# AGENCY:

 Federal Aviation Administration, DOT. 

# ACTION:

 Final rule. 

# SUMMARY:

 This amendment adopts a new airworthiness directive (AD), applicable to certain McDonnell Douglas Model DC-8 series airplanes, that requires a one-time eddy current conductivity test to determine the material type of the lower cap of the wing front spar; and modification of the lower cap of the wing front spar, if necessary. This amendment is prompted by reports of stress corrosion cracking in the forward tang of the lower caps of the wing front spar. The actions specified by this AD are intended to prevent such stress corrosion cracking, which if not corrected, could result in reduced structural integrity of the wing. 

# DATES:

 Effective February 23, 2000. 

The incorporation by reference of certain publications listed in the regulations is approved by the Director of the Federal Register as of February 23, 2000. 

# ADDRESSES:

 The service information referenced in this AD may be obtained from Boeing Commercial Aircraft Group, Long Beach Division, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Technical Publications Business Administration, Dept. C1-L51 (2-60). This information may be examined at the Federal Aviation Administration (FAA), Transport Airplane Directorate, Rules Docket, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Transport Airplane Directorate, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. 

# FOR FURTHER INFORMATION CONTACT:

 Greg DiLibero, Airframe Branch, ANM-120L, FAA, Transport Airplane Directorate, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California 90712-4137; telephone (562) 627-5231; fax (562) 627-5210. 

# SUPPLEMENTARY INFORMATION:

                     A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an airworthiness directive (AD) that is applicable to certain McDonnell Douglas Model DC-8 series airplanes was published in the                     **Federal Register**                     on October 27, 1999 (64 FR 57792). That action proposed to require a one-time eddy current conductivity test to determine the material type of the lower cap of the wing front spar; and modification of the lower cap of the wing front spar, if necessary.                 

## Comments 

Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the single comment received. 

The commenter supports the proposed rule. 

## Conclusion 

After careful review of the available data, including the comment noted above, the FAA has determined that air safety and the public interest require the adoption of the rule as proposed. 

## Cost Impact 

There are approximately 294 airplanes of the affected design in the worldwide fleet. The FAA estimates that 251 airplanes of U.S. registry will be affected by this AD, that it will take approximately 3 work hours per airplane to accomplish the required inspection, and that the average labor rate is $60 per work hour. Based on these figures, the cost impact of the AD on U.S. operators is estimated to be $45,180, or $180 per airplane. 

The cost impact figure discussed above is 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. 

## Regulatory Impact 

The regulations adopted herein will 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 final rule does not have federalism implications under Executive Order 13132. 

                    For the reasons discussed above, I certify that this action: (1) Is not a “significant regulatory action” under Executive Order 12866; (2) is not a “significant rule” under 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. A final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it may be obtained from the Rules Docket at the location provided under the caption                     **ADDRESSES.**

# List of Subjects in 14 CFR Part 39

- Air transportation
- Aircraft
- Aviation safety
- Incorporation by reference
- Safety

## Adoption of the Amendment 

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends 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 

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

**2000-01-18 McDonnell Douglas:**                                 Amendment 39-11516. Docket 99-NM-21-AD.                             

*Applicability:*                                 Model DC-8 series airplanes, as listed in McDonnell Douglas Service Bulletin DC8-57-030, Revision 05, dated April 28, 1998; 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 (c) 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 stress corrosion cracking of the lower cap of the wing front spar, which if not corrected, could result in reduced structural integrity of the wing, accomplish the following: 

(a) Within 48 months after the effective date of this AD, perform a one-time eddy current conductivity test to determine the material type of the forward tang of the lower cap of the front spar in the center section of the wing, in accordance with McDonnell Douglas Service Bulletin DC8-57-030, Revision 05, dated April 28, 1998, or Revision 04, dated August 17, 1995. 

(1) If 7079-T6 aluminum is not found, no further action is required by this AD. 

(2) If any 7079-T6 aluminum is found, within 48 months after the effective date of this AD, modify the forward tang of the lower cap of the front spar, in accordance with the service bulletin. 

(b) Accomplishment of the eddy current conductivity test, and modification, if necessary, specified in paragraph (a) of this AD constitutes terminating action for the repetitive inspection requirements of paragraph (a) of AD 90-16-05, amendment 39-6614, as it applies to the inspections of the forward tang of the lower cap of the front spar specified in McDonnell Douglas Service Bulletin DC8-57-030, Revision 3, dated December 10, 1970. 

## Alternative Methods of Compliance 

(c) 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, Los Angeles Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Los Angeles ACO. 

# Note 2:

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

## Special Flight Permits 

(d) Special flight permits may be issued in accordance with 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. 

## Incorporation by Reference 

                                (e) The actions shall be done in accordance with McDonnell Douglas Service Bulletin DC8-57-030, Revision 05, dated April 28, 1998, or McDonnell Douglas Service Bulletin DC8-57-030, Revision 04, dated August 17, 1995. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Boeing Commercial Aircraft Group, Long Beach Division, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Technical Publications Business Administration, Dept. C1-L51 (2-60). Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Transport Airplane Directorate, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California; or at the                                 Start Printed Page 2864                                Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.                             

(f) This amendment becomes effective on February 23, 2000.

Issued in Renton, Washington, on January 11, 2000. 

Donald L. Riggin,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.

[FR Doc. 00-1119 Filed 1-18-00; 8:45 am] 

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