Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain McDonnell Douglas MD-90-30 series airplanes. This proposal would require inspection of the power feeder cables on the left and right side of the aft cargo compartment between certain stations for minimum clearance from the adjacent structure and for the presence of a grommet in the lightening hole through the floor cusp, and corrective actions, if necessary. This action is necessary to detect and correct inadequate clearance of the power feeder cables on the left and right side of the aft cargo compartment, the lack of a grommet in the lightening hole through the floor cusp, and improper installation of the cabin sidewall grill during production. These conditions could lead to chafing of the power feeder cables, resulting in electrical arcing and possibly in a fire in the cargo compartment of the airplane. This action is intended to address the identified unsafe condition.