AD Amdt-39-11245

Recurring final rule

Airworthiness Directives; Boeing Model 747-400 Series Airplanes

AD Number
Amdt-39-11245
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. 99-NM-61-AD
FR Citation
64 FR 43053
Technical illustration of a riveted aircraft structural panel and frame
Problem area Airframe structure

Applicability

TypeManufacturerModelDetails
aircraft Boeing 747-400 Airworthiness Directives; Boeing Model 747-400 Series Airplanes

Unsafe Condition

Fatigue cracking of the area surrounding the fastener holes and broken or missing fasteners on the E-42 satellite communications (SATCOM) rack and its supporting fuselage structure.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Inspect the E-42 SATCOM rack and fuselage structure for fatigue cracking and broken or missing fasteners. Perform corrective actions if necessary to repair detected issues.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Within 50 flight hours after the effective date of the AD.

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

Boeing Model 747-400 series airplanes with the E-42 satellite communications (SATCOM) rack installed.

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

This amendment adopts a new airworthiness directive (AD), applicable to certain Boeing Model 747-400 series airplanes. This action requires repetitive inspections of the E-42 satellite communications (SATCOM) rack and fuselage (supporting) structure to detect fatigue cracking of the area surrounding the fastener holes, and to detect broken or missing fasteners; and corrective actions, if necessary. This amendment is prompted by reports indicating that fatigue cracking and broken and/or missing fasteners were found on the E-42 SATCOM equipment rack structure that attaches to the fuselage structure. The actions specified in this AD are intended to detect and repair fatigue cracking of the E-42 SATCOM rack and its supporting structure, which could result in the SATCOM equipment falling from the rack, loss of SATCOM capabilities, injury to passengers, and reduced controllability of the airplane.

Document Text

Show stored source text (verify against official source)
[Federal Register Volume 64, Number 152 (Monday, August 9, 1999)]
[Rules and Regulations]
[Pages 43053-43056]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 99-20059]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-61-AD; Amendment 39-11245; AD 99-16-10]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 747-400 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to certain Boeing Model 747-400 series airplanes. This 
action requires repetitive inspections of the E-42 satellite 
communications (SATCOM) rack and fuselage (supporting) structure to 
detect fatigue cracking of the area surrounding the fastener holes, and 
to detect broken or missing fasteners; and corrective actions, if 
necessary. This amendment is prompted by reports indicating that 
fatigue cracking and broken and/or missing fasteners were found on the 
E-42 SATCOM equipment rack structure that attaches to the fuselage 
structure. The actions specified in this AD are intended to detect and 
repair fatigue cracking of the E-42 SATCOM rack and its supporting 
structure, which could result in the SATCOM equipment falling from the 
rack, loss of SATCOM capabilities, injury to passengers, and reduced 
controllability of the airplane.

DATES: Effective August 24, 1999.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of August 24, 1999.
    Comments for inclusion in the Rules Docket must be received on or 
before October 8, 1999.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 99-NM-61-AD, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056.
    The service information referenced in this AD may be obtained from 
Flight Structures Inc., 4407 172nd Street NE, Arlington, Washington 
98223. This information may be examined at the FAA, Transport Airplane 
Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, 
Transport Airplane Directorate, Los Angeles Aircraft Certification 
Office, 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: Jon Mowery, Aerospace Engineer, 
Airframe Branch, ANM-120L, FAA, Transport Airplane Directorate, Los 
Angeles Aircraft Certification Office, 3960 Paramount Boulevard, 
Lakewood, California 90712-4137; telephone (562) 627-5322; fax (562) 
627-5210.

SUPPLEMENTARY INFORMATION: The FAA has received reports indicating that 
cracking and broken and/or missing fasteners were found on the E-42 
SATCOM equipment rack structure that attaches to the fuselage structure 
on several Boeing Model 747-300 and -400 series airplanes. 
Investigation revealed that one of the four stanchions (i.e., a

[[Page 43054]]

supporting prop or brace) was found completely broken on two airplanes 
(one that had accumulated 23,693 total flight hours and the other with 
24,752 total flight hours). Further investigation revealed that the 
rigid joints of the supporting structure of the E-42 SATCOM rack, 
coupled with environmental vibration of the airplane, may have caused 
the cracking to initiate in the area surrounding the fastener holes 
(located at the rigid joints) of the supporting structure of the E-42 
SATCOM rack. The FAA also has received a report indicating that 
cracking has been detected on four freighter airplanes; one of the 
airplanes had accumulated less than 1,500 total flight hours.
    On all airplanes, the E-42 SATCOM rack hangs above the main deck 
ceiling. On freighter airplanes and ``combi'' airplanes (i.e., 
configurations with provisions for passenger seating and cargo on the 
main deck), the E-42 SATCOM rack is located near rudder and elevator 
control cables, and the SATCOM wires run above the rudder and elevator 
control cables.
    On all airplanes, failure of the rack and its supporting structure 
could result in loss of support for the E-42 SATCOM equipment, which 
could lead to chafing and arcing of the electrical wires and loss of 
SATCOM capabilities. Such failure also could result in the following 
unsafe conditions:
    <bullet> On passenger-only airplanes, the E-42 SATCOM equipment 
could break through the ceiling, which could result in injury to 
passengers.
    <bullet> On freighter and ``combi'' airplanes, the E-42 SATCOM 
equipment could fall and cause the SATCOM wires to pull and possibly 
break the rudder and/or elevator control cables, which could result in 
reduced controllability of the airplane. Failure of the SATCOM rack on 
``combi'' airplanes carrying passengers also could result in injury to 
the passengers.

Related Rulemaking

    On June 22, 1999, the FAA issued AD 99-14-04, amendment 39-11212 
(64 FR 34707, June 29, 1999), applicable to certain Boeing Model 747-
300 and -400 series airplanes, that requires repetitive inspections of 
the E-42 SATCOM rack and fuselage (supporting) structure to detect 
cracking in the area surrounding the fastener holes, and to detect 
broken and missing fasteners; and corrective actions, if necessary.

Explanation of Relevant Service Information

    The FAA has reviewed and approved Flight Structures Alert Service 
Bulletins 92FS024-53-A1, 92FS082-53-A1, and 94FS409-53-A2, all dated 
March 2, 1999, and 94FS448-53-A1, dated February 12, 1999. These alert 
service bulletins describe, among other things, procedures for a one-
time close visual inspection of the E-42 SATCOM rack and fuselage 
(supporting) structure to detect fatigue cracking of the area 
surrounding the fastener holes, and to detect broken or missing 
fasteners.

Explanation of Requirements of the Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other airplanes of the same type design, this AD is 
being issued to detect and repair fatigue cracking of the E-42 SATCOM 
rack and its supporting structure due to environmental vibration of the 
airplane. Such fatigue cracking could result in the SATCOM equipment 
falling from the rack, loss of SATCOM capabilities, injury to 
passengers, and reduced controllability of the airplane. This AD 
requires repetitive inspections of the E-42 SATCOM rack and fuselage 
(supporting) structure to detect fatigue cracking of the area 
surrounding the fastener holes, and to detect broken or missing 
fasteners; and corrective actions, if necessary. The actions are 
required to be accomplished in accordance with the applicable alert 
service bulletin described previously, except as discussed below. This 
AD also would require reporting the findings of the initial inspection 
to the FAA.

Differences Between AD and Service Information

    While the alert service bulletins do not specify that the 
inspection of the E-42 SATCOM rack and fuselage (supporting) structure 
be repeated, this AD would require repetitive inspections of the E-42 
SATCOM rack and fuselage (supporting) structure, even if fatigue 
cracking has been detected and repaired. As stated previously, the 
rigid joints of the SATCOM rack coupled with environmental vibration of 
the airplane could cause fatigue cracking to initiate in the area 
surrounding fastener holes. Furthermore, an isolated repair of an area 
and/or replacement of any fastener does not remove the unsafe condition 
for the entire E-42 SATCOM rack and fuselage (supporting) structure. In 
light of these factors, the FAA has determined that repetitive 
inspection at intervals not exceeding 3,000 flight hours, is warranted, 
and that it represents an appropriate means of addressing the unsafe 
condition while allowing affected airplanes to continue to operate 
without comprising safety.
    Operators should note that, although the alert service bulletins 
specify repair instructions for certain conditions and recommend that 
the manufacturer of the SATCOM rack be contacted for disposition of 
certain other conditions, this AD will require the repair of those 
conditions to be accomplished in accordance with a method approved by 
the FAA.

Explanation of Compliance Time

    This AD would require compliance in terms of the number of days 
after the effective date of this AD, whereas the alert service 
bulletins (previously described) recommend compliance based on the 
number of flight hours, as specified below:
    <bullet> For airplanes identified in the alert service bulletin as 
Group 1: Within 500 flight hours from receipt of alert service 
bulletin, or 12,000 flight hours since the E-42 SATCOM rack was 
installed and populated with equipment.
    <bullet> For airplanes identified in the alert service bulletin as 
Group 2: Within 1,000 flight hours from receipt of alert service 
bulletin, or 20,000 flight hours since the E-42 SATCOM rack was 
installed and populated with equipment.
    This AD would require that the initial inspection be performed at 
the applicable time, as specified below:
    <bullet> For airplanes identified in the alert service bulletin as 
Group 1: Within 30 days after the effective date of this AD.
    <bullet> For airplanes identified in the alert service bulletin as 
Group 2: Within 90 days after the effective date of this AD.
    The FAA finds that, in view of a recent report indicating that 
cracking has been detected on an airplane that had accumulated less 
than 1,500 total flight hours, and because of the safety implications 
and consequences associated with such cracking, the initial compliance 
time specified in this AD is appropriate.

Interim Action

    This is considered to be interim action. The manufacturer has 
advised that it currently is developing a modification that will 
positively address the unsafe condition addressed by this AD. Once this 
modification is developed, approved, and available, the FAA may 
consider additional rulemaking.

Cost Impact

    None of the Model 747-400 series airplanes affected by this action 
are on the U.S. Register. All airplanes included in the applicability 
of this rule currently are operated by non-U.S. operators under foreign 
registry; therefore, they

[[Page 43055]]

are not directly affected by this AD action. However, the FAA considers 
that this rule is necessary to ensure that the unsafe condition is 
addressed in the event that any of these subject airplanes are imported 
and placed on the U.S. Register in the future.
    Should an affected airplane be imported and placed on the U.S. 
Register in the future, it would require approximately 3 work hours to 
accomplish the required inspection, at an average labor rate of $60 per 
work hour. Based on these figures, the cost impact of this AD would be 
$180 per airplane, per inspection cycle.

Determination of Rule's Effective Date

    Since this AD action does not affect any airplane that is currently 
on the U.S. register, it has no adverse economic impact and imposes no 
additional burden on any person. Therefore, prior notice and public 
procedures hereon are unnecessary and the amendment may be made 
effective in less than 30 days after publication in the Federal 
Register.

Comments Invited

    Although this action is in the form of a final rule and was not 
preceded by notice and opportunity for public comment, comments are 
invited on this rule. Interested persons are invited to comment on this 
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 under the caption 
ADDRESSES. All communications received on or before the closing date 
for comments will be considered, and this rule may be amended in light 
of the comments received. Factual information that supports the 
commenter's ideas and suggestions is extremely helpful in evaluating 
the effectiveness of the AD action and determining whether additional 
rulemaking action would be needed.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the rule that might 
suggest a need to modify the 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 that 
summarizes each FAA-public contact concerned with the substance of this 
AD will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this rule must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 99-NM-61-AD.'' The postcard will be date stamped and 
returned to the commenter.

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:

99-16-10  Boeing: Amendment 39-11245. Docket 99-NM-61-AD.

    Applicability: Model 747-400 series airplanes as listed in 
Flight Structures Alert Service Bulletins 92FS082-53-A1, 92FS024-53-
A1, and 94FS409-53-A2, all dated March 2, 1999, and 94FS448-53-A1, 
dated February 12, 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 (d) 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 detect and repair fatigue cracking of the E-42 satellite 
communications (SATCOM) rack and its supporting structure, which 
could result in the SATCOM equipment falling from the rack, loss of 
SATCOM capabilities, injury to passengers, and reduced 
controllability of the airplane, accomplish the following:

Initial and Repetitive Inspections

    (a) Perform a detailed visual inspection of the E-42 SATCOM rack 
and fuselage (supporting) structure to detect fatigue cracking of 
the area surrounding the fastener holes, and to detect broken or 
missing fasteners, at the time specified in paragraph (a)(1) or 
(a)(2) of this AD, as applicable; in accordance with Flight 
Structures Alert Service Bulletin 92FS082-53-A1, 92FS024-53-A1, or 
94FS409-53-A2, all dated March 2, 1999; or 94FS448-53-A1, dated 
February 12, 1999, as applicable. Thereafter, repeat the inspection 
at intervals not to exceed 3,000 flight hours.
    (1) For all airplanes identified as Group 1 in the applicable 
alert service bulletin: Inspect within 30 days after the effective 
date of this AD.
    (2) For all airplanes identified as Group 2 in the applicable 
alert service bulletin: Inspect within 90 days after the effective 
date of this AD.

    Note 2: For the purposes of this AD, a detailed 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 any fatigue cracking is found, or if any fastener is 
broken or missing during any inspection required by paragraph (a) of 
this AD, prior to further flight, repair in accordance with a method 
approved by the Manager, Los Angeles Aircraft Certification Office 
(ACO), FAA, Transport Airplane Directorate. Thereafter, repeat the 
inspection required by paragraph (a) of this AD, at intervals not to 
exceed 3,000 flight hours.

Reporting Requirements

    (c) Submit a report of the initial inspection findings (positive 
and negative) to the

[[Page 43056]]

Manager, Los Angeles ACO, 3960 Paramount Boulevard, Lakewood, 
California 90712-4137; telephone (562) 627-5322; fax (562) 627-5210; 
at the applicable time specified in paragraph (c)(1) or (c)(2) of 
the AD, as applicable. The report must include the initial 
inspection results, a description of any discrepancy found, the 
airplane serial number, number of landings, and flight hours on the 
airplane, and, when possible, sketches and photographs of the 
inspected area. Information collection requirements contained in 
this regulation have been approved by the Office of Management and 
Budget (OMB) under the provisions of the Paperwork Reduction Act of 
1980 (44 U.S.C. 3501 et seq.) and have been assigned OMB Control 
Number 2120-0056.
    (1) For airplanes on which the initial inspection is 
accomplished after the effective date of this AD: Submit the report 
within 10 days after performing the inspection required by paragraph 
(a) of this AD.
    (2) For airplanes on which the initial inspection has been 
accomplished prior to the effective date of this AD: Submit the 
report within 30 days after the effective date of this AD.

Alternative Methods of Compliance

    (d) 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 ACO. 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 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Los Angeles ACO.

Special Flight Permits

    (e) 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, provided that all the 
equipment is removed from the E-42 SATCOM rack.

Incorporation by Reference

    (f) The inspections shall be done in accordance with Flight 
Structures Alert Service Bulletin 92FS082-53-A1, dated March 2, 
1999; Flight Structures Alert Service Bulletin 92FS024-53-A1, dated 
March 2, 1999; Flight Structures Alert Service Bulletin 94FS409-53-
A2, dated March 2, 1999; or Flight Structures Alert Service Bulletin 
94FS448-53-A1, dated February 12, 1999, as applicable. 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 Flight Structures Inc., 4407 172nd 
Street NE, Arlington, Washington 98223. Copies may be inspected at 
the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., 
Renton, Washington; or at Los Angeles ACO, 3960 Paramount Boulevard, 
Lakewood, California 90712-4137; or at the Office of the Federal 
Register, 800 North Capitol Street, NW., suite 700, Washington, DC.
    (g) This amendment becomes effective on August 24, 1999.

    Issued in Renton, Washington, on July 29, 1999.
D.L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 99-20059 Filed 8-6-99; 8:45 am]
BILLING CODE 4910-13-U

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