Airworthiness Directive · Amendment 39-16664 · Fuselage
Saab AB, Saab Aerosystems Model 340A (SAAB/SF340A) and SAAB 340B Airplanes Modified in Accordance With Supplemental Type Certificate (STC) ST00224WI-D, ST00146WI-D, or SA984GL-D
This AD applies to Saab AB, Saab Aerosystems airplanes, certificated in any category, identified in paragraphs (c)(1) and (c)(2) of this AD, that have been modified in accordance with Supplemental Type Certificate (STC) ST00224WI-D, ST00146WI-D, or SA984GL-D.
(1) Model 340A (SAAB/SF340A) airplanes, serial numbers 004 through 159 inclusive.
(2) Model SAAB 340B airplanes, serial numbers 160 through 459 inclusive.
We are adopting a new airworthiness directive (AD) for the products listed above. This AD requires inspecting the fuselage surface for corrosion and cracking behind the external adapter plate of the antennae installation, and repair if necessary. This AD was prompted by a report of a crack found behind the external adapter plate of the antennae during inspection. Similar cracking was found on two additional airplanes, and extensive corrosion was found on one airplane. We are issuing this AD to detect and correct corrosion and cracking behind the external adapter plate of the antennae of certain damage-tolerant structure, which could result in reduced structural integrity and consequent rapid depressurization of the airplane.
You are responsible for having the actions required by this AD performed within the compliance times specified.
Within 600 flight cycles after the effective date of this AD: Remove the external adapter plate of the antennae installation and do a general visual inspection of the fuselage surface for corrosion and cracking behind the external adapter plate of the antennae installation. If any corrosion or cracking is found, repair before further flight. If no corrosion or cracking is found, before further flight, ensure that proper corrosion protection has been applied before reinstalling the adapter plate. Do all the actions required by this paragraph in accordance with a method approved by the Manager, Wichita Aircraft Certification Office (ACO), FAA.
Note 1: For the purposes of this AD, a general visual inspection is: “A visual examination of an interior or exterior area, installation, or assembly to detect obvious damage, failure, or irregularity. This level of inspection is made from within touching distance unless otherwise specified. A mirror may be necessary to ensure visual access to all surfaces in the inspection area. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight, or droplight and may require removal or opening of access panels or doors. Stands, ladders, or platforms may be required to gain proximity to the area being checked.”
At the applicable time specified in paragraph (h)(1) or (h)(2) of this AD: Submit a report of the positive findings of the inspections required by paragraph (g) of this AD. Send the report to the Manager, Wichita ACO. The report must contain, at a minimum, the inspection results, a description of any discrepancies found, the airplane serial number, and the number of flight cycles and flight hours on the airplane since installation of the STC.
(1) If the inspection was done on or after the effective date of this AD: Submit the report within 30 days after the inspection.
(2) If the inspection was done before the effective date of this AD: Submit the report within 30 days after the effective date of this AD.
(3) A federal agency may not conduct or sponsor, and a person is not required to respond to, nor shall a person be subject to a penalty for failure to comply with a collection of information subject to the requirements of the Paperwork Reduction Act unless that collection of information displays a current valid OMB Control Number. The OMB Control Number for this information collection is 2120-0056. Public reporting for this collection of information is estimated to be approximately 5 minutes per response, including the time for reviewing instructions, completing and reviewing the collection of information. All responses to this collection of information are mandatory. Comments concerning the accuracy of this burden and suggestions for reducing the burden should be directed to the FAA at: 800 Independence Ave., SW., Washington, DC 20591, Attn: Information Collection Clearance Officer, AES-200.
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
