[Federal Register Volume 65, Number 105 (Wednesday, May 31, 2000)]
[Proposed Rules]
[Pages 34604-34606]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-13568]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-206-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 747-100, -200, -300, -400, 
and 747SR Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Supplemental notice of proposed rulemaking; reopening of 
comment period.

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SUMMARY: This document revises an earlier proposed airworthiness 
directive (AD), applicable to certain Boeing Model 747 series 
airplanes, that would have required a one-time inspection to determine 
whether H-11 steel bolts are installed as attach and support bolts at 
the trailing edge flap transmissions, and replacement of any H-11 steel 
bolt with an Inconel bolt. That proposal was prompted by reports of 
fracturing or cracking of H-11 steel bolts at the flap transmissions. 
This new action revises the proposed rule by expanding the 
applicability to include additional airplanes. The actions specified by 
this new proposed AD are intended to prevent loss of a flap 
transmission, which could reduce lateral controllability of the 
airplane.

DATES: Comments must be received by July 5, 2000.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 99-NM-206-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056. Comments may be inspected at this 
location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except 
Federal holidays.
    The service information referenced in the proposed rule may be 
obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, 
Washington 98124-2207. This information may be examined at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington.

FOR FURTHER INFORMATION CONTACT: Barbara Mudrovich, Aerospace Engineer, 
Systems and Equipment Branch, ANM-130S, FAA, Transport Airplane 
Directorate, Seattle Aircraft Certification Office, 1601 Lind Avenue, 
SW., Renton, Washington 98055-4056; telephone (425) 227-2983; fax (425) 
227-1181.

SUPPLEMENTARY INFORMATION:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed rule by submitting such written data, views, or arguments as 
they may desire. Communications shall identify the Rules Docket number 
and be submitted in triplicate to the address specified above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule.
    The proposals contained in this notice may be changed in light of 
the comments received.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the proposed rule. All 
comments submitted will be available, both before and after the closing 
date for comments, in the Rules Docket for examination by interested 
persons. A report summarizing each FAA-public contact concerned with 
the substance of this proposal will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 99-NM-206-AD.'' The postcard will be date stamped and 
returned to the commenter.

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules 
Docket No. 99-NM-206-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    A proposal to amend part 39 of the Federal Aviation Regulations (14 
CFR part 39) to add an airworthiness directive (AD), applicable to 
certain Boeing Model 747 series airplanes, was published as a notice of 
proposed rulemaking (NPRM) in the Federal Register on December 28, 1999 
(64 FR 72582). That NPRM would have required a one-time inspection to 
determine whether H-11 steel bolts are installed as attach and support 
bolts at the trailing edge flap transmissions, and replacement of any 
H-11 steel bolt with an Inconel bolt. That NPRM was prompted by reports 
of fracturing or cracking of H-11 steel bolts at the flap 
transmissions. That condition, if not corrected, could result in loss 
of a flap transmission, which could reduce lateral controllability of 
the airplane.

Comments

    Due consideration has been given to the comments received in 
response to the NPRM. Certain comments have resulted in changes to the 
NPRM.

Request To Expand Applicability

    One commenter, an operator, requests that the FAA expand the 
applicability of the proposed rule to include all Model 747 series 
airplanes. The commenter points out that, though only Model 747 series 
airplanes having line numbers 1 through 871 inclusive were delivered 
with the affected bolts, the affected bolts may have been installed as 
spares on Model 747 series airplanes after line number 871. The 
commenter states that it found the subject bolts installed on airplanes 
in its fleet that are not included in the applicability of the proposed 
rule. The FAA concurs with the commenter's request and has revised the 
applicability statement of this supplemental NPRM to include all Model 
747-100, -100B, -100B SUD, -200B, -200C, -200F, -300, -400, -400D, -
400F, and 747SR series airplanes.

Request To Revise ``Cost Impact'' Section

    Several commenters request that the FAA revise the cost impact 
information provided in the preamble of the NPRM. One commenter states 
that the cost information in the NPRM is not consistent with the 
service bulletin, and requests that the cost impact information be 
revised to reflect the estimates in the service bulletin. Another 
commenter states that it does not understand the estimate of 6 work 
hours per airplane and estimates a total of 24 work hours will be 
necessary to accomplish both the inspection and

[[Page 34605]]

replacement described in the NPRM. The same commenter further states, 
``The NPRM cost estimate does not include replacement costs nor does it 
even include the access costs required for the inspection. This is not 
industry-accepted practice.''
    The FAA partially concurs with the commenters' request. The cost 
impact information in AD rulemaking actions describes only the 
``direct'' costs of the specific actions required by this AD. The FAA 
recognizes that, in accomplishing the requirements of any AD, operators 
may incur ``incidental'' costs in addition to the ``direct'' costs. The 
cost analysis in AD rulemaking actions, however, typically does not 
include incidental costs, such as the time required to gain access and 
close up, planning time, or time necessitated by other administrative 
actions. Because incidental costs may vary significantly from operator 
to operator, they are almost impossible to calculate.
    The estimate of 6 work hours in the NPRM is based on the figures in 
the service bulletin of 0.25 work hour for inspection and 0.50 work 
hour for replacement of bolts, for a total of 0.75 hour per 
transmission, and 6.0 work hours per airplane. However, based on the 
comments received, the FAA finds that clarification of the breakdown of 
the costs associated with the proposed AD is necessary. Therefore, the 
FAA has revised the cost impact information in this supplemental NPRM 
to separate the cost estimates for inspection and bolt replacement (if 
necessary). In addition, the estimated parts cost has been included.

Request To Revise Language in ``Discussion'' Section

    One commenter, the manufacturer, requests that the FAA revise 
certain language in the ``Discussion'' section of the NPRM. The subject 
sentence reads, ``Broken bolts could lead to loss of a flap 
transmission, which could result in flap asymmetry, flap skew, or 
collateral system damage.'' The commenter requests that the sentence be 
revised to read, ``* * * flap skew, and/or collateral system damage.'' 
The commenter states, ``* * * in addition to the flap skew or 
asymmetry, a reduction in flight control system capability is also 
possible due to potential adjacent systems damage (e.g., hydraulic 
lines, cables, wiring, etc.).''
    The FAA concurs with the intent of the commenter's request. 
However, the ``Discussion'' section is not restated in this 
supplemental NPRM; therefore, no change is necessary in this regard.

Conclusion

    Since these changes expand the scope of the originally proposed 
rule, the FAA has determined that it is necessary to reopen the comment 
period to provide additional opportunity for public comment.

Cost Impact

    There are approximately 1,240 airplanes of the affected design in 
the worldwide fleet. The FAA estimates that 281 airplanes of U.S. 
registry would be affected by this proposed AD.
    It would take approximately 2 work hours per airplane to accomplish 
the proposed inspection, at an average labor rate of $60 per work hour. 
Based on these figures, the cost impact of the inspection proposed by 
this AD on U.S. operators is estimated to be $33,720, or $120 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.
    Should an operator be required to accomplish the bolt replacement, 
it will take approximately 4 work hours per airplane (0.5 hours per 
transmission) to accomplish, at an average labor rate of $60 per work 
hour. Required parts will cost approximately $5,049 per airplane. Based 
on these figures, the cost impact of the replacement is estimated to be 
$5,289 per airplane.

Regulatory Impact

    The regulations proposed herein 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. Therefore, it 
is determined that this proposal would not have federalism implications 
under Executive Order 13132.
    For the reasons discussed above, I certify that this 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) if promulgated, 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 copy of the draft 
regulatory evaluation prepared for this action is contained in the 
Rules Docket. A copy of it may be obtained by contacting the Rules 
Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 
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:

Boeing: Docket 99-NM-206-AD.

    Applicability: All Model 747-100, -100B, -100B SUD, -200B, -
200C, -200F, -300, -400, -400D, -400F, and 747SR series 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 (b) 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 loss of a flap transmission, which could reduce 
lateral controllability of the airplane, accomplish the following:

Replacement

    (a) Within 1 year after the effective date of this AD, perform a 
one-time general visual inspection to determine whether H-11 steel 
bolts are installed as attach and support bolts at the trailing edge 
flap transmissions, in accordance with Boeing Alert Service Bulletin 
747-27A2376, dated July 1, 1999.
    (1) If no H-11 steel bolt is found, no further action is 
required by this AD.
    (2) If any H-11 steel bolt is found, prior to further flight, 
replace with an Inconel bolt, in accordance with the alert service 
bulletin.

    Note 2: For the purposes of this AD, a general visual inspection 
is defined as: ``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 under normally 
available lighting conditions such as daylight, hangar lighting, 
flashlight, or drop-light, and may require removal or opening of

[[Page 34606]]

access panels or doors. Stands, ladders, or platforms may be 
required to gain proximity to the area being checked.''

Alternative Methods of Compliance

    (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.

    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

    (c) 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.

    Issued in Renton, Washington, on May 24, 2000.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 00-13568 Filed 5-30-00; 8:45 am]
BILLING CODE 4910-13-P