Flight Tunnel Research Articles

Identification of aircraft longitudinal aerodynamic parameters using an online corrective test for wind tunnel virtual flight

The identification of aerodynamic parameters is accomplished through the test data of the dynamic movement of scaled aircraft models flying dynamically in wind tunnel, which can realize the accurate acquisition of the aerodynamic model of the aircraft in the preliminary stage for aircraft design, and it is of great significance for improving the efficiency of aircraft design. However, the translational motion of the test model in the wind tunnel virtual flight is subject to constraints that result in distinct flight dynamics compared to free flight. These constraints have implications for the accuracy of aerodynamic derivatives obtained through the identification of wind tunnel test data. With this issue in mind, the research studies the differences in longitudinal dynamic characteristics between unconstrained free flight and wind tunnel virtual flight, and innovatively proposes an online correction test based wind tunnel virtual flight test technique. The longitudinal trajectory and velocity changes of the model are solved online by the aerodynamic forces measured during the test, and then the coupled relationship between aircraft translation and rotation is used to correct the model’s pitch attitude motion online. For the first time, the problem of solving the data approximation for free flight has been solved, eliminating the difference between the dynamics of wind tunnel virtual flight and free flight, and improving the accuracy of the aerodynamic derivative identification results. The experiment’s findings show that accurate aerodynamic derivatives can be identified based on the online correction test data, and the observed behaviour of the identified motion model has similarities to that of the free flight motion model.

An experimental array setup to study the integration of biosonar and maneuvering flight in bats

Understanding biosonar-based flight control in bats remains a challenge for fundamental bioacoustics and holds promise for engineered flight-control systems, especially for highly maneuverable drones. To accomplish this, detailed data on bat flight is required that captures the variability across flight situations, individuals, and species. Hence, a flight tunnel has been constructed that provides enough space for natural flight maneuvers. Reconstructing the detailed geometry of freely maneuvering bats requires capturing a flying bat from many different angles to ensure freedom from occlusions. Ideally, this would also be done without placing artificial markers on the bat. Hence, a flight tunnel has been instrumented with arrays of 50 high-speed video cameras and 28 ultrasonic microphones that were all integrated within a modular canvas setup. The optical properties of each camera have been determined from multiple images taken of a panel with a calibration grid seen from different orientations. The spatial relationship between the cameras was estimated based on a large set of images containing random points created with an LED. Reconstructing the 3D geometries of the bats from large numbers of high-speed video frames requires an automated method due to the problem's complexity. To this end, deep-learning methods are currently under development.

Using a biomimetic sonar bat robot to explore the sensory world of bats in the field and in the laboratory

Bat species such as those belonging to the families of horseshoe and Old World leaf-nosed bats make their navigation decisions based on echoes that are often received from dense vegetation. To gain an understanding of how these animals accomplish navigation based on such complicated clutter echoes, a biomimetic sonar system that replicates the auditory periphery of bats has been used as synthetic observer to probe the sensory stimulus ensemble of the bats in a flight tunnel as well as in the field. Both laboratory and field experiments were carried out in Brunei on the island of Borneo. For the flight tunnel, the biomimetic sonar robot has been used to record a large number of pulse and echo pairs in conjunction with an array consisting of 28 ultrasonic microphones. In this experiment, the sonar head was positioned at points spaced on a 3d grid that covers the tunnel's volume. This data set will be used to train a deep neural network to predict the inputs to the ears of a bat maneuvering in the tunnel. In the field experiments, the sonar head was carried off road in various tropical-forest habitats to record echo samples in conjunction with precise GPS location references.

Hummingbirds use distinct control strategies for forward and hovering flight.

The detection of optic flow is important for generating optomotor responses to mediate retinal image stabilization, and it can also be used during ongoing locomotion for centring and velocity control. Previous work in hummingbirds has separately examined the roles of optic flow during hovering and when centring through a narrow passage during forward flight. To develop a hypothesis for the visual control of forward flight velocity, we examined the behaviour of hummingbirds in a flight tunnel where optic flow could be systematically manipulated. In all treatments, the animals exhibited periods of forward flight interspersed with bouts of spontaneous hovering. Hummingbirds flew fastest when they had a reliable signal of optic flow. All optic flow manipulations caused slower flight, suggesting that hummingbirds had an expected optic flow magnitude that was disrupted. In addition, upward and downward optic flow drove optomotor responses for maintaining altitude during forward flight. When hummingbirds made voluntary transitions to hovering, optomotor responses were observed to all directions. Collectively, these results are consistent with hummingbirds controlling flight speed via mechanisms that use an internal forward model to predict expected optic flow whereas flight altitude and hovering position are controlled more directly by sensory feedback from the environment.

Biodiversity and big data to investigate the link between biosonar sensing and flight control in bats

Any animal with dexterous mobility in complex natural environments needs powerful systems for sensing and mobility that also have to be well-integrated with each other. Echolocating bats that hunt in dense vegetation rely on biosonar integrated with flapping flight to accomplish this. The low-dimensional nature of the biosonar inputs together with the complexity of the bats' flight apparatus make this coupling a fundamental scientific challenge. To understand how bats can control the many degrees of freedom of their wings based on external information that is conveyed by only two one-dimensional echo trains, a flight tunnel has been instrumented with synchronized high-speed video cameras and ultrasonic microphones. The array recordings can provide data volumes that are large enough to enable deep-learning analyses of the biosonar echoes and the flight kinematics. These analyses will be applied to reducing the dimensionality of ultrasonic inputs, the kinematic outputs, and discovering the relationship between the essential dimensions of biosonar and flight. The tunnel has been installed on the island of Borneo to take advantage of the local bat biodiversity as a source of variability that can be exploited in a comparative approach to identify functional traits that are essential to sensorimotor integration in echolocating bats.

Going against the flow: bumblebees prefer to fly upwind and display more variable kinematics when flying downwind.

Foraging insects fly over long distances through complex aerial environments, and many can maintain constant ground speeds in wind, allowing them to gauge flight distance. Although insects encounter winds from all directions in the wild, most lab-based studies have employed still air or headwinds (i.e. upwind flight); additionally, insects are typically compelled to fly in a single, fixed environment, so we know little about their preferences for different flight conditions. We used automated video collection and analysis methods and a two-choice flight tunnel paradigm to examine thousands of foraging flights performed by hundreds of bumblebees flying upwind and downwind. In contrast to the preference for flying with a tailwind (i.e. downwind) displayed by migrating insects, we found that bees prefer to fly upwind. Bees maintained constant ground speeds when flying upwind or downwind in flow velocities from 0 to 2 m s-1 by adjusting their body angle, pitching down to raise their air speed above flow velocity when flying upwind, and pitching up to slow down to negative air speeds (flying backwards relative to the flow) when flying downwind. Bees flying downwind displayed higher variability in body angle, air speed and ground speed. Taken together, bees' preference for upwind flight and their increased kinematic variability when flying downwind suggest that tailwinds may impose a significant, underexplored flight challenge to bees. Our study demonstrates the types of questions that can be addressed with newer approaches to biomechanics research; by allowing bees to choose the conditions they prefer to traverse and automating filming and analysis to examine massive amounts of data, we were able to identify significant patterns emerging from variable locomotory behaviors, and gain valuable insight into the biomechanics of flight in natural environments.

Long-duration wind tunnel flights reveal exponential declines in protein catabolism over time in short- and long-distance migratory warblers

During migration, long-distance migratory songbirds may fly nonstop for days, whereas shorter-distance migrants complete flights of 6 to 10 h. Fat is the primary fuel source, but protein is also assumed to provide a low, consistent amount of energy for flight. However, little is known about how the use of these fuel sources differs among bird species and in response to flight duration. Current models predict that birds can fly until fat stores are exhausted, with little consideration of protein's limits on flight range or duration. We captured two related migratory species-ultra long-distance blackpoll warblers (Setophaga striata) and short-distance yellow-rumped warblers (Setophaga coronata)-during fall migration and flew them in a wind tunnel to examine differences in energy expenditure, overall fuel use, and fuel mixture. We measured fat and fat-free body mass before and after flight using quantitative magnetic resonance and calculated energy expenditure from body composition changes and doubly labeled water. Three blackpolls flew voluntarily for up to 28 h-the longest wind tunnel flight to date-and ended flights with substantial fat reserves but concave flight muscle, indicating that protein loss, rather than fat, may actually limit flight duration. Interestingly, while blackpolls had significantly lower mass-specific metabolic power in flight than that of yellow-rumped warblers and fuel use was remarkably similar in both species, with consistent fat use but exceptionally high rates of protein loss at the start of flight that declined exponentially over time. This suggests that protein may be a critical, dynamic, and often overlooked fuel for long-distance migratory birds.

Plasma T3 and T4 Hormone Levels as Reference Values in Rehabilitated Common Buzzard (Buteo buteo), Long-Legged Buzzard (Buteo rufinus) and Golden Eagle (Aquila chrysaetos)

Applying appropriate criteria for raptors at rehabilitation stages including release and post release determines how healthy the animal can survive in its natural habitat for any length of time. In determining release criteria, clinical examinations of animals as well as clinical data should be evaluated. In this study, plasma T3 and T4 levels of 16 Common Buzzard (Buteo buteo), 7 Long-legged Buzzard (Buteo rufinus) and 7 Golden Eagles (Aquila chrysaetos) were determined at Kafkas University/ Kafkas Wildlife Conservation, Rescue, Rehabilitation Practice and Research Center between 2016-2018. All raptors were kept at the rehabilitation center for 1-3 months in bird care rooms and flight tunnels specially arranged for each species. Rehabilitated birds blood were collected before released to wild. Plasma T3 and T4 hormone levels were analysed and determined in raptors that considered suitable for release. Although small differences were detected between T3 and T4 values as a result of the analysis, no statistical difference was found. These small differences in values may be due to the metabolic responses and environmental conditions of each raptor. As a result, these plasma thyroid hormone levels in rehabilitated raptors can be accepted as reference values.

High-carb diet gives migrating locusts a head start

Some feats of migration are truly astounding. Arctic terns journey pole to pole each year, the great-great-great-grandchildren of the monarch butterflies that embarked initially in autumn return to their northern homes after their ∼5000 km odyssey and some desert locusts have even crossed the Atlantic, reaching the Caribbean and South America from North Africa. Stav Talal and colleagues from Arizona State University (ASU) explain that most creatures fuel these epic voyages with carbohydrate and energy-rich lipids, often obtained directly from an animal's diet. However, locusts, which tend to feast on vegetation, have to supply their own lipid fuels created from the carbohydrates in their diet and little was known about the impact that a locust's diet might have on its ability to sustain a long flight. In 2017, Arianne Cease, Jon Harrison and ASU colleagues discovered that Mongolian locusts (Oedaleus asiaticus) raised on a high-carb diet flew longer than locusts fed a low-carb diet. But how well would the true champions of the locust world, the migratory locust (Locusta migratoria), fly when they too were provided with a high-carb diet?‘We reared the locusts in crowded cages from hatchlings, sometimes with more than 1000 locusts in one cage, to produce the migratory form of the insects’, says Talal, who, with Geoffrey Osgood (ASU), fed the locusts one of three separate diets – a high-carb, low-protein diet; a medium-carb, medium-protein diet; and a low-carb, high-protein diet – before building locust-sized flight tunnels to measure the insects’ flight endurance. Filming more than 100 locusts, the team recorded that the locusts on the high-carb diet had the most stamina, while the locusts that had been reared on the low-carb diet were much weaker. ‘Six out of 34 locusts fed the high-carb diet flew continuously for 12 h, whereas only one locust out of 35 from the medium-carb diet flew for 12 h’ says Shivam Parmar (ASU), adding that none of the locusts on the low-carb diet managed to fly for the full 12 h. But how had the diets affected the locusts’ body composition and how did that change after their epic flights?Sure enough, when Parmar and Talal compared the locusts, the insects that had dined on the high-carb food were carrying the most lipid, accounting for up to 37% of their body mass, before embarking on their day-long flights. But by the time they had completed their marathons, all of the insects, regardless of diet, had used up a significant proportion of their lipid stores. However, even though the low-carb diet locusts were still carrying 75 mg of lipid – which is sufficient to keep a locust airborne for a full 12 h – they stopped flying after just 5.5 h. So why were they giving up so soon?The team suspects that several factors could be responsible for the low-carb locusts giving up early. They suggest that the locusts may simply be guarding their carbohydrate reserves, terminating a flight when their carb levels fall too low, or a high-carb diet might somehow protect flying insects from the damaging effects of oxygen that they use to power their flight. Another possibility is that the locusts fed a low-carb diet dry out faster when flying, or their muscle composition might be subtly different, limiting their endurance.Whatever the reason, it is clear that a high-carb diet is essential for locusts intent on a high endurance flight, unless they get some tailwind assistance, which probably accounts for the intrepid transatlantic voyage of the locusts that made it all the way to South America.

Quantifying the Aerodynamic Power Required for Flight and Testing for Adaptive Wind Drift in Passion-Vine Butterflies Heliconius sara (Lepidoptera: Nymphalidae)

Although theoretical work on optimal migration has been largely restricted to birds, relevant free-flight data are now becoming available for migratory insects. Here we report, for the first time in passion-vine butterflies, that Heliconius sara migrates directionally. To test optimal migration models for insects, we quantified the aerodynamic power curve for free-flying H. sara as they migrated across the Panama Canal. Using synchronized stereo-images from high-speed video cameras, we reconstructed three-dimensional flight kinematics of H. sara migrating naturally across the Panama Canal. We also reconstructed flight kinematics from a single-camera view of butterflies flying through a flight tunnel. We calculated the power requirements for flight for H. sara over a range of flight velocities. The relationship between aerodynamic power and velocity was "J"-shaped across the measured velocities with a minimum power velocity of 0.9 m/s and a maximum range velocity of 2.25 m/s. Migrating H. sara did not compensate for crosswind drift. Changes in airspeed with tailwind drift were consistent with the null hypothesis that H. sara did not compensate for tailwind drift, but they were also not significantly different from those predicted to maximize the migratory range of the insects.

Flight-to-Wind-Tunnel Correlation Study using JAXA’s Flying Test Bed “Hisho”

Predicting aircraft flight performance using ground tests is important for development but difficult, and flight-to-wind-tunnel correlation methods have been developed and improved over many years. This paper examines the flight-to-wind-tunnel correlation of the aerodynamic characteristics of the Japan Aerospace Exploration Agency’s (JAXA) “Hisho” Flying Test Bed by applying typical methods to flight test data. It was found that the minimum drag coefficient of a business jet geometry test model follows the gradient of the Schoenherr equation well for forced turbulent flows. After that, the reference condition for the correlation was set, but discrepancies in the lift and drag coefficients remained between the flight and wind tunnel tests. A preliminary study identified force differences parallel to the axis of the engine nacelle as being caused by spillage drag due to the difference in the capture area ratio (CAR) between the flight and wind tunnel tests. However, the test data were insufficient to reasonably attribute the difference in the normal force component to lift yielded by the engine nacelle. This was due to the fact that the flight test parameters showed an interdependency and the effects of relevant parameters were not fully investigated in wind tunnel tests.

Numerical Simulation of Unsteady Fluid Parameters for Maglev Flight Wind Tunnel Design

The maglev flight tunnel is a novel conceptual aerodynamics test facility, in which the complicated aerodynamic characteristics caused by the high-speed translation of a moving model in a long, straight, closed tunnel, and wave propagation and aero-structure single-way coupling problems can be investigated. The unsteady characteristics originating from a high-speed model in the maglev flight tunnel were investigated and evaluated with regard to aero–structure coupling. The new conservation element and solution element method was used to solve the 3-D compressible fluid surrounding a moving model in a tunnel, and the variations in the aerodynamic parameters, wave propagation characteristics, and pressure distribution in the tunnel were obtained. The results provide support for key technical problems, such as a wave-absorbing construction design of the maglev flight wind tunnel.

The oviposition cue indole inhibits animal host attraction in Aedes aegypti (Diptera: Culicidae) mosquitoes

BackgroundMosquitoes are responsible for disease transmission worldwide. They possess the ability to discriminate between different ecological resources, including nectar sources, animal hosts and oviposition sites, a feature mediated by their olfactory system. Insect repellents, such as N,N-diethyl-meta-toluamide (also called DEET), have been shown to activate and inhibit mosquito odorant receptors, resulting in behavioral modulation. This and other repellents currently available for personal protection against mosquitoes are topically applied to the skin and operate at a short range. In our search for potential long-range inhibitors of attractants to human hosts, we have hypothesized that the shared chemical similarities between indole and DEET may confer the former with the ability to block odorant receptor function and inhibit human host attraction in a similar way as DEET.MethodsWe used the two-electrode voltage clamp system to assay Xenopus laevis oocytes as a platform to compare the pharmacological effect of commercially available insect repellents and indole on the Aedes aegypti (R)-1-octen-3-ol receptor, OR8, a receptor involved in the decision-making of female mosquitoes to identify human hosts. We also conducted arm-in-a-cage and wind-tunnel bioassays to explore the effect of indole on human host-seeking female Aedes aegypti mosquitoes.ResultsOur results demonstrate that indole inhibited the Aedes aegypti (R)-1-octen-3-ol receptor OR8. In our arm-in-a-cage assay, 1 M of DEET reduced mosquito visits on average by 69.3% while the same indole concentration achieved 97.8% inhibition. This effect of indole on flight visits was dose-dependent and disappeared at 1 μM. In the flight tunnel, indole elicited on average 27.5% lower speed, 42.3% lower upwind velocity and 30.4% higher tortuosity compared to the control.ConclusionsIndole significantly inhibits OR8 activation by (R)-1-octen-3-ol, mosquito visits to a human hand and long-range human host-seeking. The volatility of indole may be leveraged to develop a novel insect repellent in the context of personal mosquito protection.Graphical abstract

An experimental setup for decoupling optical invariants in honeybees’ altitude control

Bees outperform pilots in navigational tasks, despite having 100,000 times fewer neurons. It is commonly accepted in the literature that optic flow is a key parameter used by flying insects to control their altitude. The ambition of the present work was to design an innovative experimental setup that would make it possible to determine whether bees could rely simultaneously on several optical invariants, as pilots do. We designed a flight tunnel to enable manipulation of an optical invariant, the Splay Angle Rate of Change (SARC) and the restriction of the Optical Speed Rate of Change (OSRC) in the optic flow. It allows us to determine if bees use the SARC to control their altitude and to identify the integration process combining these two optical invariants. Access to the OSRC can be restricted by using different textures. The SARC can be biased thanks to motorized rods. This device allows to record bees’ trajectories in different visual configurations, including impoverished conditions and conditions containing contradictory information. The comparative analysis of the recorded trajectories provides first time evidence of SARC use in a ground-following task by a non–human animal. This new tunnel allows a precise experimental control of the visual environment in ecological experimental conditions. Therefore, it could pave the way for a new type of ecologically based studies examining the simultaneous use of several information sources for navigation by flying insects.

Spatiotemporal dynamics of biosonar in navigating Bornean Rhinolophid and Hipposiderid bats

To investigate the active sensing strategies used by echolocating bats of the genera Rhinolophus and Hipposideros, we have constructed a 9-meter long flight tunnel, which incorporates an array of 32 ultrasonic microphones distributed throughout the tunnel. Rhinolophus and Hipposideros are of special interest because of their highly flexible biosonar system; these bats emit pulses from their nasal cavities, using complex noseleaf structures to quickly and precisely alter the beam-form and direction of emissions. Additionally, each species utilizes a unique combination of constant-frequency (CF) and frequency-modulated (FM) ultrasonic signals with varying durations, repetition rates, and frequencies. We plan to trap several species of wild Bornean bats of these genera and fly individual bats through the tunnel; a time-of-arrival algorithm will be used to localize the position of each bat at the time of each biosonar pulse emission, and an amplitude-comparison method to measure the horizontal and vertical direction of each emission from the bat’s noseleaf. We will also incorporate relatively simple foliage obstacles into the tunnel; this will create complex acoustic clutter and allow us to determine how bats of different species adjust their biosonar sampling strategies in order to navigate around novel obstacles in a cluttered environment.

Investigating the integration of biosonar sensing and flight control in bats on Borneo

Many bat species rely on biosonar as their primary source of sensory information about their environments. Species that are able to navigate amid dense vegetation use this biosonar information to guide highly dexterous flight maneuvers. Understanding the connection between biosonar inputs and flight outputs poses a challenge, because the flight apparatus of bats has the most degrees of freedom of any flight system—whether natural or man-made. At the same time, the biosonar inputs consist of just two one-dimensional acoustic time signals (i.e., echoes received at the two ears). Due to the complexity and large variability in the echoes and the flight maneuvers of bats, understanding the input-output relationships requires the ability to collect large amounts of quantitative data on the acoustics and the flight kinematics. In addition, comparing different bat species could offer a window into the principles behind the evolutionary co-adaptation of biosonar and flight. To accomplish this, a cylindrical flight tunnel that integrates synchronized arrays of 50 high-speed video cameras and 32 ultrasonic microphones has been set up on the island of Borneo. This instrument is complemented by a set of custom deep-learning techniques that can handle the large amounts of data that are being produced.

A comparative study of a bioinspired flapping bat robot and Bornean bats

Effectively characterizing the significance of bioinspired design for the advancement of robotics technology is a complex endeavor. Here, a direct comparative analysis was conducted to examine the differences between a bioinspired bat robot and bats. The unique maneuvering and biosonar capabilities of bats have long been recognized as a source of technical inspiration. However, the capabilities of bats in these areas still far exceed those of current robotics models. To evaluate these differences, we have been preparing to fly rhinolophid/hipposiderid bats and a bat-robot prototype through a flight tunnel instrumented with arrays of 50 high-speed cameras and 32 ultrasonic microphones. Using this approach, kinematic and acoustic data can be compiled to enable a thorough comparison of the bats and the robot. This data can support a quantitative analysis of key characteristics such as wing cycle, size ratios, lift and thrust capacity, as well as maximum carrying capacity. Based on insight from this data, strategic design iterations can be carried out to more accurately mimic bat flight with considerations for incorporation of biosonar-inpsired technology into the design. By continuing this process, an in-depth understanding of the bioinspired design approach, implementation, and impact to the design process can be achieved.

Icing on Full-Scale Swept Wings in Flight and Icing Wind Tunnel

Inflight ice accretion on aircraft wings has been critically important for development and certification of transport category aircraft. With recent efforts toward certification by analysis, it is becoming increasingly important to characterize ice accretions in icing wind tunnels, the primary source of validation data for higher-fidelity three-dimensional ice shape analysis codes to be used in aircraft certification, in comparison with those in natural icing environments. In this study, a series of natural icing flight tests and icing wind tunnel tests were conducted on a transport category aircraft. The results were compared at similar test conditions on protected and unprotected surfaces of swept wings and empennage. For unprotected surfaces, both tests resulted in scallop ice, with natural icing flight test resulting in significantly smaller ice accretions. For protected surfaces, runback ice was formed on the lower wing surface in both tests, with natural icing flight test resulting in significantly less and sparser runback ice. Differences in scallop ice structures, limitations of icing wind tunnels, and scaling methods are considered the potential contributing factors to the differences. The results indicate a need for further studies on case-to-case comparison of ice accretions in the two test methods focusing on full-scale aircraft conditions.

Neither Fast nor Slow: How to Fly Through Narrow Tunnels

Nowadays, multirotors are playing important roles in abundant types of missions. During these missions, entering confined and narrow tunnels that are barely accessible to humans is desirable yet extremely challenging for multirotors. The restricted space and significant ego airflow disturbances induce control issues at both fast and slow flight speeds, meanwhile bringing about problems in state estimation and perception. Thus, a smooth trajectory at the proper speed is necessary for safe tunnel flights. To address these challenges, in this letter, a complete autonomous aerial system that can achieve smooth flights through tunnels with dimensions as narrow as to 0.6 m is presented. The system contains a motion planner that generates smooth mini-jerk trajectories along the tunnel center lines, which are extracted according to the map and Euclidean distance field (EDF), and its practical speed range is obtained through computational fluid dynamics (CFD) and flight data analyses. Extensive flight experiments on the quadrotor are conducted inside multiple narrow tunnels to validate the planning framework as well as the robustness of the whole system.

Electrophysiological and behavioral responses of the moth, Trabala vishnou gigantina Yang, 1978 (Lepidoptera: Lasiocampidae) to volatiles produced by the plant, Hippophae rhamnoides L. (Elaeagnaceae)

Plant volatiles are important to herbivorous insects for foraging and determining host location. Considering the damage caused by the moth species, Trabala vishnou gigantina Yang, 1978 (Lepidoptera: Lasiocampidae), to sea buckthorn, Hippophae rhamnoides L. (Elaeagnaceae), plantations, this study examined the antennal and behavioral responses of T. vishnou gigantina to the volatiles produced by H. rhamnoides. Electroantennographs revealed large differences between males and females concerning active odor profiles. Subtractive bioassays conducted in a flight tunnel showed that the 14-component mixture (BLE) and a subtracted five-component mixture of 2-ethylhexyl acetate, longifolene, 3-heptanone, α-ocimene, and 6-methyl-5-hepten-2-one (treatment T-13) elicited equivalent responses in females. The BLE and a four-component mixture of 1-butanol, 3-methyl-1-butanol, 2-ethylhexyl acetate, and longifolene (treatment T-n) elicited equivalent responses in males. These findings indicate the potential for developing specific synthetic host plant lures and traps for T. vishnou gigantina. The attractive volatiles will also be helpful in future studies to gain further insights into the olfactory information processing in these insects.