Summary
The FAA proposes to adopt a new airworthiness directive (AD) for certain EMBRAER Model EMB-135 airplanes, and Model EMB-145, -145ER, -145MR, -145LR, -145XR, -145MP, and -145EP airplanes. This proposed AD would require modification of the upper frame of the firewall for the auxiliary power unit (APU). This proposed AD results from the discovery of a hole in the upper frame of the firewall for the APU. We are proposing this AD to prevent smoke from entering the passenger cabin in the event of a fire in the APU compartment.