Turning downwind in a stiff wind relative to the aircraft's indicated IAS, be it in a Mallard or a 747 is akin to a windshear event. Simple inertia. A320 I flew, somewhat between those two weights of aircraft, on full automatics gave me an 'airspeed low' warning doing just that several times in my short time on the plastic fantastic. Gentlemen and ladies this is real threat, forget CRM threats, even helicopters have the same problem. Not saying this is the cause of the sadly fatal accident-simply commenting on a previous poster.