Airworthiness Directive · Amendment 39-19559 · Wings
The Boeing Company Airplanes
(1) This AD applies to all The Boeing Company Model 737-600, -700, -700C, -800, -900, and -900ER series airplanes, certificated in any category, as specified in paragraphs (c)(1)(i) through (c)(1)(iii) of this AD.
(i) Airplanes in Groups 1 and 2 as identified in Boeing Alert Service Bulletin 737-57A1327, Revision 2, dated July 25, 2017 (“BASB 737-57A1327, R2”).
(ii) Airplanes in Group 3, as identified in BASB 737-57A1327, R2, except where this service bulletin specifies the groups as line numbers 6422 through 6465 inclusive, this AD specifies those groups as line number 6422 through any line number airplane with an original Certificate of Airworthiness or an original Export Certificate of Airworthiness dated on or before the effective date of this AD.
(iii) All Model 737-600, -700, -700C, -800, -900 and -900ER series airplanes with an original Certificate of Airworthiness or an original Export Certificate of Airworthiness dated after the effective date of this AD.
(2) Installation of Supplemental Type Certificate (STC) ST00830SE does not affect the ability to accomplish the actions required by this AD. Therefore, for airplanes on which STC ST00830SE is installed, a “change in product” alternative method of compliance (AMOC) approval request is not necessary to comply with the requirements of 14 CFR 39.17.
We are superseding Airworthiness Directive (AD) 2017-16-05, which applied to certain The Boeing Company Model 737-600, -700, -700C, -800, -900, and -900ER series airplanes. AD 2017-16-05 required a one- time detailed visual inspection for discrepancies in the Krueger flap bullnose attachment hardware, and related investigative and corrective actions if necessary. This AD adds airplanes and an additional inspection to determine if any Krueger flap no. 1, 2, 3, or 4 has been replaced, and related investigative and corrective actions. Since this is a rotable parts issue, the applicability of this AD has been expanded beyond the airplanes listed in the related service bulletin to include all airplanes on which a Krueger flap bullnose may be installed. This AD was prompted by a report of a Krueger flap bullnose departing an airplane during taxi, which caused damage to the wing structure and thrust reverser, and a report of a missing no. 2 Krueger flap bullnose hinge bolt from an airplane that was not included in the effectivity of AD 2017-16-05. We are issuing this AD to address the unsafe condition on these products.
For airplanes identified in paragraphs (c)(1)(i) and (c)(1)(ii) of this AD: Except as required by paragraph (h) of this AD, at the applicable times specified in paragraph 1.E., “Compliance,” of BASB 737-57A1327, R2, do all applicable actions identified as “RC” (required for compliance) in, and in accordance with, the Accomplishment Instructions of BASB 737-57A1327, R2.
(1) For purposes of determining compliance with the requirements of this AD: Where BASB 737-57A1327, R2 uses the phrase “the original issue date of this service bulletin,” this AD requires using September 22, 2017 (the effective date of AD 2017-16-05).
(2) For purposes of determining compliance with the requirements of this AD: Where BASB 737-57A1327, R2 uses the phrase “the Revision 2 date of this service bulletin,” this AD requires using “the effective date of this AD.”
As of the effective date of this AD, no person may install a Krueger flap or Krueger flap bullnose on any airplane identified in paragraph (c)(1)(i), (c)(1)(ii), or (c)(1)(iii) of this AD, unless the actions required by paragraph (g) of this AD have been accomplished on the Krueger flap bullnose after installation but prior to further flight. These actions are required only for the Krueger flap(s) or Krueger flap bullnose(s) being installed.
