At 09:09 AM 1/4/2016, you wrote: >I know there is a 130 miles an hour speed brake with wood screws. >That is what I was thinking when I initially posted. +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
I've seen too many screws on aircraft that loosen with vibration over time. They get loose, enlarge the hole, etc. My firewall cowl brackets have a single 3/16" bolt in the center and then small wood screws to keep them from rotating. ( https://dl.dropboxusercontent.com/u/32133949/IMG_8083.jpg and then enlarge ) One or two small screws are lighter than an additional bolt, washers, and nut. One screw would have been sufficient. I'm finding the screws loosen with time and I've had to go to a larger size screw to make them tight. I found another one just last week when I had the cowl off. I just don't want my speed brake to come loose and start flapping in the breeze. :-) Larry Flesner
