Flight Display Research Articles

Visual cognition-based optimised design of primary flight displays in cockpits

Abstract The objective of this study was to investigate the effects of different cockpit primary flight display (PFD) interface designs on pilot cognitive efficiency and cognitive load. This study designed five optimised PFD interfaces and conducted interface cognition experiments to assess cognitive responses across six different PFD interface designs, including the original design. It compared various subjective and objective metrics across different interface designs and evaluated the impact of each design factor on cognitive task performance. The experimental results show that the PFD interface in the original interface design performs better under different flight symbol designs, and the interface with 50% increase in font size performs better among interface designs with different font sizes with relatively lower cognitive load. This study provides experimental support and optimization suggestions for the optimal design of cockpit PFD interface, which can help improve pilots’ perception and operational capabilities, and thus enhance task performance efficiency and flight safety. Future research can investigate the effects of various design factors on the cognitive effects of the interface to enhance the ongoing improvement and optimisation of interface design.

Future flight deck design: Developing an innovative touchscreen inceptor combined with the primary flight display

The touchscreen has the potential to optimize the space usage and efficiency of the flight deck. Currently, touchscreens can combine the input and output functions of different systems. However, it does not yet serve as an inceptor to replace the sidestick or control column for aircraft manoeuvres. This study aims to examine the potential of a touchscreen as a flight inceptor compared with a traditional sidestick and gamepad. This research recruited 72 participants who interacted with three inceptors for both an instrument landing with disturbance and without disturbance using the Future System Simulator. The findings demonstrated that pilot performance, system usability and pilots’ situation awareness of touchscreen inceptors were significantly inferior to those of traditional sidesticks and gamepads. Compared to the sidestick and gamepad, the touchscreen provided a poorer situation awareness with the highest supply and demand. In addition, the performance of all inceptors was significantly influenced by disturbance. There is still a long way to go for certification of a touchscreen as an inceptor on the future flight deck. This research showed that even though the touchscreen inceptor scored the lowest on both SUS and SART, the majority of pilots agreed that the touchscreen inceptor provided a better attentional supply in challenging disturbance circumstances, providing proof of concept for its possible inclusion in flight deck design. There is a potential that the emerging touchscreen as an inceptor may develop further along with human-system integration flight deck design.

Integration of Electronic Displays on Fixed Wing Transport Aircraft: A Vionics Certification

Electronic Flight Display System certification can present wide challenges in showing compliance with many existing regulatory requirements. This paper provides a guidance for manufacturers, system integrators and airworthiness authorities for the design, integration, and approval of electronic flight displays for fixed wing transport aircraft. Discussion on various existing standards available for aircraft electronic displays with their means of compliance at various stages of system certification has been presented in this paper. Detailed failure hazards associated with the failure of display functions are also provided in the paper.

Mechanical Device or Touchscreen Widget: The Effects of Input Device and Task Size on Data Entry on the Primary Flight Display

Due to their customizability, touchscreens continue to advance as a device of choice when designing aircraft cockpits. Previous studies investigated the effect of turbulence on human performance when using touchscreens, but few have evaluated its performance for realistic aviation-specific tasks. In this study, we compared four touchscreen widgets and three mechanical devices during realistic data input on a primary flight display (PFD). Twenty participants took part in the experiment at a constant level of vibration, while simultaneously completing a secondary tracking task. Results indicated that virtual keypads lead to faster completion time for medium to large changes while keeping error rates low. Rotary knobs were fastest for small changes. Virtual keypads also had lower workload and discomfort compared to rotary knobs and drag-based widgets. We found the completion time to be the most important factor in tracking task performance, which translated in higher precision for keypads. These findings suggest that virtual keypads represent an efficient and secure option for numerical data input at low-to-medium vibration.

Supplementing Haptic Feedback in Flight Envelope Protection Through Visual Display Indications

Haptic cues on the side stick are a promising method to reduce loss of control in-flight incidents. They can be intuitively interpreted and provide immediate support, leading to a shared control system. However, haptic interfaces are limited in providing information, and the reason for cues may not always be clear to pilots. This study presents the results of the conceptual development of visual display symbology that supports haptic feedback on the side stick in communicating flight envelope boundaries to pilots. Novel indications for the limits of airspeed, load factor, angle of attack, and angle of bank, which for the first time simultaneously indicate magnitude and direction of the haptic cues, were integrated in an Airbus primary flight display. The symbology was tested in a pilot-in-the-loop experiment with professional Airbus pilots () flying several approaches in alternate law with haptic feedback. Objective results do not show clear improvements, although the time spent outside the flight envelope is slightly reduced. Subjective results indicate a preference, however, for the new display and an increased understanding of the haptic feedback. Further research is recommended to improve the interface design, remove unused indications, and test a bank scenario using current operational bank limits.

A New Interface to Cope With Unreliable Airspeed Indications

Abstract. When unreliable airspeed events occur, the pilot flying (PF) is required to fly the aircraft using the thrust and the pitch parameters that are displayed in two distanced locations of the flight deck. The Sycopaero interface was designed to limit the PF’s workload by automatically displaying thrust and pitch values specific to aircraft configuration on the primary flight display. Participants performed a simulated flight scenario in which they lost airspeed information during take-off with and without the Sycopaero interface. Both behavioral and ocular results demonstrate that the Sycopaero interface significantly lowers the mental workload of PFs and improves their monitoring performance. Taken together, these results suggest that the Sycopaero interface may be a suitable solution to safely handle airspeed failures.

Low Cost Avionics System for Ultralight Aircraft

Abstract The article presents a low cost avionics system for ultralight aircraft and paraplanes. The system contains Attitude and Heading Reference System, Air Data Computer and Primary Flight Display. Communication between units is via Wi-Fi. In the article design description was presented, as well as laboratory tests results. They are promising and the system is ready for in flight testing.

Aviate, Navigate: Functional Visualizations of Asymmetric Flight Envelope Limits

Current aircraft flight deck interfaces do not provide information on how a performance-altering failure constrains an aircraft’s flight envelope. As a result, it is difficult for flight crews to plan maneuvers in order to reach navigation targets. This study presents the results of the conceptual development of constraint-based interface symbology that aims to address this issue. The proposed symbology is designed to integrate with both the primary flight display and navigation display. A small-scale, pilot-in-the-loop experiment () was conducted to assess the effectiveness of the used symbology in terms of flight performance and pilot usability. A simplified dynamic model with an asymmetric flight envelope was used to purposefully manipulate various levels of damage severity and corresponding flight envelopes. Results show that although the modifications to the primary flight display generally did not show statistically significant improvements, presenting flight envelope constraints as a reachable navigation envelope on the navigation display generally did do so for severe failures. The visualized envelope occasionally resulted in improved tactical control decisions at reduced workload levels. A future study involving a lager sample size and increased simulation realism should substantiate the discovered results.

Application of in-house software to improve the design process of multifunctional aircraft indicators and control panels

The process of frame development for Multipurpose Control and Display Unit (MCDU), Multi-Function Display (MFD), and Primary Flight Display (PFD) involves a significant documentation effort and must produce consistent interface at the early design stages. We developed a formal description of the interface, including the interaction vocabulary, as well as custom software to simplify these tasks and improve the overall design quality. The software builds a model of the human-machine interface and uses it to automatically generate frame specification/documentation. This methodology and the software are currently used in several commercial projects.

Mitigation of Biodynamic Feedthrough for Touchscreens on the Flight Deck

ABSTRACT Biodynamic feedthrough (BDFT) is a key issue for touchscreen operations on the future flight deck, as cockpit accelerations due to turbulence leave pilots vulnerable to erroneous touches that disrupt task performance. This research focuses on the implementation of a software-based cancellation approach to mitigate the adverse effects of BDFT in touchscreen dragging tasks. A flight-simulator experiment with 18 participants was performed to estimate models of BDFT dynamics for horizontal and vertical touch-inputs on a primary flight display. The averaged BDFT models were used to cancel BDFT in the same continuous dragging task used for model identification and a discrete point-to-point dragging task. While for the continuous task the cancellation enabled 63% mitigation in BDFT, the same cancellation was ineffective for the discrete task, due to reduced BDFT susceptibility. Overall, the results show that while model-based BDFT cancellation can be highly effective, a key technical challenge will be ensuring it is sufficiently task-adaptive.

Testing cockpit display systems of aircraft using a model-based approach

Avionics are highly critical systems that require extensive testing to comply with international safety standards. Cockpit display systems (CDS) are a mandatory part of modern cockpits of both manned and unmanned aircraft. The information from various avionics components is displayed on CDS using a variety of flight instruments. An important part of testing avionics systems is to evaluate whether the displayed information on the CDS is correct or not. A common industrial practice is to manually test CDS, which is time-consuming, labor-intensive, and error-prone. In this paper, we propose a model-based approach to automate the CDS testing of aircraft. The proposed approach tests the CDS at two levels: (i) at the system level to verify that the CDS are working correctly and (ii) at system integration level of CDS when these are integrated with various avionics components. As a part of our approach, we develop a UML profile to model various elements of the CDS. The models are then used to support the automated testing process. We evaluate our approach on two industrial case studies, the first case study represents a primary flight display (PFD) of an aircraft and the second one is the CDS of the ground control station (GCS-CDS) of an unmanned aerial vehicle. The evaluation results show that three potential faults are identified in the PFD and four major faults are found in the GCS-CDS.

High Speed Visualization in the JetOS Aviation Operating System Using Hardware Acceleration

The paper discusses details of the pilot display visualization that uses the hardware acceleration capabilities of the Vivante graphics processor in the JetOS aviation operating system. Previously the OpenGL Safety Critical library was implemented without hardware acceleration. This was done in such a way because software library is easier to certify in accordance with the avionics requirements. But usage of the software OpenGL does not provide acceptable visualization speed for modern Flight Display and 3D relief applications. So more complex visualization approach utilized the GPU acceleration capabilities was elaborated. Although the OpenGL library was implemented for a specific GPU and took into account its specificity, the described approach to adapt the MESA open source library can be used for other GPUs. An effective algorithm for multi-window visualization using the implemented library with hardware acceleration is present. The described approach allows you to achieve the visualization speed acceptable for the pilot display of the aircraft.

Augmented Reality for Immersive and Tactile Flight Simulation

Flight simulators based on wrap-around displays provide an immersive experience for pilot training, but not only are they expensive and bulky, they typically only simulate a single aircraft configuration. Virtual reality (VR) is an interesting alternative, providing an immersive experience with lower cost and space requirements, as well as the ability to simulate arbitrary aircraft. Unfortunately, current VR systems do not provide natural tactile interaction with instruments and avionics in the cockpit environment. This article explores augmented reality (AR) as an alternative to VR and wrap-around display flight simulators, delivering an immersive experience for pilot training and tactile interaction with aircraft controls. The concept is demonstrated through a basic general aviation simulator setup, showing that a relatively low-cost personal computer and graphics processing unit can provide AR simulations at useful frame rates.

Pilots' Visual Scanning Behaviors During an Instrument Landing System Approach.

BACKGROUND: Since eye movement can provide a reliable index of the attention allocation, which can assist in understanding pilots' cognitive state, this study investigated the effect of pilots' experience and the autopilot mode on their attention allocation on the Primary Flight Display (PFD) and Multi-Function Display (MFD) during an approach task.METHODS: There were 16 pilots who were classified into two levels of aviation expertise depending on the flight hours, and required to fly an Instrument Landing System approach. Their visual scanning behaviors were recorded through an eye tracker and analyzed based on fixation number and dwell time.RESULTS: The results revealed that the pilot experience level, instrument panel and autopilot mode all had significant impact on the fixation time ratio and dwell time. The pilots fixated most often on the PFD and had shorter dwell time. Furthermore, they had a lower fixation number and shorter dwell time on the PFD and MFD when the autopilot was off that they should allocate visual resources to the others (e.g., out-of-the-window) and obtain more information to maintain overall situation awareness under higher time pressure. Compared to pilots with more expertise, pilots with less expertise had an increased fixation number and decreased dwell time on the airspeed after turning off the autopilot.DISCUSSION: The present study indicated that the pilots had different visual scanning modes according to the flight mode and their experience. We expect that pilots' visual scanning behaviors during tasks will help the training and the design of the human-machine interaction.Lu Y, Zheng Y, Wang Z, Fu S. Pilots' visual scanning behaviors during an instrument landing system approach. Aerosp Med Hum Perform. 2020; 91(6):511-517.

Augmented visualization cues on primary flight display facilitating pilot's monitoring performance

• The incompatible human-computer interaction in the flight deck can lead to accident/incident. • Flight deck designs have to provide higher level of situation awareness by instinctively matching pilot's cognitive processes. • Salient visual cues can reduce pilot's cognitive effort to eliminating the requirements of text-reading on the interface displays. • The key concept behind augmented design is to merge the flight mode annunciator with raw flight data in the cockpit. • Augmented visualization cues can facilitate pilots identifying the flight status quicker and more accurate compared with traditional design. There have been many aviation accidents and incidents related to mode confusion on the flight deck. The aim of this research is to evaluate human-computer interactions on a newly designed augmented visualization Primary Flight Display (PFD) compared with the traditional design of PFD. Based on statistical analysis of 20 participants interaction with the system, there are significant differences on pilots' pupil dilation, fixation duration, fixation counts and mental demand between the traditional PFD design and augmented PFD. The results demonstrated that augmented visualisation PFD, which uses a green border around the “raw data” of airspeed, altitude or heading indications to highlight activated mode changes, can significantly enhance pilots' situation awareness and decrease perceived workload. Pilots can identify the status of flight modes more easily, rapidly and accurately compared to the traditional PFD, thus shortening the response time on cognitive information processing. This could also be the reason why fixation durations on augmented PFDs were significantly shorter than traditional PFDs. The augmented visualization in the flight deck improves pilots' situation awareness as indicated by increased fixation counts related to attention distribution. Simply highlighting the parameters on the PFD with a green border in association with relevant flight mode changes will greatly reduce pilots' perceived workload and increase situation awareness. Flight deck design must focus on methods to provide pilots with enhanced situation awareness, thus decreasing cognitive processing requirements by providing intuitive understanding in time limited situations.

A Comparative Study Installation Arrangement of Primary Flight Display (PFD) in the Flight Deck’s Regional Passenger Transport Aircraft

The Flight Deck or cockpit is designed to support the prosecution of aircraft mission. For aircraft with commercial purpose such as passenger transport aircraft, there must be good “fit” between the human, the machine which composed of various aircraft system and the aircraft mission; and these are what the Flight Deck design process needs to ensure but not limited to display design, aircraft control, automation, HCI on the Flight Deck and pilot’s view to outside through cockpit windows namely external vision. The external vision of cockpit windows must satisfy regulatory requirements which intended to ensure that the view is adequate for pilots to operate the aircraft safely and gives them a reasonable opportunity to see and avoid other aircraft that pose a collision threat.Concurrently during critical periods of flight, it is important that the flight crew access information in front of his view with minimal head rotation. Cockpit-Displays with critical flight information should then be located to these locations. Compromising both external vision and internal vision as Pilot’s visibility should be attained.

Spatial distribution of undulating flight displays of territorial Golden Eagles Aquila chrysaetos in Lewis, Scotland

ABSTRACTCapsule: The undulating display flight of Golden Eagles Aquila chrysaetos has a territorial function on current consensus: we found that displays could occur at any location within a home range of territorial birds and were not more frequent at the territorial limits (as documented by a previous study) or around the nest site.Aims: To test the null hypothesis that display activity does not spatially differ within the home range of territorial Golden Eagles.Methods: We used 1488 h of observations of Golden Eagles between April 2003 and October 2004 (excluding November through January inclusive) on the Isle of Lewis, northwest Scotland involving primarily four territories. Territorial boundaries and nest sites were determined by the behaviour of the focal territorial birds. All flight activity was cast into three spatial categories (near-boundary, near-nest and elsewhere) and the relative occurrence of displays was referenced by overall flight activity recorded in these spatial categories.Results: We failed to reject the null hypothesis. Prior findings of greater display rate at territory limits were not confirmed. Territorial Golden Eagles apparently displayed wherever they happened to be in their home range. There was no difference in display frequency between successful and failed breeding pairs and, within pairs, between successful and failed breeding seasons. Monthly changes in display activity did not differ from monthly changes in the presence of ‘intruding’ sub-adults. A peak in non-territorial bird activity in August and September was not reflected by a peak in display, however, we could not distinguish recently fledged ‘non-threatening’ birds in this period.Conclusions: Undulating flight displays of Golden Eagles focused neither on territory boundaries nor the nest. Displays may be spontaneous or occur in response to the detection of potential trespassers or neighbours, however, we could not rule out any role of pair-bonding.

Pilots' Fixation Patterns During Taxiing and the Effects of Visibility.

INTRODUCTION: Visual performance is important for safe and accurate taxiing operations. Visibility is associated with navigation errors during taxiing. The main objective of the present study was to investigate the effects of visibility on pilots' fixation patterns during taxiing. The interaction between visibility and flight experience was also examined.METHODS: Both experienced and less experienced pilots participated in the study. They were instructed to perform simulated taxiing tasks in two visibility conditions: clear day vs. low visibility. A mixed-model analysis of variance was performed to determine the main and interaction effects of 'visibility' and 'flight experience' on fixation data in each area of interest (AOI).RESULTS: The results showed that experienced pilots' fixation counts reduced on the electronic centralized aircraft monitoring (ECAM) area, but increased out the middle view (OTWM) and right view out of the window (OTWR) in low visibility than in clear day, while fixation counts among less experienced pilots increased on the primary flight display (PFD) and ECAM areas, but did not change significantly OTWM and OTWR in low visibility. Fixation duration increased by 59.8%, 9.8%, and 7.9% in ECAM, OTWL, and OTWR, respectively, in low visibility than in clear day.CONCLUSIONS: The findings suggest that pilots pay more attention and have higher perceptual load in the low visibility condition to maintain taxiing accuracy, and more experienced pilots make more visual efforts to extract information from AOIs outside the cockpit in the low visibility condition. These findings provide practical implications for safe and accurate taxiing operations.Zhang X, Qu X, Xue H, Liu J. Pilots' fixation patterns during taxiing and the effects of visibility. Aerosp Med Hum Perform. 2019; 90(6):546-552.

Evaluation of Aircrew Low-Intensity Threat Laser Eye Protection

Prototype low-intensity threat laser eye protection (LIT-LEP) spectacles were evaluated for US Coast Guard (USCG) cockpits and night vision goggle compatibility. The impetus for interest in aviation LIT-LEP is driven in part by the fact that easily accessible 0.5-2.0 W high-power laser pointers exceed safety standards for direct on-axis viewing. A repeated-measures experimental design was used to assess LIT-LEP performance relative to a no-LEP control for the following tasks: Near- and far contrast acuity, night vision goggle far-contrast acuity, emissive and non-emissive light source color-vision screening, and USCG multifunctional display color symbol discrimination reaction time and accuracy. Near- and far-contrast acuity results demonstrated good LIT-LEP performance for typical in- and out-of-cockpit lighting conditions. Night vision goggle performance suffered marginally at only one contrast level (85%; 20/30 acuity line). Color vision test results showed good color balance in that S-, M-, and L-cone performance did not demonstrate a clinical diagnostic color defect for emissive or non-emissive light sources when wearing LIT-LEP. Color symbol discrimination reaction-time-task results based on inverse efficiency scores revealed that some non-primary flight display colors exhibited a combination of slower speed and decreased accuracy. The findings will contribute to an acquisition decision as well as guide future LEP designs.

Design of a Primary Flight Display to Avoid Decelerating Below the Minimum Safe Operating Speed

Abstract. Analysis of recent airliner accidents and incidents identified a class of events in which structurally, mechanically, and electronically sound aircraft decelerated through the minimum safe operating speed for the phase of flight to the stick-shaker activation speed. Despite the differences in the sequences of events, a subset of the incidents and accidents had one thing in common – the automation was no longer actively controlling to the airspeed target. This article describes the accident scenarios and design of a modification to the airspeed tape on the primary flight display to explicitly annunciate the absence of active speed control. An experiment to evaluate the efficacy of the enhanced airspeed tape showed faster pilot response time but no differences in correct pilot response.