[Federal Register Volume 71, Number 119 (Wednesday, June 21, 2006)]
[Proposed Rules]
[Pages 35581-35584]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E6-9721]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2006-25087; Directorate Identifier 2006-NM-053-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 747 Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to supersede an existing airworthiness 
directive (AD) that applies to all Boeing Model 747 airplanes. The 
existing AD currently requires a one-time inspection to determine 
whether the outer cylinder of the wing landing gear has certain part 
numbers (P/Ns), and replacement of the outer cylinder of the wing 
landing gear with a new, improved, or reworked part if necessary. The 
existing AD also requires removal of the load evening system, if such a 
system is installed. For certain airplanes, this proposed AD would 
require an additional one-time inspection to determine whether the 
outer cylinder has a certain other P/N. For those certain airplanes, 
this proposed AD would also require replacement of the outer cylinder 
with a reworked or new, improved part and related investigative/
corrective actions, if necessary. This proposed AD results from 
identification of an additional unsafe part. We are proposing this AD 
to prevent fracture of the outer cylinder of the wing landing gear, 
which could result in collapse of the wing landing gear.

DATES: We must receive comments on this proposed AD by August 7, 2006.

ADDRESSES: Use one of the following addresses to submit comments on 
this proposed AD.
     DOT Docket Web site: Go to http://dms.dot.gov and follow 
the instructions for sending your comments electronically.
     Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your 
comments electronically.
     Mail: Docket Management Facility; U.S. Department of 
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, 
Washington, DC 20590.
     Fax: (202) 493-2251.
     Hand Delivery: Room PL-401 on the plaza level of the 
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, 
Washington 98124-2207, for service information identified in this 
proposed AD.

FOR FURTHER INFORMATION CONTACT: Nicholas Kusz, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
917-6432; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to submit any relevant written data, views, or 
arguments regarding this proposed AD. Send your comments to an address 
listed in the ADDRESSES section. Include the docket number ``Docket No. 
FAA-2006-25087; Directorate Identifier 2006-NM-053-AD'' at the 
beginning of your comments. We specifically invite comments on the 
overall regulatory, economic, environmental, and energy aspects of the 
proposed AD. We will consider all comments received by the closing date 
and may amend the proposed AD in light of those comments.
    We will post all comments we receive, without change, to http://dms.dot.gov, including any personal information you provide. We will 
also post a report summarizing each substantive verbal contact with FAA 
personnel concerning this proposed AD. Using the search function of 
that Web site, anyone can find and read the comments in any of our 
dockets, including the name of the individual who sent the comment (or 
signed the comment on behalf of an association, business, labor union, 
etc.). You may review the DOT's complete Privacy Act Statement in the 
Federal Register published on April 11, 2000 (65 FR 19477-78), or may 
can visit http://dms.dot.gov.

Examining the Docket

    You may examine the AD docket on the Internet at http://dms.dot.gov, or in person at the Docket Management Facility office 
between 9 a.m. and 5 p.m., Monday through Friday, except

[[Page 35582]]

Federal holidays. The Docket Management Facility office (telephone 
(800) 647-5227) is located on the plaza level of the Nassif Building at 
the DOT street address stated in the ADDRESSES section. Comments will 
be available in the AD docket shortly after the Docket Management 
System receives them.

Discussion

    On July 27, 2004, we issued AD 2004-16-05, amendment 39-13761 (69 
FR 48359, August 10, 2004), for all Boeing Model 747 airplanes. That AD 
requires a one-time inspection to determine whether the outer cylinder 
of the wing landing gear has certain part numbers (P/Ns), and 
replacement of the outer cylinder of the wing landing gear with a new, 
improved, or reworked part if necessary. That AD also requires removal 
of the load evening system, if such a system is installed. That AD 
resulted from reports that the outer cylinder of the wing landing gear 
was found cracked or fractured on Model 747 airplanes. We issued that 
AD to prevent fracture of the outer cylinder of the wing landing gear, 
which could result in collapse of the wing landing gear.

Actions Since Existing AD Was Issued

    Since we issued AD 2004-16-05, Boeing has published Service 
Bulletin 747-32-2472, Revision 1, dated February 23, 2006, to identify 
an outer cylinder, P/N 65B01382-( ), which was inadvertently omitted 
from the original issue of the service bulletin, dated November 30, 
2000. We referenced the original service bulletin as the appropriate 
source of service information for accomplishing the inspection and 
replacement required by the existing AD. (The procedures in Revision 1 
are essentially the same as those in the original service bulletin.) P/
N 65B01382-( ) has chrome plating on its inner surface, similar to the 
other unsafe parts identified in the original service bulletin and 
existing AD. Therefore, P/N 65B01382-( ) is also subject to the same 
unsafe condition addressed by the existing AD.
    Since P/N 65B01382-( ) was fitted exclusively to Model 747-100, 
747-100B, 747-100B SUD, and 747SR series airplanes, this NPRM proposes 
to require an additional one-time inspection to determine the P/Ns of 
the outer cylinder of the wing landing only on these airplanes. For any 
of these airplanes equipped with a load evening system, this NPRM would 
also require removal of that system before replacing P/N 65B01382-( ) 
with a reworked or new, improved part if applicable. We have added that 
requirement to paragraphs (h) and (j) of this NPRM. (Paragraph (h) of 
the NPRM corresponds to paragraph (c) of the existing AD.)

Relevant Service Information

    We have reviewed Revision 1 of Boeing Service Bulletin 747-32-2472. 
The service bulletin describes procedures for doing a one-time 
inspection to determine the P/N of the outer cylinder of the wing 
landing gear. The service bulletin also describes procedures for 
replacing the outer cylinder with a reworked or new part and doing 
related investigative and corrective actions, if an outer cylinder 
having P/N 65B01212-( ), 65B01382-( ), 65B01430-3, or 65B01430-4 is 
installed on an airplane. The related investigative actions include the 
following:
     Doing a nital etch test of the upper inner surface of the 
outer cylinder for chrome plating.
     Doing a magnetic particle inspection of the outer cylinder 
for any cracking.
     Doing a nital etch inspection of inner surface of the 
outer cylinder for heat damage.
     Marking the outer cylinder to indicate that part has been 
reworked.
The corrective actions include the following:
     Removing any chrome plating found on the upper inner 
surface of the outer cylinder.
     Reworking the outer cylinder to remove any cracking or 
heat damage.
    Accomplishing the actions specified in the service information is 
intended to adequately address the unsafe condition.

FAA's Determination and Requirements of the Proposed AD

    We have evaluated all pertinent information and identified an 
unsafe condition that is likely to develop on other airplanes of the 
same type design. For this reason, we are proposing this AD, which 
would supersede AD 2004-16-05 and would retain the requirements of the 
existing AD. This proposed AD would also require accomplishing the 
actions specified in the service bulletin described previously, except 
as discussed under ``Differences Between the Proposed AD and Service 
Bulletin.''

Differences Between the Proposed AD and Service Bulletin

    Service Bulletin 747-32-2472, Revision 1, specifies that operators 
may accomplish certain related investigative and corrective actions 
using an ``approved equivalent procedure.'' However, this proposed AD 
would require operators to accomplish the actions using the procedures 
specified in a certain chapter(s) of the Boeing 747 SOPM or OHM, as 
applicable. An ``approved equivalent procedure'' may be used only if 
approved as an alternative method of compliance according to paragraph 
(m) of this AD.

Changes to Existing AD

    This proposed AD would retain certain requirements of AD 2004-16-
05. Since AD 2004-16-05 was issued, the AD format has been revised, and 
certain paragraphs have been rearranged. As a result, the corresponding 
paragraph identifiers have changed in this proposed AD, as listed in 
the following table:

                      Revised Paragraph Identifiers
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                                           Corresponding  requirement in
      Requirement in AD 2004-16-05               this proposed  AD
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Paragraph (a)...........................  Paragraph (f).
Paragraph (b)...........................  Paragraph (g).
Paragraph (c)...........................  Paragraph (h).
Paragraph (d)...........................  Paragraph (i).
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    We have added reference to Revision 1 of Boeing Service Bulletin 
747-32-2472 in paragraphs (f) and (g) of this proposed AD, since the 
procedures in Revision 1 are essentially the same as those in the 
original issue of the service bulletin.
    We have revised the ``Alternative Methods of Compliance (AMOCs)'' 
paragraph in this proposed AD to clarify the delegation authority for 
Authorized Representatives for the Boeing Commercial Airplanes 
Delegation Option Authorization.
    We have also revised this proposed AD to clarify the appropriate 
procedure for notifying the principal inspector before using any 
approved AMOC on any airplane to which the AMOC applies.

Costs of Compliance

    There are about 1,106 Model 747 airplanes of the affected design in 
the worldwide fleet. Of those airplanes, there are about 66 Model 747-
100, 747-100B, 747-100B SUD, and 747SR series airplanes of the affected 
design in the worldwide fleet that would be subject to the new proposed 
actions. The following table provides the estimated costs, at an 
average labor rate of $80 per hour, for U.S. operators to comply with 
this proposed AD.

[[Page 35583]]



                                                 Estimated Costs
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                                                                                  Number of U.S.-
             Action                 Work hours         Parts         Cost per       registered      Fleet cost
                                                                     airplane        airplanes
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Inspection for all airplanes                   1            None             $80             256         $20,480
 (required by AD 2004-16-05)....
Removal of the load evening                  240          $2,392          21,592             256       5,527,552
 system (required by AD 2004-16-
 05)............................
Inspection for certain airplanes               1            None              80              21           1,680
 (new proposed action)..........
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    If required, the chrome removal and inspections for cracking or 
heat damage would take about 12 work hours per airplane, at an average 
labor rate of $80 per work hour. Based on these figures, the estimated 
cost of these actions is $960 per airplane.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, Section 106, describes the 
authority of the FAA Administrator. Subtitle VII, Aviation Programs, 
describes in more detail the scope of the Agency's authority.
    We are issuing this rulemaking under the authority described in 
Subtitle VII, Part A, Subpart III, Section 44701, ``General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation is within 
the scope of that authority because it addresses an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.

Regulatory Findings

    We have determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD 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.
    For the reasons discussed above, I certify that the 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. 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.
    We prepared a regulatory evaluation of the estimated costs to 
comply with this proposed AD and placed it in the AD docket. See the 
ADDRESSES section for a location to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 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. The Federal Aviation Administration (FAA) amends Sec.  39.13 by 
removing amendment 39-13761 (69 FR 48359, August 10, 2004) and adding 
the following new airworthiness directive (AD):

Boeing: Docket No. FAA-2006-25087; Directorate Identifier 2006-NM-
053-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by August 7, 
2006.

Affected ADs

    (b) This AD supersedes AD 2004-16-05.

Applicability

    (c) This AD applies to all Boeing Model 747-100, 747-100B, 747-
100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 
747-400F, 747SR, and 747SP series airplanes, certificated in any 
category.

Unsafe Condition

    (d) This AD results from identification of an additional unsafe 
outer cylinder of the wing landing gear. We are issuing this AD to 
prevent fracture of the outer cylinder of the wing landing gear, 
which could result in collapse of the wing landing gear.

Compliance

    (e) You are responsible for having the actions required by this 
AD performed within the compliance times specified, unless the 
actions have already been done.

Restatement of Requirements of AD 2004-16-05

Inspection to Determine Part Number

    (f) Within 36 months after September 14, 2004 (the effective 
date of AD 2004-16-05), perform a one-time inspection to determine 
the part number (P/N) of the outer cylinder of the wing landing gear 
on both sides of the airplane, per the Accomplishment Instructions 
of Boeing Service Bulletin 747-32-2472, dated November 30, 2000, or 
Revision 1, dated February 23, 2006. Instead of inspecting the outer 
cylinder of the wing landing gear, a review of airplane maintenance 
records is acceptable if the detailed P/N of the outer cylinder of 
the wing landing gear (not just a higher-level assembly) can be 
positively determined from that review.
    (1) If no outer cylinder having P/N 65B01212-( ) (where ``( )'' 
is any dash number of that part number), 65B01430-3, or 65B01430-4 
is found: No further action is required by this paragraph.
    (2) If any outer cylinder having P/N 65B01212-( ) (where ``( )'' 
is any dash number of that part number), 65B01430-3, or 65B01430-4 
is found: Accomplish paragraph (g) of this AD.

Replacement of Outer Cylinder

    (g) For any outer cylinder identified in paragraph (f)(2) of 
this AD: Within 36 months after September 14, 2004, replace the 
outer cylinder on the wing landing gear with a new, improved part or 
a part that has been inspected and reworked per the Accomplishment 
Instructions of Boeing Service Bulletin 747-32-2472, dated November 
30, 2000; or Revision 1, dated February 23, 2006, except as provided 
by paragraph (k) of this AD. The rework procedures described in the 
service bulletin, if accomplished, include performing a one-time 
nital etch inspection of the upper inner surface of the outer 
cylinder for chrome plating; removing any chrome plating that is 
present; performing a one-time magnetic particle inspection for 
cracking of the outer cylinder; performing a nital etch inspection 
for heat damage of the outer cylinder; reworking the outer cylinder, 
as applicable; and marking the outer cylinder to indicate that the 
service bulletin has been accomplished.

Removal of the Load Evening System

    (h) For airplanes identified in Boeing Service Bulletin 747-32-
2131, Revision 2, dated March 15, 1974: Before performing the 
requirements of paragraph (g) or (j) of this AD, as applicable, 
remove the load evening system installed on the wing landing gear,

[[Page 35584]]

per the Accomplishment Instructions of the service bulletin.

New Requirements of This AD

Inspection To Determine Outer Cylinder P/N on Certain Airplanes

    (i) For Model 747-100, 747-100B, 747-100B SUD, and 747SR series 
airplanes: Within 36 months after the effective date of this AD, do 
a one-time inspection to determine the P/N of the outer cylinder of 
the wing landing gear on both sides of the airplane, in accordance 
with the Accomplishment Instructions of Boeing Service Bulletin 747-
32-2472, Revision 1, dated February 23, 2006. Instead of inspecting 
the outer cylinder of the wing landing gear, a review of airplane 
maintenance records is acceptable if the detailed P/N of the outer 
cylinder of the wing landing gear (not just a higher-level assembly) 
can be positively determined from that review.
    (1) If no outer cylinder having P/N 65B01382-( ) is found: No 
further action is required by this paragraph.
    (2) If any outer cylinder having P/N 65B01382-( ) is found: 
Accomplish paragraph (j) of this AD.

Replacement of a Certain Outer Cylinder

    (j) For any outer cylinder identified in paragraph (i)(2) of 
this AD: Within 36 months after the effective date of this AD, 
replace the outer cylinder on the wing landing gear with a reworked 
or new, improved part, and do the related investigative actions and 
all applicable corrective actions before further flight after the 
replacement, by accomplishing all of the applicable actions 
specified in 3.B.2 and 3.B.3 of the Accomplishment Instructions of 
Boeing Service Bulletin 747-32-2472, Revision 1, dated February 23, 
2006; except as provided by paragraph (k) of this AD. If applicable, 
do the actions specified in paragraph (h) of this AD before 
accomplishing the actions specified in this paragraph.

Exception to Revision 1 of the Service Bulletin

    (k) Where Service Bulletin 747-32-2472, Revision 1, dated 
February 23, 2006, specifies that the related investigative and 
corrective actions may be accomplished using an operator's 
``equivalent procedure:'' The related investigative and corrective 
actions must be accomplished in accordance with the chapter(s) of 
the applicable Boeing 747 SOPM or OHM specified in the service 
bulletin.

Parts Installation

    (l) As of September 14, 2004, no person may install, on any 
airplane, an outer cylinder of the wing landing gear if the outer 
cylinder has P/N 65B01212-( ), 65B01430-3, or 65B01430-4, unless the 
outer cylinder has been inspected, reworked, and marked to indicate 
that Boeing Service Bulletin 747-32-2472, dated November 30, 2000, 
or Revision 1, dated February 23, 2006, has been accomplished. As of 
the effective date of this AD, no person may install an outer 
cylinder, P/N 65B01382-( ), of the wing landing gear on any 
airplane, unless the outer cylinder has been inspected, reworked, 
and marked to indicate that Boeing Service Bulletin 747-32-2472, 
Revision 1, dated February 23, 2006, has been accomplished.

Alternative Methods of Compliance (AMOCs)

    (m)(1) The Manager, Seattle Aircraft Certification Office (ACO), 
FAA, has the authority to approve AMOCs for this AD, if requested in 
accordance with the procedures found in 14 CFR 39.19.
    (2) Before using any AMOC approved in accordance with Sec.  
39.19 on any airplane to which the AMOC applies, notify the 
appropriate principal inspector in the FAA Flight Standards 
Certificate Holding District Office.
    (3) An AMOC that provides an acceptable level of safety may be 
used for any repair required by this AD, if it is approved by an 
Authorized Representative for the Boeing Commercial Airplanes 
Delegation Option Authorization Organization who has been authorized 
by the Manager, Seattle ACO, to make those findings. For a repair 
method to be approved, the repair must meet the certification basis 
of the airplane, and the approval must specifically refer to this 
AD.
    (4) AMOCs approved previously in accordance with AD 2004-16-05, 
amendment 39-13761, are approved as AMOCs for the corresponding 
provisions of paragraphs (f), (g), and (h) of this AD.

    Issued in Renton, Washington, on June 13, 2006.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
 [FR Doc. E6-9721 Filed 6-20-06; 8:45 am]
BILLING CODE 4910-13-P