[Federal Register: October 18, 2006 (Volume 71, Number 201)]
[Rules and Regulations]               
[Page 61391-61395]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr18oc06-5]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000-NM-360-AD; Amendment 39-14789; AD 2006-21-05]
RIN 2120-AA64

 
Airworthiness Directives; Boeing Model 747-400, 777-200, and 777-
300 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to certain Boeing Model 747-400, 777-200, and 777-300 series 
airplanes. This AD requires, for certain airplanes, replacing the cell 
stack of the flight deck humidifier with a supplier-tested cell stack, 
or replacing the cell stack with a blanking plate and subsequently 
deactivating the flight deck humidifier. For certain other airplanes, 
this AD requires an inspection of the flight deck humidifier to 
determine certain part numbers and replacing the cell stack if 
necessary. This AD also allows blanking plates to be replaced with cell 
stacks. The actions specified by this AD are intended to prevent an 
increased pressure drop across the humidifier and consequent reduced 
airflow to the flight deck, which could result in the inability to 
clear any smoke that might appear in the flight deck. This action is 
intended to address the identified unsafe condition.

DATES: Effective November 22, 2006.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of November 22, 2006.

ADDRESSES: The service information referenced in this AD may be 
obtained from Boeing Commercial Airplanes, 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.

FOR FURTHER INFORMATION CONTACT: Jeffrey S. Palmer, Aerospace Engineer, 
Cabin Safety and Environmental Systems Branch, ANM-150S, FAA, Seattle 
Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056; telephone (425) 917-6481; fax (425) 917-6590.

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 747-400, 777-
200, and 777-300 series airplanes was published as a second 
supplemental notice of proposed rulemaking (NPRM) in the Federal 
Register on January 4, 2006 (71 FR 299). That action proposed to 
require, for certain airplanes, replacing the cell stack of the flight 
deck humidifier with a supplier-tested cell stack, or replacing the 
cell stack with a blanking plate and subsequently deactivating the 
flight deck humidifier. For certain other airplanes, that action 
proposed to require an inspection of the flight deck humidifier to 
determine certain part numbers and replacing the cell stack if 
necessary. That action also proposed to allow blanking plates to be 
replaced with cell stacks. That action also proposed to add airplanes 
to the applicability.

Actions Since Second Supplemental NPRM (SNPRM) Was Issued

    Since we issued the second SNPRM, Boeing has issued Service 
Bulletin 747-21A2414, Revision 3, dated May 12, 2006; and Service 
Bulletin 777-21A0048, Revision 3, dated May 12, 2006. Boeing Alert 
Service Bulletin 747-21A2414, Revision 2, dated July 7, 2005; and 
Boeing Alert Service Bulletin 777-21A0048, Revision 2, dated July 14, 
2005, were referenced as the appropriate sources of service information 
for doing certain actions proposed in the second SNPRM. Both service 
bulletins, Revision 3, contain essentially the same procedures as the 
corresponding service bulletins, Revision 2. We have revised this final 
rule to refer to Revision 3 of these service bulletins.
    We have also added Boeing Alert Service Bulletin 747-21A2414, 
Revision 2, to paragraphs (b) and (g) of this final rule and added 
Boeing Alert Service Bulletin 777-21A0048, Revision 2, to paragraphs 
(e) and (h) of this final rule to allow credit for actions done in 
accordance with Revision 2 of the service bulletins.
    Operators should note that Boeing Service Bulletin 747-21A2414, 
Revision 3, dated May 12, 2006, specifies Group 1 as ``all 747-400 
airplanes with Hamilton Sundstrand flight deck humidifier 821486-01.'' 
However, the correct part number for the humidifier is 821486-1. We 
have added Note 1 to this final rule to indicate that Group 1 is 
identified as all 747-400 airplanes with Hamilton Sundstrand flight 
deck humidifier 821486-1.

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.

Support for the Second SNPRM

    Boeing, the manufacturer, concurs with the content of the second 
SNPRM.

Request To Remove Airplanes From the Second SNPRM

    United Airlines (UAL) does not agree with the contents of the 
second SNPRM for the Model 747-400 series airplanes and feels that 
regulatory action is not necessary to ensure the intent of the second 
SNPRM for these airplanes. UAL states that it took immediate steps to 
comply with Boeing and Hamilton Sundstrand service bulletins specified 
in the second SNPRM. UAL notes that because the reliability of the 
humidifier was extremely poor at the time that the cell stack concern 
was identified, the humidifier cell stacks have been

[[Page 61392]]

replaced many times since the year 2000. UAL states that the removed 
cell stacks were sent to Hamilton Sundstrand for repair and 
modification and that Hamilton Sundstrand is the sole source for repair 
and modification. Therefore, UAL concludes that the intent of the 
second SNPRM for the 747-400 airplanes can be satisfied by examining 
Hamilton Sundstrand's maintenance records for the cell stack.
    We disagree. Regulatory action is necessary to ensure that Model 
747-400 series airplanes do the actions in this final rule. A review by 
the airplane manufacturer of the Hamilton Sundstrand records shows that 
about 10 defective humidifier cell stacks are in circulation among the 
Model 747-400 fleet. This final rule will prevent any of those 
humidifiers, having cell stack part number (P/N) 821482-1, from being 
installed as replacements on any airplanes unless ``DEV 13433'' is 
marked next to the cell stack P/N. We have not changed the final rule 
in this regard.
    UAL also does not agree with the contents of the second SNPRM for 
the Model 777-200 series airplanes and feels that regulatory action is 
not necessary to ensure the intent of the second SNPRM for these 
airplanes. UAL states that the airplanes identified as Group 6 in 
Boeing Service Bulletin 777-21A0048, Revision 3, dated May 12, 2006, 
were added to the service bulletin because the airplanes were scheduled 
to have the humidifiers retrofitted as part of the crew rest project; 
however, the installation was canceled and no airplanes were 
retrofitted with the humidifiers.
    We disagree. Regulatory action is necessary to ensure that Model 
777-200 series airplanes do the actions in this final rule. A review by 
the airplane manufacturer of the Hamilton Sundstrand records shows that 
about 14 defective humidifier cell stacks are in circulation among the 
Model 777 fleet. This final rule will prevent any of those humidifiers, 
having cell stack P/N 822976-2, from being installed as replacements on 
any airplanes unless ``DEV 13433'' is marked next to the cell stack P/
N. We have not changed the final rule in this regard.

Request To Allow Compliance With Maintenance Records

    UAL also requests that if Model 747-400 series airplanes are not 
allowed to be removed from the requirements of the second SNPRM as 
requested above, then the only regulatory actions imposed on operators 
should be limited to demonstrating compliance through their own 
maintenance records.
    We partially agree with the commenter. In paragraph (c) of this 
final rule we do allow a review of airplane maintenance records to 
determine the P/N of the flight deck humidifier instead of doing the 
inspection. We have determined that a review of the maintenance records 
is also acceptable if it can be determined that the flight deck 
humidifier is not installed. We have revised paragraph (c) to state 
that ``instead of inspecting the flight deck humidifier, a review of 
airplane maintenance records along with any other applicable data is 
acceptable if the P/N of the flight deck humidifier can be positively 
determined from that review or if it can be positively determined that 
the flight deck humidifier is not installed on the airplane.''

Request To Allow Equivalent Blanking Plate Installation

    UAL also requests that we consider the blanking plate installation 
and humidifier system deactivation done in accordance with Boeing 
Service Bulletin 777-21-0087, dated June 17, 2004; and Hamilton 
Sundstrand Service Bulletin 816086-21-01, dated March 15, 2000; as 
equivalent to the blanking plate installation done in accordance with 
Boeing Alert Service Bulletin 777-21A0048, Revision 2, dated July 14, 
2005 (specified in paragraph (f) of the second SNPRM).
    The commenter states that it has deactivated the humidifiers and 
replaced the cell stacks with blanking plates on all Group 7 airplanes 
identified in Boeing Alert Service Bulletin 777-21-0048, registration 
numbers 09UA and 16UA-29UA, by doing the actions in Boeing Service 
Bulletin 777-21-0087 and Hamilton Sundstrand Service Bulletin 816086-
21-01. The commenter also notes that the airplane having registration 
number 09UA, was delivered with a deactivated humidifier and only 
needed modification by doing the blanking plate installation per 
Hamilton Sundstrand Service Bulletin 816086-21-01.
    We agree with the commenter. We have revised paragraph (f)(2)(ii) 
of this final rule to give credit for airplanes on which the 
replacement and deactivation are done in accordance with Boeing Service 
Bulletin 777-21-0087 and Hamilton Sundstrand Service Bulletin 816086-
21-01 for those Group 7 airplanes listed in Boeing Service Bulletin 
777-21-0087, dated June 17, 2004.
    We have also determined that a review of the maintenance records is 
acceptable instead of the inspection specified in paragraph (f) of this 
final rule if it can be determined that the flight deck humidifier is 
not installed. We have revised paragraph (f) to state that ``instead of 
inspecting the flight deck humidifier, a review of airplane maintenance 
records along with any other applicable data is acceptable if the P/N 
of the flight deck humidifier can be positively determined from that 
review or if it can be positively determined that the flight deck 
humidifier is not installed on the airplane.''

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 described 
previously. 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 176 airplanes of the affected design in the 
worldwide fleet. The FAA estimates that this AD affects 29 airplanes of 
U.S. registry. The cost per airplane ranges between $390 and $6,248 per 
airplane, depending on the actions chosen by the operator. The fleet 
cost estimate does not exceed $181,192.

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                        Work    Hourly                 Cost per
             Model/series                          Action              hours     rate    Parts cost    airplane
----------------------------------------------------------------------------------------------------------------
747-400, 777-200, 777-300............  Inspect flight deck                  1      $65           $0          $65
                                        humidifier for P/N and
                                        inspect flight deck
                                        humidifier cell stack for P/
                                        N.
747-400..............................  Replace cell stack with new          3       65        5,100        5,295
                                        or supplier-tested cell
                                        stack.
747-400..............................  Replace cell stack with              5       65            0          325
                                        blanking plate and
                                        deactivate humidifier.
777-200, 777-300.....................  Replace cell stack with              3       65            0          195
                                        blanking plate.

[[Page 61393]]


777-200, 777-300.....................  Replace cell stack with new          3       65        6,053        6,248
                                        or supplier-tested cell
                                        stack.
777-200, 777-300.....................  Replace blanking plate with          1       65        6,053        6,118
                                        supplier-tested cell stack.
----------------------------------------------------------------------------------------------------------------

    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. The cost impact figures discussed 
in AD rulemaking actions represent only the time necessary to perform 
the specific actions actually required by the AD. These figures 
typically do not include incidental costs, such as the time required to 
gain access and close up, planning time, or time necessitated by other 
administrative actions.

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 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

0
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

0
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]

0
2. Section 39.13 is amended by adding the following new airworthiness 
directive:

2006-21-05 Boeing: Amendment 39-14789. Docket 2000-NM-360-AD.

    Applicability: Model 747-400, 777-200, and 777-300 series 
airplanes, certificated in any category; as identified in Boeing 
Service Bulletin 747-21A2414, Revision 3, dated May 12, 2006; and 
Boeing Service Bulletin 777-21A0048, Revision 3, dated May 12, 2006.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent an increased pressure drop across the humidifier and 
consequent reduced airflow to the flight deck, which could result in 
the inability to clear any smoke that might appear in the flight 
deck, accomplish the following:

Cell Stack Replacement: Model 747-400 Series Airplanes

    (a) For Model 747-400 series airplanes identified as Group 1 in 
Boeing Service Bulletin 747-21A2414, Revision 3, dated May 12, 2006: 
Within 90 days after the effective date of this AD, do the 
replacement specified in paragraph (a)(1) or (a)(2) of this AD. For 
flight deck humidifiers with a blanking plate: If the blanking plate 
is removed and a new or supplier-tested cell stack is installed, the 
replacement must be done in accordance with the Accomplishment 
Instructions of Hamilton Sundstrand Service Bulletins 821486-21-01, 
dated March 15, 2000; and after the replacement, the flight deck 
humidifier may be activated in accordance with the Accomplishment 
Instructions of Boeing Service Bulletin 747-21-2405, Revision 4, 
dated July 29, 1999.

    Note 1: Boeing Service Bulletin 747-21A2414, Revision 3, dated 
May 12, 2006, specifies Group 1 as ``all 747-400 airplanes with 
Hamilton Sundstrand flight deck humidifier 821486-01.'' The correct 
part number (P/N) for the humidifier is 821486-1.

    (1) Replace the cell stack of the flight deck humidifier with a 
supplier-tested cell stack, in accordance with Part 1 of the 
Accomplishment Instructions of Boeing Service Bulletin 747-21A2414, 
Revision 3, dated May 12, 2006.
    (2) Replace the cell stack of the flight deck humidifier with a 
blanking plate and, before further flight, deactivate the flight 
deck humidifier, in accordance with Part 2 of the Accomplishment 
Instructions of Boeing Service Bulletin 747-21A2414, Revision 3, 
dated May 12, 2006.

    Note 2: Boeing Service Bulletin 747-21A2414, Revision 3, dated 
May 12, 2006, refers to Boeing Service Bulletin 747-21-2405, 
Revision 4, dated July 29, 1999, as an additional source of service 
information for deactivating the humidifier.


    Note 3: Boeing Service Bulletin 747-21A2414, Revision 3, dated 
May 12, 2006, refers to Hamilton Sundstrand Service Bulletin 821486-
21-01, dated March 15, 2000, as an additional source of service 
information for the cell stack replacements.

    (b) Replacement of the cell stack before the effective date of 
this AD in accordance with Boeing Alert Service Bulletin 747-
21A2414, dated April 13, 2000; Revision 1, dated October 26, 2000; 
or Revision 2, dated July 7, 2005; is acceptable for compliance with 
the applicable requirements of paragraphs (a)(1) and (a)(2) of this 
AD.

Inspections/Records Review: Model 747-400 Series Airplanes

    (c) For Model 747-400 series airplanes identified as Groups 2 
and 3 in Boeing Service Bulletin 747-21A2414, Revision 3, dated May 
12, 2006: Within 90 days after the effective date of this AD, 
inspect the flight deck humidifier to determine whether P/N 821486-1 
is installed, in accordance with Part 3 of the Accomplishment 
Instructions of Boeing Service Bulletin 747-21A2414, Revision 3, 
dated May 12, 2006. Instead of inspecting the flight deck 
humidifier, a

[[Page 61394]]

review of airplane maintenance records along with any other 
applicable data is acceptable if the P/N of the flight deck 
humidifier can be positively determined from that review or if it 
can be positively determined that the flight deck humidifier is not 
installed on the airplane.
    (1) If a P/N other than P/N 821486-1 is installed or if the 
flight deck humidifier is not installed, no further action is 
required by this paragraph.
    (2) If P/N 821486-1 is installed, inspect the flight deck 
humidifier cell stack to determine whether P/N 821482-1 is installed 
and ``DEV 13433'' is not marked next to the cell stack P/N, in 
accordance with Part 3 of the Accomplishment Instructions of the 
service bulletin. Instead of inspecting the flight deck humidifier 
cell stack, a review of airplane maintenance records is acceptable 
if the P/N, including whether ``DEV 13433'' is marked next to the P/
N, of the flight deck humidifier cell stack can be positively 
determined from that review.
    (i) If the cell stack has P/N 821482-2 or 1003111-2, or if ``DEV 
13433'' is marked next to P/N 821482-1, no further action is 
required by this paragraph.
    (ii) If the cell stack has P/N 821482-1 and does not have ``DEV 
13433'' marked next to the cell stack P/N: Before further flight, do 
the replacement specified in paragraph (a) of this AD.

Cell Stack Replacement: Model 777-200 and -300 Series Airplanes

    (d) For Model 777-200 and 777-300 series airplanes identified as 
Groups 1 through 5 in Boeing Service Bulletin 777-21A0048, Revision 
3, dated May 12, 2006: Within 90 days after the effective date of 
this AD, do the replacement specified in paragraph (d)(1) or (d)(2) 
of this AD. For flight deck humidifiers with a blanking plate: If a 
blanking plate is removed and a new or supplier-tested cell stack 
installed, the cell stack installation must be done in accordance 
with Part 3 of the Accomplishment Instructions of Boeing Service 
Bulletin 777-21A0048, Revision 3, dated May 12, 2006; and after the 
installation, the humidifier system may be activated in accordance 
with Accomplishment Instructions of Boeing Service Bulletin 777-21-
0035, Revision 1, dated October 19, 2000.
    (1) Replace the cell stack with a blanking plate, in accordance 
with Part 1 of the Accomplishment Instructions of Boeing Service 
Bulletin 777-21A0048, Revision 3, dated May 12, 2006; and, before 
further flight, deactivate the humidifier system in accordance with 
a method approved by the Manager, Seattle Aircraft Certification 
Office (ACO), FAA, or in accordance with data meeting the 
certification basis of the airplane approved by an Authorized 
Representative for the Boeing Commercial Airplanes Delegation Option 
Authorization who has been authorized by the Manager, Seattle ACO, 
to make those findings. For a deactivation method to be approved, 
the deactivation must meet the certification basis of the airplane, 
and the approval must specifically reference this AD.
    (2) Replace the cell stack with a supplier-tested cell stack, in 
accordance with Part 2 of the Accomplishment Instructions of Boeing 
Service Bulletin 777-21A0048, Revision 3, dated May 12, 2006.

    Note 4: Boeing Service Bulletin 777-21A0048, Revision 3, dated 
May 12, 2006, refers to Hamilton Sundstrand Service Bulletin 816086-
21-01, dated March 15, 2000, as an additional source of service 
information for the cell stack replacement.

    (e) Replacement of the cell stack before the effective date of 
this AD in accordance with Boeing Service Bulletin 777-21A0048, 
Revision 1, dated September 7, 2000; or Boeing Alert Service 
Bulletin 777-21A0048, Revision 2, dated July 14, 2005; is acceptable 
for compliance with the applicable requirements of paragraphs (d)(1) 
and (d)(2) of this AD.

Inspections/Records Review: Model 777-200 and -300 Series Airplanes

    (f) For Model 777-200 and 777-300 series airplanes identified as 
Groups 6 and 7 in Boeing Service Bulletin 777-21A0048, Revision 3, 
dated May 12, 2006: Within 90 days after the effective date of this 
AD, inspect the flight deck humidifier to determine if it is P/N 
816086-1, in accordance with Part 4 of the Accomplishment 
Instructions of Boeing Service Bulletin 777-21A0048, Revision 3, 
dated May 12, 2006. Instead of inspecting the flight deck 
humidifier, a review of airplane maintenance records along with any 
other applicable data is acceptable if the P/N of the flight deck 
humidifier can be positively determined from that review or if it 
can be positively determined that the flight deck humidifier is not 
installed on the airplane.
    (1) If a P/N other than P/N 816086-1 is installed or if the 
flight deck humidifier is not installed, no further action is 
required by this paragraph.
    (2) If P/N 816086-1 is installed, inspect the flight deck 
humidifier cell stack to determine whether P/N 822976-2 is installed 
and ``DEV 13433'' is not marked next to the cell stack P/N, in 
accordance with Part 4 of the Accomplishment Instructions of the 
service bulletin. Instead of inspecting the flight deck humidifier 
cell stack, a review of airplane maintenance records is acceptable 
if the P/N, including whether ``DEV 13433'' is marked next to the P/
N, of the flight deck humidifier cell stack can be positively 
determined from that review.
    (i) If the cell stack has P/N 822976-3 or 1003111-1, or if ``DEV 
13433'' is marked next to P/N 822976-2, no further action is 
required by this paragraph.
    (ii) If the cell stack has P/N 822976-2 and does not have ``DEV 
13433'' marked next to the cell stack P/N, before further flight, do 
the replacement specified in paragraph (d) of this AD. Doing the 
replacement of the cell stack with a blanking plate, in accordance 
with paragraph 3.A. of the Accomplishment Instructions of Hamilton 
Sundstrand Service Bulletin 816086-21-01, dated March 15, 2000; and 
the deactivation of the humidifier system, in accordance with the 
Accomplishment Instructions of Boeing Service Bulletin 777-21-0087, 
dated June 17, 2004; is acceptable for compliance with paragraph 
(d)(1) of this AD for those Group 7 airplanes listed in Boeing 
Service Bulletin 777-21-0087, dated June 17, 2004.

Actions Accomplished According to Previous Issue of Service Bulletin

    (g) Inspections accomplished before the effective date of this 
AD in accordance with Boeing Alert Service Bulletin 747-21A2414, 
Revision 2, dated July 7, 2005, are considered acceptable for 
compliance with the corresponding action specified in paragraph (c) 
of this AD.
    (h) Inspections accomplished before the effective date of this 
AD in accordance with Boeing Alert Service Bulletin 777-21A0048, 
Revision 2, dated July 14, 2005, are considered acceptable for 
compliance with the corresponding action specified in paragraph (f) 
of this AD.

Parts Installation

    (i) On Model 747-400 series airplanes: As of the effective date 
of this AD, no person may install a flight deck humidifier cell 
stack having P/N 821482-1, unless ``DEV 13433'' is also marked next 
to the cell stack P/N.
    (j) On Model 777-200 and 777-300 series airplanes: As of the 
effective date of this AD, no person may install a flight deck 
humidifier cell stack having P/N 822976-2, unless ``DEV 13433'' is 
also marked next to the cell stack P/N.

Alternative Methods of Compliance

    (k)(1) In accordance with 14 CFR 39.19, the Manager, Seattle 
ACO, is authorized to approve alternative methods of compliance for 
this AD.
    (2) Before using any AMOC approved in accordance with 14 CFR 
39.19 on any airplane to which the AMOC applies, notify the 
appropriate principal inspector in the FAA Flight Standards 
Certificate Holding District Office.

Incorporation by Reference

    (l) Unless otherwise specified in this AD, the actions must be 
done in accordance with the applicable service bulletins listed in 
Table 1 of this AD. 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. To get copies of this service information, 
contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, 
Washington 98124-2207. To inspect copies of this service 
information, go to the FAA, Transport Airplane Directorate, 1601 
Lind Avenue, SW., Renton, Washington. For information on the 
availability of this material at the NARA, call (202) 741-6030, or 
go to http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.
 


[[Page 61395]]



                                  Table 1.--Material Incorporated by Reference
----------------------------------------------------------------------------------------------------------------
           Service Bulletin                     Revision level                            Date
----------------------------------------------------------------------------------------------------------------
Boeing Service Bulletin 747-21A2414...  3.............................  May 12, 2006.
Boeing Service Bulletin 747-21-2405...  4.............................  July 29, 1999.
Boeing Service Bulletin 777-21A0048...  3.............................  May 12, 2006.
Boeing Service Bulletin 777-21-0035...  1.............................  October 19, 2000.
Boeing Service Bulletin 777-21-0087...  Original......................  June 17, 2004.
Hamilton Sundstrand Service Bulletin    Original......................  March 15, 2000.
 816086-21-01.
Hamilton Sundstrand Service Bulletin    Original......................  March 15, 2000.
 821486-21-01.
----------------------------------------------------------------------------------------------------------------

Effective Date

    (m) This amendment becomes effective on November 22, 2006.

    Issued in Renton, Washington, on October 6, 2006.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
 [FR Doc. E6-17187 Filed 10-17-06; 8:45 am]

BILLING CODE 4910-13-P