Airworthiness Directives; Pratt & Whitney JT9D-7R4 Turbofan Engines, 9276-9281 [E7-3561]

Download as PDF 9276 Federal Register / Vol. 72, No. 40 / Thursday, March 1, 2007 / Proposed Rules calculated, if reliable or conservative aerodynamic data is used. Power, as specified in § 25.175(b)(1)(iv), is assumed until recovery is made, at which time power reduction and the use of pilot controlled drag devices may be used. (b) From a speed below VC/MC with power to maintain stabilized level flight at this speed, the airplane is upset so as to accelerate through VC/MC at a flight path 15 degrees below the initial path— or at the steepest nose down attitude that the system will permit with full control authority if less than 15 degrees. Notice of proposed rulemaking (NPRM). ACTION: 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 https:// 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 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 https:// dms.dot.gov. Federal Aviation Administration SUMMARY: The FAA proposes to supersede an existing airworthiness directive (AD) for Pratt & Whitney (PW) JT9D–7R4 turbofan engines. That AD currently requires inspection of the blade root thickness of 1st stage fan blades identified by part number (P/N) and serial number (SN) in the AD. This proposed AD would require the same actions but would correct 12 P/Ns, add 10 part SNs, and add the definition of next fan blade exposure to the compliance section. This proposed AD results from the discovery of inaccurate part quantity, part numbers, and serial numbers used in AD 2005–26–09. We are proposing this AD to prevent 1st stage fan blade fracture and uncontained engine failure, resulting in possible damage to the airplane. DATES: We must receive any comments on this proposed AD by April 30, 2007. ADDRESSES: Use one of the following addresses to comment on this proposed AD. • DOT Docket Web site: Go to https://dms.dot.gov and follow the instructions for sending your comments electronically. • Government-wide rulemaking Web site: Go to https://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– 0001. • 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 FURTHER INFORMATION CONTACT: Kevin Donovan, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803–5299; telephone (781) 238–7743, fax (781) 238–7199. SUPPLEMENTARY INFORMATION: 14 CFR Part 39 Comments Invited Actions Since AD 2005–26–09 Was Issued We invite you to send any written relevant data, views, or arguments regarding this proposal. Send your comments to an address listed under ADDRESSES. Include ‘‘Docket No. FAA– 2005–23072; Directorate Identifier 2005–NE–38–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 Since AD 2005–26–09 was issued, we received comments on the AD requesting clarification. We considered those requests and have changed the compliance section in this proposed AD for clarification. We also found and corrected 12 incorrect P/Ns, and added 10 part SNs of affected 1st stage fan blades to Table 1 of this proposed AD. The comments and affected P/Ns and SNs are also discussed below. Note: The pilot’s controls may be in the neutral position after reaching VC/MC and before recovery is initiated. (c) Recovery may be initiated three seconds after operation of high speed warning system by application of a load of 1.5g (0.5 acceleration increment) or such greater load factor that is automatically applied by the system with the pilot’s pitch control neutral. Power may be reduced simultaneously. All other means of decelerating the airplane, the use of which is authorized up to the highest speed reached in the maneuver, may be used. The interval between successive pilot actions must not be less than one second. (d) The applicant must also demonstrate that the design dive speed, established above, will not be exceeded during pilot-induced or gust-induced upsets in non-symmetric attitudes. (e) The occurrence of any failure condition that would reduce the capability of the overspeed protection system must be improbable (less than 10–5 per flight hour). Issued in Renton, Washington, on February 23, 2007. Ali Bahrami, Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. E7–3582 Filed 2–28–07; 8:45 am] BILLING CODE 4910–13–P DEPARTMENT OF TRANSPORTATION rmajette on PROD1PC67 with PROPOSALS [Docket No. FAA–2005–23072; Directorate Identifier 2005–NE–38–AD] RIN 2120–AA64 Airworthiness Directives; Pratt & Whitney JT9D–7R4 Turbofan Engines Federal Aviation Administration (FAA), Department of Transportation (DOT). AGENCY: VerDate Aug<31>2005 14:56 Feb 28, 2007 Jkt 211001 PO 00000 Frm 00004 Fmt 4702 Sfmt 4702 Examining the AD Docket You may examine the docket that contains the proposal, any comments received and any final disposition in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Office (telephone (800) 647–5227) is located on the plaza level of the Department of Transportation Nassif Building at the street address stated in ADDRESSES. Comments will be available in the AD docket shortly after the DMS receives them. Discussion On December 16, 2005, the FAA issued AD 2005–26–09, Amendment 39–14430 (70 FR 76381, December 27, 2005). That AD requires inspection of the blade root thickness of 1st stage fan blades identified by P/N and SN. That AD was the result of a report of a repair station that created an unapproved repair on 1st stage fan blades. That condition, if not corrected, could result in 1st stage fan blade fracture and uncontained engine failure, resulting in possible damage to the airplane. E:\FR\FM\01MRP1.SGM 01MRP1 9277 Federal Register / Vol. 72, No. 40 / Thursday, March 1, 2007 / Proposed Rules Request To Clarify ‘‘At the Next 1st Stage Fan Blade Exposure’’ Two air carriers request that we clarify ‘‘at the next 1st stage fan blade exposure,’’ to prevent any in-service disruptions or delays. The commenter further states that the 1st stage fan blades can be exposed when: • Some 1st stage fan blades are replaced due to in-service foreign object damage; • A 1st stage fan hub is replaced and the same 1st stage fan blades are reused; and • At shop visit when 1st stage fan blades are removed from the fan hub for cause or work scope. We agree with adding a paragraph to the proposed AD which defines next 1st stage fan blade exposure. We have defined it as when any 1st stage fan blade is removed from the engine; or when the 1st stage fan hub is removed from the engine. rmajette on PROD1PC67 with PROPOSALS Suggestion To Report When Finding Affected 1st Stage Fan Blades Air Canada suggests that operators finding any affected 1st stage fan blades should report back to the FAA. The commenter states that by requiring this reporting, all 520 of the blades can then be accounted for, and the FAA can close the AD. The commenter is also concerned that if some blades cannot be accounted for, such as blades already scrapped, misplaced, or shelved, then the AD will never be closed, and operators will be forced to verify the AD indefinitely at every 1st stage fan blade installation. We do not agree. This proposed AD requires a onetime inspection for a specific population of 1st stage fan blades. If an operator has inspected and verified a certain set of 1st stage fan blades in accordance with the proposed AD, then at the next 1st stage fan blade exposure, only replacement blades that are listed in Table 1 of the proposed AD will require inspection and verification. Request To Clarify or Remove Paragraph (e) Air Canada states that compliance paragraph (e) mentions that the AD must be performed within the compliance times specified, but there are no times specified. The commenter requests this instruction be removed or clarified. We partially agree. We revised the compliance times for clarification in the proposed AD. Comment That ‘‘At Exposure’’ Limit Is Not a Practical Limit ABX AIR claims that the ‘‘at exposure’’ limit in the AD is not VerDate Aug<31>2005 14:56 Feb 28, 2007 Jkt 211001 practical. They said that ‘‘at exposure’’ will require the operators to set up a special inspection schedule to accomplish this onetime inspection which is not suitable for fleet operators. We partially agree. Inspecting the affected parts at the next 1st stage fan blade exposure is sufficient. It is not necessary for operators to set up a special inspection schedule since this inspection does not impact the FAAapproved maintenance program procedures. However, for clarification, we added a definition for ‘‘next first stage fan blade exposure’’ to the proposed AD. Request To Clarify ‘‘Before Installing the 1st Stage Fan Blades’’ ABX AIR requests that we clarify ‘‘before installing the 1st stage fan blades’’ in paragraph (f). ABX believes the AD should contain a concise clarifying statement such as: ‘‘After the active date of this AD, no person may install, on any airplane, any blade listed in Table 1 of this AD unless the actions of this AD have already been accomplished.’’ We agree. We added a prohibition statement that states that after the effective date of this (proposed) AD, do not install any 1st stage fan blades listed in Table 1 of this AD on any airplane, unless the actions of this AD have been done to the 1st stage fan blades. P/Ns Corrected, and P/Ns and SNs Added Since we issued AD 2005–26–09, we found and corrected 12 incorrect P/Ns, and added 10 part SNs of affected 1st stage fan blades in Table 1 of this proposed AD. The corrected numbers are as follows: Incorrect P/Ns 5001341–023 5001341–024 5001341–025 5001341–026 5001341–027 5001341–028 5001341–029 5001341–030 5001341–031 5001341–032 5001341–033 5001341–034 .... .... .... .... .... .... .... .... .... .... .... .... Corrected P/Ns SNs 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 JW2313 JW2498 JW2541 JW2560 JW2589 JW2639 JW2760 JW2792 MO579 MG2825 MG5477 ND5917 The added part SNs are as follows: Added SNs PNs 5001341–022 ........................ 5001341–022 ........................ 5001341–022 ........................ 831021–003 .......................... PO 00000 Frm 00005 Fmt 4702 Sfmt 4702 JW4713 MG6743 ND6924 ND9177 PNs Added SNs 831021–003 .......................... 831021–003 .......................... 831021–003 .......................... 831021–003 .......................... 804121 .................................. 804121 .................................. ND9496 NS7894 NS8559 NS9072 PX3805 PX4266 Conclusion We have carefully reviewed the available data, including the comments received, and determined that air safety and the public interest require proposing this AD with the changes described previously. We have determined that these changes will neither increase the economic burden on any operator nor increase the scope of the proposed AD. 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 products of this same type design. For that reason, we are proposing this AD, which would require: • Checking the 1st stage fan blade for a circled, letter I, on the approved marking area of the outboard side of the blade platform. If the blade has this marking, no further action is required. • Removing 1st stage fan blades without a circled, letter I, on the approved marking area of the outboard side of the blade platform if installed; and • Inspecting the 1st stage fan blade root thickness; and • Returning to service 1st stage fan blades that pass the inspection, after properly marking the blade. Costs of Compliance We estimate that this proposed AD would affect 531 1st stage fan blades installed on JT9D–7R4 turbofan engines installed on airplanes of U.S. registry. We also estimate that it would take about 0.5 work-hour per 1st stage fan blade to perform the proposed actions, and that the average labor rate is $80 per work-hour. Based on these figures, we estimate the total cost of the proposed AD to U.S. operators to be $21,240. 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. E:\FR\FM\01MRP1.SGM 01MRP1 9278 Federal Register / Vol. 72, No. 40 / Thursday, March 1, 2007 / Proposed Rules 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 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. Would 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 Under the authority delegated to me by the Administrator, the Federal Aviation Administration 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: rmajette on PROD1PC67 with PROPOSALS Authority: 49 U.S.C. 106(g), 40113, 44701. § 39.13 [Amended] 2. The FAA amends § 39.13 by removing Amendment 39–14430 (70 FR 76381, December 27, 2005), and by adding a new airworthiness directive to read as follows: VerDate Aug<31>2005 14:56 Feb 28, 2007 Jkt 211001 Pratt & Whitney: Docket No. FAA–2005– 23072; Directorate Identifier 2005–NE– 38–AD. Comments Due Date (a) The Federal Aviation Administration (FAA) must receive comments on this airworthiness directive (AD) action by April 30, 2007. Affected ADs (b) This AD supersedes AD 2005–26–09. Applicability (c) This AD applies to Pratt & Whitney (PW) JT9D–7R4 turbofan engines. These engines are installed on, but not limited to, Airbus A300 and A310, and Boeing 747 and 767 airplanes. Unsafe Condition (d) This AD results from the discovery of inaccurate part quantity, part numbers, and serial numbers used in AD 2005–26–09. We are issuing this AD to prevent 1st stage fan blade fracture and uncontained engine failure, resulting in possible damage to the airplane. 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. (f) For 1st stage fan blades that are listed by part number (P/N) and serial number (SN) in Table 1 of this AD, do the following: TABLE 1.—AFFECTED 1ST STAGE FAN BLADES P/Ns 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 5001341–022 PO 00000 Frm 00006 SNs ................................ ................................ ................................ ................................ ................................ ................................ ................................ ................................ ................................ ................................ ................................ ................................ ................................ ................................ ................................ ................................ ................................ ................................ ................................ ................................ ................................ ................................ ................................ ................................ ................................ ................................ ................................ ................................ ................................ ................................ ................................ ................................ ................................ Fmt 4702 Sfmt 4702 JW2804 JW0354 ND5746 ND5770 JW3992 ND8615 JW0442 JW2317 ND8631 ND8635 JW4624 NE0394 NE0153 NN8054 JW4693 ND7304 MG6108 MG5862 MG5619 NE0308 NE0200 MG6797 JW0230 ND5652 ND5775 JW0251 ND5719 JW0248 ND5785 ND5676 ND5661 JW0265 ND5699 TABLE 1.—AFFECTED 1ST STAGE FAN BLADES—Continued P/Ns SNs 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... ND5767 JW0259 ND5680 ND5749 JW0235 ND5776 ND8580 MG6039 ND9127 JW4287 JW0262 JW0445 JW4665 MG5901 NE0303 ND8703 JW4574 JW4286 JW4491 JW4630 JW4391 MG6550 MG6776 JW4586 JW0352 JW4261 MG6135 JW4685 MG6772 MG6793 MG7111 ND8618 JW0644 JW4631 JW4651 JW0234 JW4646 NN9016 VJ3393 PX3694 RK9168 PX5023 VJ3324 VJ3504 NN9115 NN8936 PX3816 VJ3412 RK9163 VJ3447 RK9230 RK9109 PX4627 RK8990 SP9459 RK8656 NN8933 VJ3444 ND5864 NN9020 RK8905 SR1733 NN9047 PX3692 PX3786 NN9025 NN9007 RK9100 VJ3399 PX4970 PX5013 E:\FR\FM\01MRP1.SGM 01MRP1 Federal Register / Vol. 72, No. 40 / Thursday, March 1, 2007 / Proposed Rules TABLE 1.—AFFECTED 1ST STAGE FAN BLADES—Continued rmajette on PROD1PC67 with PROPOSALS P/Ns SNs 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. VerDate Aug<31>2005 14:56 Feb 28, 2007 TABLE 1.—AFFECTED 1ST STAGE FAN BLADES—Continued RK8904 NN8986 NN8829 VJ3459 RK9143 VJ3414 NN9028 SP1557 PX5003 PX5042 VJ3475 ND7330 PX3714 NS8913 ND6512 ND6941 ND9576 NS7555 NS8286 NS7447 ND6488 ND8296 ND6956 ND7879 ND6509 ND9814 NN7331 ND6991 ND6894 NS6413 ND7344 ND6947 NN8732 ND8536 ND6946 ND6723 ND9294 ND9290 ND6013 ND8937 NS7160 NS6435 NS6591 ND9558 NS8479 NS9382 ND8965 ND9837 ND5959 NS6491 NS9072 ND9625 ND6714 ND6820 ND8972 NE0286 NE0347 ND8010 ND8956 ND9535 ND9831 NE0227 ND8283 ND9730 NN7656 NS7775 ND9815 ND6135 NS8491 NS6395 NS8584 Jkt 211001 P/Ns 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 PO 00000 Frm 00007 Fmt 4702 TABLE 1.—AFFECTED 1ST STAGE FAN BLADES—Continued SNs .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. Sfmt 4702 NN7272 MG7159 NS6592 ND7862 ND6684 NN7744 ND7480 ND7873 ND6827 ND6576 ND9261 NS8686 ND9052 ND6897 ND6565 NN8966 PX3707 NS7031 ND6584 ND9883 NS6535 ND7852 ND9662 ND7871 JW0106 ND8305 NS6409 NE0442 ND9095 ND9302 ND9023 ND8009 ND8477 ND7492 ND8776 ND6524 ND6704 ND8911 ND8789 ND8798 ND6407 ND7668 ND9179 NE0421 ND6513 ND6744 ND7654 ND7870 ND9759 ND6561 ND5826 ND6031 ND8714 ND8872 ND6678 ND6629 ND8995 NE0302 ND6405 NS8300 NS8769 NS7147 ND6649 ND7766 NS7864 NS8734 ND6677 NS7911 ND8205 ND8804 ND6639 9279 P/Ns 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 831021–003 E:\FR\FM\01MRP1.SGM .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. .................................. 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NS7919 NS7907 ND6583 NN7420 ND7746 ND8187 NN8999 ND6043 ND7880 NN7175 ND9816 ND8174 ND6045 NS7562 JW0075 ND6848 ND8531 ND6311 ND8144 ND5798 ND8113 ND9642 ND7436 ND9054 ND9683 ND5991 ND6026 ND6616 ND6530 NE0374 ND6364 ND7718 ND6473 ND6436 ND6887 ND6518 ND6479 NS6330 ND7264 ND8151 ND6562 NS8776 ND6519 ND7659 NS9049 NS6861 ND9571 ND9346 ND6501 NS8505 9280 Federal Register / Vol. 72, No. 40 / Thursday, March 1, 2007 / Proposed Rules TABLE 1.—AFFECTED 1ST STAGE FAN BLADES—Continued TABLE 1.—AFFECTED 1ST STAGE FAN BLADES—Continued TABLE 1.—AFFECTED 1ST STAGE FAN BLADES—Continued rmajette on PROD1PC67 with PROPOSALS P/Ns SNs P/Ns SNs P/Ns SNs 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ ND9338 ND9775 ND6485 ND7165 ND9371 ND9537 NS7889 ND7877 ND8670 ND9032 ND8781 ND8604 ND9329 ND9110 ND5997 ND6027 ND9589 ND6575 ND6592 ND6463 NS8583 NS8590 NS8567 NS6795 NS7110 NS6587 NS6404 ND6486 JW0942 ND9231 JW4812 ND6555 M1375 MG6627 MG6794 ND9399 NE0084 MG6252 ND7422 ND7043 MG5722 MG5918 ND6984 M0839 M0922 M0938 M1117 M0307 JW3871 M1125 M1149 JW2681 M0270 M1120 M0205 AE9352 JW3492 ND6148 ND8907 M1235 MG5585 ND8436 MG5696 ND8704 JW2284 JW2313 JW2498 JW2541 JW2560 JW2589 JW2639 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... JW2760 JW2792 M0579 MG2825 MG5477 ND5917 JW1976 JW2653 JW2608 JW2727 JW2764 JW2265 JW2474 JW2396 JW3554 JW2667 MG2302 MG3972 JW3930 ND6749 M1172 JW2104 JW2519 JW2640 JW2517 JW2663 JW2823 M0536 JW2725 MG5917 JW0681 JW0711 JW0740 JW0807 JW1089 JW1362 JW2065 MG2434 MG2846 JW0806 NN9854 NN9024 NN9032 PX5029 NN9050 NS8242 NS8260 PX4273 PX4378 RL0857 RX8763 NS8331 NN9824 MG6979 MG7023 MG7055 RK8914 RL0023 PX4328 RK9008 TG1506 KK8226 MG2604 NS6691 RK8968 NN9917 RK7824 M1343 NS6559 NS7767 NE0363 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 804121 .......................................... 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 5001341–022 ................................ 5001341–022 ................................ 5001341–022 ................................ 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 831021–003 .................................. 804121 .......................................... PX3771 NN9972 RL0460 RK8310 SR2115 TG2826 PX5018 PX5002 ND7627 ND6890 ND7461 ND9616 NE0413 NS8825 NS6350 NS7168 NS7705 NS7848 ND9128 ND9541 ND9671 ND9684 NE0277 NE0384 NE0396 ND6421 ND6599 ND6614 ND7847 ND8346 ND8853 ND8915 NS8719 NS8838 NT0169 NS9584 ND6445 ND6834 ND7467 ND8887 ND6520 NS8611 NS7640 NN7037 NN7590 NN8120 NN8573 NN9719 NS8784 TB6B367 NN9557 NN9710 NS8374 NS8770 NS9022 NS8416 NS6474 ND8912 NT0108 NS8836 NN8310 NS8559 JW4713 MG6743 ND6924 ND9177 ND9496 NS7894 NS8559 NS9072 PX3805 VerDate Aug<31>2005 14:56 Feb 28, 2007 Jkt 211001 PO 00000 Frm 00008 Fmt 4702 Sfmt 4702 E:\FR\FM\01MRP1.SGM 01MRP1 Federal Register / Vol. 72, No. 40 / Thursday, March 1, 2007 / Proposed Rules TABLE 1.—AFFECTED 1ST STAGE FAN BLADES—Continued P/Ns SNs 804121 .......................................... PX4266 Issued in Burlington, Massachusetts, on February 23, 2007. Peter A. White, Acting Manager, Engine and Propeller Directorate, Aircraft Certification Service. [FR Doc. E7–3561 Filed 2–28–07; 8:45 am] BILLING CODE 4910–13–P For Engines Installed on an Airplane (1) For engines installed on an airplane with affected 1st stage fan blades installed, perform the actions in paragraphs (f)(3) through (f)(6)(ii) of this AD at the next 1st stage fan blade exposure. DEPARTMENT OF ENERGY Federal Energy Regulatory Commission For Engines Not Installed on an Airplane, or, for Affected 1st Stage Fan Blades Not Installed in an Engine 18 CFR Chapter I (2) For engines not installed on an airplane with affected 1st stage fan blades installed, or, for affected 1st stage fan blades not installed in an engine, paragraph (h) of this AD applies. Preliminary Permits for Wave, Current, and Instream New Technology Hydropower Projects February 15, 2007. 1st Stage Fan Blade Check (3) Check the 1st stage fan blade for a circled, letter I, on the approved marking area of the outboard side of the blade platform. If the blade has this marking, no further action is required. (4) Remove 1st stage fan blades without a circled, letter I, on the approved marking area of the outboard side of the blade platform, if installed. (5) Inspect the 1st stage fan blade root thickness. You can find information on inspecting the blade root thickness in PW Engine Manual Section 72–31–02, Inspect-01, and Repair-23. (6) For 1st stage fan blades that pass the inspection referenced in paragraph (f)(5) of this AD: (i) Vibropeen the letter I and a circle around that letter, on the approved marking area of the outboard side of the blade platform. You can find information on approved blade marking in the JT9D–7R4 Engine Manual, Section 72–31–02, Typical Repair–13, Mark Repair Codes. (ii) Return the 1st stage fan blades to service. Definition (g) For the purposes of paragraph (f)(1) of this AD, next 1st stage fan blade exposure is: (1) When any 1st stage fan blade is removed from the engine; or (2) When the 1st stage fan hub is removed from the engine. rmajette on PROD1PC67 with PROPOSALS Prohibited Installation (h) After the effective date of this AD, do not install any 1st stage fan blades listed in Table 1 of this AD on any airplane, unless the actions of this AD have been done to the 1st stage fan blades. Alternative Methods of Compliance (i) 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 (j) None. VerDate Aug<31>2005 14:56 Feb 28, 2007 [Docket No. RM07–08–000] Jkt 211001 Federal Energy Regulatory Commission, DOE. ACTION: Notice of Inquiry (NOI) and Interim Statement of Policy. AGENCY: SUMMARY: The Federal Energy Regulatory Commission (Commission) is inviting comments on its procedures with respect to the treatment of preliminary permits under Part I of the Federal Power Act for wave, current, and instream new technology hydropower projects. DATES: Comments on this NOI are due on April 30, 2007. ADDRESSES: You may submit comments identified by Docket No. RM07–8–000, by one of the following methods: • Agency Web Site: https://ferc.gov. Follow the instructions for submitting comments via the eFiling link found in the Comment Procedures Section of the preamble. • Mail: Commenters unable to file comments electronically must mail or hand deliver an original and 14 copies of their comments to the Federal Energy Regulatory Commission, Office of the Secretary, 888 First Street, NE., Washington, DC 20426. Please refer to the Comment Procedures Section of the preamble for additional information on how to file paper comments. FOR FURTHER INFORMATION CONTACT: William Guey-Lee, Office of Energy Projects, Federal Energy Regulatory Commission, 888 First Street, NE., Washington, DC 20426, (202) 502– 6064. Merrill Hathaway, (Legal Information), Office of General Counsel—Energy Projects, Federal Energy Regulatory Commission, 888 First Street, NE., Washington, DC 20426, (202) 5028825. SUPPLEMENTARY INFORMATION: PO 00000 Frm 00009 Fmt 4702 Sfmt 4702 9281 Introduction 1. The Federal Energy Regulatory Commission (Commission) is issuing this Notice of Inquiry to seek comments on how it should treat applications for preliminary permits to study hydropower projects involving proposals to utilize wave, current, and instream new technology methods to develop hydropower.1 The Commission is also seeking comments on how it should oversee any such permits during their terms. Finally, the Commission also sets an interim policy pending the outcome of this proceeding. 2. The Commission has seen increasing interest in new hydroelectric technologies that would utilize ocean waves, tides, and currents from freeflowing rivers, as evidenced by a surge in applications for preliminary permits to study such projects. Commission staff has issued 11 preliminary permits for projects of this type; three are for proposed tidal energy projects (in New York, Washington, and California), and eight are for proposed ocean current energy projects (off the coast of Florida). Over 40 preliminary permit applications for ocean projects are currently pending before the Commission, all of which have been filed since March 2006. 3. These new technologies have significant potential: it has been estimated that the potential for wave and current power could be over 350terawatt hours per year, which would more than double current hydropower production.2 The Commission anticipates further exploration of how these technologies can fit within the national energy infrastructure in terms of the amount of potential energy that can be developed, its reliability, environmental and safety implications, and its commercial viability. The Commission wants to reduce regulatory barriers to the development of new technologies, where possible, and has exhibited the maximum flexibility permitted by law in regulating these projects.3 1 There are a variety of technologies in various stages of development to produce electric power using ocean currents, tides, and wave action, rather than the traditional hydropower model involving hydraulic head developed by use of a dam or other diversion structure. For purposes of this notice of inquiry, the Commission refers to these newer forms of technology as ‘‘wave, current, and instream new technology’’ or simply ‘‘new technology.’’ However, the Commission is using the terms as shorthand, and is not attempting to define or limit the scope of these technologies. 2 See Hydroelectric Infrastructure Technical Conference, Docket No. AD06–13–000 (December 6, 2006), transcript at 12; 22 (testimony of George Hagerman). 3 For example, in Verdant, Power, LLC, 111 FERC ¶61,024, on reh’g, 112 FERC ¶61,143 (2005), the E:\FR\FM\01MRP1.SGM Continued 01MRP1

Agencies

[Federal Register Volume 72, Number 40 (Thursday, March 1, 2007)]
[Proposed Rules]
[Pages 9276-9281]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E7-3561]


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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2005-23072; Directorate Identifier 2005-NE-38-AD]
RIN 2120-AA64


Airworthiness Directives; Pratt & Whitney JT9D-7R4 Turbofan 
Engines

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

ACTION: Notice of proposed rulemaking (NPRM).

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

SUMMARY: The FAA proposes to supersede an existing airworthiness 
directive (AD) for Pratt & Whitney (PW) JT9D-7R4 turbofan engines. That 
AD currently requires inspection of the blade root thickness of 1st 
stage fan blades identified by part number (P/N) and serial number (SN) 
in the AD. This proposed AD would require the same actions but would 
correct 12 P/Ns, add 10 part SNs, and add the definition of next fan 
blade exposure to the compliance section. This proposed AD results from 
the discovery of inaccurate part quantity, part numbers, and serial 
numbers used in AD 2005-26-09. We are proposing this AD to prevent 1st 
stage fan blade fracture and uncontained engine failure, resulting in 
possible damage to the airplane.

DATES: We must receive any comments on this proposed AD by April 30, 
2007.

ADDRESSES: Use one of the following addresses to comment on this 
proposed AD.
     DOT Docket Web site: Go to https://dms.dot.gov and follow 
the instructions for sending your comments electronically.
     Government-wide rulemaking Web site: Go to https://
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 20590-0001.
     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 FURTHER INFORMATION CONTACT: Kevin Donovan, Aerospace Engineer, 
Engine Certification Office, FAA, Engine and Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803-5299; telephone (781) 
238-7743, fax (781) 238-7199.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments regarding this proposal. Send your comments to an address 
listed under ADDRESSES. Include ``Docket No. FAA-2005-23072; 
Directorate Identifier 2005-NE-38-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 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 https://
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 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 https://dms.dot.gov.

Examining the AD Docket

    You may examine the docket that contains the proposal, any comments 
received and any final disposition in person at the Docket Management 
Facility between 9 a.m. and 5 p.m., Monday through Friday, except 
Federal holidays. The Docket Office (telephone (800) 647-5227) is 
located on the plaza level of the Department of Transportation Nassif 
Building at the street address stated in ADDRESSES. Comments will be 
available in the AD docket shortly after the DMS receives them.

Discussion

    On December 16, 2005, the FAA issued AD 2005-26-09, Amendment 39-
14430 (70 FR 76381, December 27, 2005). That AD requires inspection of 
the blade root thickness of 1st stage fan blades identified by P/N and 
SN. That AD was the result of a report of a repair station that created 
an unapproved repair on 1st stage fan blades. That condition, if not 
corrected, could result in 1st stage fan blade fracture and uncontained 
engine failure, resulting in possible damage to the airplane.

Actions Since AD 2005-26-09 Was Issued

    Since AD 2005-26-09 was issued, we received comments on the AD 
requesting clarification. We considered those requests and have changed 
the compliance section in this proposed AD for clarification. We also 
found and corrected 12 incorrect P/Ns, and added 10 part SNs of 
affected 1st stage fan blades to Table 1 of this proposed AD. The 
comments and affected P/Ns and SNs are also discussed below.

[[Page 9277]]

Request To Clarify ``At the Next 1st Stage Fan Blade Exposure''

    Two air carriers request that we clarify ``at the next 1st stage 
fan blade exposure,'' to prevent any in-service disruptions or delays. 
The commenter further states that the 1st stage fan blades can be 
exposed when:
     Some 1st stage fan blades are replaced due to in-service 
foreign object damage;
     A 1st stage fan hub is replaced and the same 1st stage fan 
blades are reused; and
     At shop visit when 1st stage fan blades are removed from 
the fan hub for cause or work scope.
    We agree with adding a paragraph to the proposed AD which defines 
next 1st stage fan blade exposure. We have defined it as when any 1st 
stage fan blade is removed from the engine; or when the 1st stage fan 
hub is removed from the engine.

Suggestion To Report When Finding Affected 1st Stage Fan Blades

    Air Canada suggests that operators finding any affected 1st stage 
fan blades should report back to the FAA. The commenter states that by 
requiring this reporting, all 520 of the blades can then be accounted 
for, and the FAA can close the AD. The commenter is also concerned that 
if some blades cannot be accounted for, such as blades already 
scrapped, misplaced, or shelved, then the AD will never be closed, and 
operators will be forced to verify the AD indefinitely at every 1st 
stage fan blade installation.
    We do not agree. This proposed AD requires a onetime inspection for 
a specific population of 1st stage fan blades. If an operator has 
inspected and verified a certain set of 1st stage fan blades in 
accordance with the proposed AD, then at the next 1st stage fan blade 
exposure, only replacement blades that are listed in Table 1 of the 
proposed AD will require inspection and verification.

Request To Clarify or Remove Paragraph (e)

    Air Canada states that compliance paragraph (e) mentions that the 
AD must be performed within the compliance times specified, but there 
are no times specified. The commenter requests this instruction be 
removed or clarified.
    We partially agree. We revised the compliance times for 
clarification in the proposed AD.

Comment That ``At Exposure'' Limit Is Not a Practical Limit

    ABX AIR claims that the ``at exposure'' limit in the AD is not 
practical. They said that ``at exposure'' will require the operators to 
set up a special inspection schedule to accomplish this onetime 
inspection which is not suitable for fleet operators.
    We partially agree. Inspecting the affected parts at the next 1st 
stage fan blade exposure is sufficient. It is not necessary for 
operators to set up a special inspection schedule since this inspection 
does not impact the FAA-approved maintenance program procedures. 
However, for clarification, we added a definition for ``next first 
stage fan blade exposure'' to the proposed AD.

Request To Clarify ``Before Installing the 1st Stage Fan Blades''

    ABX AIR requests that we clarify ``before installing the 1st stage 
fan blades'' in paragraph (f). ABX believes the AD should contain a 
concise clarifying statement such as: ``After the active date of this 
AD, no person may install, on any airplane, any blade listed in Table 1 
of this AD unless the actions of this AD have already been 
accomplished.''
    We agree. We added a prohibition statement that states that after 
the effective date of this (proposed) AD, do not install any 1st stage 
fan blades listed in Table 1 of this AD on any airplane, unless the 
actions of this AD have been done to the 1st stage fan blades.

P/Ns Corrected, and P/Ns and SNs Added

    Since we issued AD 2005-26-09, we found and corrected 12 incorrect 
P/Ns, and added 10 part SNs of affected 1st stage fan blades in Table 1 
of this proposed AD. The corrected numbers are as follows:

------------------------------------------------------------------------
                                       Corrected  P/
           Incorrect P/Ns                   Ns                SNs
------------------------------------------------------------------------
5001341-023.........................     5001341-022  JW2313
5001341-024.........................     5001341-022  JW2498
5001341-025.........................     5001341-022  JW2541
5001341-026.........................     5001341-022  JW2560
5001341-027.........................     5001341-022  JW2589
5001341-028.........................     5001341-022  JW2639
5001341-029.........................     5001341-022  JW2760
5001341-030.........................     5001341-022  JW2792
5001341-031.........................     5001341-022  MO579
5001341-032.........................     5001341-022  MG2825
5001341-033.........................     5001341-022  MG5477
5001341-034.........................     5001341-022  ND5917
------------------------------------------------------------------------

    The added part SNs are as follows:

------------------------------------------------------------------------
                 PNs                     Added  SNs
-----------------------------------------------------
5001341-022..........................          JW4713
5001341-022..........................          MG6743
5001341-022..........................          ND6924
831021-003...........................          ND9177
831021-003...........................          ND9496
831021-003...........................          NS7894
831021-003...........................          NS8559
831021-003...........................          NS9072
804121...............................          PX3805
804121...............................          PX4266
------------------------------------------------------------------------

Conclusion

    We have carefully reviewed the available data, including the 
comments received, and determined that air safety and the public 
interest require proposing this AD with the changes described 
previously. We have determined that these changes will neither increase 
the economic burden on any operator nor increase the scope of the 
proposed AD.

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 products 
of this same type design. For that reason, we are proposing this AD, 
which would require:
     Checking the 1st stage fan blade for a circled, letter I, 
on the approved marking area of the outboard side of the blade 
platform. If the blade has this marking, no further action is required.
     Removing 1st stage fan blades without a circled, letter I, 
on the approved marking area of the outboard side of the blade platform 
if installed; and
     Inspecting the 1st stage fan blade root thickness; and
     Returning to service 1st stage fan blades that pass the 
inspection, after properly marking the blade.

Costs of Compliance

    We estimate that this proposed AD would affect 531 1st stage fan 
blades installed on JT9D-7R4 turbofan engines installed on airplanes of 
U.S. registry. We also estimate that it would take about 0.5 work-hour 
per 1st stage fan blade to perform the proposed actions, and that the 
average labor rate is $80 per work-hour. Based on these figures, we 
estimate the total cost of the proposed AD to U.S. operators to be 
$21,240.

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.

[[Page 9278]]

    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 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. Would 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

    Under the authority delegated to me by the Administrator, the 
Federal Aviation Administration 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 removing Amendment 39-14430 (70 FR 
76381, December 27, 2005), and by adding a new airworthiness directive 
to read as follows:

Pratt & Whitney: Docket No. FAA-2005-23072; Directorate Identifier 
2005-NE-38-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this airworthiness directive (AD) action by April 30, 
2007.

Affected ADs

    (b) This AD supersedes AD 2005-26-09.

Applicability

    (c) This AD applies to Pratt & Whitney (PW) JT9D-7R4 turbofan 
engines. These engines are installed on, but not limited to, Airbus 
A300 and A310, and Boeing 747 and 767 airplanes.

Unsafe Condition

    (d) This AD results from the discovery of inaccurate part 
quantity, part numbers, and serial numbers used in AD 2005-26-09. We 
are issuing this AD to prevent 1st stage fan blade fracture and 
uncontained engine failure, resulting in possible damage to the 
airplane.

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.
    (f) For 1st stage fan blades that are listed by part number (P/
N) and serial number (SN) in Table 1 of this AD, do the following:

                 Table 1.--Affected 1st Stage Fan Blades
------------------------------------------------------------------------
                    P/Ns                                  SNs
------------------------------------------------------------------------
5001341-022.................................  JW2804
5001341-022.................................  JW0354
5001341-022.................................  ND5746
5001341-022.................................  ND5770
5001341-022.................................  JW3992
5001341-022.................................  ND8615
5001341-022.................................  JW0442
5001341-022.................................  JW2317
5001341-022.................................  ND8631
5001341-022.................................  ND8635
5001341-022.................................  JW4624
5001341-022.................................  NE0394
5001341-022.................................  NE0153
5001341-022.................................  NN8054
5001341-022.................................  JW4693
5001341-022.................................  ND7304
5001341-022.................................  MG6108
5001341-022.................................  MG5862
5001341-022.................................  MG5619
5001341-022.................................  NE0308
5001341-022.................................  NE0200
5001341-022.................................  MG6797
5001341-022.................................  JW0230
5001341-022.................................  ND5652
5001341-022.................................  ND5775
5001341-022.................................  JW0251
5001341-022.................................  ND5719
5001341-022.................................  JW0248
5001341-022.................................  ND5785
5001341-022.................................  ND5676
5001341-022.................................  ND5661
5001341-022.................................  JW0265
5001341-022.................................  ND5699
5001341-022.................................  ND5767
5001341-022.................................  JW0259
5001341-022.................................  ND5680
5001341-022.................................  ND5749
5001341-022.................................  JW0235
5001341-022.................................  ND5776
5001341-022.................................  ND8580
5001341-022.................................  MG6039
5001341-022.................................  ND9127
5001341-022.................................  JW4287
5001341-022.................................  JW0262
5001341-022.................................  JW0445
5001341-022.................................  JW4665
5001341-022.................................  MG5901
5001341-022.................................  NE0303
5001341-022.................................  ND8703
5001341-022.................................  JW4574
5001341-022.................................  JW4286
5001341-022.................................  JW4491
5001341-022.................................  JW4630
5001341-022.................................  JW4391
5001341-022.................................  MG6550
5001341-022.................................  MG6776
5001341-022.................................  JW4586
5001341-022.................................  JW0352
5001341-022.................................  JW4261
5001341-022.................................  MG6135
5001341-022.................................  JW4685
5001341-022.................................  MG6772
5001341-022.................................  MG6793
5001341-022.................................  MG7111
5001341-022.................................  ND8618
5001341-022.................................  JW0644
5001341-022.................................  JW4631
5001341-022.................................  JW4651
5001341-022.................................  JW0234
5001341-022.................................  JW4646
804121......................................  NN9016
804121......................................  VJ3393
804121......................................  PX3694
804121......................................  RK9168
804121......................................  PX5023
804121......................................  VJ3324
804121......................................  VJ3504
804121......................................  NN9115
804121......................................  NN8936
804121......................................  PX3816
804121......................................  VJ3412
804121......................................  RK9163
804121......................................  VJ3447
804121......................................  RK9230
804121......................................  RK9109
804121......................................  PX4627
804121......................................  RK8990
804121......................................  SP9459
804121......................................  RK8656
804121......................................  NN8933
804121......................................  VJ3444
804121......................................  ND5864
804121......................................  NN9020
804121......................................  RK8905
804121......................................  SR1733
804121......................................  NN9047
804121......................................  PX3692
804121......................................  PX3786
804121......................................  NN9025
804121......................................  NN9007
804121......................................  RK9100
804121......................................  VJ3399
804121......................................  PX4970
804121......................................  PX5013

[[Page 9279]]

 
804121......................................  RK8904
804121......................................  NN8986
804121......................................  NN8829
804121......................................  VJ3459
804121......................................  RK9143
804121......................................  VJ3414
804121......................................  NN9028
804121......................................  SP1557
804121......................................  PX5003
804121......................................  PX5042
804121......................................  VJ3475
804121......................................  ND7330
804121......................................  PX3714
831021-003..................................  NS8913
831021-003..................................  ND6512
831021-003..................................  ND6941
831021-003..................................  ND9576
831021-003..................................  NS7555
831021-003..................................  NS8286
831021-003..................................  NS7447
831021-003..................................  ND6488
831021-003..................................  ND8296
831021-003..................................  ND6956
831021-003..................................  ND7879
831021-003..................................  ND6509
831021-003..................................  ND9814
831021-003..................................  NN7331
831021-003..................................  ND6991
831021-003..................................  ND6894
831021-003..................................  NS6413
831021-003..................................  ND7344
831021-003..................................  ND6947
831021-003..................................  NN8732
831021-003..................................  ND8536
831021-003..................................  ND6946
831021-003..................................  ND6723
831021-003..................................  ND9294
831021-003..................................  ND9290
831021-003..................................  ND6013
831021-003..................................  ND8937
831021-003..................................  NS7160
831021-003..................................  NS6435
831021-003..................................  NS6591
831021-003..................................  ND9558
831021-003..................................  NS8479
831021-003..................................  NS9382
831021-003..................................  ND8965
831021-003..................................  ND9837
831021-003..................................  ND5959
831021-003..................................  NS6491
831021-003..................................  NS9072
831021-003..................................  ND9625
831021-003..................................  ND6714
831021-003..................................  ND6820
831021-003..................................  ND8972
831021-003..................................  NE0286
831021-003..................................  NE0347
831021-003..................................  ND8010
831021-003..................................  ND8956
831021-003..................................  ND9535
831021-003..................................  ND9831
831021-003..................................  NE0227
831021-003..................................  ND8283
831021-003..................................  ND9730
831021-003..................................  NN7656
831021-003..................................  NS7775
831021-003..................................  ND9815
831021-003..................................  ND6135
831021-003..................................  NS8491
831021-003..................................  NS6395
831021-003..................................  NS8584
831021-003..................................  NN7272
831021-003..................................  MG7159
831021-003..................................  NS6592
831021-003..................................  ND7862
831021-003..................................  ND6684
831021-003..................................  NN7744
831021-003..................................  ND7480
831021-003..................................  ND7873
831021-003..................................  ND6827
831021-003..................................  ND6576
831021-003..................................  ND9261
831021-003..................................  NS8686
831021-003..................................  ND9052
831021-003..................................  ND6897
831021-003..................................  ND6565
831021-003..................................  NN8966
831021-003..................................  PX3707
831021-003..................................  NS7031
831021-003..................................  ND6584
831021-003..................................  ND9883
831021-003..................................  NS6535
831021-003..................................  ND7852
831021-003..................................  ND9662
831021-003..................................  ND7871
831021-003..................................  JW0106
831021-003..................................  ND8305
831021-003..................................  NS6409
831021-003..................................  NE0442
831021-003..................................  ND9095
831021-003..................................  ND9302
831021-003..................................  ND9023
831021-003..................................  ND8009
831021-003..................................  ND8477
831021-003..................................  ND7492
831021-003..................................  ND8776
831021-003..................................  ND6524
831021-003..................................  ND6704
831021-003..................................  ND8911
831021-003..................................  ND8789
831021-003..................................  ND8798
831021-003..................................  ND6407
831021-003..................................  ND7668
831021-003..................................  ND9179
831021-003..................................  NE0421
831021-003..................................  ND6513
831021-003..................................  ND6744
831021-003..................................  ND7654
831021-003..................................  ND7870
831021-003..................................  ND9759
831021-003..................................  ND6561
831021-003..................................  ND5826
831021-003..................................  ND6031
831021-003..................................  ND8714
831021-003..................................  ND8872
831021-003..................................  ND6678
831021-003..................................  ND6629
831021-003..................................  ND8995
831021-003..................................  NE0302
831021-003..................................  ND6405
831021-003..................................  NS8300
831021-003..................................  NS8769
831021-003..................................  NS7147
831021-003..................................  ND6649
831021-003..................................  ND7766
831021-003..................................  NS7864
831021-003..................................  NS8734
831021-003..................................  ND6677
831021-003..................................  NS7911
831021-003..................................  ND8205
831021-003..................................  ND8804
831021-003..................................  ND6639
831021-003..................................  ND8994
831021-003..................................  ND7275
831021-003..................................  ND9195
831021-003..................................  ND6178
831021-003..................................  ND8639
831021-003..................................  ND9760
831021-003..................................  ND9108X
831021-003..................................  ND6427
831021-003..................................  ND6590
831021-003..................................  NS6551
831021-003..................................  JW1158
831021-003..................................  ND6412
831021-003..................................  ND7922
831021-003..................................  NS8678
831021-003..................................  ND8930
831021-003..................................  ND6596
831021-003..................................  ND9570
831021-003..................................  NN9027
831021-003..................................  ND6446
831021-003..................................  NE0275
831021-003..................................  ND9917
831021-003..................................  NS7919
831021-003..................................  NS7907
831021-003..................................  ND6583
831021-003..................................  NN7420
831021-003..................................  ND7746
831021-003..................................  ND8187
831021-003..................................  NN8999
831021-003..................................  ND6043
831021-003..................................  ND7880
831021-003..................................  NN7175
831021-003..................................  ND9816
831021-003..................................  ND8174
831021-003..................................  ND6045
831021-003..................................  NS7562
831021-003..................................  JW0075
831021-003..................................  ND6848
831021-003..................................  ND8531
831021-003..................................  ND6311
831021-003..................................  ND8144
831021-003..................................  ND5798
831021-003..................................  ND8113
831021-003..................................  ND9642
831021-003..................................  ND7436
831021-003..................................  ND9054
831021-003..................................  ND9683
831021-003..................................  ND5991
831021-003..................................  ND6026
831021-003..................................  ND6616
831021-003..................................  ND6530
831021-003..................................  NE0374
831021-003..................................  ND6364
831021-003..................................  ND7718
831021-003..................................  ND6473
831021-003..................................  ND6436
831021-003..................................  ND6887
831021-003..................................  ND6518
831021-003..................................  ND6479
831021-003..................................  NS6330
831021-003..................................  ND7264
831021-003..................................  ND8151
831021-003..................................  ND6562
831021-003..................................  NS8776
831021-003..................................  ND6519
831021-003..................................  ND7659
831021-003..................................  NS9049
831021-003..................................  NS6861
831021-003..................................  ND9571
831021-003..................................  ND9346
831021-003..................................  ND6501
831021-003..................................  NS8505

[[Page 9280]]

 
831021-003..................................  ND9338
831021-003..................................  ND9775
831021-003..................................  ND6485
831021-003..................................  ND7165
831021-003..................................  ND9371
831021-003..................................  ND9537
831021-003..................................  NS7889
831021-003..................................  ND7877
831021-003..................................  ND8670
831021-003..................................  ND9032
831021-003..................................  ND8781
831021-003..................................  ND8604
831021-003..................................  ND9329
831021-003..................................  ND9110
831021-003..................................  ND5997
831021-003..................................  ND6027
831021-003..................................  ND9589
831021-003..................................  ND6575
831021-003..................................  ND6592
831021-003..................................  ND6463
831021-003..................................  NS8583
831021-003..................................  NS8590
831021-003..................................  NS8567
831021-003..................................  NS6795
831021-003..................................  NS7110
831021-003..................................  NS6587
831021-003..................................  NS6404
831021-003..................................  ND6486
5001341-022.................................  JW0942
5001341-022.................................  ND9231
5001341-022.................................  JW4812
5001341-022.................................  ND6555
5001341-022.................................  M1375
5001341-022.................................  MG6627
5001341-022.................................  MG6794
5001341-022.................................  ND9399
5001341-022.................................  NE0084
5001341-022.................................  MG6252
5001341-022.................................  ND7422
5001341-022.................................  ND7043
5001341-022.................................  MG5722
5001341-022.................................  MG5918
5001341-022.................................  ND6984
5001341-022.................................  M0839
5001341-022.................................  M0922
5001341-022.................................  M0938
5001341-022.................................  M1117
5001341-022.................................  M0307
5001341-022.................................  JW3871
5001341-022.................................  M1125
5001341-022.................................  M1149
5001341-022.................................  JW2681
5001341-022.................................  M0270
5001341-022.................................  M1120
5001341-022.................................  M0205
5001341-022.................................  AE9352
5001341-022.................................  JW3492
5001341-022.................................  ND6148
5001341-022.................................  ND8907
5001341-022.................................  M1235
5001341-022.................................  MG5585
5001341-022.................................  ND8436
5001341-022.................................  MG5696
5001341-022.................................  ND8704
5001341-022.................................  JW2284
5001341-022.................................  JW2313
5001341-022.................................  JW2498
5001341-022.................................  JW2541
5001341-022.................................  JW2560
5001341-022.................................  JW2589
5001341-022.................................  JW2639
5001341-022.................................  JW2760
5001341-022.................................  JW2792
5001341-022.................................  M0579
5001341-022.................................  MG2825
5001341-022.................................  MG5477
5001341-022.................................  ND5917
5001341-022.................................  JW1976
5001341-022.................................  JW2653
5001341-022.................................  JW2608
5001341-022.................................  JW2727
5001341-022.................................  JW2764
5001341-022.................................  JW2265
5001341-022.................................  JW2474
5001341-022.................................  JW2396
5001341-022.................................  JW3554
5001341-022.................................  JW2667
5001341-022.................................  MG2302
5001341-022.................................  MG3972
5001341-022.................................  JW3930
5001341-022.................................  ND6749
5001341-022.................................  M1172
5001341-022.................................  JW2104
5001341-022.................................  JW2519
5001341-022.................................  JW2640
5001341-022.................................  JW2517
5001341-022.................................  JW2663
5001341-022.................................  JW2823
5001341-022.................................  M0536
5001341-022.................................  JW2725
5001341-022.................................  MG5917
5001341-022.................................  JW0681
5001341-022.................................  JW0711
5001341-022.................................  JW0740
5001341-022.................................  JW0807
5001341-022.................................  JW1089
5001341-022.................................  JW1362
5001341-022.................................  JW2065
5001341-022.................................  MG2434
5001341-022.................................  MG2846
5001341-022.................................  JW0806
804121......................................  NN9854
804121......................................  NN9024
804121......................................  NN9032
804121......................................  PX5029
804121......................................  NN9050
804121......................................  NS8242
804121......................................  NS8260
804121......................................  PX4273
804121......................................  PX4378
804121......................................  RL0857
804121......................................  RX8763
804121......................................  NS8331
804121......................................  NN9824
804121......................................  MG6979
804121......................................  MG7023
804121......................................  MG7055
804121......................................  RK8914
804121......................................  RL0023
804121......................................  PX4328
804121......................................  RK9008
804121......................................  TG1506
804121......................................  KK8226
804121......................................  MG2604
804121......................................  NS6691
804121......................................  RK8968
804121......................................  NN9917
804121......................................  RK7824
804121......................................  M1343
804121......................................  NS6559
804121......................................  NS7767
804121......................................  NE0363
804121......................................  PX3771
804121......................................  NN9972
804121......................................  RL0460
804121......................................  RK8310
804121......................................  SR2115
804121......................................  TG2826
804121......................................  PX5018
804121......................................  PX5002
831021-003..................................  ND7627
831021-003..................................  ND6890
831021-003..................................  ND7461
831021-003..................................  ND9616
831021-003..................................  NE0413
831021-003..................................  NS8825
831021-003..................................  NS6350
831021-003..................................  NS7168
831021-003..................................  NS7705
831021-003..................................  NS7848
831021-003..................................  ND9128
831021-003..................................  ND9541
831021-003..................................  ND9671
831021-003..................................  ND9684
831021-003..................................  NE0277
831021-003..................................  NE0384
831021-003..................................  NE0396
831021-003..................................  ND6421
831021-003..................................  ND6599
831021-003..................................  ND6614
831021-003..................................  ND7847
831021-003..................................  ND8346
831021-003..................................  ND8853
831021-003..................................  ND8915
831021-003..................................  NS8719
831021-003..................................  NS8838
831021-003..................................  NT0169
831021-003..................................  NS9584
831021-003..................................  ND6445
831021-003..................................  ND6834
831021-003..................................  ND7467
831021-003..................................  ND8887
831021-003..................................  ND6520
831021-003..................................  NS8611
831021-003..................................  NS7640
831021-003..................................  NN7037
831021-003..................................  NN7590
831021-003..................................  NN8120
831021-003..................................  NN8573
831021-003..................................  NN9719
831021-003..................................  NS8784
831021-003..................................  TB6B367
831021-003..................................  NN9557
831021-003..................................  NN9710
831021-003..................................  NS8374
831021-003..................................  NS8770
831021-003..................................  NS9022
831021-003..................................  NS8416
831021-003..................................  NS6474
831021-003..................................  ND8912
831021-003..................................  NT0108
831021-003..................................  NS8836
831021-003..................................  NN8310
831021-003..................................  NS8559
5001341-022.................................  JW4713
5001341-022.................................  MG6743
5001341-022.................................  ND6924
831021-003..................................  ND9177
831021-003..................................  ND9496
831021-003..................................  NS7894
831021-003..................................  NS8559
831021-003..................................  NS9072
804121......................................  PX3805

[[Page 9281]]

 
804121......................................  PX4266
------------------------------------------------------------------------

For Engines Installed on an Airplane

    (1) For engines installed on an airplane with affected 1st stage 
fan blades installed, perform the actions in paragraphs (f)(3) 
through (f)(6)(ii) of this AD at the next 1st stage fan blade 
exposure.

For Engines Not Installed on an Airplane, or, for Affected 1st Stage 
Fan Blades Not Installed in an Engine

    (2) For engines not installed on an airplane with affected 1st 
stage fan blades installed, or, for affected 1st stage fan blades 
not installed in an engine, paragraph (h) of this AD applies.

1st Stage Fan Blade Check

    (3) Check the 1st stage fan blade for a circled, letter I, on 
the approved marking area of the outboard side of the blade 
platform. If the blade has this marking, no further action is 
required.
    (4) Remove 1st stage fan blades without a circled, letter I, on 
the approved marking area of the outboard side of the blade 
platform, if installed.
    (5) Inspect the 1st stage fan blade root thickness. You can find 
information on inspecting the blade root thickness in PW Engine 
Manual Section 72-31-02, Inspect-01, and Repair-23.
    (6) For 1st stage fan blades that pass the inspection referenced 
in paragraph (f)(5) of this AD:
    (i) Vibropeen the letter I and a circle around that letter, on 
the approved marking area of the outboard side of the blade 
platform. You can find information on approved blade marking in the 
JT9D-7R4 Engine Manual, Section 72-31-02, Typical Repair-13, Mark 
Repair Codes.
    (ii) Return the 1st stage fan blades to service.

Definition

    (g) For the purposes of paragraph (f)(1) of this AD, next 1st 
stage fan blade exposure is:
    (1) When any 1st stage fan blade is removed from the engine; or
    (2) When the 1st stage fan hub is removed from the engine.

Prohibited Installation

    (h) After the effective date of this AD, do not install any 1st 
stage fan blades listed in Table 1 of this AD on any airplane, 
unless the actions of this AD have been done to the 1st stage fan 
blades.

Alternative Methods of Compliance

    (i) 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

    (j) None.

    Issued in Burlington, Massachusetts, on February 23, 2007.
Peter A. White,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
 [FR Doc. E7-3561 Filed 2-28-07; 8:45 am]
BILLING CODE 4910-13-P

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