Airworthiness Directives; Boeing Model 747-100, -100B, -100B SUD, -200B, -200C, -200F, -300, 747SR, and 747SP Series Airplanes Equipped With Pratt & Whitney JT9D-3, -7, -7Q, and -7R4G2 Series Engines

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Supplemental notice of proposed rulemaking; reopening of comment period.

SUMMARY:

This document revises an earlier proposed airworthiness directive (AD), applicable to certain Boeing transport category airplanes listed above, that would have required drilling witness holes through the cowl skin at the cowl latch locations in the left-hand side of the cowl panel assembly of each engine. This new action revises the proposed rule by adding certain airplanes and removing certain JT9D engines from the applicability. The actions specified by this new proposed AD are intended to prevent improper connection of the latch, which could result in separation of a cowl panel from the airplane. Such separation could cause damage to the airplane, consequent rapid depressurization, and hazards to persons or property on the ground. This action is intended to address the identified unsafe condition.

DATES:

Comments must be received by March 2, 2004.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2002-NM-207-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 (425) 227-1232. Comments may also be sent via the Internet using the following address: 9-anm-nprmcomment@faa.gov. Comments sent via fax or the Internet must contain “Docket No. 2002-NM-207-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 Airplanes, 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:

Dan Kinney, Aerospace Engineer, Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 917-6499; fax (425) 917-6590.

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 2002-NM-207-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. 2002-NM-207-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to add an airworthiness directive (AD), applicable to certain Boeing Model 747-100, -100B, -100B SUD, -200B, -200C, -200F, -300, 747SR, and 747SP series airplanes equipped with Pratt & Whitney JT9D series engines, was published as a notice of proposed rulemaking (NPRM) (hereafter referred to as the “original NPRM”) in the Federal Register on July 9, 2003 (68 FR 40827). That original NPRM would have required drilling witness holes through the cowl skin at the cowl latch locations in the left-hand side of the cowl panel assembly of each engine. That original NPRM was prompted by a report of in-flight separation of the cowl panels on the left- and right-hand sides of a Model 747 series airplane. That condition, if not corrected, could result in damage to the airplane, consequent rapid depressurization, and hazards to persons or property on the ground.

Comments

Due consideration has been given to the comment received in response to the original NPRM. That comment, as discussed below, has resulted in changes to the supplemental NPRM.

Request for Change in Applicability

One commenter requests that we remove Pratt & Whitney JT9D-70A engines from the applicability of the original NPRM. The commenter states that the side cowl panels for JT9D-70A engines have a different configuration than the other JT9D series engines.

We agree. Since Pratt & Whitney JT9D-70A engines have a different configuration, the corrective action as specified in paragraph (a) of this supplemental NPRM is not applicable to JT9D-70A engines. We have revised the applicability of this supplemental NPRM to identify only the affected engines.

The commenter also requests that we add Model 747 series airplanes, line numbers 670 to 814 inclusive, to the applicability of the original NPRM. The commenter states that since the side cowls are readily interchangeable among JT9D series engines equipped on Model 747 series airplanes, the applicability should include all delivered Model 747 series airplanes equipped with JT9D-3, -7, -7Q, and -7R4G2 series engines.

We agree. Since issuance of the original NPRM, we have reviewed and approved Revision 1 of Boeing Special Attention Service Bulletin 747-71-2301, dated August 21, 2003, which adds additional airplanes, line numbers 670 through 814 inclusive, to the applicability. We have revised this supplemental NPRM to specify the new applicability and to reference Revision 1 of the service bulletin as the appropriate source of service information for accomplishing the required actions. We have also added paragraph (b) of this supplemental NPRM to give credit for actions accomplished per the original issue of the service bulletin. Furthermore, we have revised the cost impact to include the additional cost of these airplanes to U.S. operators.

Conclusion

Since these changes expand the scope of the originally proposed rule, the FAA has determined that it is necessary to reopen the comment period to provide additional opportunity for public comment.

Cost Impact

There are approximately 481 airplanes of the affected design in the worldwide fleet. The FAA estimates that 114 airplanes of U.S. registry would be affected by this proposed AD, that it would take approximately 8 work hours per airplane (2 work hours per engine) to accomplish the proposed actions, 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 $59,280, or $520 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. 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.