I picked up a friend's C150 once, which had been sitting for months tied down, and lonely. After checking it over really well, jumping the battery, getting it running adequately, I took off to fly it home - entirely normal flight. When I was on short final, I pulled to raise the nose, and the elevator seemed jammed. With only a moment to spare as the ground rushed up, I pulled like hell, something released, and I could pull to flare, and landed okay. Very startled, I examined.
What had happened was that it sat all that time with the control lock through the control wheel tube. The constant motion (as it was parked down prevailing wind) had caused a burr on the control wheel tube around the control lock hole, which was just enough to catch in the plasitc bearing block on the instrument panel. It was enough to cause a jam. In takeoff and cruise, it was not a problem, as the control wheel was always well back. However the change in trim when the flaps are extended to 40, places the control lock hole just into the plastic bearing, and the jam is possible.
If on my preflight, I'd checked the "free" more cautiously with the "full", I might have noticed. But at the time, it had gone un noticed - and I learned....