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Aeroelasticity

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of one component can induce flutter in an apparently unrelated aerodynamic component. At its mildest, this can appear as a "buzz" in the aircraft structure, but at its most violent, it can develop uncontrollably with great speed and cause serious damage to the aircraft or lead to its destruction, as
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is a high-frequency instability, caused by airflow separation or shock wave oscillations from one object striking another. It is caused by a sudden impulse of load increasing. It is a random forced vibration. Generally it affects the tail unit of the aircraft structure due to air flow downstream of
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Divergence occurs when a lifting surface deflects under aerodynamic load in a direction which further increases lift in a positive feedback loop. The increased lift deflects the structure further, which eventually brings the structure to the point of divergence. Unlike flutter, which is another
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Control surface reversal is the loss (or reversal) of the expected response of a control surface, due to deformation of the main lifting surface. For simple models (e.g. single aileron on an Euler-Bernoulli beam), control reversal speeds can be derived analytically as for torsional divergence.
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structure. Dynamic instability can occur involving pitch and yaw degrees of freedom of the propeller and the engine supports leading to an unstable precession of the propeller. Failure of the engine supports led to whirl flutter occurring on two Lockheed L-188 Electra aircraft, in 1959 on
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Structures exposed to aerodynamic forces—including wings and aerofoils, but also chimneys and bridges—are generally designed carefully within known parameters to avoid flutter. Blunt shapes, such as chimneys, can give off a continuous stream of vortices known as a
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In water the mass ratio of the pitch inertia of the foil to that of the circumscribing cylinder of fluid is generally too low for binary flutter to occur, as shown by explicit solution of the simplest pitch and heave flutter stability determinant.
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defined aeroelasticity as "the study of the mutual interaction that takes place within the triangle of the inertial, elastic, and aerodynamic forces acting on structural members exposed to an airstream, and the influence of this study on design".
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The model can be used to predict the flutter margin and, if necessary, test fixes to potential problems. Small carefully chosen changes to mass distribution and local structural stiffness can be very effective in solving aeroelastic problems.
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bomber during a flight in 1916, when it suffered a violent tail oscillation, which caused extreme distortion of the rear fuselage and the elevators to move asymmetrically. Although the aircraft landed safely, in the subsequent investigation
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In complex structures where both the aerodynamics and the mechanical properties of the structure are not fully understood, flutter can be discounted only through detailed testing. Even changing the mass distribution of an aircraft or the
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and eventual failure. "Net damping" can be understood as the sum of the structure's natural positive damping and the negative damping of the aerodynamic force. Flutter can be classified into two types:
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was consulted. One of his recommendations was that left and right elevators should be rigidly connected by a stiff shaft, which was to subsequently become a design requirement. In addition, the
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Aeroelasticity involves not just the external aerodynamic loads and the way they change but also the structural, damping and mass characteristics of the aircraft. Prediction involves making a
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aeroelastic problem, instead of irregular oscillations, divergence causes the lifting surface to move in the same direction and when it comes to point of divergence the structure deforms.
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Aircraft are prone to aeroelastic effects because they need to be lightweight while enduring large aerodynamic loads. Aircraft are designed to avoid the following aeroelastic problems:
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regime, dominated by moving shock waves. Avoiding flutter is mission-critical for aircraft that fly through transonic Mach numbers. The role of shock waves was first analyzed by
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or other control surfaces, in which these control surfaces reverse their usual functionality (e.g., the rolling direction associated with a given aileron moment is reversed).
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Aeroelasticity problems can be prevented by adjusting the mass, stiffness or aerodynamics of structures which can be determined and verified through the use of calculations,
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and were solved largely by trial-and-error and ad hoc stiffening of the wing. The first recorded and documented case of flutter in an aircraft was that which occurred to a
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flight research program to investigate the potential of aerodynamically twisting flexible wings to improve maneuverability of high-performance aircraft at transonic and
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The adequacy of comparison between flutter in aircraft aerodynamics and Tacoma Narrows Bridge case is discussed and disputed in Yusuf K. Billah, Robert H. Scanian,
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which details the processes used in solving and verifying aeroelastic problems along with standard examples that can be used to test numerical solutions.
902:= 0 corresponds to the point of torsional divergence. For given structural parameters, this will correspond to a single value of free-stream velocity 1961: 677: 937:
Dynamic aeroelasticity studies the interactions among aerodynamic, elastic, and inertial forces. Examples of dynamic aeroelastic phenomena are:
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where control activation produces an opposite aerodynamic moment that reduces, or in extreme cases reverses, the control effectiveness; and
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is a special case of flutter involving the aerodynamic and inertial effects of a rotating propeller and the stiffness of the supporting
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Garrick, I. E. and Reed W. H., "Historical development of aircraft flutter", Journal of Aircraft, vol. 18, pp. 897–912, Nov. 1981.
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Tang, D. M. (2004). "Effects of geometric structural nonlinearity on flutter and limit cycle oscillations of high-aspect-ratio wings".
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is a phenomenon in which the elastic twist of the wing suddenly becomes theoretically infinite, typically causing the wing to fail.
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In some cases, automatic control systems have been demonstrated to help prevent or limit flutter-related structural vibration.
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Golestani, A.; et al. (2015). "An experimental study of buffet detection on supercritical airfoils in transonic regime".
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started a course "Elasticity applied to Aeronautics". After teaching the course for one term, Kármán passed it over to
417:’ is the aerodynamic moment per unit length. Under a simple lift forcing theory the aerodynamic moment is of the form 1887: 1872: 1386: 423: 1689:
Farmer, M. G.; Hanson, P. W. (1976). "Comparison of Super-critical and Conventional Wing Flutter Characteristics".
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published a theory of wing divergence, leading to much further theoretical research on the subject. The term
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of the aircraft structure. The model also includes details of applied aerodynamic forces and how they vary.
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Collar, A. R., "The first fifty years of aeroelasticity", Aerospace, vol. 5, no. 2, pp. 12–20, 1978.
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of the aircraft as a series of masses connected by springs and dampers which are tuned to represent the
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Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering
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where the aerodynamic forces increase the twist of a wing which further increases forces;
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Ashley, Holt (1980). "Role of Shocks in the 'Sub-Transonic' Flutter Phenomenon".
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Time lapsed film of Active Aeroelastic Wing (AAW) Wing loads test, December, 2002
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Video of the Tacoma Narrows Bridge being destroyed through aeroelastic fluttering
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are typically wrapped around chimneys to stop the formation of these vortices.
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which is uncontained vibration that can lead to the destruction of an aircraft.
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The boundary conditions for a clamped-free beam (i.e., a cantilever wing) are
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published in 1906. Problems with torsional divergence plagued aircraft in the
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Control reversal can be used to aerodynamic advantage, and forms part of the
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flow. The study of aeroelasticity may be broadly classified into two fields:
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F/A-18A (now X-53) Active Aeroelastic Wing (AAW) flight test, December, 2002
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between the body's deflection and the force exerted by the fluid flow. In a
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is a dynamic instability of an elastic structure in a fluid flow, caused by
1541:"Binary Flutter as an Oscillating Windmill – Scaling & Linear Analysis" 1466: 1299: 757:{\displaystyle \theta |_{y=0}=\left.{\frac {d\theta }{dy}}\right|_{y=L}=0,} 74: 1137: 1333: 1191: 1123: 1078: 175: 50: 1962:"Low-Speed Buffet: High-Altitude, Transonic Training Weakness Continues" 1698: 1979: 1588:"Resonance, Tacoma Bridge failure, and undergraduate physics textbooks" 1219: 1097:
Buffeting of the fin caused by the breakdown of the vortex on the NASA
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In an aeroplane, two significant static aeroelastic effects may occur.
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Collar, A. R. (1978). "The first fifty years of aeroelasticity".
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Mass balances protruding from an aileron used to suppress flutter
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can be used to determine the speed at which flutter will occur.
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Methods of predicting flutter in linear structures include the
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Visual demonstration of flutter which destroys an RC aircraft
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fighter aircraft in the early 1940s. Famously, the original
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Interactions among inertial, elastic, and aerodynamic forces
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Aircraft Accident Investigation at ARL-The first 50 years
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1931 Transcontinental & Western Air Fokker F-10 crash
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Divergence can be understood as a simple property of the
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divergence). An early scientific work on the subject was
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forces occurring while an elastic body is exposed to a
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Introduction to Structural Dynamics and Aeroelasticity
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Introduction to Structural Dynamics and Aeroelasticity
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NACA Technical Reports – NASA Langley Research Center
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Bisplinghoff, R. L.; Ashley, H.; Halfman, H. (1996).
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was destroyed as a result of aeroelastic fluttering.
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Aeroelasticity Branch – NASA Langley Research Center
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was destroyed as a result of aeroelastic fluttering.
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The Aeroelasticity Group – Texas A&M University
1222:speeds, with traditional control surfaces such as 867: 756: 661:{\displaystyle \lambda ^{2}=C{\frac {U^{2}}{GJ}}.} 660: 596: 478: 386: 127:is usually eliminated by the careful placement of 1925:Introduction to Aircraft Aeroelasticity and Loads 1863:Bisplinghoff, R. L., Ashley, H. and Halfman, H., 1226:and leading-edge flaps used to induce the twist. 1194:oscillation (LCO), and methods from the study of 1122:Computing separation from trailing edge based on 306:. For example, modelling the airplane wing as an 77:response of an elastic body to a fluid flow, and 2011: 1402: 1400: 1398: 977:, in which the net damping decreases gradually. 1895:An Introduction to the Theory of Aeroelasticity 1643:"Lessons Learned From Civil Aviation Accidents" 1268: 501:is the initial angle of attack. This yields an 479:{\displaystyle M'=CU^{2}(\theta +\alpha _{0}),} 1372: 1370: 1590:; Am. J. Phys. 59(2), 118–124, February 1991. 1395: 273:is a phenomenon occurring only in wings with 1688: 1533: 1004:, which can induce structural oscillations. 172:Theory of the Stability of a Rigid Aeroplane 1840:Defence Science and Technology Organisation 1582: 1580: 1367: 1068: 1044: 292:Equations for divergence of a simple beam 1706: 1619:"Review of propeller-rotor whirl flutter" 1527:Aeroelasticity: Lecture 6: Flight testing 1025:in 1959, or the prototypes for Finland's 932: 1938:Hoque, M. E., "Active Flutter Control", 1849:from the original on September 27, 2019. 1577: 1499: 1497: 1495: 1136: 1092: 983: 497:is the free-stream fluid velocity, and α 409:is the torsional stiffness of the beam, 260: 29: 1559: 1456: 1441:Airplane Structural Analysis and Design 14: 2012: 1830: 1661: 1479: 1190:, flutter is usually interpreted as a 1132: 1112:The methods for buffet detection are: 1036: 53:studying the interactions between the 1960:Patrick R. Veillette (Aug 23, 2018). 1524:G. Dimitriadis, University of Liège, 1492: 134:The synthesis of aeroelasticity with 1795: 1616: 1119:Pressure divergence at trailing edge 1063:Northwest Orient Airlines Flight 710 868:{\displaystyle \theta =\alpha _{0}.} 1818:10.1016/j.jfluidstructs.2003.10.007 1503:Hodges, D. H. and Pierce, A., 1128:Normal force fluctuating divergence 913: 24: 1966:Business & Commercial Aviation 1857: 405:is the elastic twist of the beam, 25: 2051: 1973: 1923:Wright, J. R. and Cooper, J. E., 1880:A Modern Course on Aeroelasticity 1073:Flow is highly non-linear in the 1250: 1231: 890:, with arbitrary integer number 1985:DLR Institute of Aeroelasticity 1940:LAP Lambert Academic Publishing 1824: 1789: 1758: 1723: 1682: 1655: 1635: 1610: 1593: 1281:Propeller whirl flutter of the 1908:Hodges, D. H. and Pierce, A., 1798:Smart Materials and Structures 1518: 1473: 1450: 1430: 1414: 859: 850: 841: 829: 820: 811: 802: 793: 686: 503:ordinary differential equation 470: 451: 13: 1: 1990:National Aerospace Laboratory 1617:Reed, Wilmer H. (July 1967). 1360: 280: 2005:NASA Aeroelasticity Handbook 1354:X-53 Active Aeroelastic Wing 1298:Body freedom flutter of the 1269:Notable aeroelastic failures 1116:Pressure coefficient diagram 1088: 220:Royal Aircraft Establishment 189:National Physical Laboratory 38:in a wind tunnel for flutter 7: 1306: 1019:Northwest Airlines Flight 2 401:is the spanwise dimension, 73:dealing with the static or 34:NASA testing a scale model 10: 2056: 940: 917: 767:which yields the solution 313:, the uncoupled torsional 153: 1461:. New York: McGraw-Hill. 1459:Elasticity in Engineering 1145:In the period 1950–1970, 142:, and its synthesis with 1968:. Aviation Week Network. 1744:10.1177/0954410014531743 1349:Vortex-induced vibration 1206:These videos detail the 1201: 1151:Manual on Aeroelasticity 1069:Transonic aeroelasticity 413:is the beam length, and 231:aeronautical engineering 81:dealing with the body's 1867:. Dover Science, 1996, 1457:Sechler, E. E. (1952). 1314:Adaptive compliant wing 1208:Active Aeroelastic Wing 1162:dynamic characteristics 1083:Langley Research Center 1050:Propeller whirl flutter 1045:Propeller whirl flutter 302:(s) governing the wing 1831:Kepert, J. L. (1993). 1551:. 2013. Archived from 1439:and L. G. Dunn (1942) 1283:Lockheed L-188 Electra 1142: 1102: 996: 958:simple harmonic motion 933:Dynamic aeroelasticity 927:Kaman servo-flap rotor 869: 758: 662: 598: 480: 388: 254:Arthur Roderick Collar 229:In the development of 158:The second failure of 117:ground vibration tests 79:dynamic aeroelasticity 39: 2030:Aerospace engineering 1408:"AeroSociety Podcast" 1329:Mathematical modeling 1319:Aerospace engineering 1276:Tacoma Narrows Bridge 1140: 1096: 1061:and again in 1960 on 1031:Tacoma Narrows Bridge 994: 870: 759: 663: 599: 481: 389: 300:differential equation 261:Static aeroelasticity 210:itself was coined by 121:flight flutter trials 71:static aeroelasticity 33: 2040:Elasticity (physics) 2025:Aircraft wing design 1778:on December 14, 2019 1437:Ernest Edwin Sechler 1339:Parker Variable Wing 1324:Kármán vortex street 1002:Kármán vortex street 878:As can be seen, for 774: 678: 614: 512: 424: 324: 311:Euler–Bernoulli beam 243:Ernest Edwin Sechler 226:in the early 1930s. 140:aerothermoelasticity 1912:, Cambridge, 2002, 1810:2004JFS....19..291T 1699:10.2514/6.1976-1560 1664:Journal of Aircraft 1507:, Cambridge, 2002, 1425:The Wind and Beyond 1421:Theodore von Kármán 1133:Prediction and cure 1037:Aeroservoelasticity 239:Theodore von Kármán 148:aeroservoelasticity 1287:Braniff Flight 542 1158:mathematical model 1143: 1103: 1059:Braniff Flight 542 1023:Braniff Flight 542 997: 865: 754: 658: 594: 493:is a coefficient, 476: 384: 315:equation of motion 180:Handley Page O/400 40: 1948:978-3-8383-6851-1 1942:, Germany, 2010, 1933:978-0-470-85840-0 1918:978-0-521-80698-5 1903:978-0-486-67871-9 1513:978-0-521-80698-5 1381:. 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H., 1860: 1858:Further reading 1855: 1854: 1846: 1835: 1829: 1825: 1794: 1790: 1781: 1779: 1775: 1768: 1764: 1763: 1759: 1728: 1724: 1691:NASA Tm X-72837 1687: 1683: 1676:10.2514/3.57891 1660: 1656: 1647: 1645: 1641: 1640: 1636: 1627: 1625: 1621: 1615: 1611: 1603: 1599: 1598: 1594: 1585: 1578: 1566: 1564: 1560: 1539: 1538: 1534: 1523: 1519: 1502: 1493: 1478: 1474: 1455: 1451: 1435: 1431: 1419: 1415: 1406: 1405: 1396: 1389: 1375: 1368: 1363: 1358: 1344:Vortex shedding 1309: 1271: 1264: 1261: 1251: 1246: 1243: 1232: 1204: 1135: 1091: 1071: 1047: 1039: 984: 943: 935: 922: 916: 898:) is infinite. 787: 783: 775: 772: 771: 733: 719: 711: 709: 706: 705: 690: 685: 684: 679: 676: 675: 645: 639: 635: 633: 621: 617: 615: 612: 611: 585: 581: 575: 571: 556: 552: 540: 536: 532: 522: 518: 517: 515: 513: 510: 509: 500: 464: 460: 445: 441: 427: 425: 422: 421: 373: 358: 354: 350: 340: 336: 335: 333: 325: 322: 321: 283: 263: 176:First World War 156: 28: 23: 22: 15: 12: 11: 5: 2053: 2043: 2042: 2037: 2032: 2027: 2022: 2008: 2007: 2002: 1997: 1992: 1987: 1982: 1975: 1974:External links 1972: 1971: 1970: 1957: 1954: 1951: 1936: 1927:, Wiley 2007, 1921: 1906: 1891: 1876: 1865:Aeroelasticity 1859: 1856: 1853: 1852: 1823: 1804:(3): 291–306. 1788: 1757: 1738:(2): 312–322. 1722: 1681: 1670:(3): 187–197. 1654: 1634: 1609: 1592: 1576: 1558: 1555:on 2014-10-29. 1532: 1517: 1491: 1472: 1449: 1429: 1413: 1394: 1387: 1379:Aeroelasticity 1365: 1364: 1362: 1359: 1357: 1356: 1351: 1346: 1341: 1336: 1331: 1326: 1321: 1316: 1310: 1308: 1305: 1304: 1303: 1296: 1290: 1279: 1270: 1267: 1266: 1265: 1262: 1249: 1247: 1244: 1230: 1203: 1200: 1149:developed the 1134: 1131: 1130: 1129: 1126: 1120: 1117: 1090: 1087: 1070: 1067: 1046: 1043: 1038: 1035: 942: 939: 934: 931: 918:Main article: 915: 912: 909: 908: 876: 875: 864: 861: 858: 855: 852: 849: 846: 843: 840: 837: 834: 831: 828: 825: 822: 819: 816: 813: 810: 807: 804: 801: 798: 795: 790: 786: 782: 779: 765: 764: 753: 750: 747: 742: 739: 736: 731: 725: 722: 717: 714: 708: 704: 699: 696: 693: 688: 683: 669: 668: 657: 651: 648: 642: 638: 632: 629: 624: 620: 605: 604: 593: 588: 584: 578: 574: 570: 567: 564: 559: 555: 551: 543: 539: 535: 530: 525: 521: 498: 487: 486: 475: 472: 467: 463: 459: 456: 453: 448: 444: 440: 437: 433: 430: 395: 394: 383: 379: 376: 372: 369: 361: 357: 353: 348: 343: 339: 332: 329: 294: 293: 282: 279: 262: 259: 216:Alfred Pugsley 208:aeroelasticity 160:Samuel Langley 155: 152: 144:control theory 136:thermodynamics 113: 112: 106: 100: 43:Aeroelasticity 26: 9: 6: 4: 3: 2: 2052: 2041: 2038: 2036: 2033: 2031: 2028: 2026: 2023: 2021: 2018: 2017: 2015: 2006: 2003: 2001: 1998: 1996: 1993: 1991: 1988: 1986: 1983: 1981: 1978: 1977: 1967: 1963: 1958: 1955: 1952: 1949: 1945: 1941: 1937: 1934: 1930: 1926: 1922: 1919: 1915: 1911: 1907: 1904: 1900: 1896: 1893:Fung, Y. C., 1892: 1889: 1888:90-286-0057-4 1885: 1881: 1877: 1874: 1873:0-486-69189-6 1870: 1866: 1862: 1861: 1845: 1841: 1834: 1827: 1819: 1815: 1811: 1807: 1803: 1799: 1792: 1774: 1767: 1761: 1753: 1749: 1745: 1741: 1737: 1733: 1726: 1718: 1714: 1709: 1704: 1700: 1696: 1692: 1685: 1677: 1673: 1669: 1665: 1658: 1644: 1638: 1620: 1613: 1602: 1596: 1589: 1583: 1581: 1573: 1569: 1562: 1554: 1550: 1546: 1542: 1536: 1529: 1528: 1521: 1514: 1510: 1506: 1500: 1498: 1496: 1487: 1483: 1476: 1468: 1464: 1460: 1453: 1446: 1442: 1438: 1433: 1426: 1422: 1417: 1409: 1403: 1401: 1399: 1390: 1388:0-486-69189-6 1384: 1380: 1373: 1371: 1366: 1355: 1352: 1350: 1347: 1345: 1342: 1340: 1337: 1335: 1332: 1330: 1327: 1325: 1322: 1320: 1317: 1315: 1312: 1311: 1301: 1297: 1294: 1291: 1288: 1284: 1280: 1277: 1274:The original 1273: 1272: 1248: 1229: 1228: 1227: 1225: 1221: 1217: 1213: 1209: 1199: 1197: 1193: 1189: 1184: 1182: 1178: 1174: 1169: 1165: 1163: 1159: 1154: 1152: 1148: 1139: 1127: 1125: 1121: 1118: 1115: 1114: 1113: 1110: 1107: 1100: 1095: 1086: 1084: 1080: 1076: 1066: 1064: 1060: 1055: 1051: 1042: 1034: 1032: 1028: 1024: 1020: 1015: 1009: 1007: 1003: 982: 978: 976: 972: 967: 963: 959: 955: 954:linear system 951: 947: 938: 930: 928: 921: 907: 905: 901: 897: 893: 889: 885: 881: 862: 856: 853: 847: 844: 838: 835: 832: 826: 823: 817: 814: 808: 805: 799: 796: 788: 784: 780: 777: 770: 769: 768: 751: 748: 745: 740: 737: 734: 729: 723: 720: 715: 712: 702: 697: 694: 691: 681: 674: 673: 672: 655: 649: 646: 640: 636: 630: 627: 622: 618: 610: 609: 608: 591: 586: 582: 576: 572: 568: 565: 562: 557: 553: 549: 541: 537: 533: 528: 523: 519: 508: 507: 506: 504: 496: 492: 473: 465: 461: 457: 454: 446: 442: 438: 435: 431: 428: 420: 419: 418: 416: 412: 408: 404: 400: 381: 377: 374: 370: 367: 359: 355: 351: 346: 341: 337: 330: 327: 320: 319: 318: 316: 312: 309: 305: 301: 296: 295: 291: 290: 287: 278: 276: 272: 268: 258: 255: 250: 248: 244: 240: 236: 232: 227: 225: 221: 217: 213: 209: 205: 204:Hans Reissner 200: 198: 194: 190: 186: 181: 177: 173: 169: 165: 161: 151: 149: 145: 141: 137: 132: 130: 129:mass balances 126: 123:. Flutter of 122: 118: 110: 107: 104: 101: 98: 95: 94: 93: 90: 88: 84: 80: 76: 72: 68: 64: 60: 56: 52: 48: 44: 37: 32: 19: 2020:Aerodynamics 1965: 1924: 1909: 1894: 1879: 1864: 1826: 1801: 1797: 1791: 1780:. Retrieved 1773:the original 1760: 1735: 1731: 1725: 1690: 1684: 1667: 1663: 1657: 1646:. Retrieved 1637: 1626:. Retrieved 1612: 1595: 1561: 1553:the original 1548: 1544: 1535: 1526: 1520: 1504: 1485: 1481: 1475: 1458: 1452: 1432: 1424: 1416: 1378: 1300:GAF Jindivik 1205: 1185: 1180: 1176: 1172: 1170: 1166: 1155: 1150: 1144: 1111: 1104: 1072: 1049: 1048: 1040: 1010: 998: 979: 975:soft flutter 974: 971:hard flutter 970: 945: 944: 936: 923: 903: 899: 895: 891: 887: 883: 879: 877: 766: 670: 606: 505:of the form 494: 490: 488: 414: 410: 406: 402: 398: 396: 297: 284: 270: 266: 264: 251: 228: 207: 201: 171: 168:George Bryan 157: 147: 146:is known as 139: 138:is known as 133: 128: 120: 116: 114: 108: 102: 96: 91: 89:) response. 78: 75:steady state 70: 42: 41: 1427:, page 155. 1334:Oscillation 1192:limit cycle 1124:Mach number 1101:F/A-18 wing 1079:Holt Ashley 224:Farnborough 197:Arthur Fage 87:vibrational 85:(typically 63:aerodynamic 51:engineering 2014:Categories 1838:(Report). 1782:2019-12-14 1648:2019-12-14 1628:2019-11-15 1361:References 1220:supersonic 1210:two-phase 1181:p-k method 1109:the wing. 960:—zero net 304:deflection 281:Divergence 267:Divergence 97:divergence 1752:110673867 1717:120598336 1482:Aerospace 1216:Air Force 1106:Buffeting 1089:Buffeting 1075:transonic 1027:VL Myrsky 1021:in 1938, 1014:stiffness 854:− 845:λ 839:⁡ 824:λ 818:⁡ 806:λ 800:⁡ 785:α 778:θ 716:θ 682:θ 619:λ 583:α 573:λ 569:− 563:θ 554:λ 529:θ 462:α 455:θ 371:− 347:θ 308:isotropic 252:In 1947, 247:textbooks 202:In 1926, 164:torsional 18:Buffeting 1875:, 880 p. 1844:Archived 1488:: 12–20. 1307:See also 1224:ailerons 1179:and the 1177:k-method 1173:p-method 929:design. 432:′ 378:′ 275:ailerons 55:inertial 1806:Bibcode 1572:YouTube 1467:2295857 1423:(1967) 1054:nacelle 1006:Strakes 962:damping 946:Flutter 941:Flutter 235:Caltech 222:(RAE), 218:at the 154:History 109:flutter 83:dynamic 59:elastic 47:physics 1946:  1931:  1916:  1901:  1886:  1871:  1750:  1715:  1624:. Nasa 1511:  1465:  1385:  1302:drone. 1175:, the 894:, tan( 607:where 489:where 397:where 61:, and 1847:(PDF) 1836:(PDF) 1776:(PDF) 1769:(PDF) 1748:S2CID 1713:S2CID 1622:(PDF) 1604:(PDF) 1484:. 2. 1443:from 1202:Media 1147:AGARD 886:/2 + 67:fluid 1944:ISBN 1929:ISBN 1914:ISBN 1899:ISBN 1884:ISBN 1869:ISBN 1509:ISBN 1463:OCLC 1383:ISBN 1212:NASA 1186:For 1099:HARV 214:and 195:and 119:and 49:and 1814:doi 1740:doi 1736:229 1703:hdl 1695:doi 1672:doi 1570:on 1285:on 1017:in 836:cos 815:sin 797:tan 317:is 233:at 170:'s 2016:: 1964:. 1882:. 1842:. 1812:. 1802:19 1800:. 1746:. 1734:. 1711:. 1701:. 1693:. 1668:17 1666:. 1579:^ 1549:37 1547:. 1543:. 1494:^ 1397:^ 1369:^ 1183:. 1085:. 1065:. 896:λL 888:nπ 882:= 880:λL 407:GJ 237:, 199:. 150:. 131:. 57:, 1950:. 1935:. 1920:. 1905:. 1890:. 1820:. 1816:: 1808:: 1785:. 1754:. 1742:: 1719:. 1705:: 1697:: 1678:. 1674:: 1651:. 1631:. 1606:. 1574:. 1530:. 1515:. 1486:5 1469:. 1447:. 1410:. 1391:. 1295:. 1289:. 1214:- 904:U 900:n 892:n 884:π 863:. 860:] 857:1 851:) 848:y 842:( 833:+ 830:) 827:y 821:( 812:) 809:L 803:( 794:[ 789:0 781:= 752:, 749:0 746:= 741:L 738:= 735:y 730:| 724:y 721:d 713:d 703:= 698:0 695:= 692:y 687:| 656:. 650:J 647:G 641:2 637:U 631:C 628:= 623:2 592:, 587:0 577:2 566:= 558:2 550:+ 542:2 538:y 534:d 524:2 520:d 499:0 495:U 491:C 474:, 471:) 466:0 458:+ 452:( 447:2 443:U 439:C 436:= 429:M 415:M 411:L 403:θ 399:y 382:, 375:M 368:= 360:2 356:y 352:d 342:2 338:d 331:J 328:G 20:)

Index

Buffeting

Lockheed Electra
physics
engineering
inertial
elastic
aerodynamic
fluid
steady state
dynamic
vibrational
control surfaces
thermodynamics
control theory
Samuel Langley
torsional
George Bryan
First World War
Handley Page O/400
F. W. Lanchester
National Physical Laboratory
Leonard Bairstow
Arthur Fage
Hans Reissner
Harold Roxbee Cox
Alfred Pugsley
Royal Aircraft Establishment
Farnborough
aeronautical engineering

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