[Federal Register: October 12, 2006 (Volume 71, Number 197)]
[Proposed Rules]
[Page 60080-60083]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr12oc06-14]
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Proposed Rules
Federal Register
________________________________________________________________________
This section of the FEDERAL REGISTER contains notices to the public of
the proposed issuance of rules and regulations. The purpose of these
notices is to give interested persons an opportunity to participate in
the rule making prior to the adoption of the final rules.
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[[Page 60080]]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2006-26043; Directorate Identifier 2005-NM-010-AD]
RIN 2120-AA64
Airworthiness Directives; McDonnell Douglas Model 717-200
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 adopt a new airworthiness directive (AD)
for all McDonnell Douglas Model 717-200 airplanes. This proposed AD
would require inspecting the power conversion distribution unit (PCDU)
to determine its part number, and modifying certain PCDUs. This
proposed AD is prompted by reports of failed PCDUs, the loss of an
electrical bus, and the presence of a strong electrical burning odor in
the flight deck and forward cabin. We are proposing this AD to prevent
the loss of an electrical bus due to a PCDU failure, which could result
in an abnormally long time for all flight deck displays to reconfigure,
and consequent emergency landing.
DATES: We must receive comments on this proposed AD by November 27,
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.
By 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.
For service information identified in this proposed AD, contact
Boeing Commercial Airplanes, Long Beach Division, 3855 Lakewood
Boulevard, Long Beach, California 90846, Attention: Data and Service
Management, Dept. C1-L5A (D800-0024).
You can examine the contents of this AD docket on the Internet at
http://dms.dot.gov, or in person at the Docket Management Facility,
U.S. Department of Transportation, 400 Seventh Street, SW., room PL-
401, on the plaza level of the Nassif Building, Washington, DC. This
docket number is FAA-2006-26043; the directorate identifier for this
docket is 2005-NM-010-AD.
FOR FURTHER INFORMATION CONTACT: Thomas Phan, Aerospace Engineer,
Systems and Equipment Branch, ANM-130L, FAA, Los Angeles Aircraft
Certification Office, 3960 Paramount Boulevard, Lakewood, California
90712-4137; telephone (562) 627-5342; fax (562) 627-5210.
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 under ADDRESSES. Include ``Docket No. FAA-2006-26043;
Directorate Identifier 2005-NM-010-AD'' in the subject line 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 submitted 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 can review DOT's complete Privacy Act Statement in the
Federal Register published on April 11, 2000 (65 FR 19477-78), or you
can visit http://dms.dot.gov.
Examining the Docket
You can 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 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 DMS receives them.
Discussion
We have received reports of failed power conversion distribution
units (PCDUs). Such failures resulted, by design, in the loss of an
electrical bus (both AC and DC power). Following the loss of the
electrical bus, the flight deck displays took an abnormally long time
to reconfigure, and a strong electrical burning odor was noted in the
flight deck and forward cabin. Investigation revealed a short in the
power supply of the PCDU's generator control unit. The strong
electrical burning odor in the cabin has been attributed to a failed
PCDU on which a short condition can result in overheating of the power
supply T1 transformer. Further, service history has shown that an
intermittent loss of engine N2 speed signal to the PCDU can result in a
bus tie lockout condition and automatic activation of the emergency
power. The loss of an electrical bus due to a failed PCDU could result
in an abnormally long time for all flight deck displays to reconfigure,
and consequent emergency landing.
[[Page 60081]]
Relevant Service Information
We have reviewed Boeing Alert Service Bulletin 717-24A0028,
Revision 1, dated December 20, 2005. The service bulletin describes
procedures for modifying PCDUs having part number 762904E. The
modification involves modifying the printed wiring board (PWB) assembly
A4 and installing new PCDU firmware.
The Boeing service bulletin refers to Hamilton Sundstrand Service
Bulletin 40EGS22P-24-10, dated August 4, 2004, as an additional source
of service information for the modification.
Hamilton Sundstrand Service Bulletin 40EGS22P-24-10 specifies the
concurrent accomplishment of the actions specified in the Hamilton
Sundstrand service bulletins listed in the following table:
Concurrent Service Bulletins
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Hamilton Sundstrand
Actions Service Bulletin Revision level Date
----------------------------------------------------------------------------------------------------------------
Reworking the transformer 40EGS22P-24-3........ Original.............. June 30, 2000.
rectifier unit assembly (TRU).
Reworking the W3 wiring harness
assembly to install direct lead
wires to the TRU.
Adding a ground wire to the TRU
transformer.
Adding an insulated spacer to the
PCDU top cover.
Installing new PCDU 186 firmware.. 40EGS22P-24-4........ Original.............. April 26, 2001.
1..................... January 2, 2002.
Installing new PCDU 186 firmware.. 40EGS22P-24-6........ Original.............. July 25, 2002.
Modifying the top cover of the 40EGS22P-24-7........ Original.............. September 3, 2003.
PCDU.
Modifying PWB assemblies A4 and A5 40EGS22P-24-8........ Original.............. September 4, 2003.
Checking and applying torque seal
to fasteners on the TRU assembly
and to PCDU internal fasteners,
if necessary.
Modifying PWB assembly A4......... 40EGS22P-24-9........ Original.............. November 19, 2003.
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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 exist or develop on other airplanes
of this same type design. Therefore, we are proposing this AD, which
would require identifying the part number of the PCDU and accomplishing
the applicable actions specified in the service information described
previously.
Costs of Compliance
There are about 137 airplanes of the affected design in the
worldwide fleet and 108 U.S.-registered airplanes. The following table
provides the estimated costs for U.S. operators to comply with this
proposed AD.
Estimated Costs for Primary Actions
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Labor rate per Cost per
Boeing Service Bulletin Work hours hour Parts cost airplane
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Part number identification...................... 1 $80 $0 $80
Modification (717-24A0028)...................... 12 80 0 960
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Estimated Costs for Concurrent Actions
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Hamilton Sundstrand Service Labor rate per Cost per
Bulletin Work hours hour Parts cost airplane
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40EGS22P-24-3...................... 6..................... $80 $154, per airplane.... $634
40EGS22P-24-4...................... 3..................... 80 0..................... 240
40EGS22P-24-6...................... 3..................... 80 0..................... 240
40EGS22P-24-7...................... 1 per PCDU............ 80 10 per PCDU, maximum 3 \1\ 110
PCDUs per airplane.
40EGS22P-24-8...................... 10.................... 80 0..................... 800
40EGS22P-24-9...................... 10.................... 80 0..................... 800
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\1\ Maximum.
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
[[Page 60082]]
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. 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 FAA amends Sec. 39.13 by adding the following new
airworthiness directive (AD):
McDonnell Douglas: Docket No. FAA-2006-26043; Directorate Identifier
2005-NM-010-AD.
Comments Due Date
(a) The Federal Aviation Administration (FAA) must receive
comments on this AD action by November 27, 2006.
Affected ADs
(b) None.
Applicability
(c) This AD applies to all McDonnell Douglas Model 717-200
airplanes, certificated in any category.
Unsafe Condition
(d) This AD was prompted by reports of failed power conversion
distribution units (PCDUs), the loss of an electrical bus, and the
presence of a strong electrical burning odor in the flight deck and
forward cabin. We are issuing this AD to prevent the loss of an
electrical bus due to a PCDU failure, which could result in an
abnormally long time for all flight deck displays to reconfigure,
and consequent emergency landing.
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.
Identification of PCDU Part Number
(f) Within 20 months after the effective date of this AD,
inspect the PCDU to determine its part number. A review of airplane
maintenance records is acceptable in lieu of this inspection if the
part number can be conclusively determined from that review.
(1) If the part number is 762904E, do the actions specified in
paragraphs (g) and (h) of this AD.
(2) If the part number is not 762904E, no further work is
required by this AD.
Modification
(g) Within 20 months after the effective date of this AD, modify
the PCDU in accordance with Boeing Alert Service Bulletin 717-
24A0028, Revision 1, dated December 20, 2005. A modification done
before the effective date of this AD in accordance with Boeing Alert
Service Bulletin 717-24A0028, dated November 24, 2004, is acceptable
for compliance with the requirements of this paragraph.
Note 1: Boeing Alert Service Bulletin 717-24A0028 refers to
Hamilton Sundstrand Service Bulletin 40EGS22P-24-10, Revision 1,
dated May 11, 2005, as an additional source of service information
for the modification.
Concurrent Requirements
(h) Before or concurrently with the modification required by
paragraph (g) of this AD, do the applicable actions specified in
Table 1 of this AD.
Table 1.--Concurrent Service Bulletins
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In accordance with Hamilton
Do the following-- Sundstrand Service
Bulletin--
------------------------------------------------------------------------
Rework the transformer rectifier unit 40EGS22P-24-3, dated June
assembly (TRU). 30, 2000.
Rework the W3 wiring harness assembly to
install direct lead wires to the TRU.
Add a ground wire to the TRU transformer.
Add an insulated spacer to the PCDU top
cover.
Install new PCDU 186 firmware.............. 40EGS22P-24-4, Revision 1,
dated January 2, 2002.
Install new PCDU 186 firmware.............. 40EGS22P-24-6, dated July
25, 2002.
Modify the top cover of the PCDU........... 40EGS22P-24-7, dated
September 3, 2003.
Modify printed wiring board (PWB) 40EGS22P-24-8, dated
assemblies A4 and A5. September 4, 2003.
Check and apply torque seal to fasteners on
the TRU assembly and to PCDU internal
fasteners, as applicable.
Modify the PWB assembly A4................. 40EGS22P-24-9, dated
November 19, 2003.
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Credit for Accomplishment of Earlier Service Bulletin
(i) Installation of new PCDU 186 firmware before the effective
date of this AD in accordance with Hamilton Sundstrand Service
Bulletin 40EGS22P-24-4, dated April 26, 2001, is acceptable for
compliance with the corresponding requirements of paragraph (h) of
this AD.
Alternative Methods of Compliance (AMOCs)
(j) The Manager, Los Angeles 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.
[[Page 60083]]
Issued in Renton, Washington, on October 3, 2006.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. E6-16891 Filed 10-11-06; 8:45 am]
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