.....In the 172s I fly the window can be open at any normal speed. I fly all the time with the windows open and there is no difference with how the aircraft handles. ....
Not a 172 but I do it all the time in my 150. I flew with bad latches for quite a while too & got used to them coming open often. Have even opened both doors & used them to control the airplane. Works pretty good. If all the controls except the trim fail I think I could get it down on the airport & walk away. Maybe even still have an airplane!
However, if someone opened a door, then the change in performance would be immediately noticeable since you are changing the surface area of the aircraft exposed to the relative wind. You would have to make a much larger control surface and speed correction to account for your newly found parasite drag.
Check your flight manual for the max speed the windows maybe opened... I install Bubble windows with a placard reading "129 Knots max. speed with window open".
Quote from: David B on November 04, 2009, 04:43:34 PM.....In the 172s I fly the window can be open at any normal speed. I fly all the time with the windows open and there is no difference with how the aircraft handles. .... No offense, but I call BS on this one. During one of our rare heat waves a few months ago, I flew with the pilot's window open all the way up against the wing. There was a noticable yaw factor, & (strangely enough) it yawed away from the side with the open window, not toward it. Maybe with both windows open it would even out, but that's not the scenario in the original post. And landing is the phase of flight when I'd least want to experience uncommanded (and unwanted) changes in handling.Eric