03-30336. Airworthiness Directives; Boeing Model 747-100, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F, and 747 SR Series Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Boeing Model 747-100, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F, and 747 SR series airplanes. This proposal would require inspection of fire extinguisher bottles in the engine and the auxiliary power unit (APU) to determine the part number; and replacement of the fire extinguisher bottles with new fire extinguisher bottles, if necessary. This action is necessary to prevent fractured discharge heads, which could cause the fire extinguishing agent to leak, which could result in an uncontrolled engine fire that could spread to the strut and wing, or an uncontrolled APU fire that could spread to the airplane structure. This action is intended to address the identified unsafe condition.

DATES:

Comments must be received by January 22, 2004.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2003-NM-82-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9 a.m. and 3 p.m., Monday through Friday, except Federal holidays. Comments may be submitted via fax to [phone]. Comments may also be sent via the Internet using the following address: [e-mail]. Comments sent via fax or the Internet must contain “Docket No. 2003-NM-82-AD” in the subject line and need not be submitted in triplicate. Comments sent via the Internet as attached electronic files must be formatted in Microsoft Word 97 or 2000 or ASCII text.

The service information referenced in the proposed rule may be obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124-2207. This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington.

FOR FURTHER INFORMATION CONTACT:

Sulmo Mariano, Aerospace Engineer, Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4086; telephone [phone]; fax [phone].

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 action may be changed in light of the comments received.

Submit comments using the following format:

• Organize comments issue-by-issue. For example, discuss a request to change the compliance time and a request to change the service bulletin reference as two separate issues.
• For each issue, state what specific change to the proposed AD is being requested.
• Include justification (e.g., reasons or data) for each request.

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 action must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket Number 2003-NM-82-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. 2003-NM-82-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

The FAA has received reports of fractures of the discharge heads on certain fire extinguisher bottles in the engine and auxiliary power unit (APU) of Model 747-400 series airplanes. In one case, the discharge head fractured during installation of the fire extinguisher. In another case, two fire extinguisher bottles discharged during a tailpipe fire were found to have fractured discharge heads. Four other discharge heads were removed from service after an operator performed an x-ray inspection and found hairline cracks. The cause of the cracking and fractures was traced to discharge heads that were manufactured from a cast material, which had sharp edges or burrs on the retaining rings. These sharp edges or burrs caused the discharge head to seat incorrectly. When the discharge head nuts were tightened, the discharge heads fractured at the retaining ring groove. Fractured discharge heads could cause the fire extinguishing agent to leak from the discharge head. As a consequence, there would not be enough fire extinguishing agent to extinguish a fire in the engine or APU fire zone. This condition, if not corrected, could result in fractured heads which could cause the fire extinguishing agent to leak, which could result in an uncontrolled engine fire that could spread to the strut and wing, or an uncontrolled APU fire that could spread to the airplane structure.

The subject area on certain Model 747-100, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F, and 747 SR series airplanes is almost identical to that on the affected Model 747-400 series airplanes. Therefore, those Model 747-400 series airplanes may be subject to the same unsafe condition revealed on the Model 747-100, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F, and 747 SR series airplanes.

Explanation of Relevant Service Information

The FAA has reviewed and approved Boeing Alert Service Bulletin 747-26A2272, dated January 16, 2003, which describes procedures for inspecting the fire extinguisher bottles in the engine and APU to determine the part number; and, if necessary, replacement of the fire extinguisher bottles with new fire extinguisher bottles that have discharge heads machined from forged rather than cast material. Accomplishment of the actions specified in the service bulletin is intended to adequately address the identified unsafe condition.

Boeing Alert Service Bulletin 747-26A2272 refers to Kidde Aerospace Service Bulletin A820400-26-432, dated October 19, 2002; and Kidde Aerospace Service Bulletin A830800-26-433, dated October 19, 2002; as additional sources of service information for accomplishment of the inspection and replacement, if necessary, for Model 747-100, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F, and 747 SR series airplanes.

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 Boeing service bulletin described previously.

Cost Impact

There are approximately 346 airplanes of the affected design in the worldwide fleet. The FAA estimates that 47 airplanes of U.S. registry would be affected by this proposed AD, that it would take approximately 1 work hour per airplane to accomplish the proposed inspection, and that the average labor rate is $65 per work hour. Based on these figures, the cost impact of the proposed AD on U.S. operators is estimated to be $3,055, or $65 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 proposed AD were not adopted. The cost impact figures discussed in AD rulemaking actions represent only the time necessary to perform the specific actions actually required by the AD. These figures typically do not include incidental costs, such as the time required to gain access and close up, planning time, or time necessitated by other administrative actions.

Regulatory Impact

The regulations proposed herein 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. Therefore, it is determined that this proposal would not have federalism implications under Executive Order 13132.

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.

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.

§ 39.13

[Amended]

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

Boeing: Docket 2003-NM-82-AD.

Applicability: Boeing Model 747-100, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F, and 747 SR series airplanes, as listed in Boeing Alert Service Bulletin 747-26A2272, dated January 16, 2003; certificated in any category.

Compliance: Required as indicated, unless accomplished previously.

To prevent fractured discharge heads, which could cause the fire extinguishing agent to leak, which could result in an uncontrolled engine fire that could spread to the strut and wing, or an uncontrolled auxiliary power unit (APU) fire that could spread to the airplane structure, accomplish the following:

Inspection and Replacement

(a) Within two years after the effective date of this AD: Perform an inspection to determine the part number (P/N) of the fire extinguisher bottles in the engine and the APU per the Accomplishment Instructions of Boeing Alert Service Bulletin 747-26A2272, dated January 16, 2003.

Note 1:

Boeing Alert Service Bulletin 747-26A2272 refers to Kidde Aerospace Service Bulletin A820400-26-432, dated October 19, 2002; and Kidde Aerospace Service Bulletin A830800-26-433, dated October 19, 2002; as additional sources of service information for accomplishment of the inspection and replacement, if necessary, for Model 747-100, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F, and 747 SR series airplanes.

(1) If no “Pre SB A820400-26-432” P/N listed in Table 2 of Kidde Aerospace Service Bulletin A820400-26-432, dated October 19, 2002, is found installed; and if no “Pre SB A830800-26-433” P/N listed in Table 2 of Kidde Aerospace Service Bulletin A830800-26-433, dated October 19, 2002 is found installed; no further action is required by this paragraph.

(2) If any “Pre SB A820400-26-432” P/N listed in Table 2 of Kidde Aerospace Service Bulletin A820400-26-432, dated October 19, 2002 is found installed; or if any “Pre SB A830800-26-433” P/N listed in Table 2 of Kidde Aerospace Service Bulletin A830800-26-433, dated October 19, 2002 is found installed, prior to further flight, replace the fire extinguisher bottle with a new fire extinguisher bottle having the “Post SB” P/N listed in Table 2 of the applicable Kidde Aerospace service bulletin. Do the actions per the Accomplishment Instructions of Boeing Alert Service Bulletin 747-26A2272, dated January 16, 2003.

Parts Installation

(b) As of the effective date of this AD, no person may install on any airplane a Kidde Aerospace fire extinguisher bottle with any “Pre SB A820400-26-432” P/N listed in Table 2 of Kidde Aerospace Service Bulletin A820400-26-432, dated October 19, 2002; or any “Pre SB A830800-26-433” P/N listed in Table 2 of Kidde Aerospace Service Bulletin A830800-26-433, dated October 19, 2002.

Alternative Methods of Compliance

(c) In accordance with 14 CFR 39.19, the Manager, Seattle Aircraft Certification Office (ACO), FAA, is authorized to approve alternative methods of compliance (AMOCs) for this AD.

Issued in Renton, Washington, on December 1, 2003.

Ali Bahrami,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.