“…Sectional imaging involving either chordwise or spanwise planes, or a combination of them, has been used by Birch & Dickinson (2001), Birch, Dickson & Dickinson (2004), Ansari et al (2009), Jones, Ford & Babinsky (2011, Ozen & Rockwell (2012) and Wojcik & Buchholz (2012). Volume imaging with interpretation of selected sections has been employed by Liu et al (1998), Poelma, Dickson & Dickinson (2006), Aono, Liang & Liu (2008), Lu & Shen (2008), Kim & Gharib (2010) and Carr et al (2012). These investigations extend over a wide range of Reynolds number, and reveal a number of important phenomena, including a coherent and stable (LEV), possible occurrence of vortex breakdown, the distribution and magnitude of spanwise velocity and the history of the lift acting on the wing.…”