On my 50MY only the center section opened. It was really heavy, very difficult to reach to open, and was held open only by a slotted bar on each side with screw retainers. I enjoyed the ventilation when open but it was so heavy and the farther bar was so difficult to reach to tighten that I seldom opened the window. It also always leaked a little. Then I removed the troublesome air-operated windshield wipers and replaced them with a clear-view rotating screen which doubled the weight and weakened the glass with its large cut out and drilled mounting bolts. I realized that if the open window ever bounced out of its slots it would slam shut and not only shatter the glass but the screen motor would probably take out the compass as well. When the time came for new window frames I decided to quit while I was ahead and changed to a non-opening frame. The original set up was a disaster waiting to happen.
In good weather we generally have all the windows and doors open along with the bow hatch. If too hot, mosquito-ie or rainy there is always the air conditioner.