AD FAA-2007-0250

The FAA is adopting a new airworthiness directive (AD) for certain Cirrus Design Corporation (Cirrus) Model SR22 airplanes. This AD requires you to install a drain hole in the left and right outboard wing tips. This AD results from reports of pilots' inability to move the aileron control without using excessive force when flying in freezing conditions. Moisture from a prior rain shower entered through a gap at the interface of the left and right outboard wing tips and wing structure. The moisture traveled along the aft wing shear web, accumulated below the aileron control pulley, and froze at an altitude with an outside air temperature below freezing. When this moisture is exposed to freezing conditions, operation of the aileron control pulley is impaired. We are issuing this AD to prevent moisture from accumulating along the wing shear web where it may freeze in certain conditions. This condition could result in operational failure of the aileron control pulley, which could lead to loss of control.