstract The air operations in controlled airspace performed according to Instrument Flight Rules (IFR) are composed of three main flight phases, i.e. departure, cruise, arrival. Controlled airspace is divided into the terminal area and en-route airspace. The terminal area encloses the departure and arrival phases while the en-route airspace encloses the cruise phase. The IFR procedures are designed for manned aviation to ensure the safety of air operations. Development of the aviation concerns among others the increase in the number of unmanned aviation operations. Currently, on the European level, there is an on-going, long-term program of integration of the unmanned aviation in the uniform (non-segregated) airspace. This work concerns the research in the integration of the Remotely Piloted Aircraft Systems (RPAS) in the IFR procedures of the controlled airports. The objective was to build the reference models of Standard Instrument Departure and Arrival Procedures (SID and STAR). Basing on the procedure design guidelines the models of procedural nominal track, tolerance area, obstacle clearance area, climb or descend gradient, manoeuvres in SID and STAR were done. The guidelines describe the operational minima thus the statistics of existing procedures was done to select the suitable procedure parameters such as a number of navigational points, segments lengths, altitudes, climb or descent gradients. Reference models of SID include straight departure and turning departure procedures. Reference models of STAR include non-precision approach procedures according to used navigational aids, i.e. GNSS, VOR. The reference procedures were numerically implemented which will be used in the further works on RPAS integration problem by simulations of the RPAS ability to execute of the SID and STAR.

Systems Safety Risk Analysis of Fatal Night Helicopter Emergency Medical Service Accidents.

INTRODUCTION: In the United States, the proportion of Helicopter Emergency Medical Service (HEMS) fatal accidents remained unchanged despite an overall decreasing accident rate. Previous research showed night HEMS operations influenced fatal outcomes. Pilots with <6 yr of HEMS domain task experience (low-DTE) had a higher likelihood of a night operational accident in conditions associated with adverse weather. This study sought to determine whether a difference existed between day and night fatal accident rates and identify influences contributing to night fatal HEMS accidents. Any risk factors identified will be used for a risk analysis to inform future operational safety of the night visual flight rule (VFR) HEMS transport system.METHODS: Historical accident data and industry hours were obtained. Both pilot DTE groups (low and high) and mission VFR and instrument flight rule (IFR) capability were identified using data from 32 night VFR operational fatal HEMS accidents. Accidents were stratified by loss of control and controlled flight into terrain, pilot DTE, and flight rule capability. The effectiveness of both DTE groups and both flight rule capabilities were measured using system safety risk analysis techniques.RESULTS: Night fatal accident rates were statistically different from daytime. Low-DTE pilots and the VFR capability combination had the highest likelihood of night operational nonsurvivable accident.CONCLUSION: Low-DTE pilots and the VFR capability were the least effective mission combination to avoid hazardous conditions at night and maintain spatial orientation, respectively. The analysis identified measures to reduce likelihood of night fatal operational accidents.Aherne BB, Zhang C, Chen WS, Newman DG. Systems safety risk analysis of fatal night Helicopter Emergency Medical Service accidents. Aerosp Med Hum Perform. 2019; 90(4):396-404.