Airworthiness Directive · Amendment 39-11792 · Saab Model SAAB SF340A and SAAB 340B Series Airplanes
Saab Model SAAB SF340A and SAAB 340B Series Airplanes
Model SAAB SF340A, serial numbers -004 through -159 inclusive; and SAAB 340B series airplanes, serial numbers -160 through -459 inclusive; certificated in any category.
Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (c) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.
This amendment adopts a new airworthiness directive (AD), applicable to certain Saab Model SAAB SF340A and SAAB 340B series airplanes, that requires a one-time inspection to detect chafing of the wires and harnesses in the cabin compartment ceiling; repair, if necessary; and installation of protective sleeving. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to prevent false warnings of a hot engine exhaust tailpipe and intermittent signal failure, which could result in the consequent execution of unnecessary procedures by the flightcrew.
To prevent false warning of a hot engine exhaust tailpipe and intermittent signal failure, the consequent execution of unnecessary procedures by the flightcrew, accomplish the following:
(a) Prior to the accumulation of 14,000 total flight hours, or within 4,000 flight hours after the effective date of this AD, whichever occurs later: Perform a detailed visual inspection to detect chafing of the wires and harnesses in the cabin compartment ceiling, and install protective sleeving on all of the harnesses routed in the inspection area; in accordance with Saab Service Bulletin 340-92-027, dated December 10, 1999. Except as provided by paragraph (b) of this AD, prior to further flight, repair any chafing in accordance with the service bulletin.
Note 2: For the purposes of this AD, a detailed visual inspection is defined as: “An intensive visual examination of a specific structural area, system, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at intensity deemed appropriate by the inspector. Inspection aids such as mirror, magnifying lenses, etc., may be used. Surface cleaning and elaborate access procedures may be required.”
(b) For any chafing detected during the inspection required by paragraph (a) of this AD for which the service bulletin specifies to contact Saab for appropriate action: Prior to further flight, repair in accordance with a method approved by the Manager, International Branch, ANM-116, FAA, Transport Airplane Directorate; or the Luftfartsverket (LFV) (or its delegated agent). For a repair method to be approved by the Manager, International Branch, ANM-116, as required by this paragraph, the Manager's approval letter must specifically reference this AD.
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
