An additional section that must be checked during an annual inspection on a complex aircraft is the landing gear!
During this inspection, we started with the gear swing to verify full operation of the extension and retraction cycle as well as an emergency gear drop. I climbed up into the cockpit after jacking up the Arrow to operate the gear... I like to think I got some free flight time while performing the check while being suspended of the ground ;)
After the gear swing, it was time to get down on all fours for close up examination. This includes wiggling the gear to make sure there’s not a whole lot of play, checking linkages and bushings as well as greasing the bolts and spraying linkages with corrosion resistant for preservation purposes.
Cleaning the gear struts with hydraulic fluid does the job better than other cleaners or degreasers in my opinion. Besides, you don't have to worry about chemicals getting trapped in unwanted areas as the gear moves.
In this picture (left) you can see the little micro switch for the right main that is responsible for detecting the position of the landing gear as well as the one for the nose gear (right). When the gear is up, the switch is opened and when the wheel is extended, the switch is closed, making a connection that tells the aircraft the gear is down. Each switch is wired to an indicator light in the cockpit to show the wheel positions. There ya go, it's mechanical magic!
I hope you love learning how aircraft operate as much as I do and remember: "In being a mechanic, you become a better pilot and in being a pilot, you become a better mechanic!"
- LIV2FLY