In-Flight Wingtip Folding: Inspiration from the XB-70 Valkyrie
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Method to Assess Lateral Handling Qualities of Aircraft with Wingtip Morphing
Method to assess lateral handling qualities of aircraft with wingtip morphing Ga´etanDussart∗, Sezsy Yusufy, Vilius Portapas z, Guillermo Lopezxand Mudassir Lone{ Cranfield University, Dynamic Simulation and Control Group Cranfield, Bedfordshire, United Kingdom, MK43 0AL The impact of in-flight folding wingtip on roll characteristics of aircraft has been studied in the past. In this study, a handling qualities assessment carried out to de-risk further de- velopment of such a device. A specialised flight simulation campaign is prepared to evaluate the roll dynamics in different morphing configurations. Various manoeuvres, including the Offset Landing Manoeuvre and herein presented Slalom and Alignment Tracking task are used. Cooper Harper Rating scales and flight data analysis are used to collect pilot opinion and validate pilot-in-the-loop simulation results. This example is used to demonstrate the use of the slalom and Alignment Tracking manoeuvre for lateral dynamic assessment. I. Introduction A means to improve aircraft performance is to increase aircraft wingspan and raise aerodynamic effi- ciency.1,2 Then to comply with airport infrastructure limits, ground folding wingtips can be implemented as a solution, as seen on the NASA SUGAR concept (Fig.1a) or the Boeing 777X aircraft (Fig.1b). Moreover, in-flight folding can be considered to further justify the mechanism weight penalty and consolidate concept's viability. Two key applications were initially identified: gust loads alleviation capability demonstrated in past work,1 and flight dynamic and performance modifications, carried out through the preliminary identifi- cation of effect on key aerodynamic derivatives.3 This particular research demonstrated shifts of noticeable amplitude and trends in key lateral aerodynamic derivatives of a large generic aircraft. -
University of Oklahoma Graduate College Design and Performance Evaluation of a Retractable Wingtip Vortex Reduction Device a Th
UNIVERSITY OF OKLAHOMA GRADUATE COLLEGE DESIGN AND PERFORMANCE EVALUATION OF A RETRACTABLE WINGTIP VORTEX REDUCTION DEVICE A THESIS SUBMITTED TO THE GRADUATE FACULTY In partial fulfillment of the requirements for the Degree of Master of Science Mechanical Engineering By Tausif Jamal Norman, OK 2019 DESIGN AND PERFORMANCE EVALUATION OF A RETRACTABLE WINGTIP VORTEX REDUCTION DEVICE A THESIS APPROVED FOR THE SCHOOL OF AEROSPACE AND MECHANICAL ENGINEERING BY THE COMMITTEE CONSISTING OF Dr. D. Keith Walters, Chair Dr. Hamidreza Shabgard Dr. Prakash Vedula ©Copyright by Tausif Jamal 2019 All Rights Reserved. ABSTRACT As an airfoil achieves lift, the pressure differential at the wingtips trigger the roll up of fluid which results in swirling wakes. This wake is characterized by the presence of strong rotating cylindrical vortices that can persist for miles. Since large aircrafts can generate strong vortices, airports require a minimum separation between two aircrafts to ensure safe take-off and landing. Recently, there have been considerable efforts to address the effects of wingtip vortices such as the categorization of expected wake turbulence for commercial aircrafts to optimize the wait times during take-off and landing. However, apart from the implementation of winglets, there has been little effort to address the issue of wingtip vortices via minimal changes to airfoil design. The primary objective of this study is to evaluate the performance of a newly proposed retractable wingtip vortex reduction device for commercial aircrafts. The proposed design consists of longitudinal slits placed in the streamwise direction near the wingtip to reduce the pressure differential between the pressure and the suction sides. -
CANARD.WING LIFT INTERFERENCE RELATED to MANEUVERING AIRCRAFT at SUBSONIC SPEEDS by Blair B
https://ntrs.nasa.gov/search.jsp?R=19740003706 2020-03-23T12:22:11+00:00Z NASA TECHNICAL NASA TM X-2897 MEMORANDUM CO CN| I X CANARD.WING LIFT INTERFERENCE RELATED TO MANEUVERING AIRCRAFT AT SUBSONIC SPEEDS by Blair B. Gloss and Linwood W. McKmney Langley Research Center Hampton, Va. 23665 NATIONAL AERONAUTICS AND SPACE ADMINISTRATION • WASHINGTON, D. C. • DECEMBER 1973 1.. Report No. 2. Government Accession No. 3. Recipient's Catalog No. NASA TM X-2897 4. Title and Subtitle 5. Report Date CANARD-WING LIFT INTERFERENCE RELATED TO December 1973 MANEUVERING AIRCRAFT AT SUBSONIC SPEEDS 6. Performing Organization Code 7. Author(s) 8. Performing Organization Report No. L-9096 Blair B. Gloss and Linwood W. McKinney 10. Work Unit No. 9. Performing Organization Name and Address • 760-67-01-01 NASA Langley Research Center 11. Contract or Grant No. Hampton, Va. 23665 13. Type of Report and Period Covered 12. Sponsoring Agency Name and Address Technical Memorandum National Aeronautics and Space Administration 14. Sponsoring Agency Code Washington , D . C . 20546 15. Supplementary Notes 16. Abstract An investigation was conducted at Mach numbers of 0.7 and 0.9 to determine the lift interference effect of canard location on wing planforms typical of maneuvering fighter con- figurations. The canard had an exposed area of 16.0 percent of the wing reference area and was located in the plane of the wing or in a position 18.5 percent of the wing mean geometric chord above the wing plane. In addition, the canard could be located at two longitudinal stations. -
Aircraft Winglet Design
DEGREE PROJECT IN VEHICLE ENGINEERING, SECOND CYCLE, 15 CREDITS STOCKHOLM, SWEDEN 2020 Aircraft Winglet Design Increasing the aerodynamic efficiency of a wing HANLIN GONGZHANG ERIC AXTELIUS KTH ROYAL INSTITUTE OF TECHNOLOGY SCHOOL OF ENGINEERING SCIENCES 1 Abstract Aerodynamic drag can be decreased with respect to a wing’s geometry, and wingtip devices, so called winglets, play a vital role in wing design. The focus has been laid on studying the lift and drag forces generated by merging various winglet designs with a constrained aircraft wing. By using computational fluid dynamic (CFD) simulations alongside wind tunnel testing of scaled down 3D-printed models, one can evaluate such forces and determine each respective winglet’s contribution to the total lift and drag forces of the wing. At last, the efficiency of the wing was furtherly determined by evaluating its lift-to-drag ratios with the obtained lift and drag forces. The result from this study showed that the overall efficiency of the wing varied depending on the winglet design, with some designs noticeable more efficient than others according to the CFD-simulations. The shark fin-alike winglet was overall the most efficient design, followed shortly by the famous blended design found in many mid-sized airliners. The worst performing designs were surprisingly the fenced and spiroid designs, which had efficiencies on par with the wing without winglet. 2 Content Abstract 2 Introduction 4 Background 4 1.2 Purpose and structure of the thesis 4 1.3 Literature review 4 Method 9 2.1 Modelling -
Stress Analysis of an Aircraft Fuselage with and Without Portholes Using
cs & Aero ti sp au a n c o e r E e Hadjez and Necib, J Aeronaut Aerospace Eng 2015, 4:1 n A g f i o n Journal of Aeronautics & Aerospace l e DOI: 10.4172/2168-9792.1000138 a e r n i r n u g o J Engineering ISSN: 2168-9792 Research Article Open Access Stress Analysis of an Aircraft Fuselage with and without Portholes using CAD/CAE Process Fayssal Hadjez* and Brahim Necib University of Constantine, Faculty of Science and Technology, Department of Mechanical Engineering, Algeria Abstract The airline industry has been marked by numerous incidents. One of the first, who accompanied the start of operation of the first airliners with jet engines, was directly related to the portholes. Indeed, the banal form of the windows was the source of stress concentrations, which combined with the appearance of micro cracks, caused the explosion in flight of the unit. Since that time, all aircraft openings receive special attention in order to control and reduce their impact on the aircraft structure. In this paper we focus on the representation and quantification of stress concentrations at the windows of a regional jet flying at 40000 feet. To do this, we use a numerical method, similar to what is done at major aircraft manufacturers. The Patran/Nastran software will be used the finite element software to complete our goals. Keywords: Aircraft; Bay; Modeling; Portholes; Fuselage; gradually. It is then necessary to pressurize the cabin to the survival Pressurization; Loads and passenger comfort. However this pressurization is not beneficial to the structure as it involves additional structural loads. -
For Improved Airplane Performance
BLENDED WINGLETS FORFOR IMPROVEDIMPROVED AIRPLANEAIRPLANE PERFORMANCEPERFORMANCE New blended winglets on the Boeing Business Jet and the 737-800 commercial airplane offer operational benefits to customers. Besides giving the airplanes a distinctive appear- ance, the winglets create more efficient flight characteristics in cruise and during takeoff and climbout, which translate into additional range with the same fuel and payload. ROBERT FAYE ROBERT LAPRETE MICHAEL WINTER TECHNICAL DIRECTOR ASSOCIATE TECHNICAL FELLOW PRINCIPAL ENGINEER BOEING BUSINESS JETS AERODYNAMICS TECHNOLOGY STATIC AEROELASTIC LOADS BOEING COMMERCIAL AIRPLANES BOEING COMMERCIAL AIRPLANES BOEING COMMERCIAL AIRPLANES TECHNOLOGY/PRODUCT DEVELOPMENT AERO 16 vertical height of the lifting system (i.e., increasing the length of the TE that sheds the vortices). The winglets increase the spread of the vortices along the TE, creating more lift at the wingtips (figs. 2 and 3). The result is a reduction in induced drag (fig. 4). The maximum benefit of the induced drag reduction depends on the spanwise lift distribution on the wing. Theoretically, for a planar wing, induced drag is opti- mized with an elliptical lift distribution that minimizes the change in vorticity along the span. For the same amount of structural material, nonplanar wingtip 737-800 TECHNICAL CHARACTERISTICS devices can achieve a similar induced drag benefit as a planar span increase; however, new Boeing airplane designs Passengers focus on minimizing induced drag with 3-class configuration Not applicable The 737-800 commercial airplane wingspan influenced by additional 2-class configuration 162 is one of four 737s introduced BBJ TECHNICAL CHARACTERISTICS The Boeing Business Jet design benefits. 1-class configuration 189 in the late 1990s for short- to (BBJ) was launched in 1996 On derivative airplanes, performance Cargo 1,555 ft3 (44 m3) medium-range commercial air- Passengers Not applicable as a joint venture between can be improved by using wingtip Boeing and General Electric. -
Aviation Week & Space Technology
STARTS AFTER PAGE 34 How Air Trvel New Momentum for My Return Smll Nrrowbodies? ™ $14.95 APRIL 20-MAY 3, 2020 SUSTAINABLY Digital Edition Copyright Notice The content contained in this digital edition (“Digital Material”), as well as its selection and arrangement, is owned by Informa. and its affiliated companies, licensors, and suppliers, and is protected by their respective copyright, trademark and other proprietary rights. Upon payment of the subscription price, if applicable, you are hereby authorized to view, download, copy, and print Digital Material solely for your own personal, non-commercial use, provided that by doing any of the foregoing, you acknowledge that (i) you do not and will not acquire any ownership rights of any kind in the Digital Material or any portion thereof, (ii) you must preserve all copyright and other proprietary notices included in any downloaded Digital Material, and (iii) you must comply in all respects with the use restrictions set forth below and in the Informa Privacy Policy and the Informa Terms of Use (the “Use Restrictions”), each of which is hereby incorporated by reference. Any use not in accordance with, and any failure to comply fully with, the Use Restrictions is expressly prohibited by law, and may result in severe civil and criminal penalties. Violators will be prosecuted to the maximum possible extent. You may not modify, publish, license, transmit (including by way of email, facsimile or other electronic means), transfer, sell, reproduce (including by copying or posting on any network computer), create derivative works from, display, store, or in any way exploit, broadcast, disseminate or distribute, in any format or media of any kind, any of the Digital Material, in whole or in part, without the express prior written consent of Informa. -
Flexfloil Shape Adaptive Control Surfaces—Flight Test and Numerical Results
FLEXFLOIL SHAPE ADAPTIVE CONTROL SURFACES—FLIGHT TEST AND NUMERICAL RESULTS Sridhar Kota∗ , Joaquim R. R. A. Martins∗∗ ∗FlexSys Inc. , ∗∗University of Michigan Keywords: FlexFoil, adaptive compliant trailing edge, flight testing, aerostructural optimization Abstract shape-changing control surface technologies has been realized by the ACTE program in which the The U.S Air Force and NASA recently concluded high-lift flaps of the Gulfstream III test aircraft a series of flight tests, including high speed were replaced by a 19-foot spanwise FlexFoilTM (M = 0:85) and acoustic tests of a Gulfstream III variable-geometry control surfaces on each wing, business jet retrofitted with shape adaptive trail- including a 2 ft wide compliant fairings at each ing edge control surfaces under the Adaptive end, developed by FlexSys Inc. The flight tests Compliant Trailing Edge (ACTE) program. The successfully demonstrated the flight-worthiness long-sought goal of practical, seamless, shape- of the variable geometry control surfaces. changing control surface technologies has been Modern aircraft wings and engines have realized by the ACTE program in which the high- reached near-peak levels of efficiency, making lift flaps of the Gulfstream III test aircraft were further improvements exceedingly difficult. The replaced with 23 ft spanwise FlexFoilTM variable next frontier in improving aircraft efficiency is to geometry control surfaces on each wing. The change the shape of the aircraft wing in-flight to flight tests successfully demonstrated the flight- maximize performance under all operating con- worthiness of the variable geometry control sur- ditions. Modern aircraft wing design is a com- faces. We provide an overview of structural and promise between several constraints and flight systems design requirements, test flight envelope conditions with best performance occurring very (including critical design and test points), re- rarely or purely by chance. -
Actuator Saturation Analysis of a Fly-By-Wire Control System for a Delta-Canard Aircraft
DEGREE PROJECT IN VEHICLE ENGINEERING, SECOND CYCLE, 30 CREDITS STOCKHOLM, SWEDEN 2020 Actuator Saturation Analysis of a Fly-By-Wire Control System for a Delta-Canard Aircraft ERIK LJUDÉN KTH ROYAL INSTITUTE OF TECHNOLOGY SCHOOL OF ENGINEERING SCIENCES Author Erik Ljudén <[email protected]> School of Engineering Sciences KTH Royal Institute of Technology Place Linköping, Sweden Saab Examiner Ulf Ringertz Stockholm KTH Royal Institute of Technology Supervisor Peter Jason Linköping Saab Abstract Actuator saturation is a well studied subject regarding control theory. However, little research exist regarding aircraft behavior during actuator saturation. This paper aims to identify flight mechanical parameters that can be useful when analyzing actuator saturation. The studied aircraft is an unstable delta-canard aircraft. By varying the aircraft’s center-of- gravity and applying a square wave input in pitch, saturated actuators have been found and investigated closer using moment coefficients as well as other flight mechanical parameters. The studied flight mechanical parameters has proven to be highly relevant when analyzing actuator saturation, and a simple connection between saturated actuators and moment coefficients has been found. One can for example look for sudden changes in the moment coefficients during saturated actuators in order to find potentially dangerous flight cases. In addition, the studied parameters can be used for robustness analysis, but needs to be further investigated. Lastly, the studied pitch square wave input shows no risk of aircraft departure with saturated elevons during flight, provided non-saturated canards, and that the free-stream velocity is high enough to be flyable. i Sammanfattning Styrdonsmättning är ett välstuderat ämne inom kontrollteorin. -
Stabilizer PLUS 7-Channel Receiver Essential Instructions
Lemon RX Stabilizer PLUS Receiver – Essential Instructions v1.1 Lemon RX Stabilizer PLUS 7-Channel Receiver Essential Instructions Contents Introducing the Lemon StabPLUS ............................................................................................................ 2 Functions ........................................................................................................................................................ 2 Transmitter Requirements .............................................................................................................................. 2 Servos and Power Sources .............................................................................................................................. 3 Setting up the StabPLUS ......................................................................................................................... 4 Installation ...................................................................................................................................................... 4 Binding ............................................................................................................................................................ 5 Setting Failsafe ................................................................................................................................................ 5 Test Flying .............................................................................................................................................. 6 Preparing -
Design, Analysis and Optimization of Folding Wing Mechanism for Effective Utilization of Air Side Area
ISSN (O): 2393-8609 International Journal of Aerospace and Mechanical Engineering Volume 3 – No.5, September 2016 DESIGN, ANALYSIS AND OPTIMIZATION OF FOLDING WING MECHANISM FOR EFFECTIVE UTILIZATION OF AIR SIDE AREA Dishant Kothia Japneet Singh Akanksha Dadhich University of Petroleum and University of Petroleum and University of Petroleum and Energy Studies, Dehradun Energy Studies, Dehradun Energy Studies, Dehradun [email protected] [email protected] akankshadadhich4@gmai om l.com ABSTRACT ground operations altogether, a folding wing design has been This paper aims to suggest a solution for the problem of employed to Boeing 787. disproportionately lesser growth of airside space with respect to growth of passengers/air traffic by using wing folding 2. LITERARY REVIEW mechanism in aircrafts while on ground. A study of air traffic A study was done for past World War-2 era mechanisms, growth was followed by selecting STO-wing mechanism currently used mechanisms in small private aircrafts and also which met with desired requirements. spring loaded mechanisms used in some modern cruise missiles. The naval helicopters and the ship-borne aircraft- Boeing 787-8 Dreamliner was selected as base aircraft as it carriers have been the pioneer, in the sphere of foldable main- met certain criterion and analysis for mechanism was started. planes and tail-planes. Many patents have been created by the Different mechanisms of implementing STO-wing are leading designers and manufacturers. The merits and demand discussed, and calculation for rod-lug mechanism which was of a folding wing mechanism to potentially cease the ill- finally chosen is shown. Its FEM analysis was carried out in effects of traffic growth in aviation industry have paved the ANSYS 14.5 along with mesh sensitivity study. -
Conceptual Design of Self-Expanding/Folding Extremely Large Aspect Ratio Wing Airplane
DOI: 10.13009/EUCASS2017-209 7TH EUROPEAN CONFERENCE FOR AERONAUTICS AND SPACE SCIENCES (EUCASS) Conceptual Design of Self-Expanding/Folding Extremely Large Aspect Ratio Wing Airplane Zhou Xiaopeng* and Chen Haixin* * School of Aerospace Engineering, Tsinghua University Beijing, China Abstract This paper puts forward the idea of self-expanding/folding wing and makes a preliminary conceptual design of extremely large aspect ratio airplane based on this idea. The expanding and folding process in flight is carried out by the movement of the rudder surfaces, the adjustment of distributed propulsion system and the active flight control technology. The preliminary conceptual design and performance analysis indicates that the extremely large aspect ratio airplane based on self-expanding/folding wing can obviously improve the airplane’s airport runway adaptability, take-off and landing performance, keeping a high cruise lift-drag ratio, with acceptable increasing of take-off weight. 1. Introduction 1.1 Requirement for extremely large aspect ratio wing Reducing drag has always been one of the first considerations in aircraft design process. The extremely large aspect ratio wing has great advantages in cutting down induced drag, which leading to widely applications in glider, long- endurance UAV, high-altitude launch aircraft and other aircrafts. Finding out a suitable configuration to carry out the extremely large aspect ratio wing, keeping the advantages and overcoming the shortcomings, is the focus of high- altitude long-endurance aircraft and other similar aircrafts design. 1.2 Implement methods of extremely large aspect ratio wing airplane The increasing wingspan of conventional cantilever wings is limited by the conditions for take-off and landing of airport runways, poor flight conditions of lower atmosphere owing to unstable airflow, structural strength and rigidity of aircraft, and flight handling qualities.