Summary
We are revising an earlier proposed airworthiness directive (AD) for certain The Boeing Company Model 757-200, -200PF, -200CB, and -300 series airplanes. The NPRM proposed to require, for certain airplanes, installing new relays adjacent to two of the spoiler control modules. For certain other airplanes, the NPRM proposed to require torquing the bracket assembly installation nuts and ground stud nuts, and doing bond resistance tests between the bracket assemblies and the terminal lugs on the ground studs. The NPRM was prompted by numerous reports of unintended lateral oscillations during final approach, just before landing. This action revises the NPRM by adding actions that are necessary to address the identified unsafe condition. We are proposing this supplemental NPRM (SNPRM) to reduce the chance of unintended lateral oscillations near touchdown, which could result in loss of lateral control of the airplane, and consequent airplane damage or injury to flight crew and passengers. Since these actions impose an additional burden over that proposed in the NPRM, we are reopening the comment period to allow the public the chance to comment on these proposed changes.