Airworthiness Directive · Amendment 39-14289 · Boeing Model 727 Series Airplanes
Boeing Model 727 Series Airplanes
All Model 727 series airplanes, certificated in any category.
Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (t)(1) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.
This amendment supersedes an existing airworthiness directive (AD), applicable to all Boeing Model 727 series airplanes, that currently requires repetitive pre-modification inspections to detect cracks in the forward support fitting of the number 1 and number 3 engines; and repair, if necessary. That AD also provides for an optional high frequency eddy current inspection, and, if possible, modification of the fastener holes; and various follow-on actions; which would terminate the repetitive pre-modification inspections. This amendment expands the area to be inspected; requires accomplishment of the previously optional (and subsequently revised) modification, which terminates certain repetitive inspections; and adds repetitive post- modification inspections to detect cracking of the fastener holes, and corrective actions if necessary. The actions specified by this AD are intended to prevent fatigue cracking of the forward support fitting of the number 1 and number 3 engines, which could result in failure of the support fitting and consequent separation of the engine from the airplane. This action is intended to address the identified unsafe condition.
To prevent fatigue cracking of the forward support fitting of the number 1 and number 3 engines, which could result in failure of the support fitting and consequent separation of the engine from the airplane, accomplish the following:
(a) Within 100 days or 600 flight cycles after March 18, 1997 (the effective date of AD 97-05-08, amendment 39-9952), whichever occurs first, accomplish paragraphs (a)(1), (a)(2), and (a)(3) of this AD, in accordance with Boeing Service Bulletin 727-54A0010, Revision 4, dated January 30, 1997.
(1) Perform a visual inspection to detect cracks of the upper and lower flanges, and the vertical web of the forward support fitting of the number 1 and number 3 engines, in accordance with Part 1—Pre-Modification Inspections of the Accomplishment Instructions of the service bulletin.
(2) Perform a high frequency eddy current (HFEC) inspection to detect cracks of the forward flange of the support fitting adjacent to the collars of two fasteners of the number 1 and number 3 engines, in accordance with Part 1—Pre-Modification Inspections of the Accomplishment Instructions of the service bulletin.
(3) Perform a detailed inspection to detect cracks of the upper and lower flanges adjacent to six fasteners of the fitting of the number 1 and number 3 engines, in accordance with Part 1—Pre-Modification Inspections of the Accomplishment Instructions of the service bulletin.
Note 2: For the purposes of this AD, a detailed inspection is: “An intensive examination of a specific item, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at an intensity deemed appropriate. Inspection aids such as mirror, magnifying lenses, etc., may be necessary. Surface cleaning and elaborate procedures may be required.”
(b) If no crack is detected during the inspections required by paragraph (a) of this AD, repeat those inspections thereafter at intervals not to exceed 100 days or 600 flight cycles, whichever occurs first, until the initial inspections required by paragraph (d) of this AD have been accomplished.
(c) If any crack is detected during any inspection required by paragraph (a) of this AD, prior to further flight, repair the forward support fitting in accordance with a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA.
Note 3: Where there are differences between the service bulletin and this AD, this AD prevails.
(d) For all airplanes: Within 600 flight cycles or 100 days after the effective date of this AD, whichever occurs first, inspect the forward support fitting of the number 1 and number 3 engines, as specified in paragraphs (d)(1), (d)(2), (d)(3), (d)(4), and (d)(5) of this AD, in accordance with Part I of the Accomplishment Instructions of Boeing Service Bulletin 727-54A0010, Revision 6, dated August 23, 2001. Accomplishment of these initial inspections terminates the inspection requirements of paragraphs (a) and (b) of this AD.
(1) Perform a general visual inspection to detect corrosion and cracking of the fittings in areas inboard of the side of the body, in accordance with Figure 1 of the service bulletin. If any corrosion is found, before further flight, remove the corrosion by accomplishing all of the actions in and in accordance with Figure 5 of the service bulletin, and then perform a general visual inspection to detect cracking of the area, in accordance with the service bulletin.
Note 4: For the purposes of this AD, a general visual inspection is: “A visual examination of an interior or exterior area, installation, or assembly to detect obvious damage, failure, or irregularity. This level of inspection is made from within touching distance unless otherwise specified. A mirror may be necessary to ensure visual access to all surfaces in the inspection area. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight, or droplight and may require removal or opening of access panels or doors. Stands, ladders, or platforms may be required to gain proximity to the area being checked.”
(2) Perform an HFEC inspection to detect cracking of the upper and lower horizontal flanges and post tangs of the fittings from inside the airplane, in accordance with Figure 1 of the service bulletin.
(3) Perform a general visual inspection to detect cracking and corrosion of the fittings in areas outboard of the side of the body, in accordance with Figure 1 of the service bulletin. If any corrosion is found, before further flight, remove the corrosion by accomplishing all of the actions in and in accordance with Figure 5 of the service bulletin, and perform a general visual inspection to detect cracking of the area, in accordance with the service bulletin.
(4) Perform a detailed inspection to detect cracking and corrosion of the web in areas outboard of the side of the body, in accordance with Figure 1 of the service bulletin. If any corrosion is found, before further flight, remove the corrosion in accordance with Figure 5 of the service bulletin, and perform thickness measurements and detailed and HFEC inspections of the vertical web inboard and outboard of the side of the body to detect corrosion and cracking, in accordance with Figure 2 of the service bulletin. If the web thickness is less than 0.130 inch, do paragraph (i) of this AD.
(5) Perform detailed and HFEC inspections to detect cracking of the upper and lower horizontal flanges at the side of the body, in accordance with Figure 1 of the service bulletin.
(e) For Group 2 airplanes, as identified in Boeing Service Bulletin 727-54A0010, Revision 6, dated August 23, 2001: Within 600 flight cycles or 100 days after the effective date of this AD, whichever occurs first, inspect the forward support fitting of the number 1 and number 3 engines at the firewall to detect cracking, as specified in paragraphs (e)(1), (e)(2), (e)(3), and (e)(4) of this AD, in accordance with Part I of the Accomplishment Instructions of the service bulletin.
(1) Perform a detailed inspection to detect cracking of the aft side of the upper horizontal flange, in accordance with Figure 1 of the service bulletin.
(2) Perform a low frequency eddy current (LFEC) or an open hole HFEC inspection to detect cracking of the aft side of the upper horizontal flange, in accordance with Figure 1 of the service bulletin.
(3) Perform a detailed inspection to detect cracking of the aft side of the lower horizontal flange, in accordance with Figure 1 of the service bulletin.
(4) Perform an HFEC inspection to detect cracking of the aft side of the lower horizontal flange, in accordance with Figure 1 of the service bulletin.
(f) For all airplanes: If no cracking is found during any inspection required by paragraph (d) of this AD, repeat the applicable inspections within the applicable intervals specified in paragraph 1.E., Table 1, of Boeing Service Bulletin 727-54A0010, Revision 6, dated August 23, 2001, until the modification required by paragraph (j) of this AD has been done.
(g) For Group 2 airplanes only: If no cracking is found during the inspections required by paragraph (e) of this AD, repeat the inspections on the upper and lower outboard flange at the firewall within the applicable intervals specified in paragraph 1.E., Table 1, of Boeing Service Bulletin 727-54A0010, Revision 6, dated August 23, 2001.
(1) Repeat the inspections of the upper outboard flange at the firewall until the modification required by paragraph (j) of this AD has been done.
(2) Repeat the inspections of the lower outboard flange at the firewall indefinitely. There is no terminating action for the inspections of this area.
Note 5: Boeing Service Bulletin 727-54A0010, Revision 6, dated August 23, 2001, does not provide instructions for modifying the fastener holes of the lower outboard flange at the firewall.
(h) For any airplane: If any crack is found during any inspection required by paragraph (d), (e), (f), or (g) of this AD, before further flight, do the actions specified in either paragraph (h)(1) or (h)(2) of this AD.
(1) Replace or repair the fitting in accordance with a method approved by the Manager, Seattle ACO; or according to data meeting the certification basis of the airplane approved by an Authorized Representative for the Boeing Delegation Option Authorization (DOA) Organization who has been authorized by the Manager, Seattle ACO, to make those findings. For a repair method to be approved, the repair must meet the certification basis of the airplane, and the approval must specifically refer to this AD; or
(2) Do the modification specified in paragraph (j) of this AD.
(i) For any airplane: If the web thickness measured during accomplishment of paragraph (d)(4) of this AD is less than 0.130 inch, before further flight, replace or repair the fitting in accordance with a method approved by the Manager, Seattle ACO; or according to data meeting the certification basis of the airplane approved by an Authorized Representative for the Boeing DOA Organization who has been authorized by the Manager, Seattle ACO, to make those findings. For a repair method to be approved, the repair must meet the certification basis of the airplane, and the approval must specifically refer to this AD.
(j) Except as required by paragraphs (h), (i), and (q) of this AD: Within 3,000 flight cycles or 24 months after the effective date of this AD, whichever occurs first, modify the fastener holes, in accordance with Part II of the Accomplishment Instructions of Boeing Service Bulletin 727-54A0010, Revision 6, dated August 23, 2001. Accomplishment of the modification terminates the repetitive inspections required by paragraphs (f) and (g)(1) of this AD.
(k) For airplanes modified before the effective date of this AD in accordance with Boeing Service Bulletin 727-54A0010, Revision 4, dated January 30, 1997: Paragraph (j) of this AD requires accomplishment of additional procedures in accordance with Revision 6 of the service bulletin. To the extent that certain modification procedures were performed in accordance with Revision 4, those actions do not need to be repeated when performing the modification required in paragraph (j) of this AD.
(l) A modification done before the effective date of this AD in accordance with Boeing Alert Service Bulletin 727-54A0010, Revision 5, dated February 15, 2001, is acceptable for compliance with the requirements of paragraph (j) of this AD.
(m) Inspect as specified in paragraphs (m)(1), (m)(2), and (n) of this AD, as applicable, to detect cracking and corrosion, in accordance with Part III of the Accomplishment Instructions of Boeing Service Bulletin 727-54A0010, Revision 6, dated August 23, 2001. Inspections done before the effective date of this AD in accordance with Part III of Boeing Alert Service Bulletin 727-54A0010, Revision 5, dated February 15, 2001, are acceptable for compliance with the corresponding inspection requirements of this paragraph.
(1) For all airplanes: Do an open hole HFEC inspection of the fastener holes in the forward support fitting of the number 1 and number 3 engines, at the locations shown in Figure 4 of the service bulletin.
(2) For Group 2 airplanes: Do an open hole HFEC inspection of the fastener holes in the forward support fitting of the number 1 and number 3 engines, at the locations shown in Figure 4 of the service bulletin.
(n) Perform the inspections specified in paragraph (m) of this AD at the later of the times specified in paragraphs (n)(1) and (n)(2) of this AD.
(1) Within 3,000 flight cycles or 24 months, whichever occurs first, after accomplishment of the modification required by paragraph (j) of this AD.
(2) Within 600 flight cycles or 100 days, whichever occurs first, after the effective date of this AD.
(o) If no cracking is found during any inspection required by paragraph (m) of this AD: Repeat the inspections specified in paragraph (m) of this AD thereafter within the applicable intervals specified in paragraph 1.E., Table 1, of Boeing Service Bulletin 727-54A0010, Revision 6, dated August 23, 2001. Accomplishment of the modification specified in paragraph (j) of this AD does not terminate the requirement to repetitively perform the post-modification inspections specified in Part III of the service bulletin.
(p) If any cracking is detected during any inspection required by paragraph (m) of this AD: Before further flight, repair in accordance with Boeing Service Bulletin 727-54A0010, Revision 6, dated August 23, 2001; except as required by paragraph (q) of this AD.
(q) Where Boeing Service Bulletin 727-54A0010, Revision 6, dated August 23, 2001, specifies to contact Boeing for appropriate action: Before further flight, replace or repair the fitting in accordance with a method approved by the Manager, Seattle ACO; or according to data meeting the certification basis of the airplane approved by an Authorized Representative for the Boeing DOA Organization who has been authorized by the Manager, Seattle ACO, to make those findings. For a repair method to be approved, the repair must meet the certification basis of the airplane, and the approval must specifically refer to this AD.
(r) Boeing Service Bulletin 727-54A0010, Revision 6, dated August 23, 2001, recommends that operators report inspection results to the manufacturer; however, this AD does not contain this requirement.
(s) As of the effective date of this AD, no person may install a forward support fitting on any airplane, unless it has been inspected and modified, as applicable, in accordance with the requirements of this AD.
(t)(1) The Manager, Seattle ACO, FAA, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19.
(2) AMOCs previously approved according to AD 97-05-08 are acceptable for compliance with the corresponding requirements of this AD.
(3) An AMOC that provides an acceptable level of safety may be used for any repair required by this AD, if it is approved by an Authorized Representative for the Boeing DOA Organization who has been authorized by the Manager, Seattle ACO, to make those findings. For a repair method to be approved, the repair must meet the certification basis of the airplane, and the approval must specifically refer to this AD.
Note 6: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO.
