Airworthiness Directive · Amendment 39-19235 · Ice and rain protection
the Boeing Company Airplanes
This AD applies to all The Boeing Company Model DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 (MD-83), and DC-9-87 (MD-87) airplanes, Model MD-88 airplanes, and Model MD-90-30 airplanes, certificated in any category.
We are adopting a new airworthiness directive (AD) for all The Boeing Company Model DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 (MD-83), and DC-9-87 (MD-87) airplanes, Model MD-88 airplanes, and Model MD-90- 30 airplanes. This AD was prompted by a report of loss of airspeed indication due to icing. This AD requires modifying the air data heat (ADH) system. We are issuing this AD to address the unsafe condition on these products.
At the applicable time specified in paragraph (g)(1) or (g)(2) of this AD: Do all applicable actions identified as “RC” (required for compliance) in, and in accordance with, the Accomplishment Instructions of Boeing Alert Service Bulletin MD80-30A132, dated April 28, 2017; or Boeing Alert Service Bulletin MD90-30A031, dated June 2, 2017; as applicable; except as required by paragraph (h) of this AD.
(1) For Model DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 (MD-83), DC-9-87 (MD-87), and Model MD-88 airplanes: Within 28 months after the effective date of this AD.
(2) For Model MD-90-30 airplanes: Within 27 months after the effective date of this AD.
Where Boeing Alert Service Bulletin MD80-30A132, dated April 28, 2017, specifies contacting Boeing, and specifies that action as “RC” (Required for Compliance): This AD requires using a method approved in accordance with the procedures specified in paragraph (j) of this AD.
In the event that the ADH system as modified by this AD is inoperable, an airplane may be operated as specified in the operator's MEL, provided provisions that address the modified ADH system are included in the MEL.
