A sooner-initiated turn from the downwind of runway 6 would have put the plane on the ground beyond the runway 6 threshhold. With two miles of pavement available, why fly a pattern that offers ANY chance of landing short of the threshhold?
Better yet, a simple 90-degree left turn from the left downwind of runway 6 would have put the aircraft on final for runway 15 - ABOVE the asphalt, and with half of the altitude loss of making a 180-degree turn.