Browse Topic: Flight tests

Items (1,195)
As global air traffic is expected to increase significantly in the coming decades, reducing the associated climate impact requires scalable solutions. While alternative propulsion technologies such as electric and hybrid-electric systems might offer long-term potential, their current applicability remains limited due to low energy density, limited range and scalability, and system complexity. Consequently, thermodynamic propulsion systems – such as gas turbines and piston engines – are expected to remain dominant in the medium term. In this context, sustainable hydrocarbon-based aviation fuels represent a practical and necessary solution. Certified sustainable aviation fuel (SAF) pathways are currently approved exclusively for use in gas turbines, with certification standards tailored to turbine-specific requirements. Consequently, fuel properties such as cetane number and evaporation behavior are not included in existing specifications. However, when SAF-kerosene blends are used in
Kleissner, FlorianHofmann, PeterVogd, PhilippVauhkonen, VilleKäkölä, JaanaGreve, Alina
The German Aerospace Center's (DLR) solar-powered high altitude platform (HAP) has completed ground vibration testing, in preparation for low altitude flight testing planned for 2026. German Aerospace Center (DLR), Cologne, Germany High-altitude uncrewed aircraft can remain in the lower stratosphere for extended periods, performing a wide range of Earth observation and communications tasks - from monitoring shipping lanes and supporting disaster response to providing internet access. The German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR) has now taken an important step in the development of its own high-flying solar aircraft by successfully completing a Ground Vibration Test (GVT) on its innovative HAP-alpha high-altitude platform. Extensive ground trials took place at DLR's National Experimental Test Center for Unmanned Aircraft Systems in Cochstedt, Germany. Further tests will follow and the first low-altitude flight trial is planned for 2026, subject to ideal
The return to Earth is a rough ride for astronauts, from the violent turbulence of atmospheric entry to a jarring landing. Hitting the ground in a Soyuz capsule is the equivalent of driving a car backward into a brick wall at 20 mph, and it’s resulting in more head and neck injuries than NASA computer models predicted. To collect more data, NASA’s Johnson Space Center in Houston commissioned a Small Business Innovation Research (SBIR) project to develop a wearable data recorder for astronaut spacesuits. One result, created by Diversified Technical Systems Inc. (DTS), is a miniature commercial device that now collects and transmits data for any application from airplane test flights to tracking high-value shipments.
Advancements in embedded processing, software, new product introductions, partnerships and recent demonstration flights reflect the growth in development of artificial intelligence (AI) and machine learning (ML) for military aircraft avionics systems occurring in the aerospace industry. This article highlights trends across several industry partnerships, demonstration flights and the enabling elements that are providing opportunities to integrate AI and ML into military avionics systems. In a June press release, Helsing, the Munich, Germany-based native software company and Saab, the Swedish defense manufacturer, announced their completion of a series of test flights where Helsing's “Centaur” AI agent controlled the aerial movements of a Gripen E fighter jet. AI agents are growing in popularity across many different industries for a variety of use cases. In a November 2024 blog about the topic, Microsoft described them as taking “the power of generative AI a step further, because
Launching atop NASA’s Space Launch System (SLS) rocket, Orion will carry four astronauts to lunar orbit and safely return them to Earth on Artemis missions. The Artemis II test flight will be NASA’s first mission with crew under Artemis. Astronauts on their first flight aboard NASA’s Orion spacecraft will confirm all of the spacecraft’s systems operate as designed with crew aboard in the actual environment of deep space.
Dufour Aerospace designs and manufactures an automated tilt-wing aircraft for critical cargo delivery missions. Emphasizing operational efficiency, the platform integrates path generation and tracking techniques tailored for the unique dynamics of tilt-wing flight and builds upon the existing lower level control. While there exist a myriad of methods for high-level aircraft automation ranging from PID to MPC, they often require a trade-off between complexity and the capability to handle non-linear dynamics of the system they are controlling. Hence, a lightweight, deterministic geometric path generation approach using clothoid-based transitions between three waypoints and a robust SO(3)- based path tracking controller adapted for tilt-wing dynamics are presented. Additionally, a high-level automation framework is introduced that includes failure mode handling for GNSS loss and communication breakdowns. This system ensures mission continuity and operational safety while supporting
Cook, Jacob
Several efforts have been made to develop Flight Test Maneuvers for Handling Qualities evaluations, aimed at quantifying the effects of vehicle characteristics and assistance systems on a Helicopter Air-to-Air Refueling mission profile. However, these Flight Test Maneuvers have not achieved widespread adoption, likely due to the substantial logistical challenges associated with tanker deployment. Depending on a tanker aircraft not only incurs significant costs but also requires extensive organizational effort and prior testing, before Handling Qualities can be evaluated for the aerial refueling capabilities of a new rotorcraft design. Additionally, these available Flight Test Maneuver setups are not standardized or widely applied to the same degree as Mission Task Elements of the Aeronautical Design Standard, which limits repeatability and comparability. A new approach is proposed to address these limitations by introducing a repeatable, standardized method to reveal Handling Qualities
Schmidt, SvenJusko, Tim
By its seventh flight after the first take-off, the RACER (Rapid And Cost-Effective Rotorcraft) demonstrator smoothly reached the targeted 220kts speed in stabilized forward flight, validating the high-speed compound architecture developed by Airbus Helicopters in the frame of Clean Sky 2 programme. During the flight envelope exploration, the dynamic behavior of the main rotor was carefully assessed, by monitoring the vibratory loads and validating its aeroelastic stability. Particular care was taken to validate the predicted stability domain of the Dual Rotor phenomenon, a particular case of flap-lag coupling associated with high-speed flight conditions. This paper presents the most significant results shaping the success of RACER flight test campaign. After having introduced the theoretical background and the associated analytical equations, the simulation framework based on the comprehensive analysis tool STORM is presented to discuss the numerical resolution of the stability
Skladanek, YanCoisnon, RemiFerullo, David
Low-level flight, defined by high-speed operations near terrain, represents a significant challenge in military rotorcraft missions while providing strategic advantages, such as radar evasion and heightened surprise. Recent conflicts highlight the urgent need for advanced low-level flight capabilities in the design of new rotorcraft. The close proximity to ground obstacles, combined with the complexities of piloting, necessitates precise control and robust handling qualities to prevent accidents. However, existing handling quality standards, such as MIL-DTL-32742, reveal limitations in assessing low-level maneuvers. Given the diverse array of new rotorcraft designs, driven by initiatives like the U.S. Army's Future Vertical Lift and NATO's Next Generation Rotorcraft Capabilities, a customized handling qualities evaluation for each design is impractical. In response, a performance-driven strategy has been implemented, scaling Mission Task Elements to align with aircraft performance
Jusko, TimBerger, TomWalko, Christian
A cooperative flight test campaign between the US Army and NASA was performed. This test sought to characterize the acoustic emissions of a fully instrumented MD530F helicopter using a snapshot array and a phased array of microphones. The snapshot array of microphones aimed to provide even coverage across the surface of a hemisphere, providing an acoustic emission hemisphere in a single 'snapshot' of time. The phased array of microphones was designed to provide enough resolution to determine noise sources from each individual blade as well as perform source separation from main rotor and tail rotor emissions. Test conditions for the characterization effort were chosen using a traditional one-factor-at-a-time approach as well as three design of experiment approaches. Characterization conditions included constant speed level flight, descent, and ascent conditions. Transient maneuver conditions were also captured over the snapshot array. The vehicle instrumentation included measurements
Stephenson, JamesPascioni, KyleHouston, MaryStutz, ColinPreston, Martin
A cooperative acoustics flight test campaign between the US Army and NASA was performed in which design of experiments (DOE) approaches were used to plan the flight test conditions. Three DOE designs were used, a face centered central composite design, circumscribed central composite design, and a hexagonal design. A traditional one-factor-at-a-time approach was also used, and interpolation points were planned to test for the strength of the DOE approaches. This paper documents the design methodology, discusses how response surface models were fit to the data, evaluates the overall response of the models, and evaluates the individual DOE designs. The response surface models were also used to design new test conditions of interest during the experiment, and that process is also documented. For the first time, DOE was shown to be an exceptionally useful tool for rotorcraft acoustics flight test planning, while the full power of the approach has yet to be reached.
Stephenson, JamesPascioni, Kyle
This paper discusses the development of a quantitatively-accurate non-linear hybrid flight dynamics model of a hover-capable Air-Launched Tailsitter Unmanned Aerial System (ALUAS) in order to 1) understand its dynamics during complicated maneuvers, and 2) provide a high-fidelity framework to develop novel control laws. Wind tunnel tests were conducted on a 1:1 scale model of the full aircraft to measure the airloads, which were used in the simulation as a lookup table. Flight tests of the ALUAS were performed in hover, transition, and cruise to collect a large amount of unique state measurements by providing large excitations to induce highly transient motion. The flight dynamics predictions using Rotorcraft Comprehensive Analysis System (RCAS) software were then compared with experimental flight test data. To correct any discrepancies in the RCAS physics-based predictions, a correction was learned from the experimental measurements, making use of the large amount of collected flight
Stewart, Reuben-WayneDooher, JackBenedict, Moble
In April of 2024, Sikorsky flight tested an open loop Higher Harmonic Control system on an S-97® helicopter. The S-97® helicopter is a prototype aircraft, based on Sikorsky's X2 Technology™, that first flew in May 2015. It has contra-rotating, stiff in-plane main rotors with fly-by-wire controls, and a pusher propeller. This paper describes the HHC design, how it was implemented on the aircraft, how it was tested, and what the test results were.
Monico, Michael R.Millott, Thomas A.Brigley, Mikel J.Renzulli, Eric J.Ryan, David M.
Aeroelastic stability prediction is critical to the successful design, development and flight testing of rotorcraft. As configurations reach higher speeds, new challenges in high Mach number unsteady aerodynamic modeling need to be addressed, especially for higher frequency aeroelastic modes with significant coupling. In this paper, Linear Unsteady aerodynamics and Leishman-Beddoes attached flow models are applied and compared to 2D CFD (airfoil) and 3D CFD/CSD (rotor) analysis for operating conditions of interest. The Leishman-Beddoes model demonstrates improved agreement with CFD data. In the 2D assessment, RCAS is used to model a representative airfoil undergoing prescribed pitch and heave oscillations. CFD results are presented to compare each model (Linear Unsteady and Leishman-Beddoes). In the 3D assessment, a full rotor CFD/CSD test case is evaluated for aeroelastic stability and compared to RCAS standalone analysis. The RCAS rotor structural model is coupled with the HELIOS CFD
Buccio, AngelaSchmaus, JosephAhaus, LorenHill, MatthewXin, Hong
A robust velocity stability augmentation system was developed for the CoAX 600/2D coaxial-rotor helicopter to enable safe testing of a fly-by-wire system on an optionally piloted variant of the aircraft, developed by Piasecki Aircraft Corporation. The control law design and subsequent stability analysis were based on a validated nonlinear model of the CoAX 600 rotorcraft. A subset of helicopter handling qualities were evaluated through both analytical methods and piloted simulations, conducted with and without the stability augmentation system. Additionally, flight test data contributed to the analysis, albeit to a limited extent.
Hosseini, BarzinBridges, DerekHagwood, GreyRauleder, JuergenMiller, DougBachfischer, MichaelHolzapfel, Florian
The transition phase of eVTOL aircraft poses a challenge in balancing energy efficiency and stability. This study presents the development and evaluation of an automatic flight control system for eVTOL transition phases, focusing on minimizing energy consumption while ensuring robust performance. The control architecture implements a hybrid response type combining Translational Rate Command below 5 knots and Acceleration Command Speed Hold above 5 knots, with control allocation dynamically adjusted based on airspeed and rotor shaft angle. Stability analysis reveals surge mode instability at high shaft angles due to negative speed stability derivatives, stabilized through carefully tuned feedback control. The system demonstrates Level 1 handling qualities against bandwidth, quickness, and disturbance rejection criteria when evaluated against MIL-DTL-32742 and MIL-STD-1797B standards. Simulation results verify the control system's ability to maintain precise acceleration/deceleration
Kang, NamukLu, LinghaiWhidborne, James
In this paper, we develop a new feature-based algorithm using stereo cameras to estimate stochastic ship-deck motion at high sea states. Unlike our previous algorithms, this algorithm is able to estimate the motion of arbitrary ship structures without prior information on the ship's visual appearance or geometry. The algorithm requires an initial pose and suffers from drift over time, which was resolved by fusing it with our previous 2D feature-based vision algorithm. The combined vision algorithm is validated using a simulated ship featuring 3D ship structures and 2D flight deck markings representative of a DDG-51 ship. The results indicate that the algorithm can accurately estimate the pose of a simulated ship undergoing Sea-State 6 motion. The vision algorithm was further validated in a simple free-flight test.
Chopra, Inderjit
Developed in the frame of the European Clean Sky 2 program, the RACER High Speed Helicopter Demonstrator of Airbus performed its maiden flight on April 25th, 2024. In the continuity of the previous high-speed demonstrator X3 (1st flight in 2010) the RACER is a 7/8t (15000 / 18000 lb) class compound helicopter powered by two SHE Aneto-1X engines, including a wing and two propellers. The tail rotor is removed as the two propellers control the yaw axis by differential thrust. At flight 07, with its initial default settings, it reached a true airspeed of 227 kts in level flight, exceeding its objective of 220 kts.
Eglin, PaulEmbacher, MartinDesvigne, DamienRoca-Leon, Enric
This paper presents handling qualities (HQs) research findings for electrical Vertical Take-off and Landing vehicles. Testing in the Vertical Motion Simulator (VMS) investigated handling qualities of vehicle configurations having a degraded powertrain. Powertrain components, including batteries and electric motors, can degrade as the vehicle is flown. This paper investigates the impact of low battery charge and high motor temperature degradations on the pilot's ability to execute precise maneuvers. Pilot comments and ratings that were collected from four rotorcraft test pilots in VMS testing are used to quantify the effects that powertrain degradations had on the HQs of the vehicle.
Barnes, KyleSuh, PeterHanson, Curt
Urban Air Mobility (UAM) aircraft are highly susceptible to turbulent wind disturbances when operating near buildings in complex urban environments. Microscale wind phenomena, combined with the unconventional designs of UAM aircraft, increase the risk of performance deviation, the overall duration, and the cost of flight tests for certification. A way to overcome this would be through simulation-based flight tests. Therefore, this study simulates a UAM aircraft landing vertically behind an isolated tall building, considering four different wind scenarios: no wind, uniform wind fields at low and high spatial resolutions (assumed constant across the airframe), and non-uniform fields with spatially varying velocity profiles at individual rotor hubs. The resultant flight test data are then used to quantify the impact of microscale wind characteristics on landing performance by systematically analyzing the rotor performance, aerodynamics, control response, and trajectory deviation.
D S, NithyaQuaranta, GiuseppeMuscarello, VincenzoLiang, Man
Flight test students must explore a wide range of helicopter dynamic responses to learn how to assess conditions ranging from good conditions operation to those approaching, or even experiencing, loss of control. To introduce this evaluation process, the Flight Test and Research Institute (IPEV) implemented a helicopter flight dynamics model. This model is stitched in the x-body velocity (u) and y-body velocity (v) to achieve more accurate simulation, combined with a Variable Stability Augmentation System to assess different conditions prior to experiencing them in real flight. The use of robust control, where a fixed controller is applied to flight control systems under various operating conditions, presents an alternative to the traditional gain scheduling technique commonly used in aeronautical systems. This paper explores the potential to reduce controller design complexity while evaluating the impact on the helicopter’s full flight envelope through quantitative analysis and
Moro, Luis G.Ribeiro, Flávio C. L.Cruz, Ronaldo V.
The influence of ground, wall, and corner boundaries on multirotor vehicle performance was investigated through a series of controlled flight tests. Changes in rotor inflow profiles were represented by near-field rotor pressure measurements captured by a custom Kiel probe wake rake. Ground effect was characterized by reduced thrust and power requirements, primarily driven by the vehicle fuselage, which induced regions of reduced pressure and increased flow unsteadiness around the airframe. Operating near a wall boundary was found to restrict airflow into the portion of the rotor disk closest to the wall, leading to increased power requirements to maintain hover and a consequent reduction in performance. While vehicle orientation had minimal impact on overall rotor performance, it did influence local rotor inflow behavior near the wall, depending on the relative position of the interaction region formed with adjacent rotors. As the vehicle descends from the isolated wall effect into
Herz, SageMcCrink, Matthew
This paper presents a robust and adaptable control system for tilt-wing aircraft, developed by Dufour Aerospace. The transitional tilt-wing aircraft, Aero2, combines the vertical takeoff/landing capabilities of helicopters with the high-speed range of fixed-wing aircraft. Addressing the inherent control complexities required to maintain control and stability, the developed system employs established control techniques, utilizing linearization at trim points and gain scheduling based on wing tilt. The architecture comprises a Control Allocation module for optimal actuator management, a Control Augmentation System utilizing an LQRI controller enhanced with a feedforward component for precise attitude tracking, and a Unified Velocity Controller for seamless transitions between ground speed tracking in hover and airspeed tracking in cruise. Special challenges unique to transitioning aircraft to ensure control in all axes, including in windy conditions are addressed with operational
Studiger, MatthiasCook, Jacob
Pilot workload assessment has been a keen area of research for many years and has key applicability in flight testing. This paper outlines the development of a novel workload rating scale and index, the Comeau-Duggan Pilot Workload Index, which bridges gaps, such as causal factor identification, between some of the most widely used rating scales in flight test. The conceptualization and evolution of this index has been a multi-year and multi-nation research effort that has built upon the foundation and fundamental principles that underpin current widely accepted workload rating scales used in Human Factors and Handling Qualities engineering. The pilot workload index facilitates a rigorous and robust methodology for identifying the factors contributing to a given flying task, quantifying their impact through a structured suffix flowchart approach. It can provide, for example, a quantifiable link between pilot workload and the operational use of the aircraft, and therefore could inform
Duggan, LaurenComeau, PerryWhite, MarkDadswell, Christopher
Big Data technologies have become quite ubiquitous in the last years, allowing for the storage of substantial amounts of data, typically flight test data as recorded by the flight test installation. On recent helicopter prototypes, we generate in excess of 50 GB of raw data per flight hour, usually in a format not adequate for efficient large-scale processing. With some specific optimizations and the setup of a specialized infrastructure, there are now practicable means to store timeseries in ways that allow for requests spanning hundreds or thousands of flights to complete within minutes, opening the way to some substantial savings and new insights. However, to make the most of these data and make informed decisions it is often quite important to store contextual data that go beyond the pure timeseries data, typically on helicopters where optional installations can have a significant impact on aircraft performance or behavior. This paper explores the various kinds of data and metadata
Brisset, Nicolas
This paper introduces a comprehensive model, specifically developed to inherently capture interactional effects. Due to the high computational cost associated with the large analysis matrix including variations in angle of attack, angle of sideslip, velocity, and weight, a surrogate model is used in creating aerodynamic databases. This database, which reflects interactional effects under a wide range of flight speed, angle of attack, angle of sideslip, and weight configuration, is integrated into a rotorcraft analysis tool. Simulations are performed, and results are compared against flight test data for the T625 Gökbey, covering low-speed, high-speed, rightward and climb conditions. The results highlight the impact of interactional aerodynamics on flight characteristics and load predictions. Overall, the study emphasizes the importance of including interactional effects to ensure accurate and reliable rotorcraft design in the early design stages without requiring flight test data.
Erkan, Mehmet AliMadenci, Mustafa AlperenGüngör, OsmanŞenipek, MuratEzertaş, Ahmet Alper
While known and largely studied, the Vortex-Ring-State (VRS) phenomenon remains the cause of numerous accidents every year and many questions are still open. In order to better understand the VRS phenomenon on different kinds of helicopters and to evaluate the effectiveness of recovery manoeuvres such as the one proposed by Capt. Vuichard, the European Union Aviation Safety Agency (EASA) launched the Helicopter Vortex-Ring-State Experimental Research project (EASA.2022.C11). Both objectives required to set-up flight test campaigns on two helicopter types, with a total of eight flights performed during the project. In addition to the description of the procedures that such flights required, the paper presents the Flight Test Instrumentation used and the analyses of the flight test data, including vibration measurements. Thus, flight conditions at which the VRS starts to develop, main parameters that influence and contribute to VRS symptoms and effects, or the effectiveness of the
Binet, LaurentGasquez, PhilippeDi Caprio, Raffaele
The Rotor Blown Wing (RBW) is a tailsitter Vertical Takeoff and Landing (VTOL) Unmanned Aerial System (UAS) configuration that leverages cutting-edge autonomous flight controls through Sikorsky's MATRIX™ technology to create a highly capable, efficient, and scalable technology platform. By combining the benefits of fixed- and rotary-wing aircraft, the RBW configuration eliminates the need for traditional UAS launch and recovery infrastructure. This paper describes the RBW-5 prototype, a 100-pound, dual 5-foot diameter proprotor demonstrator, and discusses the comprehensive evaluation of its design and operability through a combination of flight tests, wind tunnel experiments, and computational fluid dynamics (CFD) simulations. The results demonstrate the maturity of the UAS and highlights key accomplishments of the RBW-5 program, including successful autonomous takeoff and landing and transitions between hover and forward flight, the extraction of critical "blown-physics" underlying
Regan, MarcKlimchenko, VeraSargent, CalWallace, BrianRivera, AntonioKaye, JordanSatira, JasonBowles, PatrickColeman, Dustin
The Sikorsky BLACK HAWK® is the primary medium lift helicopter for the U.S. Army performing a wide range of missions that encompass Air Assault, MEDEVAC, CSAR, Command and Control, and VIP transport. The Multimission UH-60M is one of the latest in the BLACK HAWK helicopter product family, more capable, more survivable, more maintainable, more powerful, and more effective than its predecessors. In previous efforts, a high-fidelity CFDCSD based full-aircraft trim and maneuvering simulation methodology was developed and applied to model both coaxial aircraft and single main/tail rotor configurations (Refs. 1-4). The CFD solver is based on the CREATE™-AV HELIOS toolset (Ref. 5) and the CSD solver is based on Rotorcraft Comprehensive Analysis System (RCAS) (Ref. 6). The current paper further enhances the previously developed 6-DOF CFD-CSD full-aircraft trim methodology to robustly handle the trim solution for the single main/tail rotor configurations. The enhanced methodology was applied to
Zhao, Jinggen
Acoustic flight testing of rotorcraft often involves generating noise source hemispheres to gain an understanding about the aircraft's acoustic emissions. However, aerodynamically complex Urban Air Mobility and Future Vertical Lift vehicles may not maintain a steady aerodynamic state during flight, making source hemispheres measured using traditional linear arrays unreliable or difficult to interpret. To address this challenge, all emission angles need to be measured simultaneously. This has lead to the concept of the two dimensional 'snapshot' array layout. A mathematically defined microphone distribution was utilized to achieve uniform coverage on the source hemisphere. Within the chosen distribution, two lower microphone count distributions are embedded, allowing for a comparison of the effects of number of microphones. The array was deployed as part of a joint Army/NASA acoustic research flight test in July of 2024. Data were collected using an MD530F helicopter as the test vehicle
Houston, MaryStephenson, JamesPascioni, KyleStutz, Colin
This paper explores the effect of addition of a horizontal tail on the longitudinal stability and performance of a Biplane Tailsitter Unmanned Aerial Vehicle (UAV). Biplane tailsitters a type of hybrid UAVs, often exhibits poor longitudinal stability during forward flight, necessitating continuous active control through application of differential motor thrust to maintain attitude. To address this challenge, this work proposes the integration of a horizontal tail on a quadrotor biplane tailsitter UAV, aiming to improve pitch stability and control authority during critical flight phases. Experimental flight data was utilized to determine the appropriate sizing of the elevator. A detailed flight dynamics model validated the effectiveness of the elevator control. The design was validated through outdoor flight testing, comparing the performance of tail-less and tail-attached configurations. The results demonstrate that the modified design results in a reduction control power requirement
Murkute, NikhilGupta, ShubhanshuAbhishek, Abhishek
The Sikorsky Boeing SB>1 DEFIANT is a technology demonstrator aircraft that was built under the Joint Multi-Role Technology Demonstrator (JMR TD) program to address the next generation performance requirements of the US Army Future Vertical Lift (FVL) initiative. The Main Rotor Gearbox (MRGB) incorporated several low Technology Readiness Level (TRL) technologies to improve power density and meet challenging program requirements for gearbox empty weight fraction. After the conclusion of the flight test program the ground test Main Rotor Gearbox was disassembled and evaluated to raise the TRL level of these technologies. The technology insertions, teardown observations, and laboratory test results are discussed.
Bouwer, ScottIgnatuk, Kevin
The empennage of a helicopter is largely responsible for its stability in forward flight. Its performance is mainly determined by its aerodynamics. In this paper, the empennage of a CoAX 2D ultralight research helicopter is analyzed in detail. For this purpose, the helicopter was equipped with flow measurement devices and flight tests were performed, covering different flight conditions. Measurements from a nose boom as well as the pilot’s control inputs and helicopter's position are available for evaluation. For the empennage in particular, seven-hole flow probes were mounted on it and various cameras were used to record the movement of the surface tufts.
Rottmann, LukasPaintner, RafaelMüller, DanielHunold, Julian
This paper investigates the use of multi-modal cueing through full-body haptic feedback to enhance pilot-vehicle system (PVS) performance, reduce mental workload (MWL), and increase situational awareness (SA) in both good and degraded visual environments (GVE/DVE). Piloted simulations were conducted using an H-60-like flight dynamics model in a virtual reality (VR) motion-based simulator, evaluating two ADS-33-like mission task elements (MTEs) – precision hover and slalom – under visual-only and combined visual and haptic feedback conditions in both GVE and DVE. The H-60 flight dynamics were augmented with a dynamic inversion (DI)- based stability augmentation system (SAS), implementing rate-command/attitude hold (RCAH) response type on the roll, pitch, and yaw axes and altitude hold response type on the vertical axis. The SAS was designed to achieve Level 1 handling qualities per ADS-33 standards. The full-body haptic cueing strategy leveraged an outer-loop DI control law, which
Morcos, Michael T.Saetti, UmbertoGeiger, Derek H.Kubik, Stephen T.Breed, Adam R.Crane, Clifton J.Luzzani, GabrieleFischer, Madeline R.Jun, DogyuGary, Evan
IEEE-1394b, Interface Requirements for Military and Aerospace Vehicle Applications, establishes the requirements for the use of IEEE Std 1394™-2008 as a data bus network in military and aerospace vehicles. The portion of IEEE Std 1394™-2008 standard used by AS5643 is referred to as IEEE-1394 Beta (formerly referred to as IEEE-1394b.) It defines the concept of operations and information flow on the network. As discussed in 1.4, this specification contains extensions/restrictions to “off-the-shelf” IEEE-1394 standards and assumes the reader already has a working knowledge of IEEE-1394. This document is referred to as the “base” specification, containing the generic requirements that specify data bus characteristics, data formats, and node operation. It is important to note that this specification is not designed to be stand-alone; several requirements leave the details to the implementations and delegate the actual implementation to be specified by the network architect/integrator for a
AS-1A Avionic Networks Committee
Leonardo UK One Eagle Place London, SW1Y 6AF +44 (0)20 7340 6100
Hypersonic platforms provide a challenge for flight test campaigns due to the application's flight profiles and environments. The hypersonic environment is generally classified as any speed above Mach 5, although there are finer distinctions, such as “high hypersonic” (between Mach 10 to 25) and “reentry” (above Mach 25). Hypersonic speeds are accompanied, in general, by a small shock standoff distance. As the Mach number increases, the entropy layer of the air around the platform changes rapidly, and there are accompanying vortical flows. Also, a significant amount of aerodynamic heating causes the air around the platform to disassociate and ionize. From a flight test perspective, this matters because the plasma and the ionization interfere with the radio frequency (RF) channels. This interference reduces the telemetry links' reliability and backup techniques must be employed to guarantee the reception of acquired data. Additionally, the flight test instrumentation (FTI) package needs
Heather Cummings, a 27-year old senior flight controls and autonomy engineer at Sikorsky, is the winner of the Aerospace/Defense category for SAE Media Group's inaugural Women in Engineering: Rising Star Awards program. In addition to her role developing flight control software and improving Sikorsky's Innovations department's processes for software and model-based systems engineering, she is also a pilot. Among her career accomplishments at Sikorsky include leading the flight controls software development and flight testing program on a technology demonstrator aircraft for autonomy and reduced crew operations. The project involved Heather dividing up sub-tasks for the project and working with each individual on the team to mentor them on the engineering skills necessary for completion. She also served as the onboard flight test engineer for the project. One of her career goals is to serve as the lead engineer on new technologies that form the next generation of semi and fully
Air Force Test Pilot School Edwards Air Force Base, CA 661-277-1110
Innovators at NASA Johnson Space Center have developed and successfully flight tested a high-performance computing platform, known as the Descent and Landing Computer (DLC), to suit the demands of safe, autonomous, extraterrestrial spacecraft landings for robotic and human exploration missions.
Air Force Test Pilot School Edwards Air Force Base, CA 661-277-3510
Lockheed Martin Orlando, FL 407-284-9248
Data from a 3.43 kW piston engine-generator is integrated with rotorcraft sizing analysis to assess its impact. First, the measured SFC map of the powerplant is modeled. Second, the sizing is validated with XV-15 flight test aircraft and NASA conceptual reference quadrotor. The power and platform models are then integrated to size a hypothetical quadrotor bi-plane unmanned air vehicle of 5 lb payload. Several cases for how the engine can be operated to meet the vehicle torque and speed are detailed. The key conculsion is that a detailed SFC model is as important as the aircraft model. Without it, errors in tip speed reduction, gross weight, and range would be quite dramatic from 50-100%. A tip speed reduction to 65% hover in cruise was found to strike the best balance between rotor performance and engine performance of the hypothetical aircraft, resulting in a gross weight of 50 lb and range of 120 nm at 60 kts cruise speed.
Arace, MattDatta, Anubhav
The multi-role utility helicopter T625 GÖKBEY is designed by Turkish Aerospace and it is equipped with a pair of two-spool CTS800-4AT turboshaft engine developed by Light Helicopter Turbine Engine Company (LHTEC). Components of the cowlings, intakes and exhausts were designed with supplementing CFD analyses and performance of various alternatives were evaluated. Final designs were achieved based on the helicopter performance and engine limits. In order to verify the estimated engine installed performance in design phase, performance of the instrumented engine with its integrated equipment on the platform is examined using flight test data. This paper focuses on the CFD simulations based performance predictions of the air induction system, exhaust system, and IPS blower exhaust. A comprehensive study is assessed to create more realistic models by using flight test data.
Sancar, EmreEzertaş, Ahmet AlperBayat, AkayÇakıroğlu, TaylanDaldal, Abdurrahman Burak
Through the development and flight testing of the Canadian Vertical Lift Autonomy Demonstration (CVLAD) Autonomous Flight System (AFS), the NRC has developed technical and operational insight into many high-level concepts of a full-scale supervised-autonomous helicopter, which are thought to be applicable to a wide variety of implementations and approaches. This paper presents two important concepts: "The Contract" and "Levels of Aggression", for which it is expected some aspect of implementation would be required in any supervised autonomous platform and in particular for platforms where the pilot supervising the autonomy remains on-board the aircraft (and thus the AFS provides a 'competent co-pilot' type functionality).
Gowanlock, DerekComeau, PerryCarrothers, BryanGubbels, ArthurEllis, KrisJennings, Sion
Current Rotorcraft Developments like under the Future Vertical Lift Program in the USA (e.g. Bell V-280, see figure 1) respectively RACER (Airbus Helicopters, see figure 2) and NextGENCivil Tiltrotor (Leonardo, see figure 3) in Europe deal with High-Speed Rotorcraft or Tiltrotor-/Tiltwing Aircraft. They can expand and optimize their performance by using a variable rotor speed either to adopt the rotor speed to high forward speed or to meet the different requirements of a rotor in Hover and Aircraft Mode of a Tiltrotor-/Tiltwing Aircraft. As the required speed range can not be covered by the turbine, TU Munich (Germany), TU Wien (Vienna, Austria), ADT - Advanced Drivetrain Technologies (Austria) and Zoerkler Gears (Austria) work in the transnational project "VARI-SPEED II" on a rotor system that can change the rotor speed via change of the ratio of the transmission (variable rotor speed with constant turbine speed). The project is based on the results of "VARI-SPEED" and the direct
Scheu, ThomasKoch, JonasPoks, AgnesWeigand, Michael
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