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    <title>Transport Research International Documentation (TRID)</title>
    <link>https://trid.trb.org/</link>
    <atom:link href="https://trid.trb.org/Record/RSS?s=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" rel="self" type="application/rss+xml" />
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    <language>en-us</language>
    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
    <docs>http://blogs.law.harvard.edu/tech/rss</docs>
    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
    <image>
      <title>Transport Research International Documentation (TRID)</title>
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      <link>https://trid.trb.org/</link>
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    <item>
      <title>An Adaptive ADRC Strategy With Weight Function for Propeller Speed Control and Experimental Verification in Wind Tunnel</title>
      <link>https://trid.trb.org/View/2364807</link>
      <description><![CDATA[Electric propulsion system based on a propeller, driven by surface-mounted permanent magnet synchronous motor (SPMSM) directly, has been widely used in the aviation field. Due to the complexity of the wind field in the actual operating environment, the propeller speed controller needs adaptive abilities to meet the system’s performance requirements. Aiming at the problems of traditional active disturbance rejection controller (ADRC) control strategy such as a lack of flexibility and dynamic response in the electric propulsion system, an adaptive ADRC strategy with weight function is proposed in this article. First, the mathematical model of the electric propulsion system is developed, and then, the speed controller with linear and nonlinear characteristics is designed based on an adaptive weight function. Subsequently, the descriptive function method is used to deal with the nonlinear processing in the system, and the stability and disturbance estimation of the system are analyzed on this basis. Finally, the wind tunnel tests and disturbance simulations of the electric propulsion system are carried out, and the experimental results verify the feasibility and effectiveness of the proposed strategy.]]></description>
      <pubDate>Mon, 20 May 2024 09:17:59 GMT</pubDate>
      <guid>https://trid.trb.org/View/2364807</guid>
    </item>
    <item>
      <title>Development and flight test of a manned electric propulsion lightweight airplane</title>
      <link>https://trid.trb.org/View/2361901</link>
      <description><![CDATA[Electrically powered airplanes can cope with global warming by reducing the use of fossil fuels and reduce airplane costs in the long run through the efficient use of energy. For this reason, advanced aviation countries such as the United States and several countries in the European Union are leading the development of innovative technologies to realize a fully electric airplane in the future. Currently, research and development efforts are underway domestically to convert existing two-seater airplanes into electric-powered airplanes. In this study, the KLA-100X, which was developed by converting the existing two-seat lightweight sport airplane KLA-100 into an electric propulsion airplane, was introduced. In this text, the main specifications, design characteristics, and performance of KLA-100X are examined. In addition, the performance of the major components of the propulsion system, in this case the propulsion motor, inverter, and battery developed for application to KLA-100X are assessed, and the control system, additionally altered according to electric propulsion modification, is explained. Finally, the applicability of the developed major components to an electric propulsion airplane is confirmed by conducting ground and flight tests on the KLA-100X and presenting the results. In the future, the expansion of research aimed at improving the performance of current electric propulsion airplanes can be reviewed through the development of a dedicated platform for an electric propulsion airplane.]]></description>
      <pubDate>Tue, 30 Apr 2024 13:19:39 GMT</pubDate>
      <guid>https://trid.trb.org/View/2361901</guid>
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    <item>
      <title>Vertical tail sizing of propeller-driven aircraft considering the asymmetric blade effect</title>
      <link>https://trid.trb.org/View/1949026</link>
      <description><![CDATA[An engineering approach is presented to analyse the asymmetric blade thrust effect with the help of analytical and semi-empirical methods. It is shown that the contribution of the asymmetric blade thrust effect in the lateral-directional stability of multi-engine propeller-driven aircraft is significant particularly in critical flight conditions with one engine out of service. Also, in some cases where the engines are rotating in one direction, the asymmetric blade effect has substantial effects on the handling qualities of the aircraft even in normal flight conditions. Overall, due to the significant contribution of this phenomenon in the lateral-directional stability of propeller-driven airplanes, it is important to consider it in the design of the vertical stabilizer and rudder. The resulting analytical method has been used to determine the vertical tail incident angle and desired rudder deflection in accordance with the most critical flight condition for two different cases and validated to ensure the accuracy of the result. In this work, the aerodynamic coefficients as well as the stability and control derivatives have been predicted using analytical and semi-empirical methods validated for light aircraft.]]></description>
      <pubDate>Mon, 27 Jun 2022 17:19:56 GMT</pubDate>
      <guid>https://trid.trb.org/View/1949026</guid>
    </item>
    <item>
      <title>Numerical Study on the Effect of Vortex Generators on S-Shaped Intake in Propeller Slipstream</title>
      <link>https://trid.trb.org/View/1927347</link>
      <description><![CDATA[In turboprop engines, the lip of the S-shaped intake is behind the propeller rotation plane, so the complex slipstream flowfield has a strong impact on the flowfield in the S-shaped intake and affects engine performance. The present work attempts to improve the flowfield in the S-shaped intake in turboprop engines by using vortex generators. The research was carried out by solving Reynolds-averaged Navier–Stokes equations employed SST k-ω turbulence model. An attempt was made to explore the vortex generators’ effect on S-shaped intake performance in the propeller slipstream. The results show that the total pressure recovery coefficient and distortion coefficient change periodically with time for the S-shaped intake in the propeller slipstream. For S-shaped intake with vortex generators (s/sm=0.3, 12-mm height, 18° with the incoming flow) in the propeller slipstream, the vortices induced by the vortex generators are coupled with the propeller slipstream, which effectively inhibits flow separation in the S-shaped intake for turboprop engine and improves air quality on the aerodynamic interface plane (AIP) section of the S-shaped intake.]]></description>
      <pubDate>Wed, 25 May 2022 09:40:07 GMT</pubDate>
      <guid>https://trid.trb.org/View/1927347</guid>
    </item>
    <item>
      <title>Conceptual Design and Control of Twin-propeller Tail-sitter Mini-UAV : Conceptual Study of V-TS Mini-UAV</title>
      <link>https://trid.trb.org/View/1642104</link>
      <description><![CDATA[This paper describes progress made on the design and analysis of a twin-propeller tail-sitter mini-UAV (named V-TS). Since the V-TS mini-UAV is a combination of airplanes and copters, high energy efficiency during the forward flight and VTOL capability in the hover flight are achieved. However, this configuration also brings new challenges and difficulties, especially in the case of control. Free software which was used in the design process is presented and described. AVIGLE Demonstrator is analyzed in SU2 to verify correct settings of the aerodynamic analysis. Furthermore, 3D model of the V-TS mini-UAV with the Y-tail configuration and its basic geometrical parameters are shown. The results prove that it is aerodynamically efficient for our purpose. In addition, probably all control modes, transitional flight phases, and difficulties which appear in the control of the twin-propeller tail-sitter mini-UAV are defined and solutions are proposed. The transitional flight phases are determined as a combination of the control modes and sub-modes.]]></description>
      <pubDate>Wed, 18 Sep 2019 09:15:19 GMT</pubDate>
      <guid>https://trid.trb.org/View/1642104</guid>
    </item>
    <item>
      <title>Investigation and Improvement of Directional Stability and Control of a Propeller-driven STOL Aircraft</title>
      <link>https://trid.trb.org/View/1642102</link>
      <description><![CDATA[The scope of this paper is to investigate and improve the aerodynamic properties of a propeller driven state-of-the-art active high-lift configuration in lateral motion. 3D RANS simulations of the landing configuration with circulation control and slipstream deflection under crosswind, and one engine inoperative (OEI) conditions were performed. The configuration shows directionally unstable behavior at small sideslip angles and high yawing moment production under OEI conditions. Flowfield analyses indicate that both can be attributed to wake-tail interference effects caused by slipstream–vortex interaction. The integration of tail fences at the rear of the fuselage leads to considerable improvements for both conditions.]]></description>
      <pubDate>Wed, 18 Sep 2019 09:15:19 GMT</pubDate>
      <guid>https://trid.trb.org/View/1642102</guid>
    </item>
    <item>
      <title>Development and validation of an enhanced semi-empirical method for estimation of aerodynamic characteristics of light, propeller-driven airplanes</title>
      <link>https://trid.trb.org/View/1503842</link>
      <description><![CDATA[This study is intended to introduce an enhanced semi-empirical method for estimation of longitudinal and lateral-directional stability and control derivatives in the preliminary design phase of light airplanes. Specialised for light, single or twin propeller-driven airplanes, available state-of-the-art analytical procedures and design data compendia are combined and modified in a unique compatible method, and automated in NAMAYEH software. In the present study, modified procedures and the software structure are presented. Afterwards, the proposed method is applied to a four-place, low wing, single-engine, propeller-driven general aviation airplane. In order to validate the proposed method, the estimated aerodynamic characteristics are compared with the wind tunnel test data as well as DATCOM and VLM-based method estimations. The results indicate that the proposed method is able to predict the aerodynamic characteristics in an acceptable range of accuracy from zero-lift to stall conditions in all configurations.]]></description>
      <pubDate>Fri, 30 Mar 2018 09:51:21 GMT</pubDate>
      <guid>https://trid.trb.org/View/1503842</guid>
    </item>
    <item>
      <title>Wind tunnel and computational stability derivatives for a propeller-driven airplane</title>
      <link>https://trid.trb.org/View/1484930</link>
      <description><![CDATA[A comparison of wind tunnel test data with those obtained from vortex lattice-based AVL program was made for a power-off and stick-fixed model of a propeller-driven cargo airplane. For the airplane model, longitudinal and lateral-directional aerodynamics were investigated in stability-axis system. Also, experimental and computational static stability derivatives were compared. Their results agree reasonably well within the linear portion of force and moment characteristics. The comparative study should provide a benchmark for using the fast turn out computations to further improve the design of airplane.]]></description>
      <pubDate>Thu, 26 Oct 2017 12:31:45 GMT</pubDate>
      <guid>https://trid.trb.org/View/1484930</guid>
    </item>
    <item>
      <title>Conceptual Design Studies of Vertical Takeoff and Landing Remotely Piloted Aircraft Systems for Hybrid Missions</title>
      <link>https://trid.trb.org/View/1398260</link>
      <description><![CDATA[Spurred by the rapid progress in sensor performance increase associated with contemporary miniaturization, many companies, organizations, and governments are interested in using new opportunities in civil remotely piloted aircraft system applications. Coupled with an enhancement in propulsion system performance as well as an optimized and well-matched aerodynamic design, flight envelope limits can be enlarged and new mission profiles arise. Due to these ambitions, resulting hybrid missions become more complex and individual with partially contradicting demands, such as vertical takeoff and landing capabilities, fast climb and cruise combined with a long-endurance loiter capability, and a hover capability up to altitudes of 5000 m. In order to fulfill the diverse mission requirements, several configuration concepts are investigated. The focus is laid on different propulsion system concepts where various technologies and energy storage types are considered, as well as their effects on the aerodynamic shape and the controllability of the configuration. The investigated concepts comprise tilt propeller, tilt ducted propeller, and tilt wing configurations with fixed and variable pitch propeller. Based on these studies, a feasible concept in the weight category of MTOW ≤150 kg was identified which accomplishes both the aerodynamic and performance demands and the controllability in all flight segments.]]></description>
      <pubDate>Tue, 01 Mar 2016 09:19:45 GMT</pubDate>
      <guid>https://trid.trb.org/View/1398260</guid>
    </item>
    <item>
      <title>Design and Fabrication of a Scaled-Down Unmanned Quad-Tilt-Prop Personal Air Vehicle</title>
      <link>https://trid.trb.org/View/1326786</link>
      <description><![CDATA[This paper describes the design, fabrication, and test of a scaled-down unmanned personal air vehicle (PAV) with dual mode drive and flight capabilities. Considerations of the operational requirements of such a vehicle led to the concept of a quad-tilt-prop platform that has nacelle tilt capability with a multiple rotor configuration. Motors for both propeller propulsion and the driving mechanism were integrated into a single nacelle, and they were then implemented with a nacelle tilt mechanism for conversion between the drive and flight modes. The primary design parameters were examined through the conceptual design process, as follows: (1) overall dimensions, (2) empty weight, (3) propeller diameter, and (4) propulsion motor were determined based on design requirements. Functional tests were then performed, with test platforms designated for each development step. Comprehensive drive and flight tests demonstrated the operational capabilities of the finalized prototype. The fabricated vehicle has a takeoff weight of about 17 kg, including a 2-kg payload, an overall length of 1,000 mm, an overall width of 750 mm, and 12 min of flight endurance.]]></description>
      <pubDate>Wed, 29 Oct 2014 11:38:22 GMT</pubDate>
      <guid>https://trid.trb.org/View/1326786</guid>
    </item>
    <item>
      <title>Acoustical Flight Test of the Piper Lance</title>
      <link>https://trid.trb.org/View/1264124</link>
      <description><![CDATA[Research is being conducted by the Federal Aviation Administration (FAA) and other members of the International Civil Aviation Organization (ICAO) toward refinement of current noise regulation of propeller-driven small airplanes. These studies are examining the prospect of substituting a takeoff procedure of equal stringency for the level flyover certification test presently required. It was initially assumed that equivalency could be established between the takeoff and level flyover procedures via adjustment equations involving propeller helical-tip Mach number and noise propagation distance to account for differences in airspeed and altitude respectively. However, as test results became available, it was found that the propeller helical-tip Mach number adjustment equation did not adequately account for the measured noise level differences between the takeoff and level flyover procedure. After applying the adjustment equations, the takeoff noise levels were 3 to 4 decibels higher than the level flyover noise levels. This effect is believed to result from unsteady propeller blade loading when the aircraft is in a pitch-up position during a takeoff/climbout as opposed to level flight. The test aircraft was a Piper Cherokee Lance (PA-32R-300) equipped with a two-blade speed propeller. The objective required a series of flights ranging from level flyover to a takeoff/climbout performed at Vx (speed for best angle climb). Noise level versus propeller inflow angle was addressed by a series-to-series variation of aircraft speed at constant power and revolutions per minute (RPM). Since airspeed is a component of the helical-tip Mach number (MH) and given the generally strong influence of MH on noise levels, additional series of overflights were necessary to empirically relate MH to the noise levels actually produced by the Lance. The MH issue was addressed through a series-to-series variation of propeller RPM at constant power and airspeed.]]></description>
      <pubDate>Mon, 28 Oct 2013 09:47:10 GMT</pubDate>
      <guid>https://trid.trb.org/View/1264124</guid>
    </item>
    <item>
      <title>Enhanced Modeling of Aircraft Taxiway Noise, Volume 2: Aircraft Taxi Noise Database and Development Process</title>
      <link>https://trid.trb.org/View/1248084</link>
      <description><![CDATA[This report documents the technical approach, development, and application of the Integrated Noise Model/Aviation Environmental Design Tool (INM/AEDT) taxi noise dataset. Chapter 1 provides an introduction. Chapter 2 describes the assumptions necessary for incorporation of taxi noise within the INM/AEDT modeling framework. Chapter 3 details the various empirical and analytical taxi data sources utilized in this project. Chapter 4 lays out the proposed methodology for a taxi noise Noice-Power-Distance (NPD) dataset and applies it to a limited subset of aircraft types. Chapter 5 explains how the taxi NPD development process was extended across the complete INM aircraft fleet. In order to understand the implications of the modeling assumptions, Chapter 6 describes the uncertainty associated with single spectral class modeling, the chosen process for thrust-noise sensitivity, and application of a hybrid model for those aircraft for which empirical taxi data do not exist. Chapter 7 documents the NPD process for propeller aircraft NPDs. Chapter 8 contains the composite directivity pattern development procedures and resultant directivity patterns for both Turbofan (Jet) aircraft and Turboprop aircraft.]]></description>
      <pubDate>Mon, 22 Apr 2013 13:49:30 GMT</pubDate>
      <guid>https://trid.trb.org/View/1248084</guid>
    </item>
    <item>
      <title>Analysis of Aerobatic Aircraft Noise Using the FAA’s Integrated Noise Model</title>
      <link>https://trid.trb.org/View/1216158</link>
      <description><![CDATA[This project has three main objectives. The first objective is to model noise from complete aerobatic routines for a range of aircraft. The second is to compare modeled and previously measured aircraft noise from complete aerobatic routines for a range of aircraft. The third is to model the noise from up to 50 daily aerobatic routines for a range of aircraft. The end result of this analysis is a matrix of modeled noise results for a range of aircraft performing a variety of aerobatic routines. The Federal Aviation Administration (FAA) can now utilize these results to help set the technical threshold for approving National Environmental Policy Act analyses for aircraft performing aerobatic routine represented within the matrix.]]></description>
      <pubDate>Fri, 19 Oct 2012 15:52:40 GMT</pubDate>
      <guid>https://trid.trb.org/View/1216158</guid>
    </item>
    <item>
      <title>Operational Usage Information for a Commuter Propeller</title>
      <link>https://trid.trb.org/View/912781</link>
      <description><![CDATA[Wichita State University (WSU) supports the Federal Aviation Administration (FAA) research in the area of Operational Loads Measurement of commuter and general aviation aircraft. This research is aimed primarily at acquiring and reducing typical in-service usage data for the purpose of better understanding the flight loads experienced by the airframe. The program includes developing improved methods and criteria for processing and presenting large amounts of data. These activities result in information that can (1) lead to the understanding of the service-related factors affecting the operational life of the aircraft and (2) allow the FAA to reassess continued suitability of existing certification criteria. The University of Dayton Research Institute (UDRI) published the results from the processing and analysis of digital flight recorder data obtained from 910 flights of 30 BE-1900D aircraft during typical operational usage by a single commuter airline. These aircraft employ propellers with composite structures. The data used by UDRI also contained some information on engine and propeller usage, such as engine revolutions per minute (rpm) and torque and time at propeller reversal. This report documents the efforts of WSU to derive statistical summaries of aircraft usage data, ground operations data, and flight operations data pertaining to the propellers from this database. Statistical data are presented for parameters such as torque correlated with rpm, time in propeller reversal, alpha, and unsteadiness in alpha due to gust velocities. The scope of activities performed encompasses the service-related factors that affect the operational life of the propeller, as defined by the propeller manufacturer. WSU has generated the processed data in statistical formats that can enable the FAA, the propeller manufacturer, and the airline to better understand and control those factors that influence the structural integrity of these components.]]></description>
      <pubDate>Fri, 19 Feb 2010 10:58:04 GMT</pubDate>
      <guid>https://trid.trb.org/View/912781</guid>
    </item>
    <item>
      <title>Beech Super King Air 350</title>
      <link>https://trid.trb.org/View/887048</link>
      <description><![CDATA[Subtitle: Fill the tanks, fill the seats and make no excuses.]]></description>
      <pubDate>Mon, 06 Apr 2009 12:26:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/887048</guid>
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