Federal Aviation Administration, DOT.
Notice of proposed rulemaking (NPRM).
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Boeing Model 737-300, -400, and -500 series airplanes. This proposal would require replacement of the hinge assemblies on certain escape slide compartments of the forward doors with new, stronger hinge assemblies. This action is necessary to prevent forward door escape slides from falling out of their compartments into the airplane interior and inflating, which could impede an evacuation in the event of emergency. This action is intended to address the identified unsafe condition.
Comments must be received by August 23, 2002.
Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2001-NM-88-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: firstname.lastname@example.org. Comments sent via fax or the Internet must contain “Docket No. 2001-NM-88-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 for Windows 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.Start Further Info
FOR FURTHER INFORMATION CONTACT:
Technical Information: Keith Ladderud, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 227-2780; fax (425) 227-1181.
Other Information: Sandi Carli, Airworthiness Directive Technical Editor/Writer; telephone (425) 687-4243, fax (425) 227-1232. Questions or comments may also be sent via the Internet using the following address: email@example.com. Questions or comments sent via the Internet as attached electronic files must be formatted in Microsoft Word 97 for Windows or ASCII text.End Further Info End Preamble Start Supplemental Information
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. Start Printed Page 45413
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 2001-NM-88-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. 2001-NM-88-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.
The FAA has received a report of an incident on a Boeing Model 737-300 series airplane in which a forward door escape slide fell out of its compartment and inflated inside the passenger compartment of the airplane. Other operators have reported incidents in which the forward door escape slides dropped out of their ostensibly secured compartments. Investigation has revealed that the soft aluminum hinge assemblies on Model 737-300, -400, and -500 series airplanes are susceptible to deformation. A deformed hinge assembly could allow the escape slide to fall out of its compartment into the interior of the airplane. The released slide, which would automatically inflate, could impede an evacuation in the event of an emergency.
Airplanes Similar to Model 737-300 Series Airplanes
The hinge assemblies on certain escape slide compartments of the forward doors on certain Model 737-400 and 737-500 series airplanes are identical to those installed on certain Model 737-300 series airplanes. Therefore, all of these models may be subject to the same unsafe condition.
Explanation of Relevant Service Information
The FAA has reviewed and approved Boeing Service Bulletin 737-25-1430, dated February 22, 2001, which describes procedures for replacing the hinge assemblies on the stowage compartments for the forward door escape slides with new, stronger hinge assemblies. Accomplishment of the actions specified in the service bulletin is intended to adequately address the identified unsafe condition.
AD 96-18-04, amendment 39-9728 (61 FR 45878, August 30, 1996), requires accomplishment of the actions specified in Boeing Service Bulletin 737-25A1221 and Air Cruisers Service Bulletin 103-25-19. Those service bulletins are also cited in Boeing Service Bulletin 737-25-1430 as “concurrent requirements.” Because those “concurrent” actions are required by AD 96-18-04, they are not included in this proposed AD.
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 Boeing Service Bulletin 737-25-1430, described previously.
There are approximately 1,974 airplanes of the affected design in the worldwide fleet. The FAA estimates that 793 airplanes of U.S. registry would be affected by this proposed AD, that it would take approximately 5 work hours per airplane to accomplish the proposed actions, and that the average labor rate is $60 per work hour. Required parts would cost approximately $671 per airplane. Based on these figures, the cost impact of the proposed AD on U.S. operators is estimated to be $770,003, or $971 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.
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.Start List of Subjects
List of Subjects in 14 CFR Part 39
- Air transportation
- Aviation 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:Start Part
PART 39—AIRWORTHINESS DIRECTIVES
1. The authority citation for part 39 continues to read as follows:
2. Section 39.13 is amended by adding the following new airworthiness directive:
Boeing: Docket 2001-NM-88-AD.
Applicability: Model 737-300, -400, and -500 series airplanes; certificated in any category; as listed in Boeing Service Bulletin 737-25-1430, dated February 22, 2001.
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 Start Printed Page 45414airplanes 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 forward door escape slides from falling out of their compartments into the airplane interior and inflating, which could impede an evacuation in the event of emergency, accomplish the following:
Hinge Assembly Replacement
(a) Within 24 months after the effective date of this AD, replace the hinge assemblies on the escape slide stowage compartments of the forward doors with new, stronger hinge assemblies, in accordance with Boeing Service Bulletin 737-25-1430, dated February 22, 2001.
(b) As of the effective date of this AD, no person may install a hinge assembly, part number 65C30431-6 or 65C30431-7, on any airplane.
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, Seattle Aircraft Certification Office (ACO), FAA. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Seattle ACO.
Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO.
Special Flight Permits
(d) Special flight permits may be issued in accordance with §§ 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 June 28, 2002.
Jeffrey E. Duven,
Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.
[FR Doc. 02-17081 Filed 7-8-02; 8:45 am]
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