airworthiness · Rule · Final rule. · Published 2013-09-04 · Effective 2013-10-09 · 78 FR 54377
Document
Document number
2013-21071
Federal Register citation
78 FR 54377
Type
Rule
Action
Final rule.
Category
airworthiness
Manufacturer
Airbus
Publication date
2013-09-04
Effective date
2013-10-09
FAA docket
Docket No. FAA-2013-0094
Abstract
We are adopting a new airworthiness directive (AD) for all Airbus Model A318, A319, A320, and A321 series airplanes. This AD was prompted by reports that certain trimmable horizontal stabilizer actuators (THSA) were found with corrosion that affected the ballscrew lower splines between the tie-bar and screw-jack. This AD requires repetitive inspections of the THSA; ballscrew integrity tests, if necessary; and replacement of affected THSAs. We are issuing this AD to detect and correct corrosion in the ballscrew lower splines, which, if the ballscrew ruptured, could lead to transmission of THSA torque loads from the ballscrew to the tie-bar, prompting THSA blowback, and possible loss of control of the airplane.