[Federal Register Volume 61, Number 177 (Wednesday, September 11, 1996)]
[Rules and Regulations]
[Pages 47804-47806]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-22918]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 95-NM-212-AD; Amendment 39-9751; AD 96-19-03]
RIN 2120-AA64


Airworthiness Directives; McDonnell Douglas Model DC-10 and MD-11 
Series Airplanes and KC-10A (Military) Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to all McDonnell Douglas Model DC-10 and MD-11 series 
airplanes and KC-10A (military) airplanes, that requires repetitive 
inspections to detect corrosion or failure of the steel Hi-Lok 
fasteners at the inboard flap inboard track, and replacement of 
corroded/failed steel Hi-Lok fasteners with inconel Hi-Lok fasteners. 
This amendment also provides for termination of the repetitive 
inspections by replacing all of the steel Hi-Lok fasteners with inconel 
Hi-Lok fasteners. This amendment is prompted by reports of failed and/
or corroded steel fasteners found in the inboard flap inboard track due 
to stress corrosion. The actions specified by this AD are intended to 
prevent such stress corrosion, which could result in binding of the 
flap and inability of the flap to extend or retract; this situation may 
lead to asymmetric flap deployment and subsequent reduced 
controllability of the airplane during flight.

DATES: Effective October 16, 1996.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of October 16, 1996.

ADDRESSES: The service information referenced in this AD may be 
obtained from McDonnell Douglas Corporation, 3855 Lakewood Boulevard, 
Long Beach, California 90846, Attention: Technical Publications 
Business Administration, Department 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, Los Angeles Aircraft Certification Office, 
Transport Airplane Directorate, 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: Ron Atmur, Aerospace Engineer, 
Airframe Branch, ANM-120L, FAA, Los Angeles Aircraft Certification 
Office, 3960 Paramount Boulevard, Lakewood, California 90712; telephone 
(310) 627-5224; fax (310) 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 all McDonnell Douglas Model DC-10 
and MD-11 series airplanes and KC-10A (military) airplanes was 
published in the Federal Register on April 19, 1996 (61 FR 17261). That 
action proposed to require repetitive visual inspections to detect 
corrosion or failure of the steel Hi-Lok fasteners at the inboard flap 
inboard track. That action also proposed to require replacement of 
corroded/failed steel Hi-Lok fasteners with inconel Hi-Lok fasteners. 
In addition, that action proposed to provide for an optional 
terminating action for the repetitive inspection requirements by 
replacing all the steel Hi-Lok fasteners with Hi-Lok fasteners made of 
inconel.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comments received.

Support for the Proposal

    One commenter supports the proposed rule.

Request To Allow Installation of Steel Hi-Lok Fasteners

    One commenter requests that the proposal be revised to allow the 
replacement of corroded or damaged steel fasteners with the same part-
numbered steel Hi-Lok fasteners, instead of inconel Hi-Lok fasteners. 
This commenter raises concerns about the timely availability of 
replacement fasteners. The commenter points out that procuring inconel 
Hi-Lok fasteners may entail a lead time of several months, but steel 
Hi-Lok fasteners are readily available. Mandating the use of only 
inconel fasteners as replacement parts could result in many aircraft 
being grounded unnecessarily due to the unavailability of parts.
    The FAA concurs with this commenter's request. The FAA finds that 
an acceptable level of safety will be maintained if failed or corroded 
steel Hi-Lok fasteners are replaced with like steel fasteners and 
repetitively inspected. (Additionally, the McDonnell Douglas service 
bulletins referenced in the AD contain a statement indicating: ``If 
inconel Hi-Loks are unavailable, operators may use same material steel 
Hi-Loks as removed.'') This finding, however, does not affect the 
terminating action provided in this AD, which, if accomplished, 
requires the replacement of all fasteners with ones made of inconel.
    Paragraphs (a)(2)(i) and (b)(2)(i) of the final rule have been 
revised to allow fasteners to be replaced with either steel or inconel 
Hi-Lok fasteners (and

[[Page 47805]]

repetitively inspected until terminating action is accomplished).

Request To Extend Initial Compliance Time for Model MD-11's

    One commenter requests that paragraph (b) of the proposal be 
revised to extend the compliance time for the initial inspection of 
Model MD-11 series airplanes from the proposed 18 months to 72 months. 
As justification for this request, the commenter points out that there 
have been no reports of failed fasteners on any Model MD-11 airplane; 
the only reports of failures have occurred on Model DC-10 series 
airplanes that had accumulated more than 18,000 total flight cycles. In 
light of this record, the commenter considers an 18-month compliance 
time unwarranted for the Model MD-11.
    The FAA does not concur with the commenter's request. The flap 
inboard tracks of both the Model MD-11 and Model DC-10 series airplanes 
are similar in design; they also operate at similar stresses and in 
similar environments. In light of this, the flaps of the Model MD-11 
may experience the same corrosion problems as the Model DC-10 airplanes 
have experienced. Additionally, stress corrosion is unpredictable; 
neither the FAA nor McDonnell Douglas can predict the onset of this 
phenomenon. Therefore, the FAA has determined that it is necessary to 
begin inspections as early as is reasonably possible.
    In developing an appropriate compliance time for the inspections, 
the FAA considered not only the degree of urgency associated with 
addressing the subject unsafe condition, but the availability of 
required parts and the practical aspect of inspecting the fleet at 
intervals of time that closely parallel normally scheduled maintenance 
for the majority of affected operators. In consideration of all of 
these factors, the FAA has determined that the compliance time, as 
proposed, is not only appropriate, but warranted.

Conclusion

    After careful review of the available data, including the comments 
noted above, the FAA has determined that air safety and the public 
interest require the adoption of the rule with the changes previously 
described. The FAA has determined that these changes will neither 
increase the economic burden on any operator nor increase the scope of 
the AD.

Cost Impact

    The FAA estimates that 276 airplanes of U.S. registry will be 
affected by this AD, that it will take approximately 2 work hours per 
airplane to accomplish the required actions, 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 $33,120, or $120 per 
airplane, per inspection cycle.
    The cost impact figure discussed above is based on assumptions that 
no operator has yet accomplished any of the 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 substantial direct 
effects 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, in 
accordance with Executive Order 12612, it is determined that this final 
rule does not have sufficient federalism implications to warrant the 
preparation of a Federalism Assessment.
    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.


Sec. 39.13  [Amended]

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

96-19-03  McDonnell Douglas: Amendment 39-9751. Docket 95-NM-212-AD.

    Applicability: All Model DC-10 and MD-11 series airplanes, and 
KC-10A (military) 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 (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 in the fasteners in the 
inboard flap inboard track, which could result in binding of the 
flap and inability of the flap to extend or retract, accomplish the 
following:
    (a) For Model DC-10 series airplanes and KC-10A (military) 
airplanes: Within 18 months after the effective date of this AD, 
perform a visual inspection to detect corrosion or failure of the 
steel Hi-Lok fasteners at the inboard flap inboard track in 
accordance with McDonnell Douglas Service Bulletin DC-10-57-134, 
dated August 15, 1995.
    (1) If no corrosion or failure is detected, accomplish either 
paragraph (a)(1)(i) or (a)(1)(ii) of this AD.
    (i) Repeat the inspection required by paragraph (a) of this AD 
thereafter at intervals not to exceed 18 months until paragraph 
(a)(1)(ii) of this AD is accomplished.
    (ii) Replace all steel Hi-Lok fasteners with inconel Hi-Lok 
fasteners in accordance with McDonnell Douglas Service Bulletin DC-
10-57-134, dated August 15, 1995. Accomplishment of this replacement 
constitutes terminating action for the repetitive inspection 
requirements of paragraph (a)(1)(i) of this AD.
    (2) If any corrosion or failure is detected, prior to further 
flight, accomplish either paragraph (a)(2)(i) or (a)(2)(ii) of this 
AD, in accordance with McDonnell Douglas Service Bulletin DC-10-57-
134, dated August 15, 1995.
    (i) Replace all corroded/failed steel Hi-Lok fasteners with 
either like steel Hi-Lok fasteners or inconel Hi-Lok fasteners, in 
accordance with the service bulletin. Thereafter, repeat the visual 
inspection required by paragraph (a) of this AD at intervals not to 
exceed 18 months until paragraph (a)(2)(ii) of this AD is 
accomplished.
    (ii) Replace all steel Hi-Lok fasteners with inconel Hi-Lok 
fasteners, in accordance with

[[Page 47806]]

McDonnell Douglas Service Bulletin DC-10-57-134, dated August 15, 
1995. Accomplishment of this replacement constitutes terminating 
action for the repetitive inspection requirements of paragraph 
(a)(2)(i) of this AD.
    (b) For Model MD-11 series airplanes: Within 18 months after the 
effective date of this AD, perform a visual inspection to detect 
corrosion or failures of the steel Hi-Lok fasteners at the inboard 
flap inboard track in accordance with McDonnell Douglas Service 
Bulletin MD11-57-031, dated August 15, 1995.
    (1) If no corrosion or failures are detected, accomplish either 
paragraph (b)(1)(i) or (b)(2)(ii) of this AD.
    (i) Repeat the inspection required by paragraph (b) of this AD 
thereafter at intervals not to exceed 18 months until paragraph 
(b)(1)(ii) of this AD is accomplished.
    (ii) Replace all steel Hi-Lok fasteners with inconel Hi-Lok 
fasteners in accordance with McDonnell Douglas Service Bulletin 
MD11-57-031, dated August 15, 1995. Accomplishment of this 
replacement constitutes terminating action for the repetitive 
inspection requirements of paragraph (b)(1)(i) of this AD.
    (2) If any corrosion or failure is detected during the 
inspection required by paragraph (b) of this AD, prior to further 
flight, accomplish either paragraph (b)(2)(i) or (b)(2)(ii) of this 
AD, in accordance with McDonnell Douglas Service Bulletin MD11-57-
031, dated August 15, 1995.
    (i) Replace all corroded/failed steel Hi-Lok fasteners with 
either like steel Hi-Lok fasteners or inconel Hi-Lok fasteners, in 
accordance with the service bulletin. Thereafter, repeat the visual 
inspection required by paragraph (b) of this AD at intervals not to 
exceed 18 months until paragraph (b)(2)(ii) of this AD is 
accomplished.
    (ii) Replace all steel Hi-Lok fasteners with inconel Hi-Lok 
fasteners in accordance with McDonnell Douglas Service Bulletin 
MD11-57-031, dated August 15, 1995. Accomplishment of this 
replacement constitutes terminating action for the repetitive 
inspection requirements of paragraph (b)(2)(i) of this AD.
    (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.

    (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.
    (e) The inspections and replacement shall be done in accordance 
with McDonnell Douglas Service Bulletin DC-10-57-134, dated August 
15, 1995 (for Model DC-10 series airplanes); and McDonnell Douglas 
Service Bulletin MD11-57-031, dated August 15, 1995 (for Model MD-11 
series airplanes). 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 McDonnell 
Douglas Corporation, 3855 Lakewood Boulevard, Long Beach, California 
90846, Attention: Technical Publications Business Administration, 
Department C1-L51 (2-60). Copies may be inspected at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington; or at the FAA, Los Angeles Aircraft Certification 
Office, Transport Airplane Directorate, 3960 Paramount Boulevard, 
Lakewood, California; or at the Office of the Federal Register, 800 
North Capitol Street, NW., suite 700, Washington, DC.
    (f) This amendment becomes effective on October 16, 1996.

    Issued in Renton, Washington, on September 3, 1996.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 96-22918 Filed 9-10-96; 8:45 am]
BILLING CODE 4910-13-U