Aircraft Weight Research Articles

Characterization of aircraft landing impact loads: Effects on vertical tire-pavement contact characteristics and pavement performance

The comprehensive understanding of the mechanistic behavior of airport pavements under aircraft landing loads is essential for ensuring safety and durability. Addressing the limited understanding on the interaction between aircraft landing gear and airport pavement during landing, this study proposed a measurement method for the vertical dynamic contact characteristics of tire-pavement interface and internal dynamic responses based on a laboratory dynamic test device. This involved the experimental design and testing method for the dynamic characteristics of landing gear landing loads, utilizing the Tekscan pressure measurement system to evaluate the vertical dynamic contact characteristics between the aircraft tires and pavement during landing. Through comparative analysis with the static results, the study revealed the importance of landing load measurements for mechanical response analysis and durability design of airport pavements. Additionally, the study investigated the dynamic response of airport pavements under different simulated aircraft landing speeds and weights, and further quantified the impact effects of aircraft landing loads on airport pavements. The results show that the vertical tire-pavement contact characteristics under landing impact are significantly different from those under static conditions, and need to be considered. The proposed quantitative equations with acceptable good fitting effect provided more accurate and efficient vertical load inputs for numerical simulation and durability design of airport pavements, which laid the foundation for understanding the failure mechanisms of airport pavement and enhancing the safety of aircraft and airport operation.

Detection of Cut-Out in Aluminum Plate Using Ultrasonic Guided Waves: A Finite Element Analysis

<div>Aluminum alloys serve a critical role in the aerospace industry, accounting for a significant amount of commercial aircraft weight. Despite the growing use of composite materials, aluminum remains important in airframe construction due to its lightweight, cost-effectiveness, and high strength potential. Structural integrity is critical in modern engineering, necessitating early diagnosis and localization of damage. To detect the flaws, cracks, and cut-out in the structures, structural health monitoring (SHM) systems are essential, with non-destructive testing (NDT) methodologies playing critical roles. Among these technologies, ultrasonic guided wave testing (UGWT) has gained popularity because of its capacity to propagate over long distances and detect subsurface faults. This article investigates the use of UGWs to identify cut-outs in aluminum plates. The numerical investigation has been carried out using commercially available finite element software Abaqus. The ultrasonic lamb waves are generated through the load. The results obtained in pristine and defected 2D aluminum plate has been compared with proper selection of actuation and sensing points. Further by changing the location of actuation and sensing points the shift of damage scattering components has been observed. After identification of reflected wave mode, the location of the cut-out can be predicted accurately.</div>

An Assessment of an Airline Company within the Scope of Circular Economy Based Waste Management

The rapid growth in the aviation sector has prompted the industry to act and develop new and sustainable business models due to the greenhouse gases and waste generated inherently by the sector. In this context, this study provides an assessment of identifiable areas and determinants of circular economy in an airline company, considering its environmental impacts. As a result of the assessment, it has been observed that the airline company conducts initiatives in reduction, reuse, and recycling, along with the management of cabin materials and waste segregation. Action plans are in place regarding the reduction, substitution, or elimination of single-use plastics in material selection. In order to mitigate both the environmental and economic impacts of paper consumption, the company is undertaking digitalization efforts within its business processes. The weight of aircraft is a crucial factor in the amount of fuel consumed and the quantity of CO2 emissions released. Therefore, airlines prefer to use lightweight materials inside the aircraft to reduce weight. Plastic catering materials are among these lightweight options. Unfortunately, due to the adverse environmental impacts of plastics, reducing their usage and, if possible, phasing them out are essential measures that airlines need to take. Consequently, the airline company under this study has removed the plastic outer packaging of the packaged materials used in the cabin. Furthermore, it continues its efforts to remove plastic materials used during catering services or replace them with biodegradable alternatives.

Analisis Perhitungan Weight And Balance pada Loadsheet dalam Menunjang Keselamatan Penerbangan pada Maskapai Air Asia di Bandar Udara Husein Sastranegara Bandung

The importance of calculating weight and balance on an aircraft to support flight safety is something that must be done by service providers. Mistakes in calculating weight distribution can cause overloads that risk endangering the safety of passengers, crew, and the aircraft itself. This study was conducted at AirAsia Airlines with a focus on the Airbus A320 aircraft at Husein Sastranegara Airport, Bandung. The study used a quantitative method with primary and secondary data collection. Primary data was collected through direct observation in the field, while secondary data was obtained from documents, journals, and related literature. This study analyzed data related to aircraft weight, fuel, passengers, baggage, and cargo to calculate weight and balance on the loadsheet. The results of this study indicate that calculating weight and balance on loadsheets is an important process in ensuring flight safety. Steps involving calculating the weight of passengers, baggage, cargo, fuel, and the distribution of the aircraft's center of gravity ensure that the aircraft operates within the safe limits set by the manufacturer. Based on the analysis of passenger, baggage, cargo, and fuel data, the Zero Fuel Weight (ZFW) was 60,516 kg, Takeoff Weight (TOW) was 67,516 kg, and Landing Weight (LW) was 62,516 kg. All of these parameters are within the specified safe limits. Load management on an Air Asia A320 aircraft when overloading requires special attention to parameters such as Maximum Takeoff Weight (MTOW), Maximum Landing Weight (MLW), and Maximum Landing Weight (MZFW). If an overload occurs, as recorded on the fourth day in Hold 5, the solution that can be taken is to reduce the cargo load on that Hold. For the situation on the fifth day, where the Landing Weight (LW) exceeds the MTOW, the right step is to reduce the amount of fuel.

Dispersion, solid solution, and covalent bond coupled to strengthen K4169/TiAl composite brazed joints: First-principles and experimental perspective

Ni/TiAl composite brazed joints could significantly reduce the aircraft's weight. However, low interfacial adhesion, coarse and brittle-hard intermetallic compounds (IMCs) seriously limited the application of Ni/TiAl composite joints in the next generation of aerospace applications. So enhanced K4169/TiAl composite joints were investigated by vacuum brazed with (Ni53.33Cr20B16.67Si10/Zr25Ti18.75Ta12.5Ni25Cu18.75) composite filler metal (CFM) designed based on cluster-plus-glue-atom model. The shear strength of the joint reached 485 MPa, comparable to the 491 MPa of TiAl substrate. The flat and brittle-hard diffusion reaction layer between Zones I and II was eliminated, simultaneously generating CrB4 dispersion strengthening due to the CFM developed with the interfacial solid-liquid space-time hysteresis effect. In Zones II and III, IMCs all transformed into Niss(Cr,Fe)[0–88], Niss(Ti, Al)[004], and Niss(Zr,Si)[11–2] of circular and oval shapes through isothermal solidification. Meanwhile, the residual stresses and hardness were distributed in reticulated cladding characteristics. Thereby, lattice distortion led to solid solution strengthening and increased plastic toughness through crack termination and bridging mechanisms, which inhibited dislocations from plugging and crack propagation. Various interfaces in Zone Ⅳ were regulated into semi- and coherent interfaces. Ni3(Ti,Al)/(Ni,Ti,Al) and (Ni,Ti,Al)/AlNi2Ti were composed of higher interfacial bonding energy (2.771 J/m2, 2.547 J/m2) and Ni-Ni covalent bonds. Interfacial covalent bonding and large interfacial bonding energy coupling strengthened Zone IV. Consequently, cracks initiated at the (Ni,Ti,Al)[013]/Ti3Al[010] and expanded rapidly into TiAl substrate. Therefore, applying this method to design CFMs and regulate the phase, grain morphology, and interface's fine structure could provide new pathways for dissimilar hard-to-join metals.

Influence on the properties of TMCs of ceramic and intermetallic composite reinforcements (B4C, TixAly and TixSiy) fabricated by inductive hot pressing

Ambitious and competitive, the aerospace industry continuously demonstrates to be one of the leading engineering sectors either at exigence and new technologies development. As lightning the weight of aircrafts is one of the main targets, the spotlight is usually on material research by which new ones may be produced to pursue this aim and still offer the necessary performances. The combination of the properties of titanium and other materials as reinforcements provides really interesting results as titanium matrix composite materials, also known as TMCs. Various samples of titanium matrix composite materials with different reinforcements have been under study to determine the influence of the reinforcements and their respective proportions on the properties of the material. These samples composed of grade 1 commercially-pure titanium as matrix and B4C, TixAly and TixSiy as reinforcements, have been manufactured through powder metallurgy in the same conditions of temperature and pressure via Inductive Hot Pressing (IHP). A total of eight composite materials have been arranged in several different groups to confront their compositions. Thus, this analysis reports results for the influence of the powder size of the matrix and the ceramic reinforcement, the effect of varying the volumetric composition of B4C, and the selection of different intermetallic reinforcements. These tests and the obtained information serve for a project in which the main goal is to determine which compositions of the studied composite materials reach a high enough specific stiffness for a suitable application in the aerospace industry.

Method of first-approximation calculation of take-off weight of a light aircraft with a hybrid propulsion system

The article discusses a method for calculating, as a first approximation, the take-off weight of a light aircraft with a hybrid power plant based on piston and electric engines. A brief overview of organizations dealing with hybrid power plants is given. The influence of the degree of hybridization of the power plant on the take-off weight of the aircraft is shown. The degree of hybridization of a power plant is understood as a relative value characterizing the distribution of the total power of all engines installed on the aircraft between piston and electric engines. The main parameters necessary to determine the take-off weight of an aircraft to a first approximation are presented. The take-off weight of the aircraft is determined to a first approximation from the equation of its existence. Statistical data of aircraft with different types of power plants are provided on the basis of which calculations are carried out. As a first approximation, the relative mass of the hybrid power plant is determined by analyzing the statistical data of light aircraft with piston and electric engines, from which the corresponding graphs are constructed. After the calculations, conclusions were drawn about the optimal range of characteristics of a light aircraft with a hybrid power plant.

Demonstration of an In-Flight Entertainment System Using Power-over-Fiber

The use of optical fibers is increasing in modern aircraft because this helps solve challenges of size, weight, communication, and reliability in new generation aircraft. This study describes a video and power transmission system using optical fibers (PoF) for in-flight entertainment (IFE) system application. We present the benefits and the limitations of this application, and we perform two practical experiments to demonstrate their performance. We used off-the-shelf devices in the experiments, such as one 15-Watt semiconductor laser operating at 808 nm, GaAs photovoltaic converters, optical transmitters and receivers, and video monitors. The power and video signals were transmitted using two 50-m length multimode fibers. In addition, we proposed and tested two types of energy transformation units (ETUs), which are responsible for supplying electrical energy to the IFE video monitor and the optical fiber receiver.

Aircraft Takeoff and Landing Weight Estimation from Surveillance Data

Aircraft weight estimation is a common problem facing researchers working with aircraft surveillance data. Although knowledge of an aircraft’s weight and thrust is required for many types of analyses, such as those evaluating aircraft acoustic noise, fuel burn, and emissions, these parameters are typically not available from surveillance sources. Instead, researchers generally only have access to basic aircraft states: lateral position, groundspeed, and altitude. Therefore, methods for estimating the weight of aircraft from these basic states become necessary in cases where aircraft performance is a key component of the analysis. This paper introduces two weight estimation models: one for the estimation of aircraft takeoff weight from departure data, and another for the estimation of aircraft landing weight from arrival data. The models are mathematically simple but grounded in knowledge of aircraft certification, airline operations, and aircraft flight management system logic. The landing weight estimation model proposed is shown to have a mean absolute error equivalent to 2.66% of maximum takeoff weight and a standard deviation of 3.35% of maximum takeoff weight when validated using onboard data recordings from 240 Airbus A320 flights. Similarly, the proposed takeoff weight estimation model is shown to have a mean absolute error of 2.83% of the maximum takeoff weight and a standard deviation of 3.55% of the maximum takeoff weight when applied to the same validation dataset.

Idealitas Weight and Balance pada Pesawat Tipe Comac ARJ21-700 Maskapai TransNusa di Bandar Udara Internasional Soekarno-Hatta

The calculation of weight and balance requires high accuracy so that the flight can be carried out safely to the destination airport. A number of obstacles that load control officers experience can affect the ideality of weight and balance and must be properly calculated. The purpose of this research is to determine the ideal weight and balance of Comac ARJ21-700 aircraft of TransNusa airline at Soekarno-Hatta International Airport. This research uses qualitative and quantitative methods using primary data obtained through observation and interviews, secondary data using documentation and literature studies. Data collection techniques used by observation, interviews and documentation. Interviews were conducted with supervisors and senior load control narrow body and junior load control. Data analysis techniques by means of data collection, data reduction, data presentation, and conclusion drawing. The results of this study are the obstacles of load control officers in calculating the weight and balance of Comac ARJ21-700 aircraft of TransNusa airline, namely the delay of check-in officers in inputting data on the number of passengers and luggage. Determination of the location of passengers and luggage is carried out by check-in officers, if there is a mismatch, the load control officer makes a request to the check-in officer to maximize the front compartment. The average center of gravity of the Comac ARJ21-700 shows at -7.29UP which states that the center of gravity of the Comac ARJ21-700 is -7.29UP.

Thermal-hydraulic performance of TPMS-based regenerators in combined cycle aero-engine

The existing regenerator structure in aero-engine cannot satisfy the requirements with the development of hypersonic vehicles. The triply periodic minimal surface (TPMS) with superior thermal and mechanical performances has great potential for the regenerator. However, the study on TPMS structures as heat exchangers with high compactness and high power-to-weight ratio is still lacking. This study presents a complete workflow for evaluating the performances of TPMS heat exchangers. Based on this workflow, the thermal–hydraulic performances of Diamond, Fischer-Koch S (FKS), and printed circuit heat exchangers (PCHE) at different Reynolds numbers are investigated. Compared with the PCHE, the performance evaluation criteria of Diamond and FKS structures increased by 11.3–26% and 10.9–32.5%, respectively. This can be mainly attributed to the intensive turbulent mixing, large wall shear stress and high specific surface area of the TPMS structures. The thermal–hydraulic performance is also well explained by the field synergy principle. Based on the developed thermal and hydraulic correlations, the TPMS regenerators are designed and the results indicate that the power-to-weight ratio is improved by about 4 times with half volume of a PCHE. In summary, the TPMS regenerators can save space, reduce weight, and increase payload of aircrafts and have great application potential in the field of aerospace.

Improved FPA for aircraft conceptual design

Aircraft weight design is a key technology in aircraft conceptual design. The design of aircraft weight is directly related to many design parameters of the aircraft, and there are complex constraint relationships between these parameters. It is difficult to determine the design parameters in the process of aircraft conceptual design with an accurate mathematical analytical model, it is necessary to use an optimization algorithm. Firstly, to build the optimization object function, the aircraft weight function and some constrain functions are given out, thus, the aircraft weight design problem is transformed into a single objective multi-constraint optimization problem, aiming at the problem of parameter coupling, Aitken acceleration algorithm is proposed to solve the problem through iterative, thus, and a feasible solution of aircraft parameters are obtained; Secondly, considering the advantages of flower pollination algorithms in solving unconstrained problems, the flower pollination algorithm (FPA) combined with the Aitken acceleration algorithm is proposed for automatic global optimization, to avoid the FPA falling into the local optimal solution or missing optimal solution, propose improvements to the FPA algorithm from three aspects: adaptive conversion probability, adaptive step size adjustment, and adaptive reproduction probability generation. To use FPA, the multi-constraint optimization problem is transformed into a multi-parameter unconstrained optimization problem with a penalty term based on the penalty function method. Finally, a design example is given to verify the effectiveness of the algorithm, and the superiority of the improved algorithm is verified by comparing it with PSO and the fixed transition probability FPA.

Thermodynamic analysis of power generation thermal management system for heat and cold exergy utilization from liquid hydrogen-fueled turbojet engine

Hydrogen propulsion is generally treated as the ultimate net zero-emission option for aviation, therein liquid hydrogen storage appears to provide the only feasible solution for aircraft with the constraints imposed by aircraft weight and volume. Hydrogen liquefaction consumes a great amount of energy, which significantly boosts the cost of hydrogen as an aviation fuel. Besides the H2 chemical exergy for combustion to provide thrust, the H2 physical exergy in the form of cold energy is also a kind of high-quality clean energy to produce power output, which offers great opportunities to achieve cost-effective use of hydrogen fuel. Thus, this paper presents a Rankine cycle and H2 direct expansion cycle (RC-DEC) combined power generation thermal management system for the simultaneous utilization of exhaust gas heat exergy and hydrogen fuel cold exergy from the liquid hydrogen-fueled turbojet engine. In the Rankine cycle, the transcritical mode is applied on the hot side while the liquid separation condensation concept is adopted on the cold side to achieve better thermal matchings with heat and cold sources. The hydrocarbon/inert gas binary mixture is proposed as the working fluid of the Rankine cycle. The effects of key thermodynamic parameters and the influence of Para-Ortho hydrogen conversion on system performance are discussed, then a comparison of the mixture working fluid is conducted. Results show that there exists an optimal separation temperature ratio and condensation pressure of RC to obtain maximum total net power output. As the DEC expander inlet pressure increases, the total net power output first increases and then levels off. The introduction of the Para-Ortho hydrogen conversion has a negligible impact on net power output but leads to a significant reduction in the exergy efficiency, which is attributed to the cold energy release nature of Para-Ortho hydrogen conversion. The results of the working fluid comparison indicate that the optimal inert gas retardant for CH4 is Kr, while those for C2H6 and C3H8 are Xe to achieve the maximum net power output and exergy efficiency of the proposed power generation system. Among them, C2H6/Xe(0.6/0.4) obtains the maximum net power output of 2717.9 kW and maximum exergy efficiency of 33.1%, which suggests an opportunity to provide megawatts of electrical power for the aircraft in place of the APU.

Aeronautical Infrastructure Optimization to Enhance the Strategic and Operational Business Performance of Small Airports

Airport business management literature commonly evaluates the performance of these organizations based on the number of passengers and cargo processed, aircraft movements, number of runways, number of employees, and passengers’ terminal dimension, among other factors concerning commercial aviation, commonly applied to large structures, with gaps being identified in the literature of small airports. The identification and analysis of the main factors that interfere with the performance of airport business, and the strategic and operational management of small public airports have been analyzed from 24 small Brazilian airports. The study employed the Data Envelopment Analysis method based on the Charnes, Cooper, and Rhodes model, as well as the Banker, Charnes, and Cooper model, adapted for Visual Basic Analysis. The main results demonstrate that infrastructural characteristics, such as runway width, pavement classification number, runway length, buldings' age, maximum take-off weight of the critical aircraft, passenger terminal size, and air cargo and passengers processed, show significant relevance to the operational performance of small airports. The main theoretical implications of the study are the definition of strategic and operational parameters that impact the performance of small airports, which can be used as a reference by air transport decision-makers.

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.

Paving the Way for the Electrified Future of Flight: Safety Criteria Development for Integrating Structural Batteries in Aircraft

AbstractWithin the global push towards environmental sustainability, the aviation industry is increasingly investigating electrification as a potential solution to reduce emissions and combat climate change. However, traditional battery integration faces significant drawbacks due to their limited energy and power densities, which negatively impact aircraft weight and performance. In this scenario, structural batteries are gaining interest, since they combine energy storage and load-bearing capabilities in multifunctional material structures, thus potentially eliminating barriers to the electrification of the air transport sector. While this novel technology holds immense potential, its integration raises new and unique airworthiness concerns. The present activity aims to support the development of aircraft certification requirements for structural batteries. Recognizing the dual nature of this technology, the proposed approach seeks to maintain or even enhance the current level of safety in both normal and emergency flight conditions.

Cruise range modeling of different flight strategies for transport aircraft using genetic algorithms and particle swarm optimization

Cruise flight profile accounts for the highest percentage of fuel consumption on long-haul flights, which makes the optimization of cruise range crucial for a net-zero, sustainable, secure, and affordable energy future. Therefore, flying at altitudes close to the optimum cruise altitude will significantly reduce fuel consumption and fuel-related emissions; It will also increase cruise range. In this context, accurate range calculations are critical to evaluate and understand the environmental and economic impacts of all aircraft. This paper proposes two novel non-conventional models of Genetic Algorithms (GA) and Particle Swarm Optimization (PSO) to estimate the cruise range of jet powered transport aircraft as a first attempt in the literature. Using both methods, non-linear models which provide range formulations dependent on velocity, aircraft weight and cruise flight altitude were developed for the cruise flight strategies including constant altitude-constant lift coefficient and constant altitude-constant Mach number. The accuracies of both derived models were analyzed and it was seen that both models are capable of providing satisfactory cruise range prediction results.

A large-scale validation study of aircraft noise modeling for airport arrivals.

In the U.S., the Federal Aviation Administration's Aviation Environmental Design Tool (AEDT) is approved to predict the impacts of aircraft noise and emissions. AEDT's critical role in regulatory compliance and evaluating the environmental impacts of aviation requires asking how accurate are its noise predictions. Previous studies suggest that AEDT's predictions lack desired accuracy. This paper reports on a large-scale study, using 200 000 flight trajectories paired with measured sound levels for arrivals to Runways 28L/28R at San Francisco International Airport, over 12 months. For each flight, two AEDT studies were run, one using the approved mode for regulatory filing and the other using an advanced non-regulatory mode with exact aircraft trajectories. AEDT's per aircraft noise predictions were compared with curated measured sound levels at two locations. On average, AEDT underestimated LAmax by -3.09 dB and SEL by -2.04 dB, combining the results from both AEDT noise-modeling modes. Discrepancies appear to result from limitations in the physical modeling of flight trajectories and noise generation, combined with input data uncertainties (aircraft weight, airspeed, thrust, and lift configuration) and atmospheric conditions.

Preliminary design of an ATC support tool for the implementation of the Ad Hoc Separation Minima concept in an en-route sector.

The current aim in response to the anticipated growth in air traffic demand is to expand airspace capacity. However, this poses a challenge, as many airspace volumes are nearing saturation. An influential factor in determining airspace capacity is separation minima, which have remained unchanged for more than two decades. It seems that technological developments in recent years, such as new aircraft capabilities and ATC (Air Traffic Control) support tools, may eventually enhance current separation minima standards. Consequently, there is a push to improve separation management by introducing new operational concepts. Ad Hoc separation minima are one such concept, allowing different separation values to be applied within the same airspace volume based on factors such as aircraft models, weights, and wind conditions, among others. These values are computed individually for each aircraft pair in each situation. Implementing different separation minima values within the same airspace volume requires a significant change in certain ATC activities. In addition, new functionalities or ATC support tools are essential, as Air Traffic Control Officers (ATCO) cannot mentally determine the appropriate separation value for each situation. To address this, a new tool, the Ad Hoc Separation Minima Tool (ASMT), is proposed. It aims to integrate this concept seamlessly into an en-route (ENR) sector without increasing ATCOs workload and altering ATC responsibilities. This study provides a high-level overview of the ASMT architecture, and its functional system has been evaluated in a simulated ENR sector using MATLAB®.

To Charge In-Flight or Not: A Comparison of Two Parallel Hybrid Electric Aircraft Configurations via Optimal Control

This study examines two configurations for parallel hybrid electric aircraft, one with a mechanical connection between the engines and the electric motors and the other without. A previously proposed power allocation algorithm in the context of aircraft energy management is applied to these two configurations for a 19-seat conceptual hybrid electric aircraft. The original optimal control problem is then transformed into a finite-dimensional optimization, and the second-order sufficient conditions for the global optimality of the obtained solution are validated. This is followed by a sensitivity analysis of the fuel consumption to the initial aircraft weight and flight duration. Simulation and theoretical results clarify the limited benefits of charging the battery in-flight for this class of hybrid electric aircraft for the purpose of reducing fuel consumption and CO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> emissions.