Into Instrument Meteorological Conditions Research Articles

VFR Into IMC Through the Lens of Behavioral Economics

Decision-making can be the difference between life and death in all types of aviation, but in general aviation (GA), where most of the flying is conducted as single-pilot operations, the decision-making of one individual becomes fundamentally important. It is critical to consider, first, why pilots make bad decisions that can ultimately lead to weather-related aviation accidents or incidents; and second, whether a better understanding of weather-related decision-making can inform regulations that will improve decision-making and consequently reduce the frequency of pilot-error accidents. Behavioral economics (BE) aims to better understand individual decision-making to model decision-making pathways. As individual decision-making is central to aviation safety, better modeling of decision-making pathways should be a central aim not just for pilots, but also for aviation regulators, such as the Civil Aviation Safety Authority (CASA) in Australia. While there has been little analysis of pilot decision-making using BE, we argue that BE, with its focus on predictive models of individual decision-making, provides a rich framework to understand pilot decision-making and inform more targeted regulation. This argument is in four parts. The first part identifies that there is an ongoing safety issue with visual flight rules (VFR) pilots flying into instrument meteorological conditions (IMC). The second part introduces some of the core concepts of BE, such as the rejection of perfect rationality and the reliance upon certain behavioral biases in decision-making. We argue that VFR into IMC is an appropriate context in which to apply BE as there is an identifiable measure of a pilot’s welfare and concerns around paternalism fall short when dealing with protecting the welfare of those likely to be impacted by a pilot’s decision-making, such as passengers and aircraft owners. The third part reviews the existing research applying behavioral models of decision-making in respect of VFR into IMC and identifies three behavioral biases that—among others—can lead to poor decision-making: (i) environmental literacy, (ii) overconfidence, and (iii) prospect theory. The final part briefly introduces some potential avenues for BE to inform regulatory reform, including better education of pilots and regulators in respect of the psychological factors to which pilots may fall victim, as well as more directed training for pilots to address the environmental literacy concerns identified in this part. We conclude that the regulatory environment should be reformulated to adequately account for predictable behavioral biases.

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.

Improving Weather Display Interpretation: A Training Solution

Visual flight rules (VFR) operations into instrument meteorological conditions (IMC), is one of the deadliest causes of weather-related accidents in the General Aviation (GA) community. Current weather training for GA pilots is inadequate. This paper describes the design and development of three weather training modules and provides research-based recommendations for the development of future training modules for aviation weather. Recommendations include incorporating simulation-based training, utilizing available materials, prioritizing accessibility, accounting for changing technology, maintaining high cognitive fidelity, and using a multidisciplinary team approach.

Helicopter Pilots Encountering Fog: An Analysis of 109 Accidents from 1992 to 2016

Helicopters have the ability to make maneuvers or precautionary off-airport landings to avoid flights into instrument meteorological conditions (IMC) such as fog. Flight accidents in which fog was encountered as well as inadvertent and intentional flights into fog were examined to understand their occurrence. A 25-year period in the United States using the National Transportation Safety Board online database was used to collect 109 accident reports of which 73 (67%) were fatal. Pilots flying intentionally into IMC were more likely to be a part of a fatal accident than those who did so inadvertently. Those pilots who were reported as being under pressure when encountering fog conditions were also more likely to be in an accident. The findings confirm a high prevalence and an added danger to intentional flights into IMC. In addition, decision-making under pressure when encountering IMC conditions is now linked to a higher proportion of fatalities, emphasizing that helicopter pilots should be made aware of these specific decision-making circumstances in their operations.

Correlates of Continued Visual Flight Rules (VFR) into Instrument Meteorological Conditions (IMC) General Aviation Accidents

Correlates of Continued Visual Flight Rules (VFR) into Instrument Meteorological Conditions (IMC) General Aviation Accidents

Characteristics of pilots who report deliberate versus inadvertent visual flight into Instrument Meteorological Conditions

Aircraft accidents and incidents associated with visual flight into instrument weather conditions continue to account for a significant proportion of fatalities involving general aviation aircraft. The aim of this study was to examine pilot recounts of flights involving inadvertent or deliberate flight into Instrument Meteorological Conditions (IMC). Of the 251 responses that were examined, 145 pilots indicated that they had entered IMC inadvertently during a visual flight, while 93 had done so deliberately. Amongst non-instrument-rated pilots, two cohorts were identified whereby pilots who deliberately entered instrument conditions tended to have experienced the conditions previously, possess a comparatively greater tolerance of risk, experienced less anxiety during the event recounted, and perceive the risks associated with the transition into instrument conditions as relatively lower than those pilots whose entry into instrument conditions was inadvertent. These results are interpreted as confirmation of the need to address the problem of visual flight into instrument conditions from a number of different perspectives, taking into account experience and individual differences in risk tolerance.

Pilot Error During Visual Flight Into Instrument Weather: An Experiment Using Advanced Simulation and Analysis Methods

This study details competing literature findings surrounding visual flight rules (VFR) flight into instrument meteorological conditions (IMC), and it utilizes advanced simulation to fulfill training inadequacies and bring clarity to the research. An experiment involving 16 visual-only pilots was conducted to simulate cross-country flight in marginal weather. Participants' abilities to aviate, navigate, communicate, and process weather information were measured and correlated with demographics and the pilots' abilities to adhere to visual flight regulations. 11 out of the 16 pilots committed violations, and the pilots' previous exposure to instrument weather made them better at collecting in-flight weather reports and obeying VFR regulations. Pilots that penetrated simulated IMC were found to be more reliant on cockpit automation such as autopilot and navigation equipment. Misuse of automation often lead pilots to become overwhelmed by IMC, and in severe cases, pilots displayed flight profiles characteristic of spatial disorientation and lost control of the aircraft or they wandered at dangerously low altitudes in zero visibility, putting them at risk for controlled flight into terrain. This study represents a validation of the advancement of weather simulation to improve flight training, practical examination, and investigation. Language: en

Performance of Helicopter Pilots During Inadvertent Flight Into Instrument Meteorological Conditions

Inadvertent flight into instrument meteorological conditions (IMC) is a major cause of general aviation accidents. However, performance of helicopter pilots during inadvertent IMC encounters has not been investigated. We developed objective methods to quantify helicopter pilot effort and performance and applied these to simulated flight into IMC. Results showed strong effects of visibility and weaker effects of altitude and airspeed. The analyses revealed important information regarding the relationships among visibility, altitude, airspeed, aircraft performance, and pilot effort. Short training sessions produced significant performance improvements. The methods developed for quantifying pilot effort and performance can be applied to myriad investigations of pilot performance.

Eye Tracking Analysis of the Effects of Experience and Training on Pilots' Ability to Identify Adverse Weather Conditions

Adverse weather remains one of the leading causes of fatal accidents in general aviation. A large portion of fatal weather accidents involve visual flight rules (VFR) pilots' continued flight into instrument meteorological conditions (IMC). This study aims to analyze the way experience and training affect pilots weather identification accuracy, response bias, and visual scanpaths. The study involved 60 participants divided into three experience groups: non-pilots, low-time pilots, and high-time pilots. Participants viewed a series of weather scenes and were asked to determine if the conditions allowed for VFR flight. Participants then completed WeatherWise, a cue-based training program, before viewing another group of weather images. While training failed to improve decision accuracy for any group, all groups showed a significant shift in bias towards not continuing flight after training. The eye tracking data showed many differences in visual scan behavior between experience groups and training conditions.

Eye Tracking Analysis of the Effects of Experience and Training on Pilots' Ability to Identify Adverse Weather Conditions

Adverse weather remains one of the leading causes of fatal accidents in general aviation. A large portion of fatal weather accidents involve visual flight rules (VFR) pilots' continued flight into instrument meteorological conditions (IMC). This study aims to analyze the way experience and training affect pilots weather identification accuracy, response bias, and visual scanpaths. The study involved 60 participants divided into three experience groups: non-pilots, low-time pilots, and high-time pilots. Participants viewed a series of weather scenes and were asked to determine if the conditions allowed for VFR flight. Participants then completed WeatherWise, a cue-based training program, before viewing another group of weather images. While training failed to improve decision accuracy for any group, all groups showed a significant shift in bias towards not continuing flight after training. The eye tracking data showed many differences in visual scan behavior between experience groups and training conditions.

Pilot Weather Assessment: Implications for Visual Flight Rules Flight Into Instrument Meteorological Conditions

Visual flight rules flight into instrument meteorological conditions (IMC) account for over 10% of the fatalities in general aviation. Evidence suggests that pilots' assessments of weather conditions are related to their decision to continue. This study investigated pilots' ability to assess ceiling and visibility in a flight simulator. Assessment accuracy did not differ between instrument- and non-instrument-rated pilots for ceiling accuracy, but visibility accuracy was better for non-instrument-rated pilots. The data indicated pilots allowed their estimates of ceiling and visibility to influence each other. That is, pilots tended to judge a ceiling to be higher than it actually was when it was paired with a high visibility. This interaction may play a significant role in pilots' decisions to continue into IMC.

Characteristics of alcohol-related fatal general aviation crashes

Background: The effects of alcohol on piloting performance have been studied extensively. Information describing alcohol-related aviation crashes, however, is scant. Methods: We developed a data system for fatally injured pilots in Maryland, New Mexico, and North Carolina by linking autopsy data from the state medical examiner offices and crash investigation reports from the National Transportation Safety Board. Alcohol-related crashes are defined as those in which the pilot had a blood alcohol concentration of 20 mg/dL or greater. Differences between alcohol- and non-alcohol-related crashes were assessed with regard to pilot characteristics, crash circumstances, and human factors. Results: The National Transportation Safety Board recorded 313 general aviation crashes fatal to the pilot in the three states between 1985 and 2000. Of these crashes, 255 (81%) were matched successfully with medical examiner records. Alcohol testing results were available for 233 of the fatally injured pilots. Of those tested for alcohol, 25 (11%) had blood alcohol concentrations ≥20 mg/dL (mean=75 ± 64 mg/dL). The majority of alcohol-related crashes (52%) occurred at night (7 p.m. to 6 a.m.), compared with 28% of other crashes ( P < 0.01). Alcohol-related crashes were significantly more likely than other crashes to have involved continued flight under visual flight rules (VFR) into instrument meteorological conditions (IMC) (32% versus 12%, P < 0.01), and flawed decisions (64% versus 41%, P = 0.03). Conclusions: Distinctive epidemiological patterns are exhibited in alcohol-related fatal general aviation crashes. Alcohol appears to play a particularly important role in crashes involving flight under VFR into IMC.

Symbology Development for General Aviation Synthetic Vision Primary Flight Displays for the Approach and Missed-Approach Modes of Flight

Spatial disorientation induced by inadvertent flight into instrument meteorological conditions (IMC) continues to be a leading cause of fatal accidents in general aviation. The Synthetic Vision Systems – General Aviation (SVS-GA) research element, an integral part of NASA's Aviation Safety and Security Program (AvSSP), is investigating a revolutionary display technology designed to mitigate low visibility events such as controlled flight into terrain (CFIT) and low-visibility loss of control (LVLOC). The integrated SVS Primary Flight Display (SVS-PFD) utilizes computer generated 3-dimensional imagery of the surrounding terrain augmented with flight path guidance symbology. This unique combination will provide GA pilots with an accurate representation of their environment and projection of their flight path, regardless of time of day or out-the-window (OTW) visibility. The initial Symbology Development for Head-Down Displays (SD-HDD) simulation experiment examined 16 display configurations on a centrally located high-resolution PFD installed in NASA's General Aviation Work Station (GAWS) flight simulator. The results of the experiment indicate that situation awareness (SA) can be enhanced without having a negative impact on task performance, by providing a general aviation pilot with an integrated SVS display to use when OTW visibility is obscured.

Visual Flight Rules Flight Into Instrument Meteorological Conditions: An Empirical Investigation of the Possible Causes

Pilots' decisions to continue or divert from a visual flight rules (VFR) flight into instrument meteorological conditions (IMC) were investigated using a dynamic simulation of a hypothetical cross-country flight. Differences in situation assessment, risk perception, and motivation between pilots who chose to continue or divert from a VFR flight into an IMC situation were examined. Results indicate that the simulation was successful in identifying pilots who would choose to either continue or divert and that differences existed between these two groups of pilots. Accuracy of visibility estimates, appraisal of one's own skill and judgment, and frequency of risk-taking behavior were most important in predicting whether a pilot would continue or divert the flight. Findings suggest that overconfidence in personal ability and inaccurate diagnoses of visibility conditions precipitate VFR flight into IMC. More research is needed, however, to identify effective methods for remedying these problems.

An Investigation of the Factors that Contribute to Pilots' Decisions to Continue Visual Flight Rules Flight into Adverse Weather

Pilots' decisions to continue or divert from a visual flight rules flight (VFR) into instrument meteorological conditions (IMC) were investigated using a dynamic simulation of a hypothetical cross-country flight. Issues related to decision-making were investigated. Specifically, differences in situation assessment, risk perception and motivation, between pilots who chose to continue or divert from a VFR flight into IMC situation were examined. Results indicate that the simulation was successful in identifying pilots who would choose to either continue or divert and that differences existed between these two groups of pilots. Accuracy of visibility estimates, appraisal of one's own skill and judgment and frequency of risk-taking behavior were most important in predicting whether a pilot would continue or divert from a VFR flight into IMC situation. Findings suggest that overconfidence in personal ability and inaccurate diagnoses of visibility conditions precipitate VFR flight into IMC.