Natural panpipes on Lonscale Fell

 

The wind was blowing across two open ended gate suspensions on Lonscale Fell. This produced two different tones which blew alternately as the wind gusted. Suppose B was about 120cm long. Given a stationary wave with antinodes at each end and a node in the middle, the wavelength is 2.40m. This gives frequency = speed of sound/wavelength = 340/2.4 = 140Hz to 2sf. That is low but audible. The broken shorter pipe is about 50cm long giving a higher tone of 340Hz.