Video Clip of Crane 814 Climbing and Then Gliding in the "Sweet Spot
Joe Duff's Photo of Two Cranes Glidig Close to the Wing's Vortex ("Sweet Spot")http://www.learner.org/jnorth/images/graphics/crane/SweetSpot_JDuff.jpg
Richard van Heuvelen's Photo of Gliding
Mark Chenoweth's Photo of Cranes in Formation Behind Chris (note color of wing edge)
How Does the Trike Help the Cranes in Flight?