[Federal Register Volume 64, Number 206 (Tuesday, October 26, 1999)]
[Rules and Regulations]
[Pages 57553-57555]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-27561]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-178-AD; Amendment 39-11387; AD 99-22-09]
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 an inspection of the crew rest area heat exchangers to 
detect deflection or interference with the flight control cables; and 
various follow-on actions. This action also requires replacement of 
certain nutplate attachment rivets that attach the heat exchangers to 
the airframe with stronger rivets. This amendment is prompted by a 
report of interference between insulation blankets adjacent to the heat 
exchangers and flight control cables. The actions specified in this AD 
are intended to prevent a reduction in maximum rudder and elevator 
surface deflection due to the separation of heat exchangers from the 
body frame, which could result in reduced controllability of the 
airplane.

DATES: Effective November 10, 1999.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of November 10, 1999.
    Comments for inclusion in the Rules Docket must be received on or 
before December 27, 1999.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 99-NM-178-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056.
    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 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.

FOR FURTHER INFORMATION CONTACT: Barbara Mudrovich, Aerospace Engineer, 
System 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: The FAA has received a report indicating 
that the rudder and elevator of a Boeing Model 747-400 series airplane 
were ``stiff.'' Further investigation revealed that the nutplate 
attachment rivets that attach the crew rest area (CRA) heat exchangers 
to the airframe at station 1920 had failed. When the CRA air supply fan 
was on, air pressure caused the heat exchangers to deflect downwards 
and push adjacent insulation blankets into the flight control cables, 
causing the stiffness of the flight controls. This condition, if not 
corrected, could result in reduced maximum deflection of the rudder and 
elevator surfaces, which could result in reduced controllability of the 
airplane.
    Examination of failed rivets revealed that the rivets were not made 
of 2017-T4 aluminum, which was the rivet material specified in the 
engineering drawings. Instead, the rivets were made of lower-strength 
1100-F aluminum. The airplane manufacturer has determined that rivets 
made of the proper material were installed during production on 
airplanes after line number 1205.

Explanation of Relevant Service Information

    The FAA has reviewed and approved Boeing Alert Service Bulletin 
747-53A2430, dated June 10, 1999, which describes procedures for 
inspection of the CRA heat exchangers to detect deflection or 
interference with the flight control cables; and an inspection of the 
heat exchanger panels, pitot-static tubes, and air distribution ducts 
in that area to detect damage, if necessary. If any damage is detected, 
the alert service bulletin specifies to contact the manufacturer for 
repair instructions. The alert service bulletin also describes 
procedures for performing an electrical conductivity measurement of the 
nutplate attachment rivets that attach the heat exchangers to the 
airframe to determine the rivet material, and replacement of certain 
rivets with stronger rivets. Accomplishment of the actions specified in 
the alert service bulletin is intended to adequately address the 
identified unsafe condition.

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 prevent a reduction in maximum rudder and elevator 
surface deflection due to the separation of heat exchangers from the 
body frame, which could result in reduced controllability of the 
airplane. This AD requires accomplishment of the actions specified in 
the alert service bulletin described previously, except as described 
below.

Differences Between Rule and Alert Service Bulletin

    Operators should note that, although the alert service bulletin 
specifies that the manufacturer may be contacted for disposition of 
certain repair conditions, this AD requires the repair of those 
conditions to be accomplished in accordance with a method approved by 
the FAA.

Cost Impact

    None of the 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 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 2 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 inspection 
would be $120 per airplane.
    It would require approximately 3 hours to accomplish the required 
replacement, at an average labor rate of

[[Page 57554]]

$60 per work hour. Required parts would cost approximately $17 per 
airplane. Based on these figures, the cost impact of this replacement 
would be $197 per airplane.

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-178-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:

99-22-09  Boeing: Amendment 39-11387. Docket 99-NM-178-AD.

    Applicability: Model 747-400 series airplanes; as listed in 
Boeing Alert Service Bulletin 747-53A2430, dated June 10, 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 prevent a reduction in maximum rudder and elevator surface 
deflection due to the separation of heat exchangers from the body 
frame, which could result in reduced controllability of the 
airplane, accomplish the following:

One-Time Inspection

    (a) Within 400 flight hours or 30 days after the effective date 
of the AD, whichever occurs earlier, perform a one-time general 
visual inspection of the crew rest area (CRA) heat exchangers to 
detect deflection or interference with the flight control cables, in 
accordance with Boeing Alert Service Bulletin 747-53A2430, dated 
June 10, 1999.

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

Replacement

    (b) If no deflection or interference is detected, within 6,000 
flight hours after accomplishment of the inspection required by 
paragraph (a) of this AD, measure the electrical conductivity of the 
nutplate attachment rivets that attach the heat exchangers to the 
airframe at station 1920 to determine the rivet material, in 
accordance with Boeing Alert Service Bulletin 747-53A2430, dated 
June 10, 1999. Prior to further flight, replace any rivets not made 
of 2017-T4 aluminum with rivets made of 2017-T4 aluminum, in 
accordance with the alert service bulletin.
    (c) If any deflection or interference is detected during the 
inspection required by paragraph (a) of this AD, prior to further 
flight, accomplish paragraphs (c)(1) and (c)(2) of this AD.
    (1) Perform a one-time general visual inspection of the CRA heat 
exchanger panels, pitot-static tubes, and air distribution ducts in the 
area of station 1920 to detect damage, in accordance with Boeing Alert 
Service Bulletin 747-53A2430, dated June 10, 1999. If any damage is 
detected, prior to further flight, repair in accordance with a method 
approved by the Manager, Seattle Aircraft Certification Office (ACO), 
FAA, Transport Airplane Directorate. 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.
    (2) Remove the nutplates and attachment rivets that attach the heat 
exchangers to the airframe at station 1920, and replace with new 
nutplates and rivets made of 2017-T4 aluminum,

[[Page 57555]]

in accordance with Boeing Alert Service Bulletin 747-53A2430, dated 
June 10, 1999.

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, 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

    (e) 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.

Incorporation by Reference

    (f) Except as provided by paragraph (c)(1) of this AD, the 
actions shall be done in accordance with Boeing Alert Service 
Bulletin 747-53A2430, dated June 10, 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 the Office of the Federal Register, 800 North 
Capitol Street, NW., suite 700, Washington, DC.
    (g) This amendment becomes effective on November 10, 1999.

    Issued in Renton, Washington, on October 15, 1999.
D.L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 99-27561 Filed 10-25-99; 8:45 am]
BILLING CODE 4910-13-U