E6-11805. Airworthiness Directives; McDonnell Douglas Model DC-8-55, DC-8F-54, and DC-8F-55 Airplanes; and DC-8-60, DC-8-70, DC-8-60F, and DC-8-70F Series Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Supplemental notice of proposed rulemaking; reopening of comment period.

SUMMARY:

This document revises an earlier proposed airworthiness directive (AD), applicable to certain McDonnell Douglas Model DC-8 airplanes. That proposed AD would have required a one-time inspection for cracks of the aft fuselage skin panel at the longeron 28 skin splice; repair of any cracks detected; and reporting of the findings of the inspection to the manufacturer. This new action revises the proposed AD by removing airplanes from the applicability; and adds repetitive inspections for cracks in the same area, a one-time inspection for previous repairs, and repair if necessary. This new action also would require reporting the inspection findings to the manufacturer, and would provide optional actions for extending the repetitive inspection intervals. The requirements proposed by this new action are intended to detect and correct cracks in the aft fuselage skin at the longeron 28 skin splice, which could lead to loss of structural integrity of the aft fuselage, resulting in rapid decompression of the airplane. This action is intended to address the identified unsafe condition.

DATES:

Comments must be received by August 21, 2006.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2001-NM-183-AD, 1601 Lind Avenue, SW., Renton, Washington 98057-3356. 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 [phone]. Comments may also be sent via the Internet using the following address: [e-mail]. Comments sent via fax or the Internet must contain “Docket No. 2001-NM-183-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 or 2000 or ASCII text.

The service information referenced in the proposed AD may be obtained from Boeing Commercial Airplanes, Long Beach Division, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Data and Service Management, Dept. C1-L5A (D800-0024). This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California.

FOR FURTHER INFORMATION CONTACT:

Jon Mowery, Aerospace Engineer, Airframe Branch, ANM-120L, FAA, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California 90712-4137; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to participate in the making of the proposed AD 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 AD. 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 AD. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report summarizing each FAA-public contact concerned with the substance of this proposed AD 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 2001-NM-183-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. 2001-NM-183-AD, 1601 Lind Avenue, SW., Renton, Washington 98057-33056.

Discussion

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to add an airworthiness directive (AD), applicable to certain McDonnell Douglas Model DC-8-11, DC-8-12, DC-8-21, DC-8-31, DC-8-32, DC-8-33, DC-8-41, DC-8-42, and DC-8-43 airplanes; DC-8-50 series airplanes; DC-8F-54 and DC-8F-55 airplanes; DC-8-60 series airplanes; DC-8-60F series airplanes; DC-8-70 series airplanes; and DC-8-70F series airplanes; all with flat aft pressure bulkheads; was published as a notice of proposed rulemaking (NPRM) in the Federal Register on October 8, 2003 (68 FR 58044). That NPRM would have required a one-time inspection of the aft fuselage skin panel at the longeron 28 skin splice for cracks; repair of any cracks detected; and reporting of the findings of the inspection to the manufacturer. That NPRM was prompted by a report indicating that a crack was found in the aft fuselage skin at the longeron 28 skin splice just forward of the aft pressure bulkhead. That condition, if not corrected, could lead to loss of structural integrity of the aft fuselage, resulting in rapid decompression of the airplane.

Actions Since Issuance of Previous Proposal

Since the issuance of that NPRM, Boeing has issued a service bulletin that addresses the unsafe condition. No service bulletin was cited as part of the actions in the original NPRM. In that NPRM we stated that the manufacturer was developing service information which could include repetitive inspections and repairs. The manufacturer has now released that service bulletin and this supplemental NPRM results from that new service information.

In addition, we received one comment regarding the procedures in the original NPRM. Due consideration has been given to the one comment received in response to the NPRM.

Request To Withdraw the NPRM

UPS requests that we withdraw the original NPRM because it believes the one crack it found in its fleet was an isolated incident that does not indicate an unsafe condition exists for the remaining fleet.

We disagree. Since the original NPRM was released, two other operators reported cracks in the same area. We have not changed the supplemental NPRM in this regard.

Explanation of Relevant Service Information

We have reviewed Boeing Alert Service Bulletin DC8-53A080, dated June 22, 2004. This service bulletin describes procedures for a one-time visual inspection to determine if there are previous repairs of the aft fuselage skin panel at the longeron 28 skin splice.

For areas that have not been previously repaired, the service bulletin describes procedures for repetitive general visual inspections and high-frequency eddy current (HFEC) inspections for discrepancies of the unrepaired areas; and repair if necessary. Discrepancies can include distortion, damage, cracks, corrosion, and loose parts. The service bulletin specifies doing the inspections at longeron 28 between the bolted connection of the tail section to forward of the flat aft pressure bulkhead, on both the left and right sides.

The service bulletin gives operators options for three HFEC inspection types: HFEC magneto-optic/eddy current imager, HFEC surface probe, and HFEC sliding probe. The service bulletin also describes procedures for related investigative and corrective actions if necessary. The related investigative action is a visual inspection for cracks of fasteners adjacent to detected skin cracks. The corrective action is replacing failed fasteners or repairing the skin crack locally, as applicable. The service bulletin also describes procedures for reporting inspection findings to the manufacturer.

For areas that have been previously repaired, the service bulletin specifies that operators should remove the previous repairs within 2 years after the general visual inspection, and install a local repair in accordance with Boeing DC-8 Service Rework Drawing SR08530032, dated January 13, 2004, including Boeing Parts List PL SR08530032, dated January 7, 2004, Boeing Advance Engineering Order, Advanced Drawing Change A, dated April 1, 2004, and Boeing Engineering Order, dated January 13, 2004; or contact Boeing for disposition.

Installing a full-length preventive modification, doing a full-length repair, or doing a local repair, terminates the repetitive inspections specified in this supplemental NPRM for un-repaired areas. After installing the preventive modification, full-length repair, or local repair, the service bulletin specifies repetitive external visual, general visual, HFEC, or low-frequency eddy current inspections, as applicable, for discrepancies of the repaired areas, along all four edges of the doubler. The service bulletin specifies doing the repetitive inspections in accordance with the service rework drawing or the service bulletin, as applicable; and repairing any discrepancy in accordance with the service rework drawing or the service bulletin, as applicable. Accomplishment of the actions specified in the service bulletin is intended to adequately address the identified unsafe condition.

Difference Between Supplemental NPRM and Service Bulletin

The service bulletin specifies to contact the manufacturer for instructions on how to repair certain conditions, but this supplemental NPRM would require repairing those conditions in one of the following ways:

• Using a method that we approve; or
• Using data that meet the certification basis of the airplane, and that have been approved by an Authorized Representative for the Boeing Commercial Airplanes Delegation Option Authorization Organization whom we have authorized to make those findings.

Reporting Requirements

This supplemental NPRM would require that operators report the positive results of the inspections to the FAA. Because the cause of the cracking is not known, these required inspection reports will help determine the extent of the cracking in the affected fleet. Based on the results of these reports, we may determine that further corrective action is warranted.

Explanation of Changes to Applicability

We have revised the applicability of the original NPRM to exclude certain airplanes. McDonnell Douglas Model DC-8-11, DC-8-12, DC-8-21, DC-8-31, DC-8-32, DC-8-33, DC-8-41, DC-8-42, and DC-8-43 airplanes; and certain DC-8-50 series airplanes; were included in the original NPRM. We have determined that these airplanes are not subject to the unsafe condition addressed by this proposed AD. Boeing's service bulletin further defines the airplane models that are affected by this proposed AD.

We have also revised the applicability of the original NPRM to identify model designations as published in the most recent type certificate data sheet for the affected models.

Explanation of Additional Changes Made to the NPRM

Boeing Commercial Airplanes has received a Delegation Option Authorization (DOA). We have revised this action to delegate the authority to approve an alternative method of compliance for any repair required by this AD to an Authorized Representative for the Boeing Commercial Airplanes DOA rather than a Designated Engineering Representative (DER).

We have revised this action to clarify the appropriate procedure for notifying the principal inspector before using any approved Alternative Method of Compliance (AMOC) on any airplane to which the AMOC applies.

After the original NPRM was issued, we reviewed the figures we have used over the past several years to calculate AD costs to operators. To account for various inflationary costs in the airline industry, we find it necessary to increase the labor rate used in these calculations from $65 per work hour to $80 per work hour. The cost impact information, below, reflects this increase in the specified hourly labor rate.

Clarification of Inspection Language

Where the Accomplishment Instructions of the Boeing service bulletin specify doing a visual inspection, this supplemental NPRM calls that inspection a “general visual inspection.” A definition of a general visual inspection is included in a note in the regulatory text.

Conclusion

Since these changes expand the scope of the originally proposed AD, the FAA has determined that it is necessary to reopen the comment period to provide additional opportunity for public comment.

Cost Impact

There are approximately 508 airplanes of the affected design in the worldwide fleet. The FAA estimates that 244 airplanes of U.S. registry would be affected by this proposed AD, that it would take between 2 and 4 work hours per airplane to do the initial inspection to see if a doubler is installed, and that the average labor rate is $80 per work hour. Based on these figures, the cost impact of the proposed AD on U.S. operators is estimated to be between $39,040 and $78,080, or between $160 and $320 per airplane.

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 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, planning time, or time necessitated by other administrative actions.

Authority for This Rulemaking

Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, Section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the Agency's authority.

We are issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701, “General requirements.” Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.

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.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Safety

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:

PART 39—AIRWORTHINESS DIRECTIVES

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

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

§ 39.13

[Amended]

2. Section 39.13 is amended by adding the following new airworthiness directive:

McDonnell Douglas: Docket 2001-NM-183-AD.

Applicability: McDonnell Douglas Model DC-8-55, DC-8F-54, DC-8F-55, DC-8-61, DC-8-62, DC-8-63, DC-8-61F, DC-8-62F, DC-8-63F, DC-8-71, DC-8-72, DC-8-73, DC-8-71F, DC-8-72F, and DC-8-73F airplanes; certificated in any category; as identified in Boeing Alert Service Bulletin DC8-53A080, dated June 22, 2004.

Compliance: Required as indicated, unless accomplished previously.

To detect and correct cracks in the aft fuselage skin at the longeron 28 skin splice, which could lead to loss of structural integrity of the aft fuselage, resulting in rapid decompression of the airplane; accomplish the following:

One-Time Inspection for Previous Repairs

(a) For all airplanes: At the applicable time in paragraph (a)(1) or (a)(2) of this AD, do a general visual inspection to determine if there are previous repairs of the aft fuselage skin panel at the longeron 28 skin splice; in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin DC8-53A080, dated June 22, 2004. Then do the applicable actions in paragraphs (b) and (c) of this AD.

(1) For airplanes that have accumulated fewer than 24,000 total flight cycles as of the effective date of this AD: Within 24 months after the effective date of this AD or prior to accumulating 24,000 total flight cycles, whichever occurs later.

(2) For airplanes that have accumulated 24,000 total flight cycles or more as of the effective date of this AD: Within 12 months after the effective date of this AD.

Note 1:

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.”

Repetitive Inspections for Areas That Do Not Have a Previous Repair

(b) For areas that do not have a previous repair: Before further flight after the initial inspection in paragraph (a) of this AD, do general visual and high-frequency eddy current (HFEC) inspections for discrepancies of the unrepaired areas at longeron 28 between the bolted connection of the tail section to forward of the flat aft pressure bulkhead, on both the left and right sides, and do all applicable related investigative and corrective actions before further flight. Do all actions in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin DC8-53A080, dated June 22, 2004. Repeat the inspections thereafter at intervals not to exceed 2,000 flight cycles until an optional action in paragraph (d) of this AD is accomplished.

Repetitive Inspections and Repair for Areas That Have a Previous Repair

(c) For areas that have a previous repair: Within 24 months after accomplishing the initial inspection in paragraph (a) of this AD, remove the previous repair(s), and install a local repair, in accordance with Boeing DC-8 Service Rework Drawing SR08530032, dated January 13, 2004, including Boeing Parts List PL SR08530032, dated January 7, 2004, Boeing Advance Engineering Order, Advanced Drawing Change A, dated April 1, 2004, and Boeing Engineering Order, dated January 13, 2004. Do the inspections in paragraph (d) of this AD thereafter at the applicable interval time specified in paragraph (d)(1) or (d)(2) of this AD.

Optional Actions, Extended Repetitive Inspection Intervals

(d) Installing a full-length preventive modification, doing a full-length repair, or doing a local repair, in accordance with Boeing DC-8 Service Rework Drawing SR08530032, dated January 13, 2004, including Boeing Parts List PL SR08530032, dated January 7, 2004, Boeing Advance Engineering Order, Advanced Drawing Change A, dated April 1, 2004, and Boeing Engineering Order, dated January 13, 2004, ends the repetitive inspection intervals in paragraph (b) of this AD; repeat the inspection thereafter at the applicable interval in paragraph (d)(1) or (d)(2) of this AD.

(1) For airplanes that have internal finger doublers: Within 30,000 flight cycles after doing the optional action, do general visual and HFEC inspections for discrepancies of the unrepaired areas at longeron 28 between the bolted connection of the tail section to forward of the flat aft pressure bulkhead, on both the left and right sides, and do all applicable related investigative and corrective actions before further flight. Do all actions in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin DC8-53A080, dated June 22, 2004. Repeat the inspections thereafter at intervals not to exceed 5,000 flight cycles.

(2) For airplanes that do not have internal finger doublers: Use the applicable intervals and inspections in paragraph (d)(2)(i) or (d)(2)(ii) of this AD.

(i) For repairs (full-length preventive modification, doing a full-length repair, or doing a local repair) that are 12 inches or less along the longeron: Within 15,000 flight cycles after doing the optional action, use only the external general visual inspection method for discrepancies of the unrepaired areas at longeron 28 between the bolted connection of the tail section to forward of the flat aft pressure bulkhead, on both the left and right sides, and do all applicable related investigative and corrective actions before further flight. Do all actions in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin DC8-53A080, dated June 22, 2004. Repeat the external general visual inspection thereafter at intervals not to exceed 5,000 flight cycles.

(ii) For repairs (full-length preventive modification, doing a full-length repair, or doing a local repair) that are more than 12 inches in length along the longeron: Within 15,000 flight cycles after doing the optional action, use only the low-frequency eddy current (LFEC) inspection method for cracks of the unrepaired areas at longeron 28 between the bolted connection of the tail section to forward of the flat aft pressure bulkhead, on both the left and right sides, and do all applicable related investigative and corrective actions before further flight. Do all actions in accordance with Boeing DC-8 Service Rework Drawing SR08530032, dated January 13, 2004, including Boeing Parts List PL SR08530032, dated January 7, 2004, Boeing Advance Engineering Order, Advanced Drawing Change A, dated April 1, 2004, and Boeing Engineering Order, dated January 13, 2004. Repeat the LFEC inspection thereafter at intervals not to exceed 10,000 flight cycles, using only LFEC inspection outward along all four edges of the doubler.

Reporting of Results

(e) Submit a report of positive findings of the inspections required by paragraph (b) and (d) of this AD to Boeing Commercial Airplanes, Manager, Structure/Payloads, Technical and Fleet Support, Service Engineering/Commercial Aviation Services, Long Beach Division, 3855 Lakewood Boulevard, Long Beach, California 90846, at the applicable time specified in paragraph (e)(1) or (e)(2) of this AD. The report must include the inspection results, a description of any discrepancies found, the airplane fuselage number, and the total number of landings and flight hours on the airplane. Information collection requirements contained in this AD have been approved by the Office of Management and Budget (OMB) under the provisions of the Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et seq.) and have been assigned OMB Control Number 2120-0056.

(1) For airplanes on which the inspection is accomplished after the effective date of this AD: Submit the report within 30 days after performing the inspection.

(2) For airplanes on which the inspection was accomplished prior to the effective date of this AD: Submit the report within 30 days after the effective date of this AD.

Alternative Methods of Compliance (AMOCs)

(f)(1) In accordance with 14 CFR 39.19, the Manager, Los Angeles Aircraft Certification Office (ACO), FAA, is authorized to approve AMOCs for this AD.

(2) Before using any AMOC approved in accordance with § 39.19 on any airplane to which the AMOC applies, notify the appropriate principal inspector in the FAA Flight Standards Certificate Holding District Office.

(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 Commercial Airplanes Delegation Option Authorization Organization who has been authorized by the Manager, Los Angeles ACO, to make those findings. For a repair method to be approved, the repair must meet the certification basis of the airplane and 14 CFR 25.571, Amendment 45, and the approval must specifically refer to this AD.

Issued in Renton, Washington, on July 18, 2006.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.