[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]
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