The wing has a curved planform: both the leading and trailing edges of the wing are described by curved lines.
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Lombardi, "The effects of the planform shape on drag polar curves of wings: fluid-structure interaction analyses results," in STAR Global Conference 2013, Orlando, Fla, USA, March 2013.
A campaign of dynamic fluid structure interaction analyses was carried out to investigate the effects of the planform on the stability properties of high aspect ratio wings.
Previous studies have demonstrated that a curved planform wing reduces the drag coefficient.
The results of the present study demonstrate that from a dynamic point of view (i) a curved planform wing shows an excellent performance also in fully subsonic flight conditions and (ii) in the transonic regime, for a curved planform wing, shock phenomena are less critical compared to those occurring on a conventional swept wing.
This is an interesting result, because, for fully subsonic flight conditions, with all other design parameters fixed, the planform shape of the curved wing leads to an important increase in wing flutter speed.
Figures 13 and 14 highlight that, also in Case 2 (i.e., a fully transonic regime), the curved planform provides increases in flutter speed.