E7-22725. Airworthiness Directives; McDonnell Douglas Model DC-8-55, DC-8F-54, and DC-8F-55 Airplanes; and Model DC-8-60, DC-8-70, DC-8-60F, and DC-8-70F Series Airplanes

AGENCY:

Federal Aviation Administration (FAA), Department of Transportation (DOT).

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to supersede an existing airworthiness directive (AD) that applies to certain McDonnell Douglas Model DC-8-55, DC-8F-54, and DC-8F-55 airplanes; and Model DC-8-60, DC-8-70, DC-8-60F, and DC-8-70F series airplanes. The existing AD currently requires a one-time inspection for previous repairs of the aft fuselage skin panel at the longeron 28 skin splice; repetitive inspections for cracks of the same area; and related investigative and corrective actions. The existing AD also provides optional actions for extending the repetitive inspection intervals. This proposed AD would re-define and more clearly describe the optional actions for extending the repetitive inspection intervals. This proposed AD results from our determination that the inspections and actions described in the existing AD do not adequately address the unsafe condition. We are proposing this AD 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.

DATES:

We must receive comments on this proposed AD by January 7, 2008.

ADDRESSES:

You may send comments by any of the following methods:

• Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
• Fax: [phone].
• Mail: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590.
• Hand Delivery: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For service information identified in this AD, contact Boeing Commercial Airplanes, Long Beach Division, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Data and Service Management, Dept. C1-L5A (D800-0024).

Examining the AD Docket

You may examine the AD docket on the Internet at http://www.regulations.gov;​; or in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this proposed AD, the regulatory evaluation, any comments received, and other information. The street address for the Docket Office (telephone [phone]) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

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

We invite you to submit any relevant written data, views, or arguments regarding this proposed AD. Send your comments to an address listed in the ADDRESSES section. Include the docket number “FAA-2007-0216; Directorate Identifier 2007-NM-122-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the proposed AD. We will consider all comments received by the closing date and may amend the proposed AD in light of those comments.

We will post all comments we receive, without change, to http://www.regulations.gov,, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this proposed AD.

Discussion

On January 5, 2007, we issued AD 2007-02-02, amendment 39-14889 (72 FR 3044, January 24, 2007), for certain McDonnell Douglas Model DC-8-55, DC-8F-54, and DC-8F-55 airplanes; and Model DC-8-60, DC-8-70, DC-8-60F, and DC-8-70F series airplanes. That AD requires a one-time inspection for previous repairs of the aft fuselage skin panel at the longeron 28 skin splice; repetitive inspections for cracks of the same area; related investigative and corrective actions; and reporting inspection findings to the manufacturer. That AD also provides optional actions for extending the repetitive inspection intervals. That AD resulted from a report indicating that a crack has been found in the aft fuselage skin at the longeron 28 skin splice. We issued that AD 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.

Actions Since Existing AD Was Issued

Since we issued AD 2007-02-02, we have determined that the inspections and optional modification/repair described in that AD do not adequately address the unsafe condition. We concluded that more careful inspection of areas already repaired and reinforced by the installation of doublers was needed. Accordingly, we propose to re-define and more clearly describe certain inspections and the optional modification/repair to completely address the unsafe condition described in that AD.

FAA's Determination and Requirements of the Proposed AD

We have evaluated all pertinent information and identified an unsafe condition that is likely to develop on other airplanes of the same type design. For this reason, we are proposing this AD, which would supersede AD 2007-02-02, re-define the requirements of that AD, and clarify the optional modification/repair described in that AD which, if done, would allow extending the repetitive inspection intervals.

Changes to Existing AD

This proposed AD would re-define certain requirements and clarify the optional modification/repair of AD 2007-02-02. Since AD 2007-02-02 was issued, the AD format has been revised, and certain paragraphs have been rearranged. As a result, the corresponding paragraph identifiers have changed in this proposed AD, as listed in the following table:

Revised Paragraph Identifiers

Requirement in AD 2007-02-02	Corresponding requirement in this proposed AD
paragraph (a)	paragraph (f).
paragraph (b)	paragraph (g).
paragraph (c)	paragraph (h).

Costs of Compliance

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. The average labor rate is $80 per work hour. This proposed AD would add no additional costs; however, we are repeating the costs from AD 2007-02-02 for the convenience of affected operators.

Estimated Costs

Action	Work hours	Cost per airplane	Fleet cost
Initial Inspection for doubler installation	2 to 4	$160 to $320	$39,040 to $78,080.
Repetitive Inspections (per inspection cycle)	2 to 8	$160 to $640	$39,040 to $156,160.
Repair	164 to 184	$13,120 to $14,720	$3,201,280 to $3,591,680.

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 Findings

We have determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD 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.

For the reasons discussed above, I certify that the 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. 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.

We prepared a regulatory evaluation of the estimated costs to comply with this proposed AD and placed it in the AD docket. See the ADDRESSES section for a location to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Safety

The Proposed Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 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. The Federal Aviation Administration (FAA) amends § 39.13 by removing amendment 39-14889 (72 FR 3044, January 24, 2007) and adding the following new airworthiness directive (AD):

McDonnell Douglas: Docket No. FAA-2007-0216; Directorate Identifier 2007-NM-122-AD.

Comments Due Date

(a) The FAA must receive comments on this AD action by January 7, 2008.

Affected ADs

(b) This AD supersedes AD 2007-02-02.

Applicability

(c) This AD applies to 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.

Unsafe Condition

(d) This AD results from our determination that the inspections and actions described in the existing AD do not adequately address the unsafe condition. We are issuing this AD 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.

Compliance

(e) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.

Requirements of AD 2007-02-02

One-Time Inspection for Previous Repairs

(f) For all airplanes: At the applicable time in paragraph (f)(1) or (f)(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 specified in paragraphs (g) and (h) of this AD.

(1) For airplanes that have accumulated fewer than 24,000 total flight cycles as of February 28, 2007 (the effective date of AD 2007-02-02): Within 24 months after February 28, 2007, 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 February 28, 2007: Within 12 months after February 28, 2007.

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

(g) For areas that do not have a previous repair: Before further flight after the initial inspection in paragraph (f) of this AD, do general visual and high-frequency eddy current (HFEC) inspections for discrepancies 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 general visual and HFEC inspections thereafter at intervals not to exceed 2,000 flight cycles until an optional action in paragraph (i) of this AD is accomplished.

Repetitive Inspections and Repair for Areas That Have a Previous Repair

(h) For areas that have a previous repair: Within 24 months after accomplishing the initial inspection in paragraph (f) 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 (j) of this AD thereafter at the applicable interval specified in paragraph (j)(1) or (j)(2) of this AD.

New Requirements of This AD

Optional Modification/Repair

(i) 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 specified in paragraph (g) of this AD.

Extended Repetitive Inspection Intervals

(j) After removing the previous repair(s) and doing the actions specified in paragraph (h) of this AD or doing any optional repair or modification described in paragraph (i) of this AD: Do the actions described in paragraph (j)(1) or (j)(2) of this AD as applicable, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin DC8-53A080, dated June 22, 2004. If any discrepancy is discovered during any inspection required by this paragraph, before further flight, repair the discrepancy using a method approved in accordance with the procedures specified in paragraph (l) of this AD.

(1) For areas that have been repaired on airplanes that do have internal finger doublers installed: Within 30,000 flight cycles after doing the optional repair or modification, do a general visual inspection for discrepancies along all four external edges of the doublers. Repeat the inspection thereafter at intervals not to exceed 5,000 flight cycles.

(2) For areas that have been repaired on airplanes that do not have internal finger doublers installed: Do the actions specified in paragraph (j)(2)(i) or (j)(2)(ii) of this AD, as applicable.

(i) For any repair that is 12 inches or less along the longeron: Within 15,000 flight cycles after removing the previous repair(s) and doing the actions specified in paragraph (h) of this AD or doing any optional repair or modification specified in paragraph (i) of this AD, do a general visual inspection for discrepancies along all four external edges of the doublers. Repeat the general visual inspection thereafter at intervals not to exceed 5,000 flight cycles.

(ii) For any repair that is greater than 12 inches in length along the longeron: Within 15,000 flight cycles after removing the previous repair(s) and doing the actions specified in paragraph (h) of this AD or doing any optional repair or modification specified in paragraph (i) of this AD, do a low-frequency eddy current (LFEC) inspection for discrepancies along all four external edges of the doublers. Repeat the LFEC inspection thereafter at intervals not to exceed 10,000 flight cycles.

Reporting of Results

(k) Submit a report of positive findings of the inspections required by paragraphs (g) and (j) 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 (k)(1) or (k)(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 (44 U.S.C. 3501 et seq.) and have been assigned OMB Control Number 2120-0056.

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

(2) For any inspection 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)

(l)(1) The Manager, Los Angeles Aircraft Certification Office (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) To request a different method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. Before using any approved AMOC on any airplane to which the AMOC applies, notify your appropriate principal inspector (PI) in the FAA Flight Standards District Office (FSDO), or lacking a PI, your local FSDO.

(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.

(4) AMOCs approved previously in accordance with AD 2007-02-02, amendment 39-14889, are approved as AMOCs for the corresponding provisions of this AD.

Issued in Renton, Washington, on November 13, 2007.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.