Airworthiness Directive · Amendment 39-14678 · Boeing Model 737-100, -200, and -200C Series Airplanes
Boeing Model 737-100, -200, and -200C Series Airplanes
This AD applies to Boeing Model 737-100, -200, and -200C series airplanes, certificated in any category; as identified in Boeing Alert Service Bulletin 737-55A1078, dated October 27, 2005.
The FAA is superseding an existing airworthiness directive (AD), which applies to certain Boeing Model 737 series airplanes. That AD currently requires inspection of the elevator tab inboard hinge support structure to detect fatigue cracking and corrective action if necessary. That AD also provides an optional terminating action. This new AD adds airplanes to the applicability and requires new repetitive inspections. For airplanes having elevators with laminated rear spars, this new AD requires repetitive inspections for interlaminar corrosion, delamination, or disbonding in the rear spar, repetitive inspections for cracking in the spar web, and repair including related investigative/corrective actions if necessary. For airplanes having elevators with solid rear spars, this new AD requires repetitive inspections for cracking in the spar web and repair including related investigative/corrective actions if necessary. This AD results from reports of cracks in the elevator rear spar web at the tab hinge bracket locations. We are issuing this AD to detect and correct cracking, corrosion, interlaminar corrosion, delamination, and disbonding in the elevator rear spar, which may reduce elevator stiffness and lead to in-flight vibration. In-flight vibration may lead to elevator and horizontal stabilizer damage and reduced controllability of the airplane.
You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.
For Model 737-100, -200, and -200C series airplanes, line number 001 through 491 inclusive: Within the next 300 hours time-in-service after July 24, 1989 (the effective date of AD 76-11-05 R1), unless accomplished within the last 700 hours time-in-service, and at intervals thereafter not to exceed 1,000 hours time-in-service, conduct the inspection required by paragraph (g) of this AD. Accomplishing the initial inspections specified in paragraph (j) of this AD terminates the requirements of this paragraph.
(g) For Model 737-100, -200, and -200C series airplanes, line number 001 through 491 inclusive: At the times specified in paragraph (f) of this AD, inspect for excessive deflection of the elevator tab, right and left hand, in accordance with the inspection procedures specified in Section III, Part I, paragraphs C. and D., of Boeing Alert Service Bulletin 737-55-A1020, Revision 1, dated August 20, 1976; Revision 2, dated February 11, 1977; or 737-55A1020, Revision 3, dated December 22, 1988. If the elevator tab-to-elevator relative deflection exceeds 1/10 inch, prior to further flight, modify the elevator in accordance with paragraph (h) of this AD. Accomplishing the initial inspections specified in paragraph (j) of this AD terminates the requirements of this paragraph.
(h) For Model 737-100, -200, and -200C series airplanes, line number 001 through 491 inclusive: Installation of one of the modifications specified in Boeing Alert Service Bulletin 737-55-A1020, Revision 1, dated August 20, 1976; 737-55-A1020, Revision 2, dated February 11, 1977; or 737-55A1020, Revision 3, dated December 22, 1988; Section III, Part II, including installation of the bolt retainer clips or the preventive modification specified in Boeing Service Bulletin 737-55-1022, Section III, Part II, dated April 15, 1977; is considered terminating action for the inspection requirements of paragraph (g) of this AD.
(i) Within 1,000 flight hours or 750 flight cycles after the effective date of this AD, whichever occurs first, determine the elevator group number or the elevator configuration number in accordance with Appendix A of Boeing Alert Service Bulletin 737-55A1078, dated October 27, 2005.
At the applicable time specified in Tables 2 and 3 of paragraph 1.E. “Compliance” of Boeing Alert Service Bulletin 737-55A1078, dated October 27, 2005, except where the alert service bulletin specifies a compliance time from the release date of the alert service bulletin, this AD requires the compliance time after the effective date of this AD: Do the applicable initial detailed and special detailed inspections for interlaminar corrosion, cracking, delamination, or disbonding in the rear spar by doing all the applicable actions specified in Parts I, II, and III of the Accomplishment Instructions of Boeing Alert Service Bulletin 737-55A1078, dated October 27, 2005; except where step 3. of Part III of the alert service bulletin specifies to do a special detailed inspection for spar interlaminar corrosion as given in Figure 3, this AD requires all actions specified in Figure 3 to be done (a detailed inspection for interlaminar corrosion and disbonding and a special detailed inspection for interlaminar corrosion and delamination). Doing the initial inspections terminates the requirements of paragraphs (f) and (g) of this AD.
(k) Repeat the inspections specified in paragraph (j) of this AD at the applicable time specified in Tables 4 and 5 of paragraph 1.E. “Compliance” of Boeing Alert Service Bulletin 737-55A1078, dated October 27, 2005; except where Table B.4 in Appendix B of the alert service bulletin specifies compliance times in flight hours or flight cycles, this AD requires the actions specified in Table B.4 be done at the earlier of the compliance times in flight hours or flight cycles.
If any interlaminar corrosion, cracking, delamination, or disbonding is found during any inspection required by this AD: Before further flight, use Appendix C of Boeing Alert Service Bulletin 737-55A1078, dated October 27, 2005, to determine the permitted repairs, and do the applicable repair, including related investigative and corrective actions, by doing all the applicable actions specified in Parts IV through VIII (Interim Repairs) and Part IX (Time-limited Repair) of the Accomplishment Instructions of the alert service bulletin, except as provided by paragraphs (n) and (o) of this AD.
(m) If the time-limited repair specified in Part IX of the Accomplishment Instructions of Boeing Alert Service Bulletin 737-55A1078, dated October 27, 2005, is done: At the time specified in Table 6 of paragraph 1.E. “Compliance” of the alert service bulletin, do the applicable repair, including related investigative and corrective actions, by doing all the applicable actions specified in Parts IV through VI (Interim Repairs) of the alert service bulletin. Thereafter, do the repetitive inspections specified in paragraph (k) of this AD.
(n) Where Boeing Alert Service Bulletin 737-55A1078, dated October 27, 2005, specifies to contact the manufacturer for appropriate action for the inspar rib replacement or for more instructions if any crack is outside the limit specified in the service bulletin: Before further flight, repair in accordance with a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA; or using a method approved in accordance with paragraph (p) of this AD.
(o) Where step 3.a. of Part III of the Accomplishment Instructions of Boeing Alert Service Bulletin 737-55A1078, dated October 27, 2005, specifies that if interlaminar corrosion is found, spar replacement is required, this AD requires spar replacement if interlaminar corrosion, delamination, or disbonding is found. Where step 3.C. of Appendix C of the alert service bulletin specifies that for laminated spars that have interlaminar corrosion, only repair options B, C, and D are permitted, this AD specifies that for laminated spars that have interlaminar corrosion, delamination, or disbonding, only repair options B, C, and D are permitted.
