Summary
The FAA proposes to adopt a new airworthiness directive (AD) for certain EMBRAER airplanes listed above. This proposed AD would require modifying the drain system of the auxiliary power unit (APU) by installing a scavenge pump and, for certain airplanes, replacing the APU exhaust assembly. This proposed AD results from a report of fuel leaking from the APU feeding line and accumulating inside the APU compartment because the drain system is inadequate when the APU is running. We are proposing this AD to prevent fuel accumulation and subsequent flammable fuel vapors in the APU cowling, which, combined with an ignition source, could result in a fire or explosion.