Airworthiness Directive · Amendment 39-17550 · Nacelles/pylons
Bombardier, Inc. Airplanes
This AD applies to Bombardier, Inc. Model DHC-8-102, -103 airplanes, and airplanes converted to Model DHC-8-106 in accordance with Bombardier Service Bulletin 8-92-07 or Bombardier Service Bulletin 8-92-08, serial numbers 003 through 287 inclusive, with pre-modification 8/1593 nacelle lower longeron installed; certificated in any category.
We are adopting a new airworthiness directive (AD) for certain Bombardier, Inc. Model DHC-8-102, -103, and -106 airplanes. This AD was prompted by a report of cracking in a lower longeron in a nacelle. This AD requires repetitive inspections for cracking of the lower longerons in the nacelles, and replacement with new longerons or repair if necessary. Additionally, this AD specifies an optional terminating action. We are issuing this AD to detect and correct such cracking, which could result in degradation of the structural integrity of the nacelle and possible collapse of the main landing gear (MLG).
You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.
At the applicable time specified in paragraph (g)(1), (g)(2), (g)(3), or (g)(4) of this AD: Do a detailed visual inspection or a bolt-hole eddy current (BHEC) test for cracking of each nacelle lower longeron, in accordance with the Accomplishment Instructions of Bombardier Service Bulletin 8-54-39, Revision B, dated March 13, 2013.
(1) For Model DHC-8-102 and -103 airplanes that have accumulated 35,000 total flight cycles or less as of the effective date of this AD: Within 5,000 flight cycles after the effective date of this AD, but not to exceed 36,000 total flight cycles.
(2) For Model DHC-8-102 and -103 airplanes that have accumulated more than 35,000 total flight cycles as of the effective date of this AD: Within 1,000 flight cycles after the effective date of this AD.
(3) For Model DHC-8-106 airplanes with the Pre-Modification 8/1641 configuration, within 500 flight cycles after the effective date of this AD.
(4) For Model DHC-8-106 airplanes with the Post-Modification 8/1641 configuration, within 5,000 flight cycles after the effective date of this AD.
After accomplishment of the actions required by paragraph (g) of this AD, at the applicable time specified in paragraph (h)(1) or (h)(2) of this AD: Do repetitive BHEC testing for cracking of each nacelle lower longeron, in accordance with the Accomplishment Instructions of Bombardier Service Bulletin 8-54-39, Revision B, dated March 13, 2013, until the terminating action specified in paragraph (j) of this AD is done.
(1) For Model DHC-8-102 and -103 airplanes, at intervals not to exceed 2,500 flight cycles.
(2) For Model DHC-8-106 airplanes, at intervals not to exceed 1,854 flight cycles.
If any cracking is found during any inspection required by paragraph (g) or (h) of this AD: Before further flight, replace any cracked nacelle lower longeron with a new longeron, in accordance with the Accomplishment Instructions of Bombardier Service Bulletin 8-54-39, Revision B, dated March 13, 2013; or repair the longeron using a method approved by either the Manager, New York ACO, ANE-170, FAA, or Transport Canada Civil Aviation (TCCA) (or its delegated agent).
Accomplishment of the actions specified in paragraphs (j)(1) and (j)(2) of this AD constitutes terminating action for the repetitive BHEC testing specified in paragraph (h) of this AD for that longeron only.
(1) Replacement of the nacelle lower longeron, in accordance with the Accomplishment Instructions of Bombardier Service Bulletin 8-54-39, Revision B, dated March 13, 2013.
(2) Cold working of the drain holes, in accordance with the Accomplishment Instructions of Bombardier Service Bulletin 8-54-39, Revision B, dated March 13, 2013.
