[Federal Register Volume 61, Number 83 (Monday, April 29, 1996)]
[Proposed Rules]
[Pages 18705-18707]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-10506]
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DEPARTMENT OF AGRICULTURE
DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 95-NM-218-AD]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 747-400 Series Airplanes
Equipped With BFGoodrich Evacuation Slide/Rafts
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 Boeing Model 747-400
series airplanes. This proposal would require modification of door 5
evacuation slide/rafts. This proposal is prompted by reports that the
door 5 evacuation slide/raft failed to deploy properly due to adverse
loads caused by the geometry of this evacuation slide/raft. The actions
specified by the proposed AD are
[[Page 18706]]
intended to prevent failure of the door 5 evacuation slide/raft to
deploy properly, which could contribute to injury of passengers on the
slide and could delay or impede the evacuation of passengers during an
emergency.
DATES: Comments must be received by June 10, 1996.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 95-NM-218-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 BFGoodrich Company, Aircraft Evacuation Systems,
Department 7916, Phoenix, Arizona 85040. This information may be
examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue,
SW., Renton, Washington; or at the FAA, Transport Airplane Directorate,
Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard,
Lakewood, California.
FOR FURTHER INFORMATION CONTACT: Andrew Gfrerer, Aerospace Engineer,
Systems and Equipment Branch, ANM-130L, FAA, Los Angeles Aircraft
Certification Office, 3960 Paramount Boulevard, Lakewood, California
90712; telephone (310) 627-5338; fax (310) 627-5210.
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 95-NM-218-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-103, Attention: Rules
Docket No. 95-NM-218-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
Discussion
The FAA has received reports indicating that the door 5 evacuation
slide/raft installed on Boeing Model 747-400 series airplanes failed to
deploy properly. Investigation revealed that the apparent cause of one
of these failures has been attributed to the improper gluing method
used during the manufacturing process. The FAA finds this situation to
be isolated to a specific builder and limited to only seven units in
which only one unit failed.
However, further investigation has revealed that, during the
initial deployment stages of door 5 evacuation slide/raft, the
inflation bottle bag can apply adverse loads to both the forward side
bottle hanger strap and the lower girt attachment on the forward side
of this evacuation slide/raft. Such adverse loads could pull the center
girt attachment partially loose at the forward side, or could tear the
lower inflation tube assembly at the forward edge of the center girt.
The cause of such adverse loads has been attributed to the geometry of
this particular evacuation slide/raft. This condition, if not
corrected, could result in failure of door 5 evacuation slide/raft to
deploy properly, which could contribute to injury of passengers on the
slide, and could delay or impede the evacuation of passengers during an
emergency.
Explanation of Relevant Service Information
The FAA has reviewed and approved BFGoodrich Service Bulletin
7A1469-25-283, dated November 6, 1995, which describes procedures for
modification of door 5 evacuation slide/rafts. The modification
involves replacing the bottle support straps of door 5 with new support
straps, relocating these straps, and directly lacing them to the center
girt attachment. Accomplishment of the modification will eliminate
bonded attachments from the load path and prevent damage to the slide/
raft fabric.
Explanation of the Requirements of the 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 modification of the door 5 evacuation slide/
rafts. The actions would be required to be accomplished in accordance
with the alert service bulletin described previously.
Explanation of the Applicability of the Proposed Rule
Operators should note that the applicability of this proposed rule
affects Boeing Model 747-400 series airplanes that are equipped with
certain BFGoodrich escape slide/rafts. The FAA's general policy is
that, when an unsafe condition results from the installation of an
appliance or other item that is installed in only one particular make
and model of aircraft, the AD is issued so that it is applicable to the
aircraft, rather than the item. The reason is simple: Making the AD
applicable to the airplane model on which the item is installed ensures
that operators of those airplanes will be notified directly of the
unsafe condition and the action required to correct it. While it is
assumed that an operator will know the models of airplanes that it
operates, there is a potential that the operator will not know or be
aware of specific items that are installed on its airplanes. It is for
this reason that this proposed AD would be applicable to Model 747-
400's rather than to the BFGoodrich escape slide/rafts. Additionally,
calling out the airplane model as the subject of the AD prevent
``unknowing non-compliance'' on the part of the operator.
The FAA recognizes that there are situations when an unsafe
condition exists in an item that is installed in many different
aircraft. In those cases, the FAA considers it impractical to issue
AD's against each aircraft; in fact, many times, the exact models and
number of aircraft on which the item is installed may not be known.
Therefore, in those situations, the AD is issued so that it is
applicable to the item; furthermore, those AD's usually indicate that
the item is known to be installed on, but not limited to, various
aircraft models.
Cost Impact
The FAA estimates that 150 BFGoodrich evacuation slide/rafts
installed on 75 Boeing Model 747-400
[[Page 18707]]
series airplanes (2 slides per airplane) of U.S. registry would be
affected by this proposed AD, that it would take approximately 1 work
hour per slide to accomplish the proposed actions, and that the average
labor rate is $60 per work hour. Required parts would cost
approximately $84 per slide. Based on these figures, the cost impact of
the proposed AD on U.S. operators is estimated to be $21,600, or $144
per slide.
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.
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 USC 106(g), 40113, 44701.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by adding the following new
airworthiness directive:
Boeing: Docket 95-NM-218-AD.
Applicability: Model 747-400 series airplanes equipped with
BFGoodrich Evacuation Slide/Rafts at door 5; having slide/raft assembly
part number 7A1469-1, -2, -3, -4, -7, -8, -9, -10, -11, or -12 (all
unit serial numbers); certificated in any category.
Note 1: This AD applies to each airplane identified in the
preceding applicability provision, regardless of whether it has been
otherwise 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 (b) 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 failure of the door 5 evacuation slide/raft to deploy
properly, which could contribute to injury of passengers on the
slide and could delay or impede the evacuation of passengers during
an emergency, accomplish the following:
(a) Within 36 months after the effective date of this AD, modify
the door 5 evacuation slide/raft in accordance with BFGoodrich
Service Bulletin 7A1469-25-283, dated November 6, 1995.
Note 2: Modification previous to the effective date of this AD
in accordance with Boeing Alert Service Bulletin 747-25A3096, which
references BFGoodrich Service Bulletin 7A1469-25-283, dated November
6, 1995, is considered acceptable for compliance with the
modification requirements of paragraph (a) of this AD.
(b) 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, Los Angeles Aircraft Certification
Office (ACO), FAA, Transport 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, Los Angeles ACO.
Note 3: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Los Angeles ACO.
(c) 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 April 23, 1996.
S.R. Miller,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 96-10506 Filed 4-26-96; 8:45 am]
BILLING CODE 4910-13-P
