Distance Flown Research Articles

Machine-Learning Methods Estimating Flights’ Hidden Parameters for the Prediction of KPIs

Complex microscopic simulation models of strategic Air Traffic Management (ATM) performance assessment and decision-making are hindered by several factors. One of the most important is the existence of hidden parameters—such as aircraft take-off weight (TOW) and the selected cost index (CI)—which, if known, would allow for more effective performance modeling methodologies for assessing Key Performance Indicators (KPIs) at various levels of abstraction/detail, e.g., system-wide, or at the level of individual flights. This research proposes a data-driven methodology for the estimation of flights’ hidden parameters combining mechanistic and advanced Artificial Intelligence/Machine Learning (AI/ML) models. Aiming at microsimulation models, our goal is to study the effect of these estimations on the prediction of flights’ KPIs. In so doing, we propose a novel methodology according to which data-driven methods are trained given optimal trajectories (produced by mechanistic models) corresponding to known hidden parameter values, with the aim of predicting hidden parameters’ values of unseen trajectories. The results show that estimations of hidden parameters support the accurate prediction of KPIs regarding the efficiency of flights: fuel consumption, gate-to-gate time and distance flown.

Flight capacity and behavior of Ephestia kuehniella (Lepidoptera: Pyralidae) in response to kairomonal and pheromonal stimuli.

Flight behavior is an important component to understand in the context of pest management. However, because of their small size, little is known about the flight capacity of most stored-product insects, and when a flight has been assessed, it usually consists of a propensity for initiating flight. Despite a priori expectations of the importance of flight for moths, there are no data about the flight capacity and little on the flight behavior of the Mediterranean flour moth, Ephestia kuehniella Zeller (Lepidoptera: Pyralidae). As a result, the objective of the current study was to (i) characterize the baseline flight capacity of E. kuehniella and (ii) determine how flight capacity is affected by the presence of kairomonal, pheromonal, or no stimuli. We found adult E. kuehniella flew a mean of 24-34 km in a 24-h period, and the distance flown per bout increased from 91 to 207 m in the presence of pheromones but decreased to 41 m when food was nearby compared to a negative control. The total number of flight bouts was 1.6-fold higher in the presence of pheromone compared to the negative control, but E. kuehniella flew significantly slower with pheromone and food cues present, suggesting they may be exhibiting an optimal foraging strategy. Our data on flight capacity results in qualitatively and quantitatively different conclusions about flight than those conclusions formed if only flight initiation is considered. Overall, this novel information is useful for understanding the spread within facilities and in the landscape (between facilities), as well as parameterizing ecological modeling.

Optimization of avian perching manoeuvres

Perching at speed is among the most demanding flight behaviours that birds perform1,2 and is beyond the capability of most autonomous vehicles. Smaller birds may touch down by hovering3–8, but larger birds typically swoop up to perch1,2—presumably because the adverse scaling of their power margin prohibits hovering9 and because swooping upwards transfers kinetic to potential energy before collision1,2,10. Perching demands precise control of velocity and pose11–14, particularly in larger birds for which scale effects make collisions especially hazardous6,15. However, whereas cruising behaviours such as migration and commuting typically minimize the cost of transport or time of flight16, the optimization of such unsteady flight manoeuvres remains largely unexplored7,17. Here we show that the swooping trajectories of perching Harris’ hawks (Parabuteo unicinctus) minimize neither time nor energy alone, but rather minimize the distance flown after stalling. By combining motion capture data from 1,576 flights with flight dynamics modelling, we find that the birds’ choice of where to transition from powered dive to unpowered climb minimizes the distance over which high lift coefficients are required. Time and energy are therefore invested to provide the control authority needed to glide safely to the perch, rather than being minimized directly as in technical implementations of autonomous perching under nonlinear feedback control12 and deep reinforcement learning18,19. Naive birds learn this behaviour on the fly, so our findings suggest a heuristic principle that could guide reinforcement learning of autonomous perching.

Flight Mill Experiments and Computer Simulations Indicate Islands Recruit More Capable Flyers of Moths

Understanding the traits related to species colonization and invasion, is a key question for both pest management and evolution. One of the key components is flight, which has been measured for a number of insect species through radar and tethered flight mill systems, but a general understanding of insect flight at a community level is lacking. In this study, we used flight mill experiments to quantify flight abilities of moth species, and simulation experiments to study which moths in mainland China have the potential for cross-island dispersal. We found that moths from superfamily Geometroidea (family Geometridae) have the weakest flight ability among the seven Lepidoptera superfamilies, which is characterized by the shortest longest single flight (LSF), the shortest time corresponding to the longest single flight (TLSF) (timecorrespondingtothelongestsingleflight), the lowest total distance flown (TDF), and the lowest average speed during the flight (VTDF). Surprisingly, the family Pyralidae (superfamily Pyraloidea) has the highest flight endurance of all 186 species of 12 families in this study, which is unexpected, given its small size and morphological traits yet it shows the longest LSF and TLSF. The comparison between species common to mainland and islands shows that flight distance (LSF) may be more important for species spread than flight speed. The results of mainland-island simulations show that when P(LSF>CD) (the proportion of individuals whose LSF is greater than the closest distance (CD) between mainland and island to the total number of individuals in the population) is less than 0.004, it is difficult for moth species to disperse to across islands without relying on external factors such as airflow. Over extended periods, with the immigration of species with strong flight abilities, islands are more likely to recruit species with stronger flight abilities.

High Temperatures Decrease the Flight Capacity of Diaphorina citri Kuwayama (Hemiptera: Liviidae).

Simple SummaryFlight capacity is directly associated with the spread of vector-transmitted plant pathogens. However, vector flight capacity could be affected by environmental conditions such as temperature and humidity. Here, we studied the effect of high temperatures and humidity in the flight capacity of Diaphorina citri, the main vector of the Huanglongbing disease of citrus. Our data suggest that high heat environments affect the propensity of D. citri to engage in long-distance flights, as well as the duration and distance flown, regardless of the humidity level. This information is fundamental to understand the dispersion of D. citri under different environmental conditions. Diaphorina citri Kuwayama (Hemiptera: Liviidae), commonly known as Asian citrus psyllid (ACP), is an invasive insect pest and the vector of the bacterium causing Huanglongbing (HLB), a lethal disease of citrus. In the United States, ACP has been established in all citrus-producing zones, all of which have different environmental conditions. The spread of ACP and, more importantly, HLB, has progressed differently depending on the state, with more rapid spread in Florida and Texas than in California. Climatic variations between the regions are likely a strong factor in the difference in the rate of spread. Despite this, it is unknown how the flight capacity of D. citri is influenced by high temperatures (>30 °C) and subsequently, low humidity experienced in California but not in Texas or Florida. In this study, by using a custom-made, temperature-controlled flight mill arena, we assessed the effect of high temperatures on the flight capacity and flight propensity of D. citri under low (20–40%) and high (76–90%) relative humidity conditions. We found that temperature and humidity influence the propensity to engage in short or long-distance flight events. Psyllids exposed to temperatures above 43 °C only performed short flights (˂60 s), and a high relative humidity significantly decrease the proportion of long flights (≥60 s) at 26 and 40 °C. The flight capacity for insects who engaged in short and long flights was significantly affected by temperature but not by humidity. For long flyers, temperature (in the 26–43 °C range) was negatively correlated with distance flown and flight duration. The most favorable temperature for long dispersion was 26 °C, with suboptimal temperatures in the range of 32–37 °C and the least favorable temperatures at 40 and 43 °C. In conclusion, D. citri is able to fly in a broad range of temperatures and efficiently fly in high and low humidity. However, temperatures above 40 °C, similar to those experienced in semi-arid environments like Southern California or Arizona, are detrimental for its flight capacity.

How Far Can Rhynchophorus palmarum (Coleoptera: Curculionidae) Fly?

The palm weevil, Rhynchophorus palmarum (L.), was first recorded in San Diego County, CA in 2011 and breeding populations were recovered from infested Canary Islands date palms, Phoenix canariensis, in San Ysidro, San Diego County, in 2015. This palm pest presents a significant threat to California's edible date industry as Phoenix dactylifera is a recorded host for this weevil. The flight capabilities of R. palmarum are unknown which limits understanding of rates of natural dispersal. In response to this knowledge deficit, 24-h flight mill trials were conducted with field-collected male and female weevils. A total of 87 weevils (49 females and 38 males) were used in experiments, ~6% failed to fly >1 km in 24 h and were excluded from analyses. Of those 82 weevils flying >1 km in 24 h, the average distance flown by males and females was ~41 and ~53 km, respectively. Approximately 10% of females flew >100 km in 24 h, with two (~4%) females flying >140 km. The maximum recorded distance flown by a male weevil was 95 km. Flight activity was predominantly diurnal and flying weevils exhibited an average weight loss of ~18% while non-flying control weevils lost ~13% body weight in 24 h. The combined flight distances for male and female weevils exhibited a heavy-tailed platykurtic distribution. Flight mill data for R. palmarum are compared to similarly collected flight mill data for two other species of invasive palm weevil, Rhynchophorus ferrugineus (Olivier) and Rhynchophorus vulneratus (Panzer).

Observations on Euchloe olympia (W. H. Edwards) (Pieridae) in a Central Illinois Sand Prairie.

Euchloe olympia was studied in a sand prairie in central Illinois each year for a period of five years to monitor behavior. Adults were followed by groups of observers; groups tracked the type of flowers utilized for nectar, the flight time between visits to plants or the substrate, the distance flown between each plant or substrate, and any additional behaviors (such as oviposition and courtships). We made over 1300 observations of 53 butterflies. Individuals were found to differ significantly in various aspects of their behavior; including nectar source, average time nectaring and flight activity. The main larval food plant was found to be Lepidium virginicum, while the main adult nectar source was found to be Nuttallanthus canadensis. Individuals consistently showed considerable constancy in the flowers they visited.

The Carbon Footprint of Volunteer Tourism

Abstract Tourism is growing at a fast rate and so is its carbon footprint. Alongside conventional tourism, a new form of tourism, so-called voluntourism, has emerged. The discussion on voluntourism in the existing literature has hereby mainly centred around its positive impacts on the health and education of communities and the local environment in developing countries. Nevertheless, little attention has been drawn to its climate impacts. This study set out to investigate the carbon footprint of voluntourism. The data were collected at a local non-governmental organisation (NGO) in India working with voluntourists. Both the carbon footprint of the stay in India and that from the round trip by air were taken into consideration. The results showed that although the carbon footprint of voluntourists during their stay is comparable with that of locals, the flight significantly contributes to the carbon footprint of voluntourism. Depending on the distance flown and the length of the stay, the average share of the carbon footprint stemming from the flight can be between 83% and 96%. The article concludes that faraway destinations and short stays should be avoided; otherwise voluntourism might cause more harm than good. On the basis of the findings, this article provides recommendations for policymakers and further research.

Trajectory optimization in daily operations

This study embeds multi-criteria optimized trajectories in today’s procedures of flight planning, preparing and operations. Therefore, European air traffic procedures are substantiated by a review of today’s regulative provisions and possibilities of intended deviations from filed flight plans initiated by both air traffic control and flight crew. As a reference for future flight planning, we modeled and described multi-criteria optimized trajectories. Thereupon, we developed an efficient and reliable algorithm for the adaption of waypoint-less optimized trajectories to the current navaid infrastructure. This method aims at increasing in airline efficiency in daily operations. For validation purposes, an actual flight plan has been calculated using the commercial flight-planning tool JetPlan.com by Jeppesen and is compared to our adapted trajectories. The comparison allows for the quantification of the benefits of our adapted flight paths against the restrictions of today’s flight planning. Here, we used a performance metric, considering distance flown, time of flight and fuel burn.

M8 PROXY-PHENOTYPING OF ANXIETY AND DEPRESSION USING SELF-REPORTED MEDICATION DATA

This chapter proposes an overview of the reasons for flying that alternates between a focus on empirical material and methodological issues. Information gathered shows that leisure—defined here as holiday and visiting friend and relatives—is the dominant purpose of flying. This puts the alleged dominance of business travel into perspective, at least in terms of number of passengers carried. However, common statistics mask the fact that there are often multiple, combined reasons for flying. In addition, flying purposes vary across places, subject to their attributes (including social and demographic profiles, economic patterns, and tourist amenities) and institutional aspects. They also change over time, both short term (seasonal cycles) and longer term (structural changes). Avenues for future research include investigating travel in developing countries, domestic travel, and travel purpose, weighted by distance flown and/or by revenues generated for the airline business.

A method for estimating flight paths missing data

Air-traffic optimization is an essential part of airspace operation reengineering, as the number of flights and the usage of routes increase in the world. The NextGen and SESAR projects are important initiatives that allow for more scalability and safety in air-traffic. One element of these projects is the Automatic Dependent Surveillance-Broadcast (ADS-B) system which allows airplanes to share their position and speed. The ADS-B antennas’ coverage is somewhat limited in less economically developed and oceanic areas, resulting in a lack of flight path data. This paper proposes a method based on artificial neural networks (ANN), interpolation and average computation to fill flight path data partially tracked by ADS-B antennas. While other methods are focused on one or two dimensions of the flight path, this work is focused on infilling the 4-dimensions present in the ADS-B data (latitude, longitude, altitude and ground speed). This work is useful in analyzing performance of historical flights related to limited coverage areas or in predicting flight path in air-traffic management systems (ATMs). The comparison between the real and estimated trajectories in a set of 517 flights has shown accuracy superior to 92% for the metrics distance flown, estimated burned fuel, and trajectory correlation.

Effects of Wind, Temperature, and Barometric Pressure on Asian Citrus Psyllid (Hemiptera: Liviidae) flight behavior.

The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae), is the vector of the bacterium responsible for huanglongbing, a deadly plant disease affecting citrus worldwide. We investigated the effects of wind direction and speed on flight duration and direction of D. citri, as well as the effects of temperature and barometric pressure on sustained flight duration of D. citri. Experiments were performed with laboratory flight mills and wind tunnels. Flight activity of D. citri increased with increasing temperature. Of the few insects that flew at 18°C, most performed short duration flights (<60 s). When exposed to temperatures between 21 and 28°C, D. citri performed long duration flights (>60 s). In addition, the distance covered increased with temperature. Interestingly, males were more sensitive to cold temperature and flew significantly shorter distances than females at 21 and 25°C. Barometric pressure recorded before and during the flight mill experiment suggested that decreasing pressure reduced distance flown by D. citri. Flight direction was strongly influenced by wind. In wind tunnel experiments where psyllids were challenged to reach citrus leaf flush positioned either downwind or upwind, most D. citri moved downwind when exposed to continuous airflow. In a subsequent experiment, we challenged psyllids to pulsed wind blowing at higher speeds. In this case, most psyllids progressed upwind, suggesting upwind movement by psyllids during pauses within pulsed airflow. Collectively, the results indicate that D. citri are able to modify their flight behavior in response to abiotic factors.

Impacts of nectar robbing on the foraging ecology of a territorial hummingbird

While the effects of nectar robbing on plants are relatively well-studied, its impacts from the perspective of the pollinators of robbed plants is not. Numerous studies do consider the impacts of robbing on pollinator visitation to robbed plants, but rarely do they focus on its scaled-up impacts on individual pollinator behavior. We used radio telemetry to track the spatial and behavioral responses of the territorial hummingbird Aglaeactis cupripennis to experimental nectar robbing over a period of several days. Simulated nectar robbing impacted foraging behavior by increasing territory area, distance flown, and reliance on novel food resources, especially small-bodied flying insects. We did not observe any impact on the amount of time individuals spent foraging, nor did we observe territory abandonment. These findings indicate that nectar robbing may impose a significant energetic cost on pollinators via increased flight distances and shifts towards potentially less profitable food resources, and demonstrate the importance of quantifying the indirect effects of nectar robbing on pollinators in addition to plants.

The aerodynamics of flight in an insect flight-mill.

Predicting the dispersal of pest insects is important for pest management schemes. Flight-mills provide a simple way to evaluate the flight potential of insects, but there are several complications in relating tethered-flight to natural flight. We used high-speed video to evaluate the effect of flight-mill design on flight of the red palm weevil (Rynchophorous ferruginneus) in four variants of a flight-mill. Two variants had the rotating radial arm pivoted on the main shaft of the rotation axis, allowing freedom to elevate the arm as the insect applied lift force. Two other variants had the pivot point fixed, restricting the radial arm to horizontal motion. Beetles were tethered with their lateral axis horizontal or rotated by 40°, as in a banked turn. Flight-mill type did not affect flight speed or wing-beat frequency, but did affect flapping kinematics. The wingtip internal to the circular trajectory was always moved faster relative to air, suggesting that the beetles were attempting to steer in the opposite direction to the curved trajectory forced by the flight-mill. However, banked beetles had lower flapping asymmetry, generated higher lift forces and lost more of their body mass per time and distance flown during prolonged flight compared to beetles flying level. The results indicate, that flapping asymmetry and low lift can be rectified by tethering the beetle in a banked orientation, but the flight still does not correspond directly to free-flight. This should be recognized and taken into account when designing flight-mills and interoperating their data.

Flight performance of Monochamus sartor and Monochamus sutor, potential vectors of the pine wood nematode

Abstract Flight performance of Monochamus sartor and Monochamus sutor, two potential vectors of the pine wood nematode, Bursaphelenchus xylophilus was evaluated in laboratory flight mill tests. Beetles emerging from logs infested in the laboratory and incubated under outdoor conditions as well as field collected beetles were used. The maximum distance flown by M. sartor in a single flight was 3,136.7 m. Mean distances (per beetle) per flight ranged from 694.6 m in females to 872.5 m in males for M. sartor. In 75% of all individual flights M. sartor flew less than 1 km; only 3.7% flew distances longer than 2 km. The mean cumulative distance travelled by M. sartor beetles throughout their lifespan was 7.5 km. The smaller M. sutor beetles flew faster and longer distances. The maximum distance per flight was 5,556.5 m; mean distances ranged from 1,653.6 m in females to 1178.3 m in males. The number of available laboratory reared beetles was too low for quantification of lifetime flight capacity for M. sutor. The findings are compared to published data from Monochamus galloprovincialis recorded on the same type of flight mill as well as to field data from mark-release-recapture studies. The high flight capacity of Monochamus beetles illustrates the importance of considering dispersal of the vectors when planning control measures against the pine wood nematode.

A mitigation strategy for commercial aviation impact on NOx‐related O3 change

AbstractAn operational mitigation strategy for commercial aircraft impact on atmospheric composition, referred to as the turboprop replacement strategy (TRS), is described in this paper. The global air traffic between 2005 and 2011 was modeled with the TRS in which turbofan powered aircraft were replaced with nine chosen turboprop powered aircraft on all routes up to 1700 nautical miles (NM) in range. The results of this TRS double the global number of departures, as well as global mission distance, while global mission time grows by nearly a factor of 3. However, the global mission fuel and the emissions of aviation CO2, H2O, and SOx remain approximately unchanged, and the total global aviation CO, hydrocarbons (HC), and NOx emissions are reduced by 79%, 21%, and 11% on average between 2005 and 2011. The TRS lowers the global mean cruise altitude of flights up to 1700 NM by ~2.7 km which leads to a significant decrease in global mission fuel burn, mission time, distance flown, and the aircraft emissions of CO2, CO, H2O, NOx, SOx, and HC above 9.2 km. The replacement of turbofans with turboprops in regional fleets on a global scale leads to an overall reduction in levels of tropospheric O3 at the current estimated mean cruise altitude near the tropopause where the radiative forcing of O3 is strongest. Further, the replacement strategy results in a reduction of ground‐level aviation CO and NOx emissions by 33 and 29%, respectively, between 2005 and 2011.

A Simple Flight Mill for the Study of Tethered Flight in Insects.

Flight in insects can be long-range migratory flights, intermediate-range dispersal flights, or short-range host-seeking flights. Previous studies have shown that flight mills are valuable tools for the experimental study of insect flight behavior, allowing researchers to examine how factors such as age, host plants, or population source can influence an insects' propensity to disperse. Flight mills allow researchers to measure components of flight such as speed and distance flown. Lack of detailed information about how to build such a device can make their construction appear to be prohibitively complex. We present a simple and relatively inexpensive flight mill for the study of tethered flight in insects. Experimental insects can be tethered with non-toxic adhesives and revolve around an axis by means of a very low friction magnetic bearing. The mill is designed for the study of flight in controlled conditions as it can be used inside an incubator or environmental chamber. The strongest points are the very simple electronic circuitry, the design that allows sixteen insects to fly simultaneously allowing the collection and analysis of a large number of samples in a short time and the potential to use the device in a very limited workspace. This design is extremely flexible, and we have adjusted the mill to accommodate different species of insects of various sizes.

A Simple Flight Mill for the Study of Tethered Flight in Insects

Flight in insects can be long-range migratory flights, intermediate-range dispersal flights, or short-range host-seeking flights. Previous studies have shown that flight mills are valuable tools for the experimental study of insect flight behavior, allowing researchers to examine how factors such as age, host plants, or population source can influence an insects' propensity to disperse. Flight mills allow researchers to measure components of flight such as speed and distance flown. Lack of detailed information about how to build such a device can make their construction appear to be prohibitively complex. We present a simple and relatively inexpensive flight mill for the study of tethered flight in insects. Experimental insects can be tethered with non-toxic adhesives and revolve around an axis by means of a very low friction magnetic bearing. The mill is designed for the study of flight in controlled conditions as it can be used inside an incubator or environmental chamber. The strongest points are the very simple electronic circuitry, the design that allows sixteen insects to fly simultaneously allowing the collection and analysis of a large number of samples in a short time and the potential to use the device in a very limited workspace. This design is extremely flexible, and we have adjusted the mill to accommodate different species of insects of various sizes.

Maximizing strike aircraft planning efficiency for a given class of ground targets

Strike planning is one of the fundamental tasks of an advanced Air Force and involves the assignment of strike aircraft to ground targets with a maximum level of efficiency. Therefore, planning an optimal strike based on the preferences of the decision maker is crucial. The efficiency of the strike plan in this paper implies attacking the maximum number of targets while considering target priority and the desired level of damage on each target. The other objective is to minimize the cost of the strike plan. This paper develops a methodology that maximizes the efficiency of the strike plan. Given this efficiency, the aircraft and weapon costs plus the distance flown is then minimized. The methodology also considers the capacities for different types of aircraft and weapons at each aircraft base to avoid assigning aircraft to targets from a base where there are insufficient resources to do so. Computational results are presented that analyze the sensitivity of the model solution times to solver optimality tolerance and aircraft and weapon capacities. Results also suggest substantial cost savings are possible while still maintaining the effectiveness of the strike package.

On the application of light weight materials to improve aircraft fuel burn – reduce weight or improve aerodynamic efficiency?

AbstractAn analysis, based upon exact relations and previously published approximate relations, is presented. It describes the connection between changes in aircraft weight and changes in the energy to revenue work ratio (ETRW), which, for a given aircraft on a given route, correspond to changes in trip fuel burn. This is used to establish the link between weight saving and fuel burn improvement at both the total aircraft and the component levels. The analysis is then extended to address the impact of trading weight savings anywhere on the aircraft for increased wing aspect ratio, whilst the aircraft total weight remains the same. It is shown that, for flights in excess of about 350 km, if saving fuel is the objective and provided that all the aerodynamic design and airworthiness requirements can be met, it is better to trade weight saving for increased aspect ratio. In general, the ratio of fuel burn reductions for traded to non-traded weight varies with aircraft size, design range, distance flown and payload carried, with the maximum values, for typical operational payloads, ranging from 2•8, for the smaller aircraft, to 2•2 for the largest aircraft, with medium haul operations deriving the largest benefit. It is estimated that, over the past 50 years, about 10% of the operational empty weight has been traded for increased aspect ratio, giving close to a 20% improvement in ETRW. Finally, estimates are produced for the impact of weight reduction and traded weight reduction on the fuel burn for the current global feet.