AD 2001-09-12

[Federal Register Volume 66, Number 88 (Monday, May 7, 2001)]
[Rules and Regulations]
[Pages 22910-22913]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 01-10939]


-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-74-AD; Amendment 39-12219; AD 2001-09-12]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 727-100, -100C, and -200 
Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to certain Boeing Model 727-100, -100C, and -200 series 
airplanes, that, for certain airplanes, requires a one-time inspection 
of certain fuselage circumferential skin joints to determine the type 
of fasteners installed, and replacement of any aluminum fasteners with 
steel fasteners, if necessary; or modification of certain fuselage 
circumferential skin joints; as applicable. For certain other 
airplanes, this amendment also requires repetitive inspections to 
detect corrosion, sealant deterioration, cracking, or disbonding; 
repair, if necessary; and modification of certain fuselage 
circumferential skin joints. This amendment is prompted by reports of 
corrosion between the body skins and cold-bonded doublers at the 
fuselage circumferential skin joints. The actions specified by this AD 
are intended to prevent delamination of the cold-bonded doublers, which 
could result in corrosion of the body skins and doublers, and 
consequent reduced structural capability of the fuselage 
circumferential skin joints.

DATES: Effective June 11, 2001.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of June 11, 2001.

ADDRESSES: The service information referenced in this AD may be 
obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, 
Washington 98124-2207. 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 Office of 
the Federal Register, 800 North Capitol Street, NW., suite 700, 
Washington, DC.

FOR FURTHER INFORMATION CONTACT: Walt Sippel, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-2774; fax (425) 227-1181.

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 Boeing Model 727-100, -
100C, and -200 series airplanes was published in the Federal Register 
on December 6, 1999 (64 FR 68062). For certain airplanes, that action 
proposed to require a one-time inspection of certain fuselage 
circumferential skin joints to determine the type of fasteners 
installed, and replacement of any aluminum fasteners with steel 
fasteners, if necessary; or modification of certain fuselage 
circumferential skin joints; as applicable. For certain other 
airplanes, that action also proposed to require repetitive inspections 
to detect corrosion, sealant deterioration, cracking, or disbonding; 
repair, if necessary; and modification of certain fuselage 
circumferential skin joints.

Comments

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

Request To Delete Certain Sections of Proposed AD

    One commenter requests that Boeing Model 727 series airplanes, line 
numbers 153, 339, 416, and 540, be deleted from the applicability 
section of the proposed AD; and that paragraphs (c) and (d) of the 
proposal, which apply only to those airplanes, also be deleted. The 
commenter states that the manufacturer of those airplanes has 
determined that they cannot be repaired, and they were taken out-of-
service.
    The FAA does not concur with the commenter's request; however, the 
FAA agrees with the commenter's intent. Part 39 of the Federal Aviation 
Regulations (14 CFR part 39) states that, ``No person may operate a 
product to which an airworthiness directive applies except in 
accordance with the requirements of that airworthiness directive.'' The 
Part 39 regulation provides compliance relief for airplanes that are 
not being operated, because affected airplanes need only be in 
compliance prior to return to operation. In light of this fact, the 
airplanes having the line numbers listed above have been deleted from 
the Cost Impact paragraph, below; however, the applicability section 
and paragraphs (c) and (d) will remain in the final rule

[[Page 22911]]

should these airplanes be returned to operation.

Request To Delay or Revise Final Rule

    One commenter requests that issuance of the final rule be delayed 
until the FAA and the B-727 Working Group (Cargo Airline Association 
members) can develop a solution for the airplanes that have been 
converted from a passenger configuration to an all-cargo configuration. 
The commenter states that, if the FAA and industry are to work 
cooperatively to enhance safety, the more appropriate course of action 
would have been to place the issues addressed in the proposed rule 
before the Working Group, in lieu of issuing the proposed rule. The 
commenter notes that the FAA has worked successfully with this group in 
the past to identify and correct any cargo conversion problems.
    The FAA does not concur. To delay this action would be 
inappropriate, since the FAA has determined that an unsafe condition 
exists and that inspections must be conducted to ensure continued 
safety.
    A second commenter requests that the proposed AD be revised to 
allow for the structural benefits of the installation of the freighter 
conversion external doubler and the numerous inspections that are 
currently part of the basic airplane maintenance program, as well as 
the additional inspections required by AD 98-23-51, amendment 39-10932 
(63 FR 67771, December 9, 1998). (That AD requires inspection/
modification of fuselage skin longitudinal lap joints and is applicable 
to Model 727 series airplanes.) This revision of the proposal would be 
specific to those areas covered by the external doubler and, as such, 
would exempt converted freighters from the requirements of the proposed 
rule in the area covered by the external cargo door doubler. The 
commenter states that the report provided with its comments was used to 
obtain approval of an alternative method of compliance (AMOC) for AD 
98-23-51. The report shows that the external doubler used in the cargo 
door modification is able to carry the loads that the skin and lap 
joints currently carry, even in the event that the lap joints in that 
area were to fail. The commenter notes that these same data can be used 
for the circumferential skin joints that are the subject of this AD.
    The FAA does not concur to revise the final rule for the following 
reasons:
    1. Paragraph (a) is applicable to airplanes on which the 
modification recommended in Boeing Service Bulletin 727-53-0084, 
Revision 2, dated June 5, 1972, and the additional actions (including 
additional fastener replacement locations) specified in Boeing Document 
No. D6-54860, Revision C, dated December 11, 1989, ``Aging Airplane 
Service Bulletin Structural Modification Program--Model 727;'' or the 
modification specified in Boeing Service Bulletin 727-53-0084, Revision 
3, dated September 28, 1989; HAS been accomplished. Operators that have 
modified their airplanes in accordance with Revision 3 of the service 
bulletin may have had the steel fasteners removed and replaced with 
aluminum rivets. Paragraph (a) requires operators to inspect their 
airplanes to determine the type of fastener installed, and, if aluminum 
fasteners are found, replace them with the correct steel fasteners. The 
need to accomplish these actions is not affected by the freighter 
conversion referenced by the commenter.
    2. The actions specified in paragraph (b) of the final rule are 
essentially the same as those required by paragraph (a) of AD 90-06-09 
amendment 39-6488 (55 FR 8370, March 7, 1990). But paragraph (b) of 
this final rule requires that future modifications be accomplished in 
accordance with Revision 4 of the referenced service bulletin, which 
ensures that the correct steel fasteners will be installed. If the 
installation of the cargo conversion interferes with the ability to 
accomplish these actions, the operator should request approval of an 
AMOC, as provided by paragraph (g)(1) of this AD.
    3. The AMOC approved for AD 98-23-51 was for the longitudinal lap 
joints. The report the commenter provided supports that AMOC request 
and addresses the structural integrity of the longitudinal lap joints 
with the cargo door doubler, but it does not demonstrate that the cargo 
door doubler provides an acceptable level of safety for the 
circumferential skin joints. Based on this, the FAA finds that the 
technical data presented does not justify revising the final rule. The 
FAA will consider approval of AMOC's if the appropriate technical 
justification is submitted.
    4. Paragraphs (c), (d), and (f) of the final rule address four 
airplanes that were inadvertently omitted from the applicability 
specified in AD 90-26-09. AD 90-26-09 requires that inspections be 
accomplished, and cracks repaired, in the same areas specified in this 
AD. The FAA has reviewed its files regarding AMOC's to this AD and has 
found several that pertain to airplanes that have been converted from a 
passenger configuration to an all-cargo configuration. Because the four 
airplanes that were omitted from the applicability of AD 90-26-09 have 
not been converted to an all-cargo configuration (some have the 
original equipment manufacturer's cargo door, not an after-market 
door), there is no concern about inspecting through the doubler to the 
lower skin on those airplanes. No change to the final rule is necessary 
in this regard.

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 as proposed.

Cost Impact

    There are approximately 549 airplanes of the affected design in the 
worldwide fleet. Based on a records review, the FAA estimates that only 
374 of those airplanes are still in service. The FAA estimates that 280 
airplanes of U.S. registry still in service will be affected by this 
AD.
    The number of airplanes that will be subject to the required one-
time inspection to determine the type of fasteners installed is 
unknown. For affected airplanes, it will take approximately 45 work 
hours per airplane to accomplish the required one-time inspection, at 
an average labor rate of $60 per work hour. Based on these figures, the 
cost impact of this inspection on U.S. operators is estimated to be 
$2,700 per airplane.
    For affected airplanes, it will take approximately 192 work hours 
per airplane to accomplish the required modification of the cold-bonded 
doublers of certain fuselage circumferential skin joints, at an average 
labor rate of $60 per work hour. Required parts will cost approximately 
$1,250. Based on these figures, the cost impact of this modification on 
U.S. operators is estimated to be $12,770 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.

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.

[[Page 22912]]

    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:

2001-0912  Boeing: Amendment 39-12219. Docket 99-NM-74-AD.

    Applicability: Model 727-100, -100C, and -200 series airplanes; 
line numbers 1 through 549 inclusive; 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 (g)(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 delamination of the cold-bonded doublers, which could 
result in corrosion of the body skins and doublers, and consequent 
reduced structural capability of the fuselage circumferential skin 
joints, accomplish the following:

    Note 2: For the purposes of this AD, a detailed visual 
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.''

One-Time Inspection/Replacement

    (a) For airplanes on which the modification specified in Boeing 
Service Bulletin 727-53-0084, Revision 2, dated June 5, 1972, and 
the additional actions (including additional fastener replacement 
locations) specified in Boeing Document No. D6-54860, Revision C, 
dated December 11, 1989, ``Aging Airplane Service Bulletin 
Structural Modification Program--Model 727''; or the modification 
specified in Boeing Service Bulletin 727-53-0084, Revision 3, dated 
September 28, 1989; has been accomplished: Within 36 months after 
the effective date of this AD, perform a one-time inspection of the 
fuselage circumferential skin joints to determine the type of 
fastener installed, in accordance with Figure 7 of Boeing Service 
Bulletin 727-53-0084, Revision 4, dated August 2, 1990.
    (1) If no aluminum fasteners are found, no further action is 
required by this AD.
    (2) If any aluminum fasteners are found, prior to further 
flight, replace with steel fasteners, in accordance with Boeing 
Service Bulletin 727-53-0084, Revision 4, dated August 2, 1990.

Modification

    (b) For airplanes listed in Boeing Document No. D6-54860, 
Revision C, dated December 11, 1989, ``Aging Airplane Service 
Bulletin Structural Modification Program--Model 727'' on which the 
modification specified in Boeing Service Bulletin 727-53-0084, 
Revision 2, dated June 5, 1972, and the additional actions specified 
in Boeing Document No. D6-54860, Revision C, dated December 11, 
1989; or the modification specified in Boeing Service Bulletin 727-
53-0084, Revision 3, dated September 28, 1989; has not been 
accomplished prior to the effective date of this AD: Prior to the 
accumulation of 60,000 total flight cycles, modify the fuselage 
circumferential skin joints in accordance with Part IV of the 
Accomplishment Instructions of Boeing Service Bulletin 727-53-0084, 
Revision 4, dated August 2, 1990. Such action constitutes 
terminating action for the modification in that area required by AD 
90-06-09, amendment 39-6488.

Repetitive Inspections

    (c) For airplanes having line numbers 153, 339, 416, and 540: 
Accomplish the requirements of paragraphs (c)(1), (c)(2), and (c)(3) 
of this AD at the compliance time specified in those paragraphs.
    (1) Within 15 months after the effective date of this AD, 
perform an external detailed visual inspection and a low frequency 
eddy current (LFEC) inspection of the fuselage circumferential skin 
joints to detect corrosion or sealant deterioration, in accordance 
with Parts II.A. and II.B. of the Accomplishment Instructions of 
Boeing Service Bulletin 727-53-0084, Revision 4, dated August 2, 
1990. Repeat the external detailed visual inspection thereafter at 
intervals not to exceed 15 months, and repeat the LFEC inspection 
thereafter at intervals not to exceed 30 months.
    (2) Within 3,000 flight cycles or 30 months after the effective 
date of this AD, whichever occurs first, perform a high frequency 
eddy current (HFEC) inspection of the fuselage circumferential skin 
joints to detect cracking, in accordance with Part II.D. of the 
Accomplishment Instructions of Boeing Service Bulletin 727-53-0084, 
Revision 4, dated August 2, 1990. Repeat the HFEC inspection 
thereafter at intervals not to exceed 4,000 flight cycles or 48 
months, whichever occurs first, until accomplishment of paragraph 
(f) of this AD.
    (3) Within 48 months after the effective date of this AD, 
perform an internal detailed visual inspection of the fuselage 
circumferential skin joints to detect cracking, disbonding, or 
sealant deterioration; in accordance with Part II.C. of the 
Accomplishment Instructions of Boeing Service Bulletin 727-53-0084, 
Revision 4, dated August 2, 1990. Repeat the internal detailed 
visual inspection thereafter at intervals not to exceed 48 months.

Repair

    (d) For airplanes having line numbers 153, 339, 416, and 540: If 
any discrepancy is detected during any inspection required by 
paragraph (c) of this AD, accomplish paragraph (d)(1) or (d)(2) of 
this AD, as applicable.
    (1) If any corrosion, cracking, or disbonding is detected during 
any inspection required by paragraph (c) of this AD, prior to 
further flight, repair in accordance with Part III of the 
Accomplishment Instructions of Boeing Service Bulletin 727-53-0084, 
Revision 4, dated August 2, 1990, except as provided by paragraph 
(e) of this AD. No further action is required by this AD for that 
area.
    (2) If the sealant has deteriorated but no corrosion, cracking, 
or disbonding is detected during any inspection required by 
paragraph (c) of this AD, prior to further flight, reseal in 
accordance with Figure 5 or 6, as applicable, of Boeing Service 
Bulletin 727-53-0084, Revision 4, dated August 2, 1990.
    (e) Where the service bulletin specifies that the manufacturer 
may be contacted for disposition of certain repair conditions, prior 
to further flight, repair in accordance with a method approved by 
the Manager, Seattle Aircraft Certification Office (ACO), FAA; or in 
accordance with 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 by 
the Manager, Seattle ACO, or a Boeing DER, as required by this 
paragraph, the approval letter must specifically reference this AD.

[[Page 22913]]

Modification

    (f) For airplanes having line numbers 153, 339, 416, and 540: 
Prior to the accumulation of 60,000 total flight cycles, or within 
3,000 flight cycles after the effective date of this AD, whichever 
occurs later, modify the fuselage circumferential skin joints in 
accordance with Part IV of the Accomplishment Instructions of Boeing 
Service Bulletin 727-53-0084, Revision 4, dated August 2, 1990. Such 
action constitutes terminating action for the requirements of 
paragraph (c)(2) of this AD.

Alternative Methods of Compliance

    (g)(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 Maintenance 
Inspector, who may add comments and then send it to the Manager, 
Seattle ACO.
    (2) An alternative method of compliance for paragraph (f) of 
this AD that provides an acceptable level of safety may be used in 
accordance with 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.

    Note 3: 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

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

    (i) Except as provided by paragraph (e) of this AD, the actions 
shall be done in accordance with Boeing Service Bulletin 727-53-
0084, Revision 4, dated August 2, 1990. 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 Airplane Group, P.O. Box 3707, 
Seattle, Washington 98124-2207. Copies may be inspected at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington; or at the Office of the Federal Register, 800 North 
Capitol Street, NW., suite 700, Washington, DC.
    (j) This amendment becomes effective on June 11, 2001.

    Issued in Renton, Washington, on April 26, 2001.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 01-10939 Filed 5-4-01; 8:45 am]
BILLING CODE 4910-13-U