Wilkinson Matthew T
Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK.
J Exp Biol. 2007 May;210(Pt 10):1663-71. doi: 10.1242/jeb.000307.
Pterosaur wings bore a striking resemblance to sails, having a bony spar at the leading edge, formed by the forelimb and one enormously elongated digit, and an elastic wing membrane. Such simple wings would be expected to have performed badly due to excessive deformation, membrane flutter and poor control characteristics. Here I discuss how certain anatomical features, specifically a forewing membrane in the inner part of the wing and a system of fibres embedded in the distal part, may have countered these shortcomings. The forewing, supported by the unique pteroid bone, would have reduced the wings' geometric twist, and has been shown in wind tunnel tests to improve membrane stability at low angles of attack and dramatically increase the maximum lift coefficient at high angles of attack. The function of the fibres is poorly understood, but it is suggested that they improved membrane stability and optimised twist nearer the wingtips.
翼龙的翅膀与帆极为相似，其前缘有一根骨质梁，由前肢和一根极度延长的手指构成，还有一层弹性翼膜。由于过度变形、膜的颤动以及控制特性不佳，这样简单的翅膀预计表现很差。在此我将讨论某些解剖学特征，特别是翅膀内侧的前翼膜以及嵌入远端部分的纤维系统，是如何克服这些缺点的。由独特的翼骨支撑的前翼，会减少翅膀的几何扭转，并且风洞试验表明，它能在低攻角时提高膜的稳定性，在高攻角时显著增加最大升力系数。纤维的功能尚不清楚，但有人认为它们提高了膜的稳定性，并使靠近翼尖处的扭转得以优化。
