Airworthiness Directive · Amendment 39-15947 · Stabilizers
McDonnell Douglas Model MD-90-30 Airplanes
This AD applies to all McDonnell Douglas Model MD-90-30 airplanes, certificated in any category.
We are adopting a new airworthiness directive (AD) for all McDonnell Douglas Model MD-90-30 airplanes. This AD requires repetitive inspections for cracks of the upper aft skin panels on the horizontal stabilizer, and related investigative and corrective actions if necessary. This AD results from a report of cracks found in the aft skin panels on the upper right side of the horizontal stabilizer at the aft inboard corner. We are issuing this AD to detect and correct cracks in the fail-safe structure that may not be able to sustain limit load, which could result in the loss of overall structural integrity of the horizontal stabilizer.
Comply with this AD within the compliance times specified, unless already done.
Except as required by paragraphs (h) and (i) of this AD: At the times specified in paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin MD90-55A012, dated September 23, 2008, do an eddy current inspection for cracks of the upper aft skin panels on the left and right sides of the horizontal stabilizer, and do all applicable related investigative and corrective actions, in accordance with the Accomplishment Instructions of the service bulletin.
Where Boeing Alert Service Bulletin MD90-55A012, dated September 23, 2008, specifies a compliance time after the date on the service bulletin, this AD requires compliance within the specified compliance time after the effective date of this AD.
(i) If any crack is found during any inspection required by this AD, and Boeing Alert Service Bulletin MD90-55A012, dated September 23, 2008, specifies to contact Boeing for appropriate action: Before further flight, repair using a method approved in accordance with the procedures specified in paragraph (k) of this AD.
Inspections and corrective actions done before the effective date of this AD are acceptable for compliance with the corresponding requirements of this AD, if done in accordance with Boeing Multiple Operator Message 1-669017091-1, dated November 9, 2007.
