14 CFR · Part 25
14 CFR § 25.1703
Function and installation: EWIS.
Each EWIS component installed in any area of the aircraft must:
Be of a kind and design appropriate to its intended function.
Be installed according to limitations specified for the EWIS components.
Perform the function for which it was intended without degrading the airworthiness of the airplane.
Be designed and installed in a way that will minimize mechanical strain.
Selection of wires must take into account known characteristics of the wire in relation to each installation and application to minimize the risk of wire damage, including any arc tracking phenomena.
The design and installation of the main power cables (including generator cables) in the fuselage must allow for a reasonable degree of deformation and stretching without failure.
EWIS components located in areas of known moisture accumulation must be protected to minimize any hazardous effects due to moisture.
Reflects the eCFR edition current as of September 29, 2026. Retrieved from ecfr.gov on October 16, 2026.
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