Aircraft Position Information Research Articles

Safety Assessment for Full Flight between Beidou Radio Determination Satellite Service Airborne Equipment and 5G System

The Beidou Radio Determination Satellite Service (RDSS) is an advantageous service of the Beidou system. However, due to the weak landing power of Beidou RDSS signals and an operating frequency close to the 5G frequency, the system is vulnerable to interference from ground signals. In this paper, from the perspective of civil aviation safety, different evaluation indicators are used for the takeoff and cruise phases, respectively, to study the impact caused by adjacent frequency interference on airborne Beidou RDSS equipment. In the takeoff phase, accurate aircraft position information is obtained by processing real trajectory files. Deterministic analysis methods are used to determine the safety distance for the coexistence of the two systems. During the cruise phase, ground-based 5G base stations have less influence on the airborne RDSS receiver due to the high flight altitude, so the main consideration is electromagnetic compatibility between the airborne Beidou RDSS system and the 5G ATG system. By establishing a Boeing 737–800 simulation model, the antenna isolation degree is used as the evaluation index, and a reasonable antenna layout is given according to the evaluation results. In this study, the theoretical simulation and real flight data are combined to summarise the exact range of adjacent frequency influence during the takeoff phase and a reasonable antenna layout during the cruise phase.

Verification of influence of the solar flare from September 2017 to ADS-B NAC parameter

This paper dissertates about the influence of space weather event from September 2017 on parameters NAC and NIC in ADS-B messages. Space weather have potential to influence GNSS navigation. Especially in the aviation, where we depend on th GNSS more. Therefore we examined the influence of solar flares on the aviation navigation system of commercial aircraft. We used data broadcasted by ADS-B system during the most severe space weather event. Parameters NAC and NIC describe the level of reliability of the aircraft position information based on the GNSS. Therefore, they might be partially used as sensors of any irregularities in GNSS signal. We focus on these parameters during one of the most severe solar flare in recent years to establish if there is any observable influence of the space weather on these parameters. We were able to prove that even during this severe flare that there was no degradation in the availability of the GNSS.

Flexible and extendable advance satellite tracking system

Aircraft tracking via satellite uses four dimensional aircraft position information to enhance flight safety by recording, scrutinizing and visualizing the information generated by an Airborne Tracking Unit (ATU) fitted onboard of aircraft flying from one point to another. It is an important device for aircraft operator to ensure its operational safety. Starfish Tracker SF3100-1 aircraft tracking unit can be used in aircraft satellite tracking applications. Research collaboration between Worldgate Technologies (WGT), Universiti Pertahanan Nasional Malaysia (UPNM) and Universiti Putra Malaysia (UPM) has developed the ATU originally from land base to airborne vehicles tracking, hence it provides multitudes of civil and military applications. The ATU is a unique device that enables multi-tasking application such as Air Combat Manoeuvring Instrumentation (ACMI), Network Centric Warfare and Flight Data Monitoring systems. In this paper, system characteristics and its applications are presented with the potential applications for Flight Data Monitoring system.

Analysis of surveillance position error for airfield detection

Purpose The surveillance equipment is one of the most important parts for current air traffic control systems. It provides aircraft position and other relevant information including flight parameters. However, the existing surveillance equipment has certain position errors between true and detected positions. Operators must understand and account for the characteristics on magnitude and frequency of the position errors in the surveillance systems because these errors can influence the safety of aircraft operation. This study aims to develop the simulation model for analysis of these surveillance position errors to improve the safety of aircrafts in airports. Design/methodology/approach This study investigates the characterization of the position errors observed in airport surface detection equipment of an airport ground surveillance system and proposes a practical method to numerically reproduce the characteristics of the errors. Findings The proposed approach represents position errors more accurately than an alternative simple approach. This study also discusses the application of the computational results in a microscopic simulation modeling environment. Practical implications The surveillance error is analyzed from the radar trajectory data, and a random generator is configured to implement these data. These data are used in the air transportation simulation through an application programing interface, which can be applied to the aircraft trajectory data in the simulation. Subsequently, additionally built environment data are used in the actual simulation to obtain the results from the simulation engine. Originality/value The presented surveillance error analysis and simulation with its implementation plan are expected to be useful for air transportation safety simulations.

Estimation of Aircraft Operations at Airports Using Mode-C Signal Strength Information

An understanding of aircraft operations counts at airports is important due to the use of that information in the allocation of the Federal Airport Improvement Program funds. Operations at airports lacking full-time personnel are typically sampled over time. The sample sizes are generally small, due to the inherent difficulty and expense of deploying acoustic or pneumatic counting devices for extended periods of time, leading to inaccuracies in the estimation of long-term totals. A means of counting operations using Mode S extended squitter (ES) aircraft transponder data received with a 1090-MHz software-defined radio (SDR) system has been developed by the authors. A limitation of this approach, however, is the relatively small ratio of Mode S ES signals to Mode S short squit and Mode C signals, which do not contain aircraft position information. This article presents a method for estimating distance information from the latter two types of transponder signals, enabling them to be used by the SDR-based device, along with Mode S ES signals, in the operations counting process. The distance estimation method described here is based on an adaptive Kalman filter incorporating parameter optimization using known distance information from Mode S ES signals and results in an average error of 0.83 nm in measurements within a 5-nm radius of the receiver. This level of uncertainty enables the use of Mode S short squit and Mode C signals to count aircraft operations at airports without the additional overhead of multilateration.

Development of aircraft path planning scheme through automatic dependent surveillance broadcast

The intelligent flight task algorithm for aircraft is investigated to effectively determine and search the best flight routes under complicated conditions, where the conditions include the complicated topography and threats from other flights in the route airspace. The threat is detected by automatic dependent surveillance broadcast (ADS-B), which provides continual broadcast of aircraft position, identity, velocity and other information through unencrypted data links to generate a precise air picture for air traffic management. The proposed method comprises safety distance and path planning by pulse coupled neural networks. The safety distance is regarded as a pre-processing procedure for searching safety path. And the pulse coupled neural network is adopted to provide a smooth flight route for aircraft. The global optimal flight route is acquired through wave propagation by pulse coupled neural networks. The result of simulation demonstrated that the proposed method has the ability to provide the best flight routes efficiently for aircraft.

Development of aircraft path planning scheme through automatic dependent surveillance broadcast

The intelligent flight task algorithm for aircraft is investigated to effectively determine and search the best flight routes under complicated conditions, where the conditions include the complicated topography and threats from other flights in the route airspace. The threat is detected by automatic dependent surveillance broadcast (ADS-B), which provides continual broadcast of aircraft position, identity, velocity and other information through unencrypted data links to generate a precise air picture for air traffic management. The proposed method comprises safety distance and path planning by pulse coupled neural networks. The safety distance is regarded as a pre-processing procedure for searching safety path. And the pulse coupled neural network is adopted to provide a smooth flight route for aircraft. The global optimal flight route is acquired through wave propagation by pulse coupled neural networks. The result of simulation demonstrated that the proposed method has the ability to provide the best flight routes efficiently for aircraft.

Multiplicative Error State Kalman Filter vs Nonlinear Complimentary Filter for a High Performance Aircraft Attitude Estimation

<p>Modern control law designs increasingly use aircraft attitude information to improve aircraft manoeuverability. Attitude information allows for gravity term compensations in the longitudinal as well as lateral directional control laws of a typical fighter aircraft. Methodologies and comparisons of multiplicative error state Kalman filter (MEKF) and nonlinear complimentary filter for estimation of attitudes of a high performance aircraft using its onboard autonomous sensors is presented. Shows a problem in pitch angle estimation beyond ± 80 deg in the MEKF and a solution is proposed for the same for the first time. Also presents novel aiding sensor modelling for the implementation of attitude heading reference system for this class of aircraft for the first time. The filter formulations are evaluated using full range manuoevering real flight test data.</p>

Attitude estimator for spinning aircraft using earth infrared radiation field

The continuous improvement in diversification, new-type orientation and low cost of navigation control system, the accurate measurement of the spinning aircraft flight attitude parameters has becomes a more and more urgent task. In view of the above problems, a novel attitude estimator for the spinning aircraft is proposed by using earth infrared radiation field. The attitude estimation system possesses several key advantages over the current designs in low cost, no need of moving parts, and being free from reliance on GPS or other state feedback. Firstly, the mechanism of earth infrared radiation field is described in detail, and an 8-14 m atmospheric window is selected as the study object. The land surface infrared radiation is calculated by the land surface temperature and emissivity. The sky infrared radiation is calculated through layered atmosphere by combing with the sky emissivity and infrared atmospheric transmittance. According to the calculations of land surface infrared radiation and sky infrared radiation, the mathematical model of earth infrared radiation field is established by combining with propagation law of infrared radiation in the atmosphere. Then the measurement model of thermopile sensors is derived, after analyzing the motion feature of spinning aircraft during the flight. The thermopile sensors convert the observed infrared radiation into an electrical signal well suited for onboard data acquisition. To explore the inner link between the thermopile sensor output and the spinning aircraft attitude information, the characteristics of the sensor output under different attitude angles and fields of view are studied. When the thermopile sensor characteristics are included, the fully developed model can be used to generate accurate sensor output as a function of attitude angle. Finally, the installation of the thermopile sensors on the spinning aircraft is designed, and the measurement model of onboard thermopile sensor is established. In order to improve the accuracy of attitude measurement, an extended Kalman filter is developed, which enables the estimating of real-time attitude angles and roll rate by using solely three-axis thermopile sensors as feedback. The result indicates that by using this high accurate algorithm, the pitch angle estimation error is within 0.02, the roll angle estimation error is within 0.1 and the roll rate estimation error is within 1 rad/s. The detection system is simple and practical, works stably, and can meet the requirements for spinning projectile attitude measurement. The attitude estimation system will provide a new method and theory for further developing the spinning aircraft state detection.

Evaluation of a novel attitude estimation algorithm for a high performance fighter aircraft

This paper discusses the evaluation of a novel attitude estimation algorithm (Kamali et al. (2013)) for a high performance fighter aircraft. This algorithm employs a new modelling approach in the Extended Kalman Filtering (EKF) framework to estimate aircraft attitude information without using forward acceleration sensor, Global Positioning System (GPS) sensors or magnetometer. Evaluation of the algorithm is conducted using flight data from a high performance fighter aircraft and using flight simulation data. Estimation results during various manoeuvres such as full rolls, inverted loops, split-S manoeuvres, steep climbs, and dives, are studied. Effect of different wind perturbations (gust, shear, turbulence, etc.), on estimation results, is also studied. Results using flight data are compared with those obtained from a GPS-assisted Inertial Navigation System (INS), whereas for results using simulation data, the simulation itself provides true values. Conclusions are drawn for the performance of the algorithm based on simulation and flight data.

Statistical Regular Pavings to Analyze Massive Data of Aircraft Trajectories

A variety of tasks conducted by aviation system decision makers and researchers requires analyzing aircraft trajectory data. Datasets containing high-frequency aircraft position information collected over large geographic areas and long periods of time are too large to store in the primary memory of personal computers. This paper introduces the use of statistical regular pavings as data structures capable of summarizing very large aircraft trajectory datasets. Recursively computable statistics can be stored for variable-sized regions of airspace. The regions themselves can be created automatically to reflect the varying density of aircraft observations, dedicating morecomputationalresourcesandprovidingmoredetailedinformation inareaswithmoreairtraffic.Inparticular, statistical regular pavings are able to very quickly aggregate or separate data with different characteristics so that data describing individual aircraft or collected using different technologies (reflecting different levels of precision) can be stored separately, and yet also very quickly combined using standard arithmetic operations.

Security analysis of the ADS-B implementation in the next generation air transportation system

The US Federal Aviation Administration’s Next Generation (NextGen) upgrade proposes a fundamental transformation that is intended to increase the capacity and safety of the air transportation system. A key component of the upgrade is the Automatic Dependent Surveillance Broadcast (ADS-B) system. ADS-B provides continual broadcast of aircraft position, identity, velocity and other information over unencrypted data links to generate a precise air picture for air traffic management. The Federal Aviation Administration claims that operational requirements necessitate the use of unencrypted data links and maintains that there is a low likelihood of malicious exploitation. This paper analyzes the security vulnerabilities associated with the ADS-B implementation. It describes a taxonomy of attacks and examines the potential impact that the attacks may have on air transportation operations. The taxonomy helps provide a comprehensive understanding of the threats associated with the ADS-B implementation, thereby supporting risk analysis and risk management efforts. The paper also provides recommendations that could enhance security if integrated into the ADS-B implementation plan.

Graceful Degradation of Air Traffic Operations: Airspace Sensitivity to Degraded Surveillance Systems

The introduction of new technologies and concepts of operation in the air transportation system is not possible unless they can be proven not to adversely affect the system operation under not only nominal but also degraded conditions. In extreme scenarios, degraded operations due to partial or complete technological failures should never endanger system safety. Many past system evolutions, whether ground-based or airborne, have been based on trial and error, and system safety was addressed only after a specific event yielded dramatic or near-dramatic consequences. Future system evolutions, however, must leverage available computation, prior knowledge, and abstract reasoning to anticipate all possible system degradations and prove that such degradations are graceful and safe. This paper is concerned with the graceful degradation of high-density structured arrival traffic against partial or complete surveillance failures. It is shown that for equal performance requirements, some traffic configurations might be easier to handle than others, thereby offering a quantitative perspective on these traffic configurations' ability to ldquogracefully degrade.rdquo To support our work, we also introduce a new conflict resolution algorithm aimed at solving conflicts involving many aircraft when aircraft position information is in the process of degrading.

Flying by Ear: Blind Flight with a Music-Based Artificial Horizon

Two experiments were conducted in actual flight operations to evaluate an audio artificial horizon display that imposed aircraft attitude information on pilot-selected music. The first experiment examined a pilot's ability to identify, with vision obscured, a change in aircraft roll or pitch, with and without the audio artificial horizon display. The results suggest that the audio horizon display improves the accuracy of attitude identification overall, but differentially affects response time across conditions. In the second experiment, subject pilots performed recoveries from displaced aircraft attitudes using either standard visual instruments, or, with vision obscured, the audio artificial horizon display. The results suggest that subjects were able to maneuver the aircraft to within its safety envelope. Overall, pilots were able to benefit from the display, suggesting that such a display could help to improve overall safety in general aviation.

Growth and Operating Patterns of Regional Jets in the United States

Data concerning the growth and utilization of regional jets between 1998 and 2003 are presented and analyzed. During this period, daily regional jet operations increased by 356%. These additional flights were primarily used to enter new midrange markets that were previously too far to serve efficiently with a turboprop and too small to warrant a traditional jet. Analysis of aircraft situational display to industry operational data also shows an increase in the stage length of regional jet flights; for example, at Dallas‐Fort Worth, the regional jet catchment basin increased from 299 n mile to 868 n mile. To better understand the reasons for the rapid growth of regional jets, an analysis of the economics of regional flight was performed. This analysis shows that airlines benefit from regional jets primarily because of the fee-per-departure payment structure and their current utilization patterns. HE number of regional jets in the national airspace system (NAS) has grown significantly over the past 10 years. Regional jets are small, 30‐100 seat aircraft capable of flying up to 1000 n mile and have been growing in number at a nearly exponential rate since 1994 (Ref. 1). This increase represents a major change in the composition of the national fleet and may affect the efficiency of the air traffic control system, as well as the dynamics of the airline industry. This paper examines the evolution of regional jet utilization to better understand their growth and operating patterns, as well as possible future trends. The goal just outlined was reached in two steps. The first was to analyze flight track data and develop methods to visualize and quantify any changes in the flight patterns of regional jets. Once this was accomplished, the second step was to analyze aircraft economics, aircraft utilization, airline scope clause agreements, and other factors to develop an understanding and explanation of the observed patterns. II. Methodology A. Data Sources To perform an analysis of emerging regional jet trends and compare them to those of other aircraft, this study made use of actual flight data from the aircraft situational display to industry (ASDI) feed. The ASDI feed provides aircraft position and speed information during flight, in addition to the flight origin, destination, and departure/arrival times. The ASDI feed is compiled from the Federal Aviation Administration’s (FAA’s) Enhanced Traffic Management System (ETMS) and is made available to vendors, who can then pass the data on to other interested parties. This study used ASDI data for one Thursday in January, between 1998 and 2003, resulting in a total of 6 days. Each data sample is from the same month and weekday to eliminate the effects of seasonal and weekly variations in airline operations. The specific dates were chosen to represent typical January days. In particular,

단일 안테나 GPS 수신기를 이용한 관성센서의 고장검출 및 분리

In this paper, a new fault detection and isolation algorithm fur inertial sensor system is proposed. To identify the inertial sensor fault, single antenna GPS receiver is used as an effective redundancy source. To use GPS receiver as redundancy for the inertial sensors, the algorithm to estimate the attitude and acceleration using single antenna GPS receiver is adopted. By using Doppler shift of carrier phase signal and kinetic characteristics of aircraft, attitude information of aircraft can be obtained at the coordinated flight condition. Based on this idea, fault diagnosis algorithm for inertial sensors using single antenna GPS based attitude is proposed. For more effective FDI, decision variables considering the aircraft maneuver are proposed. The effectiveness of the proposed algorithm is verified through the numerical simulations.

FDI for Inertial Sensor using Single Antenna GPS Receiver

In this paper, fault detection and isolation algorithm for inertial sensor system is proposed. To identify the inertial sensor fault, single antenna GPS receiver is used as an effective redundancy source. To use GPS receiver as redundancy for the inertial sensors, the algorithm to estimate the attitude and acceleration using single antenna GPS receiver is adopted. Using Doppler shift of carrier phase signal and kinetic characteristics of aircraft, attitude information of aircraft can be obtained through one GPS antenna at the coordinated flight condition. Based on this idea, fault diagnosis algorithm for inertial sensors using single antenna GPS based attitude is proposed. For more effective FDI, decision variable considering aircraft maneuver is considered. The effectiveness of the proposed algorithm is verified through the numerical simulations for the various cases.

Airborne vector magnetics mapping of remanently magnetised banded iron-formations at Rocklea, Western Australia

Strongly remanent magnetic sources such as those found in the banded iron-formations (BIFs) of the Hamersley Basin impair the interpretation of standard total magnetic intensity survey data. The use of aircraft attitude information, provided by the FALCONTM airborne gravity gradiometer (AGG) system, makes it possible to reference geographically the vector magnetic information collected by the fluxgate triad on board the aircraft. A full aircraft compensation processing method, allowing for permanent, induced and eddy current effects, provides usable vector magnetic data. These data supply valuable extra information for the interpretation of strongly remanent BIFs. An example using data from a FALCONTM survey near the Rocklea Dome in the Hamersley Basin demonstrates improved mapping of the BIFs by the use of the vector-residual magnetic intensity data.

Effect of Automatic Dependent Surveillance Broadcast (ADS-B) Transmission Quality on the Ability of Aircraft to Maintain Spacing in a Sequence

The effect of ADS-B update rate, latency and accuracy on the airborne spacing performance of a sequence of six aircraft in descent was investigated using fast time simulation. Two different spacing criteria based on constant distance (7 nmi) and constant time delay (60 s) were evaluated using a spacing guidance law between aircraft. The performance of three different compensation terms for ADS-B update rate, latency and accuracy was also assessed. Spacing performance indicators used were distance or time between aircraft, speed variation and throttle behaviour. Results show that constant time delay spacing remained more stable than constant distance spacing for degradations in ADS-B update rate, latency and accuracy. Constant distance spacing was sensitive to the quality of ADS-B aircraft position information whereas constant time delay spacing was sensitive to the quality of ADS-B aircraft position and speed information (particularly speed accuracy). Transmission loss compensation terms for update rate, latency and accuracy produced significant improvements in spacing guidance stability.

Airborne vector magnetics mapping of remanently magnetized banded iron formations at Rocklea, Western Australia

Strongly remanent magnetic sources such as those found in the banded iron formations (BIFs) of the Hamersley Basin impair the interpretation of standard total magnetic intensity survey data. The use of aircraft attitude information, provided by the FALCONTM airborne gravity gradiometer (AGG) system, makes it possible to reference geographically the vector magnetic information collected by the fluxgate triad on board the aircraft. A full aircraft compensation processing method, allowing for permanent, induced, and eddy current effects, provides usable vector magnetic data. These data supply valuable extra information for the interpretation of strongly remanent BIFs.An example using data from a FALCON survey near the Rocklea Dome in the Hamersley Basin demonstrates improved mapping of the BIFs by the use of the vector-residual magnetic intensity data.