I recently found myself with a few hours to kill while in the Dallas, Texas area. On the advice of a Tested reader, I made my way to the Cavanaugh Flight Museum, and I'm glad I did. Cavanaugh is my favorite kind of aviation museum to visit. It has a very eclectic mix of static and airworthy aircraft that spans from WWI to the modern era. Several of the airplanes in the museum's collection are combat veterans as well.
Of all the various aircraft vying for my attention, the one that I spent the most time with was a humble-looking former navy machine, the Grumman S-2F Tracker. While I had seen various versions of the cold-war-era S-2 at airshows, this was the first opportunity I'd had to get a good up-close look at its wing folding mechanism.
The S-2F was parked outdoors with its wings folded as if it were on an aircraft carrier. I spent several minutes analyzing the various parts that were visible at the wing folds while trying to figure out the purpose of each. The functions of some components seemed obvious, but most remained a mystery. I walked away utterly fascinated by the intricacies of folding wings and determined to learn more.
It's All About Elbow Room
The concept of folding wings is nearly as old as aviation itself. Irish airplane company, Short Brothers, developed a series of biplanes with folding wings prior to the start of WWI. The idea has persevered with most modern naval aircraft, and even the Boeing 777X passenger jet. The goal of folding wings in every instance is to give the airplane a smaller storage footprint when not in use.
Wide-spread implementation of folding wings came about during WWII with the emergence of the aircraft carrier as the prime offensive naval weapon. Folding wings allowed up to 50% more aircraft to be stored aboard these ships. By the end of the war, folding wings were standard equipment on nearly every carrier-based aircraft. There have been very few exceptions in the decades since.