Airworthiness Directives; The Boeing Company Model 737-600, -700, -700C, -800, and -900 Series Airplanes

Resumo

We are revising an earlier proposed airworthiness directive (AD) for the products listed above. That NPRM proposed to require installation of an automatic shutoff system for the center tank fuel boost pumps, installation of a placard in the airplane flight deck if necessary, and concurrent modification of the P5-2 fuel control module assembly. That NPRM also proposed to require revisions to the Limitations and Normal Procedures sections of the airplane flight manual to advise the flightcrew of certain operating restrictions for airplanes equipped with an automated center tank fuel pump shutoff control. Additionally, that NPRM proposed to require a revision to the Airworthiness Limitations (AWL) section of the Instructions for Continued Airworthiness (ICA) to incorporate AWL No. 28-AWL-19 and No. 28-AWL-23. That NPRM further proposed to require installation of a secondary control relay for the electrical control circuit of each of the two center tank fuel boost pumps. That NPRM was prompted by fuel system reviews conducted by the manufacturer. This action revises that NPRM by adding airplanes, adding additional operational testing of the automatic shutoff system for certain airplane