Airworthiness Directive · Amendment 39-18822 · Landing gear
Bombardier, Inc. Airplanes
This AD applies to Bombardier, Inc. Model DHC-8-400, -401, and -402 airplanes, certificated in any category, serial numbers 4001 through 4424 inclusive.
We are superseding Airworthiness Directive (AD) 2012-08-11 for certain Bombardier, Inc. Model DHC-8-400 series airplanes. AD 2012-08- 11 required repetitive inspections for defects and damage of the retract port flexible hoses on the main landing gear (MLG) retraction actuators, and replacement if necessary. This AD continues to require the actions in AD 2012-08-11, requires reorientation of the retraction actuator of the MLG, and removes airplanes from the applicability. This AD was prompted by test results that showed that failure of a retract port flexible hose of a MLG retraction actuator could cause excessive hydraulic fluid leakage. We are issuing this AD to address the unsafe condition on these products.
This paragraph restates the requirements of paragraph (g) of AD 2012-08-11, with new reference to terminating action. Within 600 flight hours after May 29, 2012 (the effective date of AD 2012-08-11), do a detailed inspection for defects and damage of the retract port flexible hose of the left and right MLG retraction actuators, in accordance with the Accomplishment Instructions of Bombardier Service Bulletin 84-32-89, dated March 22, 2011. Repeat the inspection thereafter at intervals not to exceed 600 flight hours. If any defect or damage is found, before further flight, replace the retract port flexible hose with a new or serviceable retract port flexible hose, in accordance with the Accomplishment Instructions of Bombardier Service Bulletin 84-32-89, dated March 22, 2011. Doing the actions required by paragraph (h) of this AD terminates the inspections required by this paragraph.
Within 6,000 flight hours or 36 months, whichever occurs first after the effective date of this AD: Reorient the MLG retraction actuator by incorporating Bombardier Modification Summaries 4-902418 and 4-902327, in accordance with the Accomplishment Instructions of the applicable service information specified in paragraphs (h)(1) and (h)(2) of this AD. Accomplishment of the actions required by this paragraph terminates the actions required by paragraph (g) of this AD.
(1) Bombardier Service Bulletin 84-32-105, Revision A, dated April 24, 2015; and Goodrich Service Bulletin 46550-32-99 R2, dated February 19, 2015.
(2) Bombardier Service Bulletin 84-32-106, Revision B, dated June 18, 2015; and Goodrich Service Bulletin 46455-32-100 R1, dated March 20, 2013.
