One of the early pioneers of helicopter flying was Carl Brady. In early 1947 he was crop dusting in a Stearman airplane when he saw a Bell 47B-3 spraying a field. Intrigued, he approached the owner and worked a deal out to get his helicopter pilot license. That same year he and two partners leased a couple of Bell 47B-3 helicopters and started their own operation.
Early helicopters, including the Bell 47B-3, used wheels for landing gear – probably a design borrowed from airplanes. Brady discovered that this was a bad idea for helicopters. He was known to tell a story that many consider the birth of skid type landing gear. It was 1948 and he and a former Bell mechanic were flying for the first time in Alaska. They discovered that the wheels would caster on rocky mountain tops or slopes causing the helicopter to roll downhill. To solve this problem they had a local sawmill cut two two-by-fours out of hardwood and using clothes line tied them to each wheel. It kept the wheels from castering and made landing on soft terrain much easier. Because there was no STC, they would fly their missions during the day and then remove the two-by-fours and fly back to town.
I have never read anything regarding the former Bell mechanic’s comments on the Alaskan adventure; however, two years later Bell introduced the Model 47D-1 with metal tube skid gear instead of wheels. This design became the standard for light helicopters for decades.