CS 25.685 Control system details

In assessing compliance with CS 25.685(a) account should be taken of the jamming of control circuits by the accumulation of water in or on any part which is likely to freeze. Particular attention should be paid to the following: a. The points where controls emerge from pressurised compartments. b. Components in parts of the aeroplane which could be contaminated by the water systems of the aeroplane in normal or fault conditions; if necessary such components should be shielded. c. Components in parts of the aeroplane where rain and/or condensed water vapour can drip or accumulate. d. Components inside which water vapour can condense and water can accumulate.