Airworthiness Directive · Amendment 39-16163 · Flight controls
Bombardier, Inc. (Type Certificate Previously Held by de Havilland, Inc.) Model DHC-8-400 Series Airplanes
This AD applies to Bombardier, Inc. (Type Certificate previously held by de Havilland, Inc.) Model DHC-8-400, DHC-8-401, and DHC-8-402 airplanes, certificated in any category, serial numbers 4135 through 4149 inclusive.
We are superseding an existing airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:
Unless already done, do the following actions.
(1) Within 30 days after June 26, 2009 (the effective date of AD 2009-12-13), inspect the serial number of each of the six installed elevator PCUs having P/N 390600-1007. If one or more of the six installed elevator PCUs, P/N 390600-1007, have any of the PCU serial numbers 238, 698, 783 through 788 inclusive, 790, 793, 795, 802, 806, 807, 810, 820 through 823 inclusive, 826 through 828 inclusive, 831, 835, 838, 840, 886 through 889 inclusive, or 898 through 955 inclusive; without a suffix “A” after the serial number: Within 30 days after June 26, 2009, perform a check for the correct operation of all installed elevator PCUs in accordance with the procedures detailed in Appendix A, B, or C of Bombardier Q400 All Operator Message 217B, dated April 26, 2007. Repeat the check thereafter before the first flight of each day until the replacement specified in paragraph (g) of this AD is done. The checks in Appendices A and B of Bombardier Q400 All Operator Message 217B, dated April 26, 2007, must be performed by the flight crew, while the check specified in Appendix C of the all operator message must be performed by certificated maintenance personnel.
Note 1: Suffix “A” after the serial number indicates that the PCU has already passed a magnetic particle inspection and is cleared for continued use.
(2) If incorrect operation of any elevator PCU is found during any check required by paragraph (f)(1) of this AD, before further flight, replace the elevator PCU with a PCU, P/N 390600-1007, having a serial number not specified in paragraph (f)(1) of this AD; or with a PCU, P/N 390600-1007, having the suffix “A” after the serial number; in accordance with the Accomplishment Instructions of Bombardier Service Bulletin 84-27-32, Revision A, dated January 18, 2008.
(3) Actions accomplished before June 26, 2009, according to Bombardier Service Bulletin 84-27-32, dated May 1, 2007, are considered acceptable for compliance with the corresponding action specified in this AD.
Unless already done, within 2,000 flight hours or 12 months after the effective date of this AD, whichever occurs later, replace all PCUs, P/N 390600-1007, having a serial number specified in paragraph (f)(1) of this AD, and not having suffix “A” after the serial number, with PCUs, P/N 390600-1007, having a serial number not specified in paragraph (f)(1) of this AD; or with PCUs, P/N 390600-1007, having the suffix “A” after the serial number; in accordance with the Accomplishment Instructions of Bombardier Service Bulletin 84-27-32, Revision A, dated January 18, 2008. This action terminates the requirements of paragraph (f)(1) of this AD.
Note 2: This AD differs from the MCAI and/or service information as follows: No differences.
