Supersonic flight over land will require pilots to understand and manage sonic boom noise in real-time. For humans to understand the complex relationships of shock wave propagation in the atmosphere and where it impacts terrain, a perspective display of this information is a natural extension of current efforts using synthetic vision displays. In previous research a NASA developed algorithm was used to calculate sonic boom prediction, Mach cut-off, and sound pressure levels for current and modified flights plans. The algorithm information was transformed into georeferenced objects, presented on navigation and guidance displays and integrated with synthetic vision. We conducted a usability demonstration with experienced pilots to assess their ability to use the display to determine whether the flight plan avoids the generation of a sonic boom in noise-sensitive areas, their ability to modify their flight plan to resolve impact issues, and reviewed the implementation of a real-time guidance capability. This paper provides an overview of the usability demonstration and discusses the additional capability of providing a pilot alerting mechanism and automated impact evaluations.
Synthetic vision systems are becoming common in the business jet community. The perspective display of terrain information provides a display of complex information in a visual manner that pilots are accustomed to. Research and flight testing is underway to allow low noise supersonic business jet operations. Widespread acceptance will require regulatory changes, the ability for pilots to predict, and manage where the generated sonic boom will impact people on the ground. A display of the sonic boom impact will be needed for preflight and inflight planning. This paper details the CONOPS, algorithm development, and human machine considerations of a synthetic vision display design incorporating a sonic boom carpet. Using a NASA developed algorithm, sonic boom prediction, Mach cut-off, and sound pressure levels are calculated for current and modified flights plans. The algorithm information is transformed into georeferenced objects, presented on navigation and guidance displays, where pilots can determine whether the current flightplan avoids the generation of sonic booms in noise-sensitive areas. If pilots maneuver away from the flightplan, a dynamically computed predicted boom carpet is presented in which the algorithm is fed an extrapolation of the current flightpath. The resulting depiction is a sonic boom footprint which changes location as the aircraft maneuvers. Using a certain lookahead time for the prediction, the pilot has the ability to shift the location where boom intensity will be at a maximum. Considerations of allowable sound levels for various locations on the ground are incorporated for comparison of the realtime and predicted sonic boom.
The research described in this paper explores the addition of conformally integrated traffic probes into an egocentric
Synthetic Vision (SV) Primary Flight Display (PFD). The underlying thought is that, although the traffic that is predicted
to cause a future loss of separation may not lie within the field of view of the display, the location where the loss of
separation is predicted to occur always will. Hence, rather than focusing on the depiction of traffic, which contributes to
level 2 Situation Awareness (SA), the concept pursues spatially integrated depiction of the airspace where a loss of
separation is predicted. This provides readily actionable conflict information, relieving pilots from the traffic position
and conflict estimation task and contributing to level 3 SA. The paper describes the integration of the data from the
traffic probe into an SV PFD. The advantages of the concept will be illustrated using several traffic conflict scenarios,
including an overtaking scenario involving unmanned aircraft. Given that unmanned aircraft may be markedly slower
than manned aircraft which operate within the same airspace, a spatially integrated depiction of airspace where a future
loss of separation is predicted, can help to preserve safety in classes of airspace that accommodate both manned and
unmanned aircraft. Additionally, examples are provided illustrating how traffic probes can support pilots in monitoring
the conformance of traffic to the priority rules of 14 CFR 91.113.
This paper addresses the design and implementation of a conceptual Enhanced/Synthetic Vision Primary Flight Display
format. The goal of this work is to explore the means to provide the operator of a UAV with an integrated view of the
constraints for the velocity vector, resulting in an explicit depiction of the margins/boundaries of the multi-dimensional
maneuver space. For non-time-critical situations, this is expected to provide support when the operator has the authority
to manually set avoidance maneuvers, or approve, veto or modify velocity vector changes proposed by the automation.
The integration of the upper bounds of the maneuver space, resulting from energy constraints, and the lower bounds,
resulting from terrain will be illustrated. Additionally, the application of a maneuver cost function will be discussed, for
identifying and prioritizing conflict avoidance options from an integrated multi-dimensional maneuver space, and
communicating those to the operator. Although the integrated avoidance functions have been developed with the UAV
application in mind, they have equal merit for manned aircraft. The need for specific GUI elements depends on the level
of authority of the system and the role of the operator/pilot, which may differ between manned and unmanned
applications.
For Unmanned Aerial Vehicles (UAVs), autonomous forms of autoland are being pursued that do not depend on special,
deployability restraining, ground-based equipment for the generation of the reference path to the runway. Typically,
these forms of autoland use runway location data from an onboard database to generate the reference path to the desired
location. Synthetic Vision (SV) technology provides the opportunity to use conformally integrated guidance reference
data to 'anchor' the goals of such an autoland system into the imagery of the nose-mounted camera. A potential use of
this is to support the operator in determining whether the vehicle is flying towards the right location in the real world,
e.g., the desired touchdown position on the runway. Standard conformally integrated symbology, representing e.g., the
future pathway and runway boundaries, supports conformance monitoring and detection of latent positioning errors.
Additional integration of landing performance criteria into the symbology supports assessment of the severity of these
errors, further aiding the operator in the decision whether the automated landing should be allowed to continue or not.
This paper presents the design and implementation of an SV overlay for UAV autoland procedures that is intended for
conformance and integrity monitoring during final approach. It provides preview of mode changes and decision points
and it supports the operator in assessing the integrity of the used guidance solution.
The guidance information that is available to the UAV operator typically suffers from limitations of data update rate and
system latency. Even when using a flight director command display, the manual control task is considerably more
difficult compared to piloting a manned aircraft. Results from earlier research into perspective guidance displays show
that these displays provide performance benefits and suggest a reduction of the negative effects of system latency. The
current study has shown that in case of limitations of data update rate and system latency the use of a conformal sensor
overlay showing a perspective presentation of the trajectory constraints is consistently superior to the flight director
command display. The superiority becomes more pronounced with an increase in data latency and a decrease in update
rate. The fact that the perspective pathway overlay as used in this study can be implemented on any graphics system that
is capable of rendering a set of 2-D vectors makes it a viable candidate for upgrades to current systems.
In the past fifteen years, several research programs have demonstrated potential advantages of synthetic vision
technology for manned aviation. More recently, some research programs have focused on integrating synthetic vision
technology into control stations for remotely controlled aircraft. The contribution of synthetic vision can be divided into
two categories. The depiction of the environment and all relevant constraints contributes to the pilot's situation
awareness, while the depiction of the planned path and its constraints allows the pilot to control or monitor the aircraft
with high precision. This paper starts with an overview of the potential opportunities provided by synthetic vision
technology. A distinction is made between the presentation domain and the function domain. In the presentation
domain, the benefits are obtained from making the invisible visible. In the function domain, benefits are obtained from
the possibility to integrate data from the synthetic vision system into other functions. The paper continues with a number
of examples of situation awareness support concepts which have been explored in the current research. After this, the
potential contribution of synthetic vision technology to the manual control task is discussed and it is indicated how these
potential advantages will be explored in the next research phase.
Several emerging technologies were recently demonstrated in a Boeing 737-900 as part of Boeing's Technology Demonstrator program. Among these technologies were two enhanced vision systems and a synthetic vision system, including synthetic displays to support surface operations. This project gained operational experience with enhanced and synthetic vision systems operating in a context that included Required Navigation Performance (RNP) terminal area operations, Global Navigation Satellite System (GNSS) approach and landing, and Integrated Area Navigation (IAN). The technologies were demonstrated to a broad mix of constituents involved in research, regulation, and acquisition in the transport category environment. This paper describes the systems demonstrated, the context in which they were used, and perceived benefits of integrating them in an operational environment. Lessons learned in the implementation of these technologies throughout the program are described and subjective data from participants are summarized.
KEYWORDS: 3D displays, Navigation systems, Databases, Data integration, Safety, Data conversion, Synthetic vision, Visualization, Sensors, Control systems
Perspective flightpath displays and the depiction of 3-D terrain are regarded as a potential means to increase safety. Although the technology to generate such presentations in real-time is available, other issues which are required for a safe introduction must still be resolved. This paper focuses on some of the major obstacles which are still present. It discusses several objections against perspective flightpath displays and shows why most of them are no longer justified. The potential for an increase in safety is related to navigation, guidance, and control task requirements, and potential implementations, ranging in complexity, to satisfy these requirements are discussed. This classification allows a gradual transition from today's 2-D symbolic displays to future spatial displays. The paper proposes an approach which supports an evolutionary introduction of 3-D navigation displays into the cockpit.
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