Aircraft Systems Research Articles

Evaluating the potential for efficient, UAS-based reach-scale mapping of river channel bathymetry from multispectral images

Introduction: Information on spatial patterns of water depth in river channels is valuable for numerous applications, but such data can be difficult to obtain via traditional field methods. Ongoing developments in remote sensing technology have enabled various image-based approaches for mapping river bathymetry; this study evaluated the potential to retrieve depth from multispectral images acquired by an uncrewed aircraft system (UAS).Methods: More specifically, we produced depth maps for a 4 km reach of a clear-flowing, relatively shallow river using an established spectrally based algorithm, Optimal Band Ratio Analysis. To assess accuracy, we compared image-derived estimates to direct measurements of water depth. The field data were collected by wading and from a boat equipped with an echo sounder and used to survey cross sections and a longitudinal profile. We partitioned our study area along the Sacramento River, California, USA, into three distinct sub-reaches and acquired a separate image for each one. In addition to the typical, self-contained, per-image depth retrieval workflow, we also explored the possibility of exporting a relationship between depth and reflectance calibrated using data from one site to the other two sub-reaches. Moreover, we evaluated whether sampling configurations progressively more sparse than our full field survey could still provide sufficient calibration data for developing robust depth retrieval models.Results: Our results indicate that under favorable environmental conditions like those observed on the Sacramento River during low flow, accurate, precise depth maps can be derived from images acquired by UAS, not only within a sub-reach but also across multiple, adjacent sub-reaches of the same river.Discussion: Moreover, our findings imply that the level of effort invested in obtaining field data for calibration could be significantly reduced. In aggregate, this investigation suggests that UAS-based remote sensing could facilitate highly efficient, cost-effective, operational mapping of river bathymetry at the reach scale in clear-flowing streams.

A new high-frequency multilevel inverter effecting cables weight and energy efficiency of aircraft

Purpose Static inverters are very important for the emergency energy distribution system of aircraft and similar machines. At the same time, the electrical energy produced at high frequency for electrical devices is used to reduce the weight of the cables in the aircraft and spacecraft because of the skin effect. In the high-frequency system, a thinner cable cross-section is used, and a great weight reduction occurs in the aircraft. So, fuel economy, less and late wear of the materials (landing gear, etc.) can be obtained with decreasing weight. This paper aims to present the development of a functional multilevel inverter (FMLI) with fractional sinus pulse width modulation (FSPWM) and a reduced number of switches to provide high-frequency and quality electrical energy conversion. Design/methodology/approach After the production of FSPWM for FMLI with a reduced component, which, to the best of the authors’ knowledge, is presented for the first time in this study, is explained step by step, and eight operating states are given according to different FSPWMs operating the circuit. The designed inverter and modulation technique are compared by testing the conventional modular multilevel inverter on different loads. Findings According to application results, it is seen that there is a 50% reduction in cross-section from 100 Hz to 400 Hz with the skin effect. At 1000 Hz, there is a 90% cross-section reduction. The decrease can be in cable weights that may occur in aircraft from 10 kg to 100 kg according to different frequencies. It causes less harmonic distortion than conventional converters. This supports the safer operation of the system. Compared to the traditional system, the proposed system provides more amplitude in converting the source to alternating voltage and increases the efficiency. Practical implications FSPWM is developed for multilevel inverters with reduced components at the high frequency and cascaded switching studies in the power electronics of aircraft. Social implications Although the proposed system has less current and power loss as mentioned in the previous sections, it contains fewer power elements than conventional inverters that are equivalent for different hardware levels. This not only reduces the cost of the system but also provides ease of maintenance. To reduce the cable load in aircraft and create more efficient working conditions, 400 Hz alternative voltage is used. The proposed system causes less losses and lower harmonic distortions than traditional systems. This will reduce possible malfunctions and contribute to aircraft reliability for passengers and cargo. As technology develops, it is revealed that the proposed inverter system will be more efficient than traditional inverters when devices operating at frequencies higher than 400 Hz are used. With the proposed inverter, safer operation will be ensured, while there will be less energy loss, less fuel consumption and less carbon emissions to the environment. Originality/value The proposed inverter structure shows that it can provide energy transmission for electrical devices in space and aircraft by using the skin effect. It also contains less power elements than the traditional inverters, which are equivalent for different levels of hardware.

Research on Improvement Methods for Driven System of Bio-Inspired Aircraft to Increase Flight Speed

The flapping-wing ornithopter is an aircraft that imitates the flight of birds in nature. It has significant potential and value in various fields such as surveying, search and rescue, military reconnaissance, and unmanned warfare, due to its biomimetic stealth and high efficiency in low Reynolds number flight. However, the cruising speed of current flapping-wing ornithopters is generally lower than that of birds of the same size, which seriously affects biomimicry, mission capability, and wind resistance. Increasing the cruising speed can make the aircraft fly more like a bird, improve the efficiency of reconnaissance missions and wind resistance per unit time, and has important research significance. However, the methods to increase the cruising speed of flapping-wing ornithopters are currently lacking. Firstly, this paper presents improvements to the propulsion system based on the team’s “Dove” aircraft to meet the speed requirements. The actual flapping frequency and rocking arm end torque of the “Dove” aircraft under different voltages are tested. To select and match the motor and gearbox in the propulsion system, a method for matching and selection among the motor, gearbox, and load is proposed. Finally, wind tunnel experiments and flight validations are conducted on the improved flight prototype. The wind tunnel experiments show that the increase in flapping frequency has a significant impact on thrust. The trimmed states at different speeds are obtained. The flight validation demonstrates the sustained high-speed flight capability of the aircraft. At a flapping frequency of approximately 15 Hz, the average flight speed of the aircraft is 13.3 m/s within a 15 min duration, which is close to the actual flight speed of pigeons. The duration of high-speed flight is tripled compared to the initial duration. The speed improvement successfully enhances the biomimicry and efficiency of reconnaissance missions per unit time for the aircraft.

Research on optimal power flow of AC/DC hybrid system for civil more electric aircraft

Modern civil more electric aircraft often use AC/DC systems instead of AC systems to reduce the weight of the power system. Compared with the AC/DC system of the land power grid, the aircraft power system needs to pursue economic operation mode under more complex security constraints. This paper establishes the optimal power flow model of the AC/DC hybrid system of more electric aircraft, which takes minimizing the active power loss of the line as the optimization objective, including the steady-state operation constraints and security constraints of the AC/DC system. The interior point method and prediction correction interior point method are used to solve the model. Then, based on the simplified steady-state model of the B787 power system, the model and algorithm are verified by experiments. The experimental results show that by optimizing the power flow distribution of the power system, the power utilization efficiency of the system has been significantly improved, and its stability and reliability can also be better guaranteed.

Evidence of the potential benefits of digital technology integration in Asian agronomy and forestry: A systematic review

CONTEXTThe agronomy–livestock–forestry nexus is critical as it influences ecosystem services, food production, and land use. Asia, a diverse and technologically dynamic region, faces disparities in agronomy tech adoption. Studies emphasize agronomy and forestry's pivotal role in determining livelihoods in the region. Challenges like rising food demand, land scarcity, climate change, and biodiversity loss require innovative solutions. Digital technologies offer enhanced productivity, sustainability, and resource management opportunities, defining the era of smart agriculture and forestry. OBJECTIVESThis work presents a Systematic Literature Review (SLR), which examines the potential for using digital technology in agronomy and forestry across Asian countries and evaluates evidence of the potential benefits for practitioners and the environment. METHODSThe Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method guided the choice of relevant publications. Of the 375 papers located in Scopus and Web of Science (WoS) databases, only 24 were considered relevant to the research questions. RESULTS AND CONCLUSIONSIn the agronomy and forestry sectors in Asia, the adoption of digital technologies has the potential to contribute toward the promotion of biodiversity, the preservation of ecosystem services, improved labor efficiency, risk reduction, and the promotion of climate change resilience. Geospatial tools, modeling tools, decision support systems, Unmanned Aircraft Systems (UAS), and the Internet of Things (IoT) have emerged as prominent technologies driving these positive outcomes. The study lists evidence from various articles supporting these benefits, although most demonstrate indirect causation. This underscores the need for more direct experiments to establish the broader contribution of digital technologies as well as provide evidence showing farmer uptake and the potential negative impacts of implementation. SIGNIFICANCEThe findings from this study offer a comprehensive view of the potential use of digital technologies for agronomy and forestry in Asia, as well as evidence of their potential benefits. It gives stakeholders valuable information on digital technologies and provides a springboard for future studies regarding the application of digital technology in agronomy, animal husbandry, and forestry.

Summary of Failure Conditions Recorded in Selected Helicopters Operated by Army Air Corps

This paper has been drawn up for the Air Operations Group and the Technical Maintenance Group of the 56th Air Force Base in Inowrocław (Poland). Its primary purpose is to compare the frequency of failure conditions and their impact on the safety of flights performed on Mi-24 and W-3PL helicopters. Special attention has been paid to the values of flight parameters recorded and any anomalies identified. The data were analyzed using the "Objective Record Analysis" software, with two aspects taken into consideration. The first aspect – failure conditions which do not affect flight safety, i.e. when the crew exceeded the permissible flight parameters for a given exercise, an interference took place, a calculation error occurred in the system or the equipment became uncalibrated. A total of 534 failure states were singled out, with 18% of them caused by the human factor. The remaining 82% occurred due to interference and errors in the recording system or due to an incorrect flight parameter recording process (with this factor remaining beyond the control of the flight crew or maintenance personnel). The second aspect focused on failure conditions having an impact on flight safety, i.e. when the crew exceeded the aircraft's operating envelope or damage to the aircraft's systems and components occurred. 1,075 states have been recorded, with safety violations caused by exceeding the aircraft’s operating limits accounting for 5% of them. Damage to aircraft systems and components was the root cause of the 95% of the failures (with emergency landings required in 6 cases). It was shown that 80% of the failure conditions studied occurred on the Mi-24, with the number of missions performed on this particular type being nearly twice as high as on the W-3PL. Analysis of the years to which the available data was related (2012-2016) has led to the conclusion that the number of flights performed and the number of failure conditions was on an increase. However, the share of failure conditions in the total number of flights decreased. Authors 1 and 2 serve in the 56th Air Force Base and were granted permission to access and publish the data presented in this paper.

Dynamic modeling of the electrical actuation system of the hypersonic aircraft considering the temperature effects

Dynamic modeling of the electrical actuation system of the hypersonic aircraft considering the temperature effects

Creep behavior and precipitation evolution of Mg-13Gd-2Y-0.5Zr alloy

With exceptional aging hardening effect and a heat resistance temperature up to 250 °C, MgGd alloys have great application prospects in heat-resistant components in new energy vehicle power systems, aviation and aircraft systems, atc. In this study, the creep properties of the Mg-13Gd-2Y-0.5Zr (GW132) alloy at 200–270 °C/ 110–150 MPa are investigated, and the constitutive equation of the steady creep rate is constructed, focusing on the evolution of the precipitated phase in the α-Mg matrix at 250 °C/150 MPa. The alloy exhibits good creep resistance at 200–250 °C/ 110–150 MPa and 270 °C/ 110 MPa. During creep at 250 °C/ 150 MPa for 200 h, the evolution sequence of α-Mg matrix precipitates is mainly β’ phase → β’ + β1 phase → β’ + β1 + β + 18R-LPSO phase, β’, β1, β and 18R-LPSO phases can coexist in the same creep state. The β’ phase is maintained at a large volume fraction and forms a string with the β1 phase. The string-like precipitates are connected to each other to form a continuous dense grid module. Moreover, the β’ phase and the 18R-LPSO phase have excellent high-temperature thermal stability and are coherent with the α-Mg matrix, enabling the alloy to have excellent creep resistance in a certain temperature range. The creep mechanism of the GW132 alloy at 250 °C/ 150 MPa is dominated by the diffusion of Gd and Y atoms and the dislocation slip.

NAVIGATOR PREPARATION DURING SPRAYING BY UAVS

The article presents the results of research on the implementation of navigator preparation duringagricultural spraying, conditioning the safe and precise performance of the task. This assumptionwas confirmed during spraying with unmanned aerial vehicles carried out in 2021–2023. Theexperience gained and conclusions enabled the development of a concept of initial and directnavigational preparation for unmanned aircraft systems performing spraying. It is also possibleto use this algorithm to perform deactivation by drones. The results obtained from the conductedaerial tests (within two scenarios: agricultural spraying and decontamination) have also shown thatthe risk analysis methodology recommended by EASA (SORA) entails a number of limitations andcannot be applied during spraying as it causes gaps in safety management. Therefore, a proprietaryEPEP risk analysis method has been developed specifically for spraying, which allows the pilot,the operator of an unmanned aircraft, to perform a risk analysis and manage it accordinglyimmediately before performing the task, compensating or minimizing the hazards that should beat an acceptable level before spraying.

VOLUMETRIC QUANTIFICATION OF EUCALYPTUS SP. STANDS THROUGH AERIAL PHOTOGRAPHS OBTAINED BY RPAS

Volumetric quantification of Eucalyptus sp. stands through aerial photographs obtained by RPAS. The data collection for forest management is necessary to carry out the inventory, being a procedure that requires field work, high cost and time. Therefore, the objective of this work was to develop dendrometric equations based on aerial images of RPAS (Remotely Piloted Aircraft System) combined with the manipulation of vector data, and to estimate the forest production of Eucalyptus sp., in the southern region of the state of Rondônia. The extraction of the variables crown projection area (ACRPAS) and total height (hRPAS) were derived from RPAS images, these have been validated from data obtained in the field by means of forest inventory and by standing trees rigorous scaling. Diametric and volumetric equations were adjusted according to the variables obtained by RPAS. The total height (h) of the scaled trees and hRPAS did not show significant differences (X²= 31.013). When comparing the estimates obtained by the v equation with their respective values of the scaling, it is verified that the v equation is accurate for estimates of the variable under study (X²= 0.8077). The results indicated success in tree detection, even with the difficulties in delimiting the crowns due to occlusion. Despite the challenges arising from flight altitudes below 250 m, the estimates of diameter, height, and individual volume using metrics derived from RPAS products were accurate, consistent with those obtained in the traditional forest inventory. The use of RPAS for volumetric quantification of forest stands in Rondônia represents an innovative approach in the sector, despite the challenges encountered.

Operational wind and turbulence nowcasting capability for advanced air mobility

The present study introduces “WindAware”, a wind and turbulence prediction system that provides nowcasts of wind and turbulence parameters every 5 min up to 6 h over a predetermined airway over Chicago, Illinois, USA, based on 100 m high-resolution simulations (HRSs). This system is a long short-term memory-based recurrent neural network (LSTM-RNN) that uses existing ground-based wind data to provide nowcasts (forecasts up to 6 h every 5 min) of wind speed, wind direction, wind gust, and eddy dissipation rate to support the Uncrewed Aircraft Systems (UASs) safe integration into the National Airspace System (NAS). These HRSs are validated using both ground-based measurements over airports and upper-air radiosonde observations and their skill is illustrated during lake-breeze events. A reasonable agreement is found between measured and simulated winds especially when the boundary layer is convective, but the timing and inland penetration of lake-breeze events are overall slightly misrepresented. The WindAware model is compared with the classic multilayer perceptron (MLP) and the eXtreme Gradient Boosting (XGBoost) models. It is demonstrated by comparison to high-resolution simulations that WindAware provides more accurate predictions than the MLP over the 6 h lead times and has almost similar performance as the XGBoost model although the XGBoost’s training is the fastest using its parallelized implementation. WindAware also has higher prediction errors when validated against lake-breeze events data due to their under-representation in the training dataset.

Application of Reliability Centred Maintenance in Improving Aircraft Availability with Preventive Maintenance Intervention

Aircraft are intricate flying machines equipped with advanced technologies and state-of-the-art information and communication systems. Maintaining these aircraft to ensure maximum availability and minimal downtime is a critical and challenging task. Therefore, aircraft maintenance, repair, and servicing are of utmost importance. This research work aims to develop a methodology for reliability centred maintenance (RCM) to enhance aircraft availability. An RCM approach with the Multi attribute decision making (MADM) technique for assigning criticality of systems was implemented to improve aircraft availability. Failure mode and effects analysis (FMECA) was utilized for the failure investigation in the aircraft systems. However, instead of the Risk priority number (RPN) due to its inherent flaws, the Analytical hierarchy process (AHP) was utilized to evaluate the criticality of systems. The remedial measures to minimize the failure frequency and downtime were proposed. The improvement in availability, post implementation of proposed preventive maintenance was validated with positive results. An improvement of approximately 6.62% in availability and a reduction of about 15.71% in the total downtime was observed on the implementation of proposed preventive measures. The availability analysis was carried out for aircraft systems; however, the model could also be used for other repairable systems following a similar maintenance philosophy.

Research on Cogging Torque Reduction of Direct-Drive Type Dual-Rotor Radial Flux Permanent Magnet Synchronous Motor for Electric Propulsion Aircraft

The direct-drive type high-torque-density motor is one of the most promising solutions of electric propulsion for aircraft. The cogging torque of the direct-drive motor causes torque ripple, vibration, and noise, which seriously affect the stability and reliability of the electric propulsion system for aircraft. In this paper, a novel direct-drive type high-torque-density dual-rotor radial flux permanent magnet synchronous motor (DRPMSM) is proposed, and its cogging torque is weakened by permanent magnet shape design and pole-arc coefficient combination. An eccentric and chamfered permanent magnet shape is proposed, and the influence of eccentric distance and chamfer angle on cogging torque is clarified. Through the pole-arc coefficient combination design of the inner and outer rotors of the DRPMSM, the cogging torques of the inner and outer rotor are phase reversed, thus further reducing the total cogging torque of the DRPMSM. By employing the response surface method, a mathematical model is established for the cogging torque of the DRPMSM in relation to the pole-arc coefficients, chamfer angle, and eccentric distance of the permanent magnets. The parameters that minimize the cogging torque of the DRPMSM are obtained using a genetic algorithm. A prototype is manufactured according to the optimized parameters, and experimental results validate the correctness of the theoretical analysis and the effectiveness of the optimization design method.

Fuzzy Modeling Framework Using Sector Non-Linearity Techniques for Fixed-Wing Aircrafts

This paper presents a mathematical modeling approach utilizing a fuzzy modeling framework for fixed-wing aircraft systems with the goal of creating a highly desirable mathematical representation for model-based control design applications. The starting point is a mathematical model comprising fifteen non-linear ordinary differential equations representing the dynamic and kinematic behavior applicable to a wide range of fixed-wing aircraft systems. Here, the proposed mathematical modeling framework is applied to the AIRBUS A310 model developed by ONERA. The proposed fuzzy modeling framework takes advantage of sector non-linearity red techniques to recast all the non-linear terms from the original model to a set of combined fuzzy rules. The result of this fuzzification is a more suitable mathematical description from the control system design point of view. Therefore, the combination of this fuzzy model and the wide range of control techniques available in the literature for such kind of models, like parallel and non-parallel distributed compensation control laws using linear matrix inequality optimization, enables the development of control algorithms that guarantee stability conditions for a wide range of operations points, avoiding the classical gain scheduling schemes, where the stability issues can be extremely challenging.

New Concept of Smart UAS-GCP: A Tool for Precise Positioning in Remote-Sensing Applications

Today, ground control points (GCPs) represent indispensable tools for products’ georeferencing in all the techniques concerning remote sensing (RS), particularly in monitoring activities from unmanned aircraft system (UAS) platforms. This work introduces an innovative tool, smart GCPs, which combines different georeferencing procedures, offering a range of advantages. It can serve three fundamental purposes concurrently: (1) as a drone takeoff platform; (2) as a base station, allowing the acquisition of raw global navigation satellite system (GNSS) data for post-processed kinematic (PPK) surveys or by providing real-time GNSS corrections for precision positioning; (3) as a rover in the network real-time kinematic (NRTK) mode, establishing its position in real time with centimetric precision. The prototype has undergone testing in a dedicated study area, yielding good results for all three geodetic correction techniques: PPK, RTK, and GCP, achieving centimeter-level accuracy. Nowadays, this versatile prototype represents a unique external instrument, which is also easily transportable and able to connect to the GNSS RING network, obtaining real-time positioning corrections for a wide range of applications that require precise positioning. This capability is essential for environmental applications that require a multitemporal UAS-based study. When the real-time RING data are accessible to the scientific community operating in RS surveying, this work could be a helpful guide for researchers approaching such investigations.

Temporal Logic Explanations for Dynamic Decision Systems Using Anchors and Monte Carlo Tree Search (Abstract Reprint)

For many automated perception and decision tasks, state-of-the-art performance may be obtained by algorithms that are too complex for their behavior to be completely understandable or predictable by human users, e.g., because they employ large machine learning models. To integrate these algorithms into safety-critical decision and control systems, it is particularly important to develop methods that can promote trust into their decisions and help explore their failure modes. In this article, we combine the anchors methodology with Monte Carlo Tree Search to provide local model-agnostic explanations for the behaviors of a given black-box model making decisions by processing time-varying input signals. Our approach searches for descriptive explanations for these decisions in the form of properties of the input signals, expressed in Signal Temporal Logic, which are highly likely to reproduce the observed behavior. To illustrate the methodology, we apply it in simulations to the analysis of a hybrid (continuous-discrete) control system and a collision avoidance system for unmanned aircraft (ACAS Xu) implemented by a neural network.

LaterAnalysis of the energy efficiency of an environmental control system of a passenger aircraft by using the entropy-statistical method

BACKGROUND: Aviation designers are striving to increase fuel efficiency of aircraft, including by increasing the efficiency of aircraft environmental control systems by reducing losses in its components.
 AIM: This study performs an entropy-statistical analysis of the environmental control system of a passenger aircraft assesses efficiency losses in the units included in it.
 MATERIALS AND METHODS: A static mathematical model of an environmental control system with moisture content control was developed to calculate the system parameters in various operating modes, for which an entropy-statistical analysis was performed.
 RESULTS: Using entropy-statistical analysis, the main units of the system were examined, their influence on the overall efficiency of the environmental control system was assessed, and the advantages of the given method of entropy-statistical analysis for such systems were outlined. The mathematical model was developed using the Matlab Simulink software package.
 CONCLUSIONS: A static mathematical model of an environmental control system with a three-wheel air cycle machine unit and a “loop” high-pressure dehumidification system was developed. An entropy-statistical analysis of the system was performed. The influence of the units included in the system on the efficiency of the system as a whole was assessed.

The heat transfer mechanism coupling pyrolysis and flow of hydrocarbon fuel in heated tube under supercritical pressure

The coupling mechanism between pyrolysis and fluid flow of endothermic hydrocarbon fuels plays a crucial role in the design of regenerative cooling systems for advanced aircraft. In this work, the convective heat transfer for HF-1 with pyrolysis including 18 species and 24 reactions is numerically investigated in a horizontal circle tube under supercritical pressure (5 MPa). The results show that the mechanism of small molecule products on different heat transfer phenomena varies. In the inlet heat transfer deterioration region, small molecule products exacerbate the non-uniform radial distribution of fluid density and dynamic viscosity. At the outlet position, it significantly enhances the physical heat sink of the mixture with its high thermal conductivity and specific heat capacity. Additionally, the aromatic hydrocarbons significantly contribute to non-uniformities in thermal conductivity and specific heat capacity due to the low specific heat capacity and thermal conductivity in inlet HTD region. When the radial non-uniformity coefficient of fuel conversion keeps between −0.1 and 0, the pyrolysis of the fuel enhances heat transfer, remarkably.

Optimisation of a liquid cooling system for eVTOL aircraft: Impact of sizing mission and battery size

High-energy and -power density lithium-ion batteries (LiB) can enable viable electric vertical take-off and landing (eVTOL) aircraft for advanced air mobility provided that their battery thermal management system (BTMS) allows safe and efficient operations with acceptable weight penalties and capacity degradation. In this paper, we present the first optimisation of a liquid-cooled LiB BTMS for a notional tilt-wing reference eVTOL aircraft. Using an in-house developed BTMS sizing and battery degradation modelling algorithm, we investigate the effects of cruise altitude, hover duration, and battery pack oversizing on BTMS weight and battery lifetime. We minimise the BTMS weight, power, and battery temperature. The optimisation results reveal that varying cruise altitude has a negligible effect on BTMS design. While an extended hover duration does not adversely impact degradation, a considerably heavier BTMS is needed. The BTMS is about twice as heavy when the hover duration increases from one to seven minutes. Shortening the flight distance or oversizing the battery pack greatly impacts the battery lifespan. The battery capacity degradation rate halves when increasing the battery pack size by 20%.

RPAS operations in urban airflow: Efficient modelling of representative wind speed variations along a flight path through a flow field with changing turbulence characteristics

For remotely piloted aircraft systems (RPAS) operating in the urban environment, the flight path will most likely pass through the turbulent airflow of building wakes. To attenuate or reject instabilities caused by the turbulent airflow, control systems strategies are being developed in preparation for increased demand on the smaller urban air mobility vehicles. In this paper, results from urban airflow measurements of four 1:300 scaled Canadian city model flow fields are examined to provide detailed understanding of flow characteristics that can be found in typical Canadian cities. The results show common patterns for the range of inner city wind speed and turbulence intensity but that within the urban boundary layer (UBL) the variation of flow characteristics does not have a gradient with respect to altitude and that flow characteristics are highly variable along representative flight paths. For the purpose of simulation of RPAS response to the complex urban airflow, methods for using real urban flows data as inputs to simulations is presented. Demonstration of an Advancing Fourier Series (AFS) method, using the measured city data, shows successful preservation of the spatial- and temporal-correlations for reconstruction of a flow time series offering a novel, efficient and flexible approach for implementation of a time-based simulation of RPAS response in complex flow environments such as the urban environment.