AD FAA-2019-0859

The FAA is adopting a new airworthiness directive (AD) for certain The Boeing Company Model 747-100, 747-100B, 747-100B SUD, 747- 200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F, 747SR, and 747SP series airplanes. This AD was prompted by fuel system reviews conducted by the manufacturer indicating that the existing bond path design provides insufficient bond resistance margin between the fuel pump motor/impeller and structure. This AD requires replacement of the bonding jumpers on the auxiliary power unit (APU) fuel pump. This AD also requires, for certain airplanes, installation of a second bonding jumper; an inspection of the override/jettison fuel pumps and transfer/ jettison fuel pumps to determine if the bonding jumper has a one-piece braid or two-piece braid and replacement of the bonding jumper if necessary; and replacement of the bonding jumper on the electrical scavenge fuel pump. The FAA is issuing this AD to address the unsafe condition on these products.