Airworthiness Directive · Amendment 39-13984 · Saab Model SAAB SF340A and SAAB 340B Series Airplanes
Saab Model SAAB SF340A and SAAB 340B Series Airplanes
Superseded. A later AD replaced this one: AD 2007-02-16. Comply with the one in force.
This AD applies to Saab Model SAAB SF340A series airplanes having serial numbers 004 through 159 inclusive, and Model SAAB 340B series airplanes having serial numbers 160 through 367 inclusive; certificated in any category; on which Saab Service Bulletin 340-24-026 (Modification 2533) has not been implemented.
The FAA is adopting a new airworthiness directive (AD) for certain Saab Model SAAB SF340A and SAAB 340B series airplanes. This AD requires repetitive inspections for wear of the brushes and leads and for loose rivets of the direct current (DC) starter generator, and related investigative/corrective actions if necessary. This AD is prompted by reports of premature failures of the DC starter generator prior to scheduled overhaul. We are issuing this AD to prevent failure of the starter generator, which could cause a low voltage situation in flight and result in increased pilot workload and reduced redundancy of the electrical powered systems.
You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.
For generators overhauled in accordance with Maintenance Review Board (MRB) Task 243104: Before 800 flight hours since the last overhaul or within 100 flight hours after the effective date of this AD, whichever occurs later, perform a general visual inspection for wear of the DC starter generator brushes and leads, in accordance with Saab Service Bulletin 340-24-035, dated July 5, 2004.
Note 1: For the purposes of this AD, a general visual inspection is “a visual examination of a 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 normal available lighting conditions such as daylight, hangar lighting, flashlight or drop-light 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.”
Note 2: Saab Service Bulletin 340-24-035, dated July 5, 2004, references Goodrich Service Information Letter 23080-03X-24-01, dated July 1, 2004, as an additional source of service information.
(1) If the tops of the brush sets are above the top of the brush box, repeat the inspection at intervals not to exceed 800 flight hours.
(2) If the tops of the brush sets are below the top of the brush box, before further flight, measure the brushes and determine the remaining amount of brush life remaining, in accordance with the service bulletin.
(i) If the brush wear is within the limits specified in the service bulletin, repeat the inspection at intervals not to exceed 800 flight hours.
(ii) If the brush wear is outside the limits specified in the service bulletin, before further flight, replace the starter generator with a new or serviceable starter generator, in accordance with the service bulletin.
For generators overhauled in accordance with MRB Task 243104: Before 800 flight hours since last overhaul or within 100 flight hours after the effective date of this AD, whichever occurs later, perform a general visual inspection of each leading wafer brush for loose rivets, in accordance with Saab Service Bulletin 340-24-035, dated July 5, 2004. Repeat the inspections at intervals not to exceed 800 flight hours. If any rivet is loose, before further flight, replace the DC starter generator with a new or serviceable starter generator, in accordance with the service bulletin.
For generators overhauled or with brush replacement accomplished in accordance with MRB Task 243103 or 243101, no action is required by 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
