[Federal Register Volume 65, Number 82 (Thursday, April 27, 2000)]
[Rules and Regulations]
[Pages 24631-24635]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-10161]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-56-AD; Amendment 39-11700; AD 2000-08-14]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 747 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 747 series airplanes, that requires 
repetitive inspections or checks to detect broken H-11 steel bolts at 
the wing rear spar side-of-body on the lower chord splice plate and 
kick fitting; and corrective actions, if necessary. This AD also 
requires eventual replacement of the existing bolts with new Inconel 
bolts, which constitutes terminating action for the repetitive 
inspections. This amendment is prompted by a report of broken bolts at 
the wing rear spar side-of-body on the lower chord splice plate. The 
actions specified by this AD are intended to prevent cracking of the 
bolts due to stress corrosion, which could result in reduced structural 
integrity of the wing-to-body joint structure.

DATES: Effective June 1, 2000.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of June 1, 2000.

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: Tamara L. Anderson, Aerospace 
Engineer, Airframe Branch, ANM-120S, FAA, Transport Airplane 
Directorate, Seattle Aircraft Certification Office, 1601 Lind Avenue, 
SW., Renton, Washington 98055-4056; telephone (425) 227-2771; 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 747 series 
airplanes was published in the Federal Register on September 2, 1999 
(64 FR 48120). That action proposed to require repetitive inspections 
or checks to detect broken H-11 steel bolts at the wing rear spar side-
of-body on the lower chord splice plate and kick fitting; and 
corrective actions, 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 comments received.

Request To Reference Revised Service Bulletin

    One commenter requests that the FAA revise paragraph (d) of the 
notice of proposed rulemaking (NPRM) to allow accomplishment of the 
terminating action in accordance with either the original issue of 
Boeing Alert Service Bulletin 747-57A2309, dated February 25, 1999 
(which is referenced as the appropriate source of service information 
in the NPRM), or Boeing Service Bulletin 747-57A2309, Revision 1, dated 
December 22, 1999.
    The FAA concurs with the commenter's request. Since the issuance of 
the NPRM, the FAA has reviewed and approved Boeing Service Bulletin 
747-57A2309, Revision 1. The procedures specified in that service 
bulletin are substantially similar to those in the original issue. 
Among other things, Revision 1 of the service bulletin references kits 
with cadmium-plated nuts instead of passivated nuts and revises jacking 
instructions. The FAA finds that use of either the original issue or 
Revision 1 of the service bulletin is acceptable for compliance with 
all actions specified in this AD. Therefore, the FAA is revising 
paragraphs (a), (b), and (d), of this final rule to reference Revision 
1, as well as the original issue of the service bulletin.
    In addition, no new airplanes are added to the effectivity listing 
in Revision 1 of the service bulletin, but the effectivity listing does 
show changes in airplane operators. Therefore, for clarity, the 
applicability statement of this final rule has been revised to refer to 
airplanes listed in Revision 1 instead of the original issue of the 
service bulletin.

Request To Revise Paragraph (c)

    One commenter requests that paragraph (c) of the proposed AD be 
revised to refer not only to paragraph (b), as specified in the 
proposal, but also to paragraph (d)(1). The commenter points out that 
paragraph (c) of the proposal only refers to cracks found during 
accomplishment of corrective action required by paragraph (b), but 
paragraph (d)(1) of the proposal also refers to accomplishment of 
necessary corrective actions in accordance with paragraph (c). The 
commenter recommends that paragraph (c) of this AD be revised to read 
as follows: ``If any crack is detected during any corrective action 
required by paragraph (b) of this AD or during terminating action 
required by paragraph (d)(1) of this AD. * * *'' The FAA concurs with 
the commenter's request, and has revised paragraph (c) of this final 
rule accordingly.

Request To Clarify Number of Fasteners

    One commenter requests that the FAA revise paragraphs (d)(1) and 
(d)(2) of the proposed rule to accurately state the correct number of 
fasteners for all groups of airplanes listed in the service bulletin. 
The commenter points out that airplanes in Group 2 have only four high 
strength H-11 steel bolts common to the rear spar lower chord splice 
plate, while airplanes in Groups 1, 3, 4, and 5 have eight high 
strength H-11 steel bolts common to the rear spar lower chord splice 
plate.
    The same commenter requests that the FAA revise paragraphs (d)(1) 
and (d)(2) of the proposed AD to also explicitly state that the number 
of high strength H-11 steel bolts listed in those paragraphs of the AD 
are the numbers for each side. The commenter states that this change is 
necessary for clarity.
    The FAA partially concurs with the commenter's request. The FAA 
acknowledges that airplanes in Group 2 have only four high strength H-
11 steel bolts common to the rear spar lower chord splice plate, while 
airplanes in

[[Page 24632]]

Groups 1, 3, 4, and 5 have eight high strength H-11 steel bolts common 
to the rear spar lower chord splice plate.
    However, the FAA finds that revising paragraphs (d)(1) and (d)(2) 
of this AD to refer separately to airplanes in Group 2 and airplanes in 
Groups 1, 3, 4, and 5; and to specify that the numbers given are for 
each side of the airplane; would unnecessarily complicate these 
paragraphs. Paragraph (d) of this AD states that the actions required 
by paragraphs (d)(1) and (d)(2) of this AD are to be accomplished in 
accordance with Boeing Alert Service Bulletin 747-57A2309, or Boeing 
Service Bulletin 747-57A2309, Revision 1. Boeing Service Bulletin 747-
57A2309, Revision 1, clarifies the difference in number of high 
strength H-11 steel bolts common to the rear spar lower chord splice 
plate between airplanes in Group 2 and airplanes in Groups 1, 3, 4, and 
5. The correct number of bolts is shown in Figure 1 of the service 
bulletin. In addition, the accomplishment instructions in both the 
original issue and Revision 1 of the service bulletin make it clear 
that the number of fasteners are per fitting, and fittings are 
installed on both sides of the airplane.
    In acknowledgement of the commenter's request, the FAA has revised 
paragraphs (d)(1) and (d)(2) of this final rule to delete references to 
specific numbers of bolts, and to instead refer to ``all high strength 
H-11 steel bolts common to the rear spar lower chord splice plate and 
common to the wing rear spar lower chord kick fitting.'' The FAA finds 
that no further clarification is necessary in this regard.

Request To Base Compliance Times on Accumulated Flight Hours

    One commenter requests that the FAA base compliance times for the 
proposed actions on the total number of flight hours an airplane has 
accumulated. (The FAA infers that the commenter is referring to the 
number of flight hours an airplane has accumulated as of the effective 
date of this AD.) The commenter requests one compliance time for 
airplanes with fewer than 45,000 total flight hours, and one for 
airplanes with more than 45,000 total flight hours. The commenter 
explains that, according to worldwide reports, the average number of 
flight hours for an airplane on which damage has been found is 45,000 
flight hours. The commenter does not state what compliance times it 
would consider appropriate, nor does it provide any other technical 
justification for establishing separate compliance times.
    The FAA does not concur with the commenter's request. The FAA finds 
no justification for the assumption that airplanes with fewer than 
45,000 total flight hours will have fewer broken bolts than airplanes 
with 45,000 total flight hours or more. Indeed, the FAA has determined 
that broken bolts have been found on airplanes that have accumulated 
from 10,000 to 83,704 total flight hours. No change to the final rule 
is necessary in this regard.

Request To Increase Threshold for Initial Inspection

    One commenter requests that the FAA revise paragraph (a) of the 
proposed rule to increase the threshold for the initial inspection from 
12 months to 18 months. The commenter wants the initial inspection 
threshold to be the same as the repetitive inspection interval. The 
commenter provides no technical justification for its request.
    The FAA does not concur with the commenter's request. In developing 
an appropriate compliance time for this action, the FAA considered not 
only the manufacturer's recommendation for the inspection threshold 
(one year), but also the safety implications for timely accomplishment 
of the initial inspection. In consideration of these items, the FAA has 
determined that 12 months represents an appropriate interval of time 
allowable wherein an acceptable level of safety can be maintained. No 
change to the final rule is necessary in this regard.

Request To Provide Repetitive Inspection Interval in Flight Hours

    One commenter requests that the paragraph (a) of the proposed rule 
be revised to provide a repetitive inspection interval in flight hours 
instead of calendar time (18 months). The commenter explains that 
stress corrosion cracking is related to the H-11 material of the bolt, 
and the tension loads on the lower chord when the airplane is in the 
air. The commenter does not specify what flight hour interval it 
considers appropriate.
    The FAA does not concur with the commenter's request. The 
repetitive inspection interval of 18 months is intended to make the 
inspections convenient for operators to accomplish at a regularly 
scheduled maintenance visit. No change to the final rule is necessary 
in this regard.

Request To Clarify Intent of Service Bulletin

    One commenter requests that the FAA revise paragraph (b) of the 
proposal to clarify the inspection processes intended by the service 
bulletin, and to clarify that cracked bolts, as well as broken bolts, 
must be replaced. The commenter states that paragraph (b) should read, 
``If there is any indication of cracked or broken bolts as indicated by 
cracks in the sealant, sealant separated from the bolt or structure, 
gaps under the bolt head or nut, bolt movement[,]or fuel leaks, perform 
the ultrasonic inspection or torque check in accordance with [the 
service bulletin]. If indications of a cracked or broken bolt are 
confirmed by the ultrasonic inspection or torque check, replace the 
bolt with an Inconel 718 bolt in accordance with [the service 
bulletin], prior to further flight.''
    The FAA does not concur with the commenter's request. Paragraph (a) 
of this AD requires a detailed visual inspection or an ultrasonic 
inspection or torque check to detect broken bolts. That paragraph 
specifies the inspection is to be accomplished in accordance with the 
service bulletin. As specified in Notes (a) and (b) of Figures 3, 4, 
and 5 of the service bulletin, the detailed visual inspection includes 
inspections for cracks in the sealant, sealant separated from the bolt 
or structure, gaps under the bolt head or nut, bolt movement, or fuel 
leaks. Any of these discrepancies could indicate broken bolts. 
Paragraph (b) states that if there is any indication of a broken bolt, 
the applicable corrective action must be performed in accordance with 
the service bulletin. The FAA finds that, for the purposes of this AD, 
the work instructions specified in the service bulletin are sufficient, 
and it is not necessary to repeat such instructions in the text of the 
AD. In addition, the FAA notes that cracked bolts are only expected to 
be detected by an ultrasonic inspection. If an indication of a crack is 
found during the ultrasonic inspection, the service bulletin specifies 
that the bolt must be removed. In accordance with paragraph (e) of this 
AD, this AD does not allow installation of H-11 steel bolts; therefore, 
the cracked (or broken) bolt must be replaced. The FAA finds that no 
change to the final rule is necessary in this regard.

Request To Clarify Intent of Corrective Action

    A commenter requests that the FAA revise paragraph (c) of the 
proposed rule to read, ``If any crack in the splice is detected during 
the open hole high frequency eddy current inspection during any 
corrective action required by paragraph (b) of this AD; * * *'' The 
commenter states that the inspection is intended to detect cracks in 
the fastener holes of the splice members, not cracks in the bolts.
    The FAA does not concur with the commenter's request. The FAA finds

[[Page 24633]]

that it is appropriate for paragraph (c) of this final rule to continue 
to refer to ``any crack detected during any corrective action * * *,'' 
because cracks may be detected in the splice fitting, kick fitting, 
skin, et cetera. No change to the final rule is necessary in this 
regard.

Request To Extend Compliance Time

    One commenter requests that the compliance time for the bolt 
replacement proposed in paragraph (d) of the NPRM be revised from 48 
months after the effective date of this AD to at the next ``D'' check. 
The commenter expresses concern that 48 months will not allow enough 
time to plan the bolt replacement and procure parts. Similarly, a 
second commenter (an operator) requests that the compliance time be 
extended to 72 months to coincide with that operator's ``D'' check 
interval. The commenter states that, with a compliance time of 48 
months, the proposed bolt replacement would have to be accomplished on 
several airplanes during a ``C'' check, rather than a ``D'' check. The 
commenter notes that, to accomplish the proposed terminating action, 
the fuel tanks must be purged. The commenter explains that purging the 
fuel tanks is standard procedure during a ``D'' check, but not during a 
``C'' check. The commenter states that draining the fuel tanks during a 
``C'' check will have a serious impact on the downtime for the 
maintenance visit. Also, the commenter asserts that the area subject to 
this AD was not recognized as a potential critical area in AD 89-23-07, 
amendment 39-6376 (54 FR 43801, October 27, 1989), and AD 94-07-06, 
amendment 39-8864 (59 FR 15854, April 5, 1994).
    The FAA does not concur with the commenters' request to extend the 
compliance time for accomplishment of the terminating action. In 
developing an appropriate compliance time for this action, 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 accomplishing the required actions within 
an interval of time that parallels normal scheduled maintenance for the 
majority of affected operators. The FAA finds that 48 months is an 
adequate amount of time for most operators to accomplish the 
modification at a scheduled heavy maintenance visit. Also, Revision 1 
of the service bulletin quotes a lead time of 30 weeks for obtaining 
repair kits, so the FAA does not anticipate that operators will have 
difficulty getting the required parts within the 48-month compliance 
time.
    With regard to the second commenter's remark that the area subject 
to this AD (in which H-11 steel bolts are installed) was not recognized 
as a potential critical area in other rulemaking actions, the FAA 
points out that one operator has reported four of the eight H-11 steel 
bolts broken. The manufacturer's analysis indicates that four broken 
bolts would result in the structure being unable to carry limit loads. 
The AD's that the commenter references did not take into consideration 
that multiple bolts may be broken. Additionally, the FAA notes that the 
wing rear spar side-of-body lower splice plate and kick fitting are 
primary structure. For all of these reasons, the FAA considers a 
compliance time of 48 months to be warranted for accomplishment of the 
terminating action, in that it represents an appropriate interval of 
time allowable for affected airplanes to continue to operate without 
compromising safety. No change to the final rule is necessary in this 
regard.

Request To Clarify ``Spares'' Paragraph

    One commenter requests that the FAA revise paragraph (e) of the 
NPRM to change the words ``on any airplane'' to ``on any Boeing 747 
airplane that is listed in the effectivity of [Boeing Service Bulletin] 
747-57A2309.'' The commenter states that an operator was confused about 
the meaning of the paragraph as it is phrased in the NPRM.
    The FAA does not concur with the commenter's request. The 
applicability statement of all AD actions lists all models affected by 
that AD. All of the requirements stated in an AD are applicable only to 
the airplane models listed in the applicability. The FAA finds that 
there is no justification for making the change requested by the 
commenter. 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 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

    There are approximately 523 Model 747 series airplanes of the 
affected design in the worldwide fleet. The FAA estimates that 115 
airplanes of U.S. registry will be affected by this AD.
    It will take approximately 1 work hour per airplane to accomplish 
the required inspection, at the average labor rate of $60 per work 
hour. Based on these figures, the cost impact of the inspection 
required by this AD on U.S. operators is estimated to be $6,900, or $60 
per airplane, per inspection cycle.
    It will take approximately 13 (Groups 1, 3, 4, and 5 airplanes) and 
10 (Group 2 airplanes) work hours per airplane to accomplish the open 
hole HFEC inspection and replacement, at the average labor rate of $60 
per work hour. Required parts will cost approximately $4,500 per 
airplane. Based on these figures, the cost impact of the AD on U.S. 
operators is estimated to be $5,280 (Groups 1, 3, 4, and 5 airplanes) 
and $5,100 (Group 2 airplanes) per airplane.
    The cost impact figures discussed above are 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 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:

[[Page 24634]]

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:

2000-08-14  Boeing: Amendment 39-11700. Docket 99-NM-56-AD.
    Applicability: Model 747 series airplanes, as listed in Boeing 
Service Bulletin 747-57A2309, Revision 1, dated December 22, 1999, 
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 (f) 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 cracking of the high strength H-11 steel bolts on the 
wing rear spar side-of-body on the lower chord splice plate and kick 
fitting due to stress corrosion, which could result in reduced 
structural integrity of the wing-to-body joint structure, accomplish 
the following:

Repetitive Inspections

    (a) Within 12 months after the effective date of this AD, 
perform a detailed visual inspection, or alternatively, an 
ultrasonic inspection or torque check, to detect broken H-11 steel 
bolts common to the rear spar lower chord splice plate and the H-11 
steel bolts common to the wing rear spar lower chord kick fitting, 
in accordance with Boeing Alert Service Bulletin 747-57A2309, dated 
February 25, 1999, or Boeing Service Bulletin 747-57A2309, Revision 
1, dated December 22, 1999. Thereafter, repeat the applicable 
inspection or torque check at intervals not to exceed 18 months, 
until accomplishment of the actions specified in paragraph (d) of 
this AD.

    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.''

Corrective Actions

    (b) If there is any detection or indication that any bolt is 
broken during the inspection required by paragraph (a) of this AD, 
prior to further flight, perform the applicable corrective action 
[i.e., ultrasonic inspection, torque check, high frequency eddy 
current (HFEC) inspection, repair, and replacement] in accordance 
with Boeing Alert Service Bulletin 747-57A2309, dated February 25, 
1999, or Boeing Service Bulletin 747-57A2309, Revision 1, dated 
December 22, 1999, except as provided in paragraph (c) of this AD. 
Replacement of a broken bolt with a new Inconel bolt in accordance 
with the service bulletin constitutes terminating action for the 
repetitive inspection requirements of paragraph (a) of this AD for 
that bolt only.
    (c) If any crack is detected during any corrective action 
required by paragraph (b) of this AD, or during the terminating 
action required by paragraph (d)(1) of this AD, and the service 
bulletin specifies to contact Boeing for appropriate action: Prior 
to further flight, repair in accordance with a method approved by 
the Manager, Seattle Aircraft Certification Office (ACO), FAA, 
Transport Airplane Directorate; or in accordance with data meeting 
the type certification basis of the airplane approved by a Boeing 
Company Designated Engineering Representative 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, as 
required by this paragraph, the Manager's approval letter must 
specifically reference this AD.

Terminating Action

    (d) Within 48 months after the effective date of this AD, 
accomplish the actions required by paragraphs (d)(1) and (d)(2) of 
this AD in accordance with Boeing Alert Service Bulletin 747-
57A2309, dated February 25, 1999, or Boeing Service Bulletin 747-
57A2309, Revision 1, dated December 22, 1999. Accomplishment of the 
actions specified in this paragraph constitutes terminating action 
for the repetitive inspection requirements of this AD.
    (1) Prior to accomplishing the replacement required by paragraph 
(d)(2) of this AD, perform an open hole HFEC inspection to detect 
cracks at the bolt hole location for all high strength H-11 steel 
bolts common to the rear spar lower chord splice plate and all high 
strength H-11 steel bolts common to the wing rear spar lower chord 
kick fitting. If any crack is detected, prior to further flight, 
perform applicable corrective actions in accordance with paragraph 
(c) of this AD.
    (2) Replace all high strength H-11 steel bolts common to the 
rear spar lower chord splice plate and all high strength H-11 steel 
bolts common to the wing rear spar lower chord kick fitting with new 
Inconel bolts.

Spares

    (e) As of the effective date of this AD, no person shall install 
an H-11 steel bolt having part number (P/N) BACB30MT ( ) * ( ) or 
BACB30TR ( ) * ( ), or any other H-11 steel bolt, in the locations 
specified in this AD, on any airplane.

Alternative Methods of Compliance

    (f) 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.

    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

    (g) 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

    (h) Except as provided by paragraph (c) of this AD, the actions 
shall be done in accordance with Boeing Alert Service Bulletin 747-
57A2309, including Appendix A, dated February 25, 1999, or Boeing 
Service Bulletin 747-57A2309, Revision 1, including Appendix A, 
dated December 22, 1999. 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

[[Page 24635]]

the Office of the Federal Register, 800 North Capitol Street, NW., 
suite 700, Washington, DC.
    (i) This amendment becomes effective on June 1, 2000.

    Issued in Renton, Washington, on April 18, 2000.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 00-10161 Filed 4-26-00; 8:45 am]
BILLING CODE 4910-13-U