Airworthiness Directive · Amendment 39-21691 · Fuselage
The Boeing Company Airplanes
This AD applies to The Boeing Company Model 737-800 and -900ER series airplanes, certificated in any category, with ViaSat In-Flight Connectivity (IFC) System Antenna Provisions installed in accordance with Astronics Armstrong Aerospace Supplemental Type Certificate (STC) ST04096CH.
The FAA is adopting a new airworthiness directive (AD) for certain The Boeing Company Model 737-800 and -900ER series airplanes. This AD was prompted by reports that several of the fittings that provide attachment between the radome and fuselage were cracked to the point of failure on airplanes modified in accordance with a certain supplemental type certificate (STC). This AD requires demodification of the STC installation on the airplane by removing the external equipment installed during the STC modification (including the radome, antenna, and associated structure), installing doubler and fasteners, and system deactivation by pulling and collaring associated circuit breakers if installed. This AD also requires inspecting the external and feed- through doublers, intercostals, skin, and frames in the area around the removed external equipment for cracking, and repair if necessary. The FAA is issuing this AD to address the unsafe condition on these products.
Before further flight, remove external equipment (including radome, antenna, and associated structure) that was installed in accordance with STC ST04096CH. Do the removal in accordance with steps 1 through 9 of paragraph 5.2.1., of Astronics Armstrong Aerospace Engineering Order, “ViaSat In-Flight Connectivity (IFC) System DE-MOD Boeing 737-800/-900ER Series Aircraft,” Document No. EO23-9642-02, Revision B, dated April 25, 2016.
Before further flight after accomplishing the removal required by paragraph (g) of this AD, inspect the external and feed-through doublers, intercostals, skin, stringers, and frames in the area around the removed external equipment for any cracking in accordance with paragraph 3.3., “Inspection,” of Astronics Connectivity Systems and Certification Service Bulletin SB44-9642-01, dated July 8, 2021. If any cracking is found, before further flight, repair using a method approved in accordance with the procedures specified in paragraph (j) of this AD.
Before further flight after accomplishing the actions required by paragraph (h) of this AD: Install doubler and fasteners and deactivate the system (including pulling and collaring associated circuit breakers if installed) in accordance with steps 10, 11, and 12 of paragraph 5.2.1., of Astronics Armstrong Aerospace Engineering Order, “ViaSat In-Flight Connectivity (IFC) System DE-MOD Boeing 737-800/-900ER Series Aircraft,” Document No. EO23-9642-02, Revision B, dated April 25, 2016.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
Aircraft
