Airworthiness Directive · Amendment 39-21006 · Wings
The Boeing Company Airplanes
This AD applies to all The Boeing Company Model MD-90-30 airplanes, certificated in any category.
The FAA is adopting a new airworthiness directive (AD) for all The Boeing Company Model MD-90-30 airplanes. This AD was prompted by reports indicating that certain center wing stringers and skins are potentially susceptible to cracking. This AD requires repetitive eddy current, low frequency (ETLF) inspections of the left and right side fastener holes for any crack; repetitive eddy current, high frequency (ETHF) inspections of the lower skin for any crack; and repair if any crack is found. The FAA is issuing this AD to address the unsafe condition on these products.
Except as specified in paragraph (h) of this AD: At the applicable times specified in paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin MD90-57A031, dated March 19, 2019, do all applicable actions identified as “RC” (required for compliance) in, and in accordance with, the Accomplishment Instructions of Boeing Alert Service Bulletin MD90-57A031, dated March 19, 2019.
Note 1 to paragraph (g) of this AD: Boeing Alert Service Bulletin MD90-57A031, dated March 19, 2019, refers to Boeing Drawing SN09570007, as data supplied with this service bulletin. If the pages of Boeing Drawing SN09570007 are illegible, guidance can be found in Boeing Multi Operator Message MOM-MOM-19-0549-01B, dated October 4, 2019.
(1) For purposes of determining compliance with the requirements of this AD: Where Boeing Alert Service Bulletin MD90-57A031, dated March 19, 2019, uses the phrase “the original issue date of this service bulletin,” this AD requires using “the effective date of this AD.”
(2) Where Boeing Alert Service Bulletin MD90-57A031, dated March 19, 2019, specifies contacting Boeing for repair instructions and doing the repair: This AD requires doing the repair using a method approved in accordance with the procedures specified in paragraph (i) of this AD.
