Airworthiness Directive · Amendment 39-18283 · Wings
Lockheed Martin Corporation/Lockheed Martin Aeronautics Company Airplanes
This AD applies to Lockheed Martin Corporation/Lockheed Martin Aeronautics Company Model 188A and 188C airplanes, certificated in any category, serial numbers 1001 and subsequent.
We are adopting a new airworthiness directive (AD) for certain Lockheed Martin Corporation/Lockheed Martin Aeronautics Company Model 188 series airplanes. This AD was prompted by an evaluation by the design approval holder (DAH) indicating that the upper and lower wing skin planks at the attachment of the main landing gear (MLG) ribs at certain wing-stations are subject to widespread fatigue damage (WFD). This AD requires an inspection (for cracking) and modification of the chordwise fastener rows of the upper and lower wing planks at the attachments to the MLG ribs at certain wing-stations. We are issuing this AD to prevent fatigue cracking of the upper and lower wing skin planks at the attachment of the MLG ribs, which could result in failure of the wing.
At the later of the times specified in paragraphs (g)(1) and (g)(2) of this AD: Remove the chordwise fastener rows of the upper and lower wing planks at the attachments to the MLG ribs at wing-station (WS) 167 and WS 209; do a bolt-hole eddy current (BHEC) inspection to detect cracking of the fastener rows; and replace the original fasteners with new, first oversize fasteners; in accordance with the Accomplishment Instructions of Lockheed Martin Electra Service Bulletin 88/SB-721, dated April 30, 2014. If any cracking is found during any inspection required by this paragraph: Before further flight, repair the cracking, in accordance with the Accomplishment Instructions of Lockheed Martin Electra Service Bulletin 88/SB-721, dated April 30, 2014.
(1) At the applicable time specified table 1 of paragraph 1.E., “Compliance,” of Lockheed Martin Electra Service Bulletin 88/SB-721, dated April 30, 2014. Where table 1 of paragraph 1.E., “Compliance,” of Lockheed Martin Electra Service Bulletin 88/SB-721, dated April 30, 2014, specifies “Flt. Hrs,” this AD specifies “total flight hours.”
(2) Within 365 days or 600 flight hours after the effective date of this AD, whichever occurs first.
Although Lockheed Martin Electra Service Bulletin 88/SB-721, dated April 30, 2014, specifies to submit certain information to the manufacturer, this AD does not include that requirement.
