Airworthiness Directive · Amendment 39-19371 · Ice and rain protection
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 4524 inclusive.
We are adopting a new airworthiness directive (AD) for certain Bombardier, Inc., Model DHC-8-400 series airplanes. This AD was prompted by reports of arcing and smoke emanating from the windshields. This AD requires a revision to the maintenance or inspection program, as applicable, to include an inspection of the windshield moisture seal for signs of cracks, erosion, wear, and other deterioration; doing that inspection and repair if necessary; and re-torqueing the screws that fasten the windshield heater terminal lugs and applying sealant to the screw heads of the windshield heaters. We are issuing this AD to address the unsafe condition on these products.
(1) Within 30 days after the effective date of this AD: Revise the maintenance or inspection program, as applicable, to incorporate the task specified in Bombardier Q400 Dash 8 Maintenance Review Board Report Temporary Revision (TR) MRB-0099, dated December 9, 2016.
(2) If the information in Bombardier Q400 Dash 8 Maintenance Review Board Report Temporary Revision (TR) MRB-0099, dated December 9, 2016, has been included in the general revisions of the Bombardier Q400 Dash 8 Maintenance Requirements Manual and the general revisions have been inserted into the maintenance or inspection program, as applicable, the requirement in paragraph (g)(1) of this AD is met.
After the maintenance or inspection program has been revised as required by paragraph (g) of this AD, no alternative actions (e.g., inspections) or intervals may be used unless the actions or intervals are approved as an alternative method of compliance (AMOC) in accordance with the procedures specified in paragraph (k)(1) of this AD.
Within 1,600 flight hours or 12 months after the effective date of this AD, whichever occurs first, do a general visual inspection of the moisture seal on the left and right windshields for signs of cracks, erosion, wear, and other deterioration (including discoloration, warping, or missing material). If any crack, erosion, wear, or other deterioration is found, before further flight, repair the moisture seal in accordance with a method approved by the Manager, New York ACO Branch, FAA; or Transport Canada Civil Aviation (TCCA); or Bombardier, Inc.'s TCCA Design Approval Organization (DAO). If approved by the DAO, the approval must include the DAO-authorized signature.
Note 1 to paragraph (i) of this AD: Additional guidance for inspection of the moisture seal can be found in Bombardier Q400 Dash 8 Maintenance Review Board (MRB) Task 561001E201, “General Visual Inspection of the Windshield Moisture Seal,” (Task 56-10-01-210-801, of the Bombardier Q400 Dash 8 Airplane Maintenance Manual).
Note 2 to paragraph (i) of this AD: Additional guidance for repair of the moisture seal can be found in PPG Aerospace Transparencies Abbreviated Component Maintenance Manual, Part Number NP-157901, Revision 6, dated June 16, 2015; and PPG Sierracin Component Maintenance Manual, 56-10-12, Part Number 802600, Revision D, dated April 6, 2017.
Within 8,000 flight hours or 60 months after the effective date of this AD, whichever occurs first: Re-torque the windshield heater terminal lug screws for the left and right windshields and apply Humiseal to the screw heads of the windshield heaters, in accordance with paragraph 3.B., “Procedure,” of the Accomplishment Instructions of Bombardier Service Bulletin 84-30-16, Revision A, dated September 27, 2017.
