[Federal Register Volume 59, Number 55 (Tuesday, March 22, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-4276]


[[Page Unknown]]

[Federal Register: March 22, 1994]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 93-NM-73-AD; Amendment 39-8842, AD 94-05-04]

 

Airworthiness Directives; Boeing Model 727 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to certain Boeing Model 727 series airplanes, that requires 
incorporation of certain structural modifications. This amendment is 
prompted by an evaluation by the Model 727 Structures Working Group, 
comprised of aircraft operators, manufacturers, and the FAA. This 
Working Group evaluated Boeing service bulletins that must be included 
as part of the ``Aging Airplane Structural Modification Program.'' The 
actions specified by this AD are intended to prevent degradation in the 
structural capabilities of the affected airplanes. The actions also 
reflect the FAA's decision that long term continued operational safety 
should be assured by actual modification of the airframe rather than 
repetitive inspections.
DATES: Effective April 21, 1994.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of April 21, 1994.

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: Walter Sippel, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Transport Airplane Directorate, Seattle 
Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056; telephone (206) 227-2774; fax (206) 227-1181.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations to include an airworthiness directive (AD) that is 
applicable to certain Boeing Model 727 series airplanes was published 
in the Federal Register on August 31, 1993 (58 FR 45861). That action 
proposed to require incorporation of certain structural modifications.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comments received.
    One commenter supports the proposed rule.
    One commenter requests that the FAA issue one rulemaking action 
that would combine the requirements of this proposal, which proposes to 
require the modifications listed in Boeing Document Number D6-54860, 
``Aging Airplane Service Bulletin Structural Modification and 
Inspection Program--Model 727,'' Revision G, dated March 5, 1993, with 
the proposal to require the inspections listed in that Boeing Document. 
That rulemaking action was proposed in AD Docket 93-NM-72-AD (58 FR 
45863, August 31, 1993). This commenter requests that these two 
rulemaking actions be combined with AD 90-06-09, Amendment 39-6488 (55 
FR 8370, March 7, 1990), which references Revision C, of Boeing 
Document Number D6-54860, dated December 11, 1989, for purposes of 
easing operators' tracking compliance with these three separate 
rulemaking actions. The FAA does not concur. The FAA's normal policy in 
this regard is that when an AD requires a substantive change, such as a 
change in the existing AD's requirements, the existing AD (AD 90-06-09) 
is superseded by being removed from the system and a new AD added. 
However, to supersede the existing AD and replace it with a new one 
having a new AD number, would serve no purpose in terms of the ability 
of affected operators to track compliance with the AD and maintain 
accurate records of compliance. In consideration of the consequent 
workload associated with revising maintenance records to enter new AD 
numbers to demonstrate compliance with requirements accomplished 
previously, the FAA has determined that a less burdensome approach is 
to issue a separate AD. This final rule is issued as a separate AD 
action since combining these rulemaking actions would necessitate 
recordkeeping changes to reflect new AD numbers. The FAA does not 
intend to supersede or revise AD 90-06-09. As such, the modifications 
required by this AD do not supersede the requirements of AD 90-06-09; 
operators must continue to comply with the requirements of that AD. 
Furthermore, the FAA's intent in keeping the requirement to accomplish 
the inspections listed in the Boeing Document separated from the 
requirement to accomplishment the modifications listed in the Boeing 
Document was to minimize the recordkeeping burden to the operators; 
i.e., operators will not be required to make recordkeeping changes to 
their inspection entries whenever revisions are made to modification 
requirements and vice versa.
    Several commenters request that proposed paragraph (a) be revised 
to clarify that only the structural modifications listed in Appendices 
A.3, B.3, and C.3 of the Boeing Document must be accomplished. Since 
the proposal stated that the modifications were listed in ``Section 3 
and Appendices A., B., and C.,'' of the Boeing Document, these 
commenters contend that the possibility exists for misinterpretation. 
Section 3 of the Boeing Document lists structural modifications that 
are required by AD 90-06-09 and Appendices A. and B. list structural 
inspections that are included in AD Docket 93-NM-72-AD (58 FR 45863, 
August 31, 1993), which proposes to require structural inspections of 
older airplanes. The FAA concurs. The FAA finds that these commenters' 
suggestion to reference the specific appendices of the Boeing Document 
(rather than the generalization cited in the proposal) would avoid any 
possibility for misinterpretation. Therefore, paragraph (a) of the 
final rule has been revised accordingly.
    One commenter requests that the proposal be revised to permit 
deviations to the modifications required by proposed paragraph (a) to 
be accomplished in accordance with FAA-approved data, e.g., Structural 
Repair Manuals; FAA Form 8110-3, Statement of Compliance with the 
Federal Aviation Regulations; etc. The commenter's intent for 
requesting this change is to gain authorization to make minor 
deviations, such as oversizing fasteners and substituting materials, 
without obtaining approval for an alternative method of compliance for 
each deviation. The FAA does not concur. The FAA has determined that 
the Manager, Seattle Aircraft Certification Office, must approve any 
such deviations to the AD's requirements. Given that possible new 
relevant issues might be revealed during this process, it is imperative 
that the FAA, at this level, have such feedback. Only by reviewing 
deviation approvals can the FAA be assured of this feedback and of the 
adequacy of the repair methods. However, when the FAA has obtained an 
adequate sampling of the quality, type, and extent of repairs being 
made as a result of this AD, the FAA anticipates that it will, at some 
future date, authorize manufacturer's Designated Engineering 
Representatives to approve minor deviations to the modifications 
required by this final rule, as it has done in the past regarding the 
requirements of AD 90-06-09, and other aging fleet AD's.
    One commenter noted that the economic impact information in the 
proposal reflects an extremely low estimate ($55 per work hour) of the 
labor rate incurred by industry. This commenter stated that a more 
realistic labor rate would be in the range of $60 to $100 per work 
hour. From this comment, the FAA infers that the commenter is 
requesting that the economic impact information be revised and computed 
using a higher labor rate figure. The FAA does not concur. The figure 
of $55 per work hour used in the economic impact information, below, 
was based upon data provided to the FAA by various operators in 
industry. As such, the FAA uses this figure based upon the best data 
available to date.
    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 change previously 
described. The FAA has determined that this change will neither 
increase the economic burden on any operator nor increase the scope of 
the AD.
    There are approximately 1,635 Model 727 series airplanes of the 
affected design in the worldwide fleet. The FAA estimates that 70 
airplanes of U.S. registry will be affected by this AD within the 
initial threshold of 4 years. The cost to modify each airplane is 
estimated to be $260,155. This cost includes the price of modification 
kits, which is $186,180 per airplane, and the estimated number of work 
hours to accomplish the modifications, which is 1,345 work hours at $55 
per work hour. It does not include downtime, planning, set up, 
familiarization, or tool acquisition costs. Based on these figures, the 
total cost impact of the AD on U.S. operators is estimated to be 
$18,210,850 over the 4-year time period.
    The total 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.
    The FAA recognizes that the obligation to maintain aircraft in an 
airworthy condition is vital, but sometimes expensive. Because AD's 
require specific actions to address specific unsafe conditions, they 
appear to impose costs that would not otherwise be borne by operators. 
However, because of the general obligation of operators to maintain 
aircraft in an airworthy condition, this appearance is deceptive. 
Attributing those costs solely to the issuance of this AD is 
unrealistic because, in the interest of maintaining safe aircraft, most 
prudent operators would accomplish the required actions even if they 
were not required to do so by the AD.
    A full cost-benefit analysis has not been accomplished for this AD. 
As a matter of law, in order to be airworthy, an aircraft must conform 
to its type design and be in a condition for safe operation. The type 
design is approved only after the FAA makes a determination that it 
complies with all applicable airworthiness requirements. In adopting 
and maintaining those requirements, the FAA has already made the 
determination that they establish a level of safety that is cost-
beneficial. When the FAA, as in this AD, makes a finding of an unsafe 
condition, this means that this cost-beneficial level of safety is no 
longer being achieved and that the required actions are necessary to 
restore that level of safety. Because this level of safety has already 
been determined to be cost-beneficial, a full cost-benefit analysis for 
this AD would be redundant and unnecessary.
    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 14 CFR part 
39 of the Federal Aviation Regulations as follows:
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PART 39--AIRWORTHINESS DIRECTIVES

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

    Authority: 49 U.S.C. App. 1354(a), 1421 and 1423; 49 U.S.C. 
106(g); and 14 CFR 11.89.


Sec. 39.13  [Amended]

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

94-05-04 Boeing: Amendment 39-8842. Docket 93-NM-73-AD.

    Applicability: Model 727 series airplanes, as listed in Boeing 
Document D6-54860, ``Aging Airplane Service Bulletin Structural 
Modification and Inspection Program--Model 727,'' Revision G, dated 
March 5, 1993; certificated in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent structural failure, accomplish the following:
    (a) Prior to reaching the incorporation thresholds listed in 
Boeing Document Number D6-54860, ``Aging Airplane Service Bulletin 
Structural Modification and Inspection Program--Model 727,'' 
Revision G, dated March 5, 1993, or within the next 4 years after 
the effective date of this AD, whichever occurs later, accomplish 
the structural modifications listed in Appendices A.3, B.3, and C.3 
of the Boeing Document.

    Note 1: The modifications required by this paragraph do not 
terminate the inspection requirements of any other AD unless that AD 
specifies that any such modification constitutes terminating action 
for the inspection requirements.

    (b) 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 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, Seattle ACO.
    (c) Special flight permits may be issued in accordance with 
Federal Aviation Regulations (FAR) 21.197 and 21.199 to operate the 
airplane to a location where the requirements of this AD can be 
accomplished.
    (d) The modifications shall be done in accordance with Boeing 
Document Number D6-54860, ``Aging Airplane Service Bulletin 
Structural Modification and Inspection Program--Model 727,'' 
Revision G, dated March 5, 1993, which contains the following list 
of effective pages: 

------------------------------------------------------------------------
                              Revision sym                              
          Page No.              shown on         Date shown on page     
                                  page                                  
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List of active pages, pages   G             (These pages are not dated.)
 c.1 and c.2.                                                           
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    ---Note: The issue date of this document is indicated only on 
page d.7; no other page of the document is dated.

    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.
    (e) This amendment becomes effective on April 21, 1994.

    Issued in Renton, Washington, on February 18, 1994.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 94-4276 Filed 3-21-94; 8:45 am]
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