

[Federal Register: August 28, 2007 (Volume 72, Number 166)]
[Rules and Regulations]               
[Page 49183-49186]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr28au07-19]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-27687; Directorate Identifier 2000-NE-42-AD; 
Amendment 39-15179; AD 2007-07-07R1]
RIN 2120-AA64

 
Airworthiness Directives; General Electric Company CF34-1A, -3A, 
-3A1, -3A2, -3B, and -3B1 Turbofan Engines

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

ACTION: Final rule; request for comments.

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

SUMMARY: The FAA is revising an existing airworthiness directive (AD) 
for General Electric Company (GE) CF34-1A, -3A, -3A1, -3A2, -3B, and -
3B1 turbofan engines. That AD currently requires a one-time inspection 
of certain fan disks for electrical arc-out indications, replacing fan 
disks with electrical arc-out indications, and reducing the life limit 
of certain fan disks. This AD results from a comment received on AD 
2007-07-07, and from recently issued revisions to the applicable GE 
Alert Service Bulletins (ASBs). We are issuing this AD to prevent an 
uncontained fan disk failure and airplane damage.

DATES: Effective September 12, 2007. The Director of the Federal 
Register approved the incorporation by reference of certain 
publications listed in the regulations as of September 12, 2007.
    We must receive any comments on this AD by October 29, 2007.

ADDRESSES: Use one of the following addresses to comment 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: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590.
     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
     Fax: (202) 493-2251.
    You can get the service information identified in this AD from 
General Electric Company via Lockheed Martin Technology Services, 10525 
Chester Road, Suite C, Cincinnati, Ohio 45215; telephone (513) 672-
8400; fax (513) 672-8422.
    The Docket Operations office is located at U.S. Department of 
Transportation, Docket Operations, M-30, West Building Ground Floor, 
Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT: Tara Chaidez, Aerospace Engineer, 
Engine Certification Office, FAA, Engine and Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803; e-mail: 
tara.chaidez@faa.gov; telephone (781) 238-7773; fax (781) 238-7199.


SUPPLEMENTARY INFORMATION: On March 30, 2007, the FAA issued AD 2007-
07-07, Amendment 39-15012 (72 FR 16998, April 6, 2007). That AD 
requires a onetime inspection of certain fan disks for electrical arc-
out indications, replacing fan disks with electrical arc-out 
indications, and reducing the life limit of certain fan disks. That AD 
was the result of a report that in January 2007, a CF34-3B1 turbofan 
engine experienced an uncontained fan disk failure during flight 
operation. That condition, if not corrected, could result in an 
uncontained fan disk failure and airplane damage.

Actions Since AD 2007-07-07 Was Issued

    Since AD 2007-07-07 was issued, we received a comment from Star Air 
A/S, requesting clarification of the compliance requirement in Table C, 
item (ii). We published Table C as follows:

 Table C.--Business Jet Shop-Level Fan Disk Inspection Compliance Times
------------------------------------------------------------------------
             For fan disks                           Inspect
------------------------------------------------------------------------
(i) That have more than 5,500 flight     Within 500 flight hours after
 hours on the effective date of this AD.  the effective date of this AD.
(ii) That have 5,500 or fewer flight     Within accumulating a total of
 hours on the effective date of this AD.  6,000 fan disk operating hours-
                                          since-new, or 5 calendar
                                          years, whichever occurs first.
------------------------------------------------------------------------

    The commenter asks if we intended to state ``within 5 calendar 
years after the effective date of the AD'', or, ``within 5 years-since-
new.'' We intended to state ``within 5 years after the effective date 
of the AD.'' For clarification, we revised Table C as follows:

 Table C.--Business Jet Shop-Level Fan Disk Inspection Compliance Times
------------------------------------------------------------------------
             For fan disks                           Inspect
------------------------------------------------------------------------
(i) That have not had a shop-level       Within 500 flight hours after
 inspection and have more than 5,500      the effective date of this AD.
 flight hours on the effective date of
 this AD.
(ii) That have not had a shop-level      Within accumulating a total of
 inspection and have 5,500 or fewer       6,000 fan disk operating hours-
 flight hours on the effective date of    since-new.
 this AD.

[[Page 49184]]


(iii) That have had a shop-level         Within accumulating an
 inspection and have 5,500 or fewer       additional 6,000 fan disk
 flight hours on the effective date of    operating hours-since-shop-
 this AD.                                 level inspection, or within 5
                                          calendar years from the
                                          effective date of this AD,
                                          whichever occurs first.
------------------------------------------------------------------------

    Also, since that AD was issued, GE issued revisions to the 
applicable ASBs to make document reference updates and accomplishment 
instruction updates. We reference these ASB revisions in this AD 
revision.

Relevant Service Information

    We have reviewed and approved the technical contents of GE ASB No. 
CF34-BJ S/B 72-A0212, Revision 3, dated June 27, 2007, ASB No. CF34-AL 
S/B 72-A0233, Revision 3, dated June 27, 2007, and ASB No. CF34-AL S/B 
72-A0231, Revision 1, dated June 27, 2007. All three ASBs list the 
affected fan disks by serial number and part number. The first two ASBs 
describe procedures for performing fluorescent penetrant inspection 
(FPI), a Tactile and Enhanced Visual (TEV) inspection, and eddy current 
inspection (ECI) for cracks and electrical arc-out defects. The third 
ASB describes procedures for performing an on-wing TEV inspection of 
fan disks for electrical arc-out defects.

FAA's Determination and Requirements of This AD

    The unsafe condition described previously is likely to exist or 
develop on other GE CF34-1A, -3A, -3A1, -3A2, -3B, and -3B1 turbofan 
engines of the same type design. We are issuing this AD to prevent an 
uncontained fan disk failure and airplane damage. This AD requires on-
wing TEV inspection of fan disks for electrical arc-out defects on fan 
disks installed on regional jets within 500 flight hours after the 
effective date of this AD. This AD also requires for all affected fan 
disks shop-level FPI, enhanced TEV, and ECI inspections for cracks and 
electrical arc-out defects. This AD also carries forward from AD 2006-
05-04 the reduced life limit for certain fan disks. You must use the 
service information described previously to perform the actions 
required by this AD.

FAA's Determination of the Effective Date

    Since an unsafe condition exists that requires the immediate 
adoption of this AD, we have found that notice and opportunity for 
public comment before issuing this AD are impracticable, and that good 
cause exists for making this amendment effective in less than 30 days.

Comments Invited

    This AD is a final rule that involves requirements affecting flight 
safety and was not preceded by notice and an opportunity for public 
comment; however, we invite you to send us any written relevant data, 
views, or arguments regarding this AD. Send your comments to an address 
listed under ADDRESSES. Include ``AD Docket No. FAA-2007-27687; 
Directorate Identifier 2000-NE-42-AD'' in the subject line of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of the rule that might 
suggest a need to modify it.
    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 AD. Using the search function of the DMS 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 you may visit 
http://dms.dot.gov.


Examining the AD Docket

    You may examine the AD docket on the Internet at http://dms.dot.gov
; or in person at the Docket Operations office between 9 

a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD 
docket contains this AD, the regulatory evaluation, any comments 
received, and other information. The street address for the Docket 
Operations office (telephone (800) 647-5527) is provided in the 
ADDRESSES section. Comments will be available in the AD docket shortly 
after receipt.

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 AD will not have federalism 
implications under Executive Order 13132. This AD 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.
    For the reasons discussed above, I certify that this AD:
    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 summary of the costs to comply with this AD and 
placed it in the AD Docket. You may get a copy of this summary at the 
address listed under ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

    Under 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:

[[Page 49185]]

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. The FAA amends Sec.  39.13 by removing Amendment 39-15012 (72 FR 
16998, April 6, 2007), and by adding a new airworthiness directive, 
Amendment 39-15179, to read as follows:

2007-07-07R1 General Electric Company: Amendment 39-15179. Docket 
No. FAA-2007-27687; Directorate Identifier 2000-NE-42-AD.

Effective Date

    (a) This airworthiness directive (AD) becomes effective 
September 12, 2007.

Affected ADs

    (b) This AD revises AD 2007-07-07.

Applicability

    (c) This AD applies to General Electric Company (GE) CF34-1A, -
3A, -3A1, -3A2, -3B, and -3B1 turbofan engines, with fan disks part 
numbers (P/Ns) 5921T18G01, 5921T18G09, 5921T18G10, 5921T54G01, 
5922T01G02, 5922T01G04, 5922T01G05, 6020T62G04, 6020T62G05, 
6078T00G01, 6078T57G01, 6078T57G02, 6078T57G03, 6078T57G04, 
6078T57G05, and 6078T57G06 installed. These engines are installed 
on, but not limited to, Bombardier Canadair airplane models CL-600-
2A12, -2B16, and -2B19.

Unsafe Condition

    (d) This AD results from a comment received on AD 2007-07-07, 
and from GE recently issuing revisions to the applicable GE Alert 
Service Bulletins (ASBs). We are issuing this AD to prevent an 
uncontained fan disk failure and airplane damage.

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.

Removal of Certain Fan Disks From Service

    (f) For fan disks listed by P/N and serial number (SN) in the 
following Table A that have fewer than 8,000 cycles-since-new (CSN) 
on the effective date of this AD, replace fan disks before 
accumulating 8,000 CSN:

   Table A.--Fan Disks That Require Removal Based on Blended Callouts
------------------------------------------------------------------------
               Disk part No.                       Disk serial No.
------------------------------------------------------------------------
6078T57G02................................  GAT6306N
6078T00G01................................  GAT3860G
6078T57G02................................  GAT1924L
5922T01G04................................  GAT9599G
6078T57G04................................  GEE05831
6078T57G04................................  GEE06612
6078T57G04................................  GEE06618
6078T57G04................................  GEE06974
6078T57G04................................  GEE06980
6078T57G05................................  GEE143FY
6078T57G05................................  GEE1453G
6078T57G05................................  GEE14452
6078T57G05................................  GEE145NA
6078T57G04................................  GEE08086
6078T57G04................................  GEE09287
6078T57G04................................  GEE09337
6078T57G05................................  GEE12720
6078T57G05................................  GEE14214
6078T57G05................................  GEE142YT
6078T57G05................................  GEE146GT
------------------------------------------------------------------------

    (g) For fan disks listed in Table A of this AD that have 8,000 
CSN or more on the effective date of this AD, replace the disk 
within 15 days after the effective date of this AD.

Inspections of Fan Disks Installed in Regional Jet Airplanes

    (h) For CF34-3A1 and CF34-3B1 turbofan engines installed on 
Bombardier Canadair CL600-2B19 Regional Jet airplanes:

On-Wing Tactile and Enhanced Visual (TEV) Inspection

    (1) On-wing TEV inspect the fan disks listed by P/N and SN in 
Table 1 of GE ASB No. CF34-AL S/B 72-A0231, Revision 1, dated June 
27, 2007, using the compliance times specified in the following 
Table B:

   Table B.--Regional Jet On-wing Fan Disk Inspection Compliance Times
------------------------------------------------------------------------
             For fan disks                           Inspect
------------------------------------------------------------------------
(i) That have not had a shop-level       Within 500 flight hours after
 inspection.                              the effective date of this AD.
(ii) That are marked with an asterisk    Within 500 flight hours after
 in Table 1 of GE ASB No. CF34-AL S/B     the effective date of this AD.
 72-A0231, Revision 1, dated June 27,
 2007.
------------------------------------------------------------------------

    (2) Use paragraphs 3.A. through 3.A.(13) of the Accomplishment 
Instructions of GE ASB No. CF34-AL S/B 72-A0231, Revision 1, dated 
June 27, 2007, to do the inspection.

Shop-Level Inspection

    (3) Within 5,000 flight hours or 5 calendar years after the 
effective date of this AD, whichever occurs first, fluorescent 
penetrant inspect (FPI), TEV inspect, and eddy current inspect (ECI) 
at shop-level for cracks and electrical arc-out defects on the fan 
disks listed by P/N and SN in Table 1 of GE ASB No. CF34-AL S/B 72-
A0233, Revision 3, dated June 27, 2007.
    (4) Use paragraphs 3.A.(1) through 3.A.(6) of the Accomplishment 
Instructions of GE ASB No. CF34-AL S/B 72-A0233, Revision 3, dated 
June 27, 2007, to do the inspections.

Shop-Level Inspection Exemption

    (5) Fan disks are exempt from the shop-level inspection, that 
meet the following criteria:
    (i) Fan disks inspected before the effective date of this AD per 
GE Engine Manual No. SEI-756, Section 72-21-00 (FAN ROTOR ASSEMBLY 
INSPECTION); and
    (ii) That have accumulated no more than 100 cycles since that 
inspection; and
    (iii) That pass the on-wing TEV inspection in paragraph (h)(2) 
of this AD.

Inspection of Fan Disks Installed in Business Jet Airplanes

    (i) For CF34-1A, -3A, -3A1, -3A2, and -3B turbofan engines 
installed on Bombardier Canadair Models CL-600-2A12 (CL-601), CL-
600-2B16 (CL-601-3A), (CL-601-3R), and (CL-604) Business Jet 
airplanes:
    (1) FPI, TEV inspect, and ECI for cracks and electrical arc-out 
defects at shop-level on the fan disks listed by P/N and SN in Table 
1 of GE ASB No. CF34-BJ S/B 72-A0212, Revision 3, dated June 27, 
2007, using the compliance times specified in the following Table C:

 Table C.--Business Jet Shop-level Fan Disk Inspection Compliance Times
------------------------------------------------------------------------
             For fan disks                           Inspect
------------------------------------------------------------------------
(i) That have not had a shop-level       Within 500 flight hours after
 inspection and have more than 5,500      the effective date of this AD.
 flight hours on the effective date of
 this AD.
(ii) That have not had a shop-level      Within accumulating a total of
 inspection and have 5,500 or fewer       6,000 fan disk operating hours-
 flight hours on the effective date of    since-new.
 this AD.

[[Page 49186]]


(iii) That have had a shop-level         Within accumulating an
 inspection and have 5,500 or fewer       additional 6,000 fan disk
 flight hours on the effective date of    operating hours-since-shop-
 this AD.                                 level inspection, or within 5
                                          calendar years from the
                                          effective date of this AD,
                                          whichever occurs first.
------------------------------------------------------------------------

    (2) Use paragraphs 3.A. through 3.A.(10) of the Accomplishment 
Instructions of GE ASB No. CF34-BJ S/B 72-A0212, Revision 3, dated 
June 27, 2007, to do the inspections.

Reporting Requirements

    (j) Under the provisions of the Paperwork Reduction Act of 1980 
(44 U.S.C. 3501 et seq.), the Office of Management and Budget (OMB) 
has approved the information collection requirements contained in 
this AD, and has assigned OMB Control Number 2120-0056.
    (1) Report the results of the on-wing inspections performed in 
paragraph (h)(2) of this AD by following the instructions in 
paragraph 3.A.(14) of the Accomplishment Instructions of GE ASB No. 
CF34-AL S/B 72-A0231, Revision 1, dated June 27, 2007.
    (2) Report the results of the shop-level inspections performed 
in paragraph (h)(4) of this AD by following the instructions in 
paragraph 3.A.(3)(b)11 of the Accomplishment Instructions of GE ASB 
No. CF34-AL S/B 72-A0233, Revision 3, dated June 27, 2007.
    (3) Report the results of the shop-level inspections performed 
in paragraph (i)(2) of this AD by following the instructions in 
paragraph 3.A.(3)(b)11 of the Accomplishment Instructions of GE ASB 
No. CF34-AL S/B 72-A0212, Revision 3, dated June 27, 2007.

Previous Credit

    (k) Credit is allowed for:
    (1) Fan disks previously shop-level inspected before the 
effective date of this AD using GE ASB No. CF34-AL S/B 72-A0233, 
dated March 7, 2007, Revision 1, dated March 16, 2007, or Revision 
2, dated March 22, 2007; and GE ASB No. CF34-BJ S/B 72-A0212, dated 
March 7, 2007, Revision 1, dated March 16, 2007, or Revision 2, 
dated March 22, 2007.
    (2) Fan disks previously on-wing TEV inspected before the 
effective date of this AD using GE ASB No. CF34-AL S/B 72-A0231, 
dated March 7, 2007.

Alternative Methods of Compliance

    (l) The Manager, Engine Certification Office, has the authority 
to approve alternative methods of compliance for this AD if 
requested using the procedures found in 14 CFR 39.19.

Related Information

    (m) Emergency AD 2007-04-51 and AD 2007-05-16 also pertain to 
the subject of this AD.

Material Incorporated by Reference

    (n) You must use the General Electric Company Alert Service 
Bulletins listed in Table D of this AD to perform the inspections 
required by this AD. The Director of the Federal Register approved 
the incorporation by reference of the documents listed in Table D of 
this AD in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. You 
can get a copy from General Electric Company via Lockheed Martin 
Technology Services, 10525 Chester Road, Suite C, Cincinnati, Ohio 
45215; telephone (513) 672-8400; fax (513) 672-8422. You can review 
copies at the FAA, New England Region, 12 New England Executive 
Park, Burlington, MA; or at the National Archives and Records 
Administration (NARA). For information on the availability of this 
material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html
.


                                      Table D.--Incorporation by Reference
----------------------------------------------------------------------------------------------------------------
        Alert service bulletin no.                Page number         Revision                Date
----------------------------------------------------------------------------------------------------------------
CF34-AL S/B 72-A0231.....................  All.....................          1  June 27, 2007.
Total Pages: 94..........................
CF34-AL S/B 72-A0233.....................  All.....................          3  June 27, 2007.
Total Pages: 92..........................
CF34-BJ S/B 72-A0212.....................  All.....................          3  June 27, 2007.
Total Pages: 96..........................
----------------------------------------------------------------------------------------------------------------


    Issued in Burlington, Massachusetts, on August 16, 2007.
Peter A. White,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
 [FR Doc. E7-16554 Filed 8-27-07; 8:45 am]

BILLING CODE 4910-13-P
