Summary
We propose to supersede Airworthiness Directive (AD) 2013-02- 12, which applies to all EADS CASA (now Airbus Defense and Space S.A.) Model CN-235, CN-235-100, CN-235-200, and CN-235-300 airplanes. AD 2013-02-12 currently requires a one-time inspection to identify the correct polarity for each pair of electrical connectors on each engine fire extinguisher cartridge, and repair if necessary. Since we issued AD 2013-02-12, we have determined it is necessary to add a requirement for modifying the installation of the fire extinguisher circuit harness. This proposed AD would continue to require identifying the correct polarity of each pair of electrical connectors of the affected engine fire extinguisher cartridge, and doing a repair if necessary. This proposed AD would also require modifying the installation of the fire extinguisher circuit harnesses. We are proposing this AD to address the unsafe condition on these products.