Regulations allow pilots to perform many simple maintenance actitivies, generally determined by the airplane manufacturer and listed in the aircraft's Maintenance Manual. All other operations require a A&P or IA to be involved.
Pilots can work on their own plane, but only under the close supervision of a cooperative A&P or IA. If you can convince the A&P that you are competent, many will cheerfully participate in pilot performed work under their supervision. I always worked on my own race cars, I am "fussy" about doing things right, and working on my own plane was important to me. The main advantage is not cost savings. The main advantage is the pilot's familiarity with and confidence in, his aircraft.
My first experience with this was the replacement of the tail wheel springs on Sierra Charlie.
Over time, the leaf spring loses it's arch and sags---this reduces the "caster" and the "trailing distance" of the wheel.
My CFI, Joe insisted that the condition of my leaf spring and the use of "compression" steering springs was not ideal and would limit my ability to control the plane in crosswinds. So, I called CubCrafters for "factory" advice and was told to replace the leaf spring and the steering springs with factory approved parts. (extension type steering springs) Essentially the factory expert was in complete agreement with Joe.
Once I had the parts, I carefully organized the parts/hardware and tools at the repair site and had the A&P perform the initial inspection and review. We discussed how I would make the repairs and he asked me to bring the old spring to his shop so we could compare the weights. I installed the new leaf spring and steering springs, and the A&P carefully inspected my work, signing off in the airplane's log book.
Here are pics of before and after.
Seems to be a lot of controversy about steering springs and their "ideal" set up. The "compression" type allow a secure assembly that is unlikely to come apart during flight. The "extension" springs have a small opening in the "hook" section that theoretically could allow them to be unhooked during flight when slack. The "compression" type spring becomes solid when loaded beyond a certain point--hence generally the set up calls for a bit of slack which creates a "null zone" where the rudder does not move the tail wheel. (It is often argued that this "solid" position can lead to steering arm damage.) The "extension" spring does not "become solid" and generally is set up with less slack and therefore less "null zone". This "null zone" not only affects how much rudder movement without tail wheel movement---it also determines how much the tail wheel is moved at full rudder extension in high cross winds.
My solution to the risk of the extension springs becoming unhooked when slack, after discussions with the A&P was using rubber "safety end caps" that I constructed using short sections of fabric reinforced rubber hose and silicone sealant/adhesive slid over the hook tip, filling the gap.
Replacing the sagging leaf spring restores the factory designed "three point attitude" and reduces the angle of attack.
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