Mooney M20 Control Wheel Shaft Fatigue Cracks  Notice Number: NOTC3947   The FAA is investigating the report of a control wheel separation on a Mooney M20C aircraft due to fatigue cracks in the control shaft or control wheel attachment hub. This failure might result in momentary loss of control of the aircraft until the pilot or copilot is able to regain control with the second control wheel. This may reduce the capability of the airplane or the ability of the crew to cope with adver