Skip to Content

Proposed Rule

Airworthiness Directives; Boeing Model 727 Series Airplanes

Document Details

Information about this document as published in the Federal Register.

Published Document

This document has been published in the Federal Register. Use the PDF linked in the document sidebar for the official electronic format.

Start Preamble

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes the supersedure of 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 action would expand the area to be inspected; require accomplishment of the previously optional (and subsequently revised) modification, which would terminate certain repetitive inspections; and add repetitive post-modification inspections to detect cracking of the fastener holes, and corrective actions if necessary. The actions specified by the proposed 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.

DATES:

Comments must be received by June 16, 2003.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2002-NM-66-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9 a.m. and 3 p.m., Monday through Friday, except Federal holidays. Comments may be submitted via fax to (425) 227-1232. Comments may also be sent via the Internet using the following address: 9-anm-nprmcomment@faa.gov. Comments sent via fax or the Internet must contain “Docket No. 2002-NM-66-AD” in the subject line and need not be submitted in triplicate. Comments sent via the Internet as attached electronic files must be formatted in Microsoft Word 97 for Windows or ASCII text.

The service information referenced in the proposed rule may be obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124-2207. This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington.

Start Further Info

FOR FURTHER INFORMATION CONTACT:

Ivan Li, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 917-6437; fax (425) 917-6590.

End Further Info End Preamble Start Supplemental Information

SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to participate in the making of the proposed rule by submitting such written data, views, or arguments as they may desire. Communications shall identify the Rules Docket number and be submitted in triplicate to the address specified above. All communications received on or before the closing date for comments, specified above, will be considered before taking action on the proposed rule. The proposals contained in this action may be changed in light of the comments received.

Submit comments using the following format:

  • Organize comments issue-by-issue. For example, discuss a request to change the compliance time and a request to change the service bulletin reference as two separate issues.
  • For each issue, state what specific change to the proposed AD is being requested.
  • Include justification (e.g., reasons or data) for each request.

Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the proposed rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by Start Printed Page 23232interested persons. A report summarizing each FAA-public contact concerned with the substance of this proposal will be filed in the Rules Docket.

Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this action must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket Number 2002-NM-66-AD.” The postcard will be date stamped and returned to the commenter.

Availability of NPRMs

Any person may obtain a copy of this NPRM by submitting a request to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2002-NM-66-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

On February 21, 1997, the FAA issued AD 97-05-08, amendment 39-9952 (62 FR 9359, March 3, 1997), applicable to all Boeing Model 727 series airplanes, to require 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. Accomplishment of those optional actions would terminate the repetitive pre-modification inspections. That action was prompted by reports indicating that fatigue cracks were found in the forward support fitting of the number 1 and number 3 engines. The requirements of that AD are intended to detect and correct such fatigue cracking, which could result in failure of the support fitting and consequent separation of the engine from the airplane.

Actions Since Issuance of Previous AD

Since that AD was issued, the FAA has received reports of additional cracking found on the forward support fitting of the number 1 and number 3 engines on Boeing Model 727 series airplanes. Those cracks were found at new locations (not identified in AD 97-05-08) on airplanes that had accumulated between 18,200 and 44,200 total flight cycles. The cracking has been attributed to fatigue due to corrosion-pitting damage on the surface of fastener holes in the support fittings.

Explanation of Relevant Service Information

The FAA has reviewed and approved Boeing Service Bulletin 727-54A0010, Revision 6, dated August 23, 2001, including an Evaluation Form. Revision 4 of the service bulletin was cited as the appropriate source of service information for accomplishment of the actions required by AD 97-05-08. Revision 5 was issued to divide the airplane effectivity into two groups, add more locations to be inspected, add inspections until the terminating action is accomplished, revise the instructions for the modification, and add post-modification repetitive inspections. Revision 6 was issued to change part numbers for certain fasteners and revise the repetitive intervals for inspection of the upper outboard flange. Accomplishment of the actions specified in Revision 6 is intended to adequately address the identified unsafe condition.

Explanation of Requirements of Proposed Rule

Since an unsafe condition has been identified that is likely to exist or develop on other products of this same type design, the proposed AD would supersede AD 97-05-08 to continue to require repetitive inspections to detect cracking in the forward support fitting of the number 1 and number 3 engines. This proposed AD also would expand the area to be inspected; require accomplishment of the previously optional (and subsequently revised) modification, which would terminate certain repetitive inspections; and add repetitive post-modification inspections to detect cracking of the fastener holes, and corrective action if necessary. The actions would be required to be accomplished in accordance with Revision 6 of the service bulletin described previously.

Differences Between Proposed AD and Service Information

Although the service bulletin specifies that Boeing may be contacted for disposition of certain repair conditions, this proposal would require the repair of those conditions to be accomplished in accordance with a method approved by the FAA, or in accordance with data meeting the type certification basis of the airplane approved by a Boeing Company Designated Engineering Representative who has been authorized by the FAA to make such findings.

Although the service bulletin recommends that operators submit a completed Evaluation Form and a report of damage that exceeds certain limits, this proposed AD would not require such reports.

Explanation of Proposed Change to Existing Requirements

The FAA has changed all references to a “detailed visual inspection” in the existing AD to “detailed inspection” in this proposed AD. Note 2 has been added to this proposed AD to define this type of inspection.

Cost Impact

There are approximately 1,382 airplanes of the affected design in the worldwide fleet. The FAA estimates that 915 airplanes of U.S. registry would be affected by this proposed AD.

The FAA provides the following cost estimates for this proposed AD:

ActionWork hoursAverage hourly labor rateParts costCost per airplaneNumber of U.S. airplanesU.S. fleet cost
AD 97-05-08 inspections, per inspection cycle2$60$0$120915None.
Inspections before structural rework, per inspection cycle14600840915768,600
Structural rework7607,8758,2959157,589,925
Inspections after structural rework, per inspection cycle12600720915658,800

The cost impact figures discussed above are based on assumptions that no operator has yet accomplished any of the proposed requirements of this AD action, and that no operator would accomplish those actions in the future if this proposed AD were not adopted. The cost impact figures discussed in AD rulemaking actions represent only the time necessary to perform the specific actions actually required by the AD. These figures typically do not include incidental costs, such as the time required to gain access and close up, Start Printed Page 23233planning time, or time necessitated by other administrative actions.

Regulatory Impact

The regulations proposed herein would not have a substantial direct effect on the States, on the relationship between the national Government and the States, or on the distribution of power and responsibilities among the various levels of government. Therefore, it is determined that this proposal would not have federalism implications under Executive Order 13132.

For the reasons discussed above, I certify that this proposed regulation (1) is not a “significant regulatory action” under Executive Order 12866; (2) is not a “significant rule” under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) if promulgated, will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. A copy of the draft regulatory evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting the Rules Docket at the location provided under the caption ADDRESSES.

Start List of Subjects

List of Subjects in 14 CFR Part 39

End List of Subjects

The Proposed Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows:

Start Part

PART 39—AIRWORTHINESS DIRECTIVES

1. The authority citation for part 39 continues to read as follows:

Start Authority

Authority: 49 U.S.C. 106(g), 40113, 44701.

End Authority
[Amended]

2. Section 39.13 is amended by removing amendment 39-9952 (62 FR 9359, March 3, 1997), and by adding a new airworthiness directive (AD), to read as follows:

Boeing: Docket 2002-NM-66-AD. Supersedes AD 97-05-08, Amendment 39-9952.

Applicability: 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 (s)(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.

Compliance: Required as indicated, unless accomplished previously.

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:

Restatement of Requirements of AD 97-05-08

Inspections

(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 defined as: “An intensive visual examination of a specific structural area, system, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at intensity deemed appropriate by the inspector. Inspection aids such as mirror, magnifying lenses, etc., may be used. Surface cleaning and elaborate access 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.

New Requirements of This AD

Note 3:

Where there are differences between the service bulletin and this AD, this AD prevails.

Inspections: All Airplanes

(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 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 defined as: “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 enhance visual access to all exposed 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 a 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 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.

(5) Perform detailed and HFEC inspections to detect cracking of the upper and lower Start Printed Page 23234horizontal flanges at the side of the body, in accordance with Figure 1 of the service bulletin.

Additional Inspections: Group 2 Airplanes

(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 a HFEC inspection to detect cracking of the aft side of the lower horizontal flange, in accordance with Figure 1 of the service bulletin.

No Cracking Found: Follow-on Inspections, All Airplanes

(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.

No Cracking Found: Additional Follow-on Inspections, Group 2 Airplanes

(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.

Cracking Found: Any Airplane

(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 per data meeting the type certification basis of the airplane approved by a Boeing Company Designated Engineering Representative (DER) who has been authorized by the Manager, Seattle ACO, to make such findings. For a repair method to be approved, the approval must refer specifically to this AD; or

(2) Do the modification specified in paragraph (j) of this AD.

Web Thickness Less Than 0.130 Inch: Any Airplane

(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 per data meeting the type certification basis of the airplane approved by a Boeing Company DER who has been authorized by the Manager, Seattle ACO, to make such findings. For a repair method to be approved, the approval must refer specifically to this AD.

Modification

(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.

Modification per Prior Service Bulletin Version

(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) above.

(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.

Post-Modification Inspections

(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 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.

Follow-on/Corrective Actions

(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, excluding the Evaluation Form; except as required by paragraph (q) of this AD.

Exception to Corrective Actions

(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 per a method approved by the Manager, Seattle ACO; or per data meeting the type certification basis of the airplane approved by a Boeing Company DER who has been authorized by the Manager, Seattle ACO, to make such findings. For a repair method to be approved, the approval must refer specifically to this AD.

Note 6:

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 such a reporting requirement.

Spare Parts

(r) 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.

Alternative Methods of Compliance

(s)(1) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Seattle ACO. Operators shall submit their requests through an appropriate FAA Principal Start Printed Page 23235Maintenance Inspector, who may add comments and then send it to the Manager, Seattle ACO.

(2) Alternative methods of compliance previously approved according to AD 97-05-08 are acceptable for compliance with the corresponding requirements of this AD.

Note 7:

Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO.

Special Flight Permits

(t) Special flight permits may be issued according to sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished.

Start Signature

Issued in Renton, Washington, on April 25, 2003.

Ali Bahrami,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.

End Signature End Part End Supplemental Information

[FR Doc. 03-10728 Filed 4-30-03; 8:45 am]

BILLING CODE 4910-13-P