Excellent finding, Brian - thank you. I did not know about the straight wing vortex. Amazing that the Auster and Connie had that.
I assume the BAC Lightning produced significant l. e. vortices since a lot of manoeuvring in that a/c was in varying degrees of buffet, including the finals turn in the circuit and the well-known 'rotation' take-off which used to go right throught the stalling angle (and still fly!). The secret was to have no yaw................
