Airworthiness Directive · Amendment 39-18216 · Hydraulic power
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) 2015-10-01 for certain Bombardier, Inc. Model DHC-8-400 series airplanes. AD 2015-10- 01 required inspection for correct assembly of the main landing gear (MLG) alternate extension system reservoir lid, and corrective action if necessary. This new AD revises the applicability. This AD was prompted by the discovery of two errors in the applicability of AD 2015-10-01. We are issuing this AD to, in the event of a failure of the primary MLG extension system, prevent failure of the alternate MLG extension system to fully extend the MLG into a down-and-locked position, which could result in collapse of both left-hand and right- hand MLG sides during touchdown.
This paragraph restates the requirements of AD 2015-10-01, Amendment 39-18156 (80 FR 32449, June 9, 2015), with no changes. Within 2,000 flight hours or 12 months after July 14, 2015 (the effective date of AD 2015-10-01), whichever occurs first: Do a general visual inspection of the MLG alternate extension system reservoir lid for correct assembly, and do all applicable corrective actions, in accordance with the Accomplishment Instructions of Bombardier Service Bulletin 84-29-34, dated May 9, 2013, and with the attached Parker Service Bulletin 82910012-29-431, dated October 22, 2012, as referenced in Bombardier Service Bulletin 84-29-34, dated May 9, 2013. Do all applicable corrective actions within 2,000 flight hours or 12 months after July 14, 2015, whichever occurs first.
This paragraph restates the provisions of paragraph (h) of AD 2015-10-01, Amendment 39-18156 (80 FR 32449, June 9, 2015), with no changes. This paragraph provides credit for actions required by paragraph (g) of this AD, if those actions were performed before July 14, 2015 (the effective date of AD 2015-10-01), using Bombardier All Operator Message 543, dated October 17, 2012, which is not incorporated by reference in this AD.
