AD 99-25933

[Federal Register Volume 64, Number 193 (Wednesday, October 6, 1999)] [Proposed Rules] [Pages 54232-54234] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 99-25933]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-221-AD] RIN 2120-AA64

Airworthiness Directives; Lockheed Model L-1011-385 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Lockheed Model L-1011-385 series airplanes. This proposal would require modification of the high pressure bleed valve controller of each engine. This proposal is prompted by reports of failure of the bleed air system components such as the thermal compensators and bleed air ducts. The actions specified by the proposed AD are intended to prevent such failures of the bleed air system components, which could result in high temperature air leaking into the cabin and/or cargo areas and could possibly require an emergency landing and evacuation.

DATES: Comments must be received by November 22, 1999.

ADDRESSES: Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 99-NM-221-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except Federal holidays. The service information referenced in the proposed rule may be obtained from Lockheed Martin Aircraft & Logistics Center, 120 Orion Street, Greenville, South Carolina 29605. This information

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may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Small Airplane Directorate, Atlanta Aircraft Certification Office, One Crown Center, 1895 Phoenix Boulevard, suite 450, Atlanta, Georgia.

FOR FURTHER INFORMATION CONTACT: Thomas Peters, Aerospace Engineer, Systems and Flight Test Branch, ACE-116A, FAA, Small Airplane Directorate, Atlanta Aircraft Certification Office, One Crown Center, 1895 Phoenix Boulevard, suite 450, Atlanta, Georgia 30349; telephone (770) 703-6063; fax (770) 703-6097.

SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to participate in the making of the proposed rule by submitting such written data, views, or arguments as they may desire. Communications shall identify the Rules Docket number and be submitted in triplicate to the address specified above. All communications received on or before the closing date for comments, specified above, will be considered before taking action on the proposed rule. The proposals contained in this notice may be changed in light of the comments received. Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the proposed rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report summarizing each FAA-public contact concerned with the substance of this proposal will be filed in the Rules Docket. Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this notice must submit a self-addressed, stamped postcard on which the following statement is made: ``Comments to Docket Number 99-NM-221-AD.'' The postcard will be date stamped and returned to the commenter.

Availability of NPRMs

Any person may obtain a copy of this NPRM by submitting a request to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 99-NM-221-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

The FAA has received reports of failures of the bleed air system components, such as the thermal compensators and bleed air ducts, on certain Lockheed Model L-1011-385 series airplanes. Investigation revealed that during a selection of the anti-ice mode, a sudden overpressure spike condition of the bleed air system can occur. This overpressure spike condition is caused when the engine high pressure bleed valve is opened rapidly by its controller. This overpressure has contributed to failures of the bleed air system components. Such failures of the bleed air system components, if not corrected, could result in high temperature air leaking into the cabin and/or cargo areas and could possibly require an emergency landing and evacuation.

Explanation of Relevant Service Information

The FAA has reviewed and approved Lockheed Service Bulletin 093-36- 065, dated February 9, 1999, which describes procedures for modification of the high pressure bleed valve controller of each engine. The modification involves the installation of a specific restrictor check valve into the high pressure bleed valve controller of each engine. Accomplishment of the action specified in the service bulletin is intended to adequately address the identified unsafe condition. The Lockheed service bulletin references Hamilton Standard Service Bulletin 36-1060, Revision 1, dated March 1, 1977, as an additional source of service information for accomplishing the modification.

Explanation of Requirements of Proposed Rule

Since an unsafe condition has been identified that is likely to exist or develop on other products of this same type design, the proposed AD would require accomplishment of the actions specified in the service bulletin described previously, except as discussed below.

Differences Between Proposed Rule and Service Information

Operators should note that the Lockheed service bulletin (described previously) provides service information for accomplishing the modification of the high pressure bleed valve controller with the installation of Hamilton Standard restrictor check valve part number (P/N) 764898-2 in the high pressure bleed valve controller P/N 739084- 3. However, this proposed AD would be applicable to those airplanes that are equipped with high pressure bleed valve controller P/N 739084- 2 or 739084-3. The high pressure bleed valve controller P/N 739084-2 has no restrictor check valve installed, and the bleed valve controller P/N 739084-3 has a restrictor check valve installed that occasionally causes an inability to supply bleed augmentation. To reduce the probability of either a rupture of the bleed air system or the inability to deliver additional bleed, this proposed AD would require the modification of both high pressure bleed valve controller types to the latest configuration (P/N 739084-4) with the installation of the restrictor check valve P/N 764898-2.

Cost Impact

There are approximately 235 airplanes of the affected design in the worldwide fleet. The FAA estimates that 116 airplanes of U.S. registry would be affected by this proposed AD, that it would take approximately 2 work hours per airplane to accomplish the proposed replacement, and that the average labor rate is $60 per work hour. Required parts would cost approximately $650 per airplane. Based on these figures, the cost impact of the proposed AD on U.S. operators is estimated to be $89,320, or $770 per airplane. The cost impact figure discussed above is based on assumptions that no operator has yet accomplished any of the proposed requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted.

Regulatory Impact

The regulations proposed herein would not have substantial direct effects on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government. Therefore, in accordance with Executive Order 12612, it is determined that this proposal would not have sufficient federalism implications to warrant the preparation of a Federalism Assessment. For the reasons discussed above, I certify that this proposed regulation (1) is not a ``significant regulatory action'' under Executive Order 12866; (2) is not a ``significant rule'' under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) if promulgated, will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. A copy of the draft regulatory evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting the Rules Docket at the location provided under the caption ADDRESSES.

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List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend part 39 of the Federal Aviation Regulations (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. Section 39.13 is amended by adding the following new airworthiness directive:

Lockheed: Docket 99-NM-221-AD.

Applicability: Model L-1011-385-1, -1-14, -1-15, and -3 series airplanes equipped with high pressure bleed valve controller Hamilton Standard part number (P/N) 739084-2 or 739084-3 (Lockheed P/N 672286-103 or 672286-105); certificated in any category.

Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (c) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Compliance: Required as indicated, unless accomplished previously. To prevent failures of the bleed air system components, which could result in high temperature air leaking into the cabin and/or cargo areas and could possibly require an emergency landing and evacuation, accomplish the following: (a) Within 14 months after the effective date of this AD, modify the high pressure bleed valve controller of each engine in accordance with Lockheed Service Bulletin 093-36-065, dated February 9, 1999.

Note 2: Hamilton Standard has issued Service Bulletin 36-1060, Revision 1, dated March 1, 1977, as an additional source of service information for the modification of the high pressure bleed valve controller of each engine.

(b) As of the effective date of this AD, no person shall install on any airplane a high pressure bleed valve controller, unless it has been modified in accordance with this AD.

Alternative Methods of Compliance

(c) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Atlanta Aircraft Certification Office (ACO), FAA, Small Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Atlanta ACO.

Note 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Atlanta ACO.

Special Flight Permits

(d) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished. Issued in Renton, Washington, on September 29, 1999. D.L. Riggin, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 99-25933 Filed 10-5-99; 8:45 am] BILLING CODE 4910-13-U