[Federal Register Volume 61, Number 170 (Friday, August 30, 1996)]
[Rules and Regulations]
[Pages 45878-45880]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-22010]
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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 95-NM-138-AD; Amendment 39-9728; AD 96-18-04]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 737-300, -400, and -500
Series Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule.
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SUMMARY: This amendment supersedes two existing airworthiness
directives (AD), applicable to certain Boeing Model 737-300, -400, and
-500 series airplanes, that currently require modification of the
packing and slide containers of the escape slide, and repetitive
inspections of the velcro girt retaining straps of the escape slides at
the forward door. The existing AD's were prompted by reports of slide
girt material interfering with the girt bar stowage brackets during
door opening. This new amendment requires the installation of a new
modification, which constitutes terminating action for the repetitive
inspection requirements. The actions specified by this amendment are
intended to prevent failure or interference of opening of the forward
doors, which could delay or impede the evacuation of passengers during
an emergency.
DATES: Effective October 4, 1996.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of October 4, 1996.
ADDRESSES: The service information referenced in this AD may be
obtained from Air Cruisers Company, P.O. Box 180, Belmar, New Jersey
07719-0180; and Boeing Commercial Airplane Group, P.O. Box 3707,
Seattle, Washington 98124-2207. This information may be examined at the
Federal Aviation Administration (FAA), Transport Airplane Directorate,
Rules Docket, 1601 Lind Avenue, SW., Renton, Washington; or at the
Office of the Federal Register, 800 North Capitol Street, NW., suite
700, Washington, DC.
FOR FURTHER INFORMATION CONTACT: Roy Boffo, Aerospace Engineer,
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office,
1601 Lind Avenue, SW., Renton, Washington; telephone (206) 227-2780;
fax (206) 227-1181.
SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal
Aviation Regulations (14 CFR part 39) by superseding both AD 88-07-07
[amendment 39-5884 (53 FR 9864, March 28, 1988)] and AD 91-24-04
[amendment 39-8090 (56 FR 57588, November 13, 1991)] was published as a
Notice of Proposed Rulemaking (NPRM) in the Federal Register on January
19, 1996 (61 FR 1291). Both of the existing AD's are applicable to
various Boeing Model 737 series airplanes.
The NPRM proposed to continue to require modification of the escape
slide packing and slide containers, which was required previously by AD
88-07-07. The NPRM also proposed to continue to require repetitive
inspections of the velcro girt retaining straps at the forward door of
the escape slides, which was required previously by AD 91-24-04.
Additionally, the NPRM proposed to require modification of the escape
slide girts, which would constitute terminating action for the
repetitive inspection requirements.
Interested persons have been afforded an opportunity to participate
in the making of this amendment. Due consideration has been given to
the comments received.
Support for the Proposal
Two commenters support the proposal.
Request To Allow Removal of Placard
One commenter requests that the proposal be revised to allow
operators to remove the velcro straps attach points and placard on the
slide compartment cover that were installed as part of the modification
required by AD 88-07-07. The commenter adds that some operators have
already removed these items when they installed a modification that was
approved as an alternative method of compliance with the repetitive
inspections required by AD 91-24-04.
The FAA concurs. Once the terminating modification required by
paragraph (c) of this final rule is installed, the velcro straps (and
their attach points) are no longer necessary, and the placard may be
confusing if it remains on the slide compartment. The FAA has revised
paragraph (c) of the final rule to indicate that these items should be
removed.
Request To Continue Approval of Previous Alternative Methods of
Compliance
Several commenters request that the proposal be revised to specify
that alternative methods of compliance (AMOC) approved previously by
the FAA for AD 91-24-04, continue to be considered approved for this
new AD. Specifically, three commenters point out that the FAA had
previously approved, as an AMOC, the accomplishment of the modification
described in Air Cruisers Service Bulletin S.B. 103-25-23 as
terminating action for the repetitive inspections required by AD 91-24-
04. These commenters request that the proposed rule likewise cite this
service bulletin as an alternative terminating action.
The FAA does not concur. The modification described in Air Cruisers
Service Bulletin S.B. 103-25-23 entails adding placards to the escape
slide girt (that depict the proper stowed configuration of the girt)
and removing the velcro straps that were required to be installed by AD
88-07-07. That modification, however, is reliant upon flight attendant
procedures to correctly route the escape slide girt. Several recent
ramp inspections of in-service airplanes have revealed that the girt
material is still being misrouted, even with the placard installed. In
light of this, the FAA has determined that the modification in that Air
Cruisers service bulletin does not fully address the safety concern and
is not as effective as the modification that is required by this new
AD.
The modification specified in this final rule (which is described
in Air Cruisers Service Bulletin S.B. 103-25-19) involves removing the
existing girt; bonding on the girt attachments; installing a detachable
girt; rigging a painter/mooring line; and bonding a placard to the
slide assembly and reidentifying it. This modification will improve the
operation of the escape slide of the forward entry and service doors,
and will eliminate the need to rely on human factors associated with
[[Page 45879]]
ensuring that girt material is stowed properly.
Request To Allow Use of Revised Service Documents
One commenter requests that the proposal be revised to allow
operators to install the terminating modification, proposed in
paragraph (c), in accordance with various revisions of Air Cruisers
Service Bulletin S.B. 103-25-19. The commenter points out that the
service bulletin has been revised several times since the original
version was released in May 1992.
The FAA concurs. The FAA has reviewed and approved all revisions of
Air Cruisers Service Bulletin S.B. 103-25-19 through Revision 7, dated
April 18, 1996. The various revisions are essentially identical, except
for certain minor editorial changes. The FAA has revised paragraph (c)
of the final rule to indicate that accomplishing the modification in
accordance with any of these revisions is acceptable for compliance
with that paragraph.
Conclusion
After careful review of the available data, including the comments
noted above, the FAA has determined that air safety and the public
interest require the adoption of the rule with the changes previously
described. The FAA has determined that these changes will neither
increase the economic burden on any operator nor increase the scope of
the AD.
Cost Impact
There are approximately 1,572 Model 737-300, -400, and -500 series
airplanes, equipped with Air Cruisers forward door escape slide of the
affected design in the worldwide fleet. The FAA estimates that 663
airplanes of U.S. registry will be affected by this proposed AD.
The actions that are currently required by AD 88-07-07 take
approximately 9 work hours per airplane to accomplish, at an average
labor rate of $60 per work hour. Required parts cost approximately $76
per airplane. Based on these figures, the cost impact on U.S. operators
(175 airplanes) of the actions currently required is estimated to be
$107,800, or $616 per airplane.
The actions that are currently required by AD 91-24-04 take
approximately 1 work hour per airplane to accomplish, at an average
labor rate of $60 per work hour. Based on these figures, the cost
impact on U.S. operators (439 airplanes) of the actions currently
required is estimated to be $26,340, or $60 per airplane, per
inspection cycle.
The terminating modification that is required by this new AD will
take approximately 6 work hours per airplane to accomplish, at an
average labor rate of $60 per work hour. Required parts cost
approximately $1,800 per airplane. Based on these figures, the cost
impact on U.S. operators of the new modification requirements of this
AD is estimated to be $1,432,080, or $2,160 per airplane.
The cost impact figures discussed above are based on assumptions
that no operator has yet accomplished any of the 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 adopted herein will 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 final
rule does not have sufficient federalism implications to warrant the
preparation of a Federalism Assessment.
For the reasons discussed above, I certify that this action (1) is
not a ``significant regulatory action'' under Executive Order 12866;
(2) is not a ``significant rule'' under DOT Regulatory Policies and
Procedures (44 FR 11034, February 26, 1979); and (3) 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 final evaluation has been prepared for this action
and it is contained in the Rules Docket. A copy of it may be obtained
from the Rules Docket at the location provided under the caption
ADDRESSES.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
Accordingly, pursuant to the authority delegated to me by the
Administrator, the Federal Aviation Administration amends 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 removing amendments 39-5884 (53 FR
9864, March 28, 1988) and 39-8090 (56 FR 57588, November 13, 1991), and
by adding a new airworthiness directive (AD), amendment 39-9728, to
read as follows:
96-18-04 Boeing: Amendment 39-9728. Docket 95-NM-138-AD. Supersedes
AD 88-07-07, amendment 39-5884; and supersedes AD 91-24-04,
amendment 39-8090.
Applicability: Model 737-300, -400, and -500 series airplanes,
line numbers up to and including 2211; equipped with Air Cruisers
forward door escape slides as listed in Air Cruisers Company Service
Bulletin S.B. 103-25-19, Revison 7, dated April 18, 1996;
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 (d) 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 or interference of opening of the forward
doors, which could delay or impede the evacuation of passengers
during an emergency, accomplish the following:
(a) Within 30 days after December 17, 1991 (the effective date
of 91-24-04, amendment 39-8090), establish operating procedures,
approved by the FAA Principal Maintenance Inspector (PMI), for the
forward doors to include the requirements specified in paragraphs
(a)(1), (a)(2), and (a)(3) of this AD; and thereafter, comply with
those procedures until the modification required by paragraph (c) of
this AD is accomplished. The procedures required by paragraphs
(a)(1) and (a)(2) of this AD must be accomplished by qualified and
trained mechanics. The procedures required by paragraph (a)(3) may
be accomplished by qualified and trained members of the flightcrew
or cabin crew. The training program to implement the procedures
required by this paragraph must be approved by the FAA PMI. Methods
for documentation of compliance with the following procedures must
be approved by the FAA PMI.
(1) Prior to the next flight after December 17, 1991, and
thereafter at intervals not to exceed 200 flight hours, inspect the
condition of the girt retaining straps at the forward doors.
(2) Prior to further flight after December 17, 1991, replace
worn or aged velcro whose grip
[[Page 45880]]
strength will no longer hold the girt retaining straps in position.
(3) Prior to the next flight after December 17, 1991, and
thereafter prior to each flight, inspect the routing of the girt
retaining straps at the forward doors, and reroute straps that are
found not to be routed in accordance with the placarded instructions
installed in accordance with AD 88-07-07, amendment 39-5885, on the
inboard face of the slide compartment.
(b) For Model 737-300 series airplanes: Within 6 months after
May 9, 1988 (the effective date of AD 88-07-07, amendment 39-5885),
modify the escape slide packing and slide containers in accordance
with Boeing Alert Service Bulletin 737-25A1221, dated December 17,
1987, or Revision 1, dated June 2, 1988. This modification must be
accomplished prior to or in conjunction with accomplishment of the
requirements of paragraph (c) of this AD.
(c) Within 36 months after the effective date of this AD, modify
the escape slide girts in accordance with Air Cruisers Company
Service Bulletin S.B. 103-25-19, Revision 7, dated April 18, 1996.
Accomplishment of the modification constitutes terminating action
for the repetitive inspections required by paragraph (a) of this AD.
Once this modification is installed, the placard and velcro straps
(and their attach points) required by the modification specified in
paragraph (b) of this AD may be removed.
Note 2: Accomplishment of this modification prior to the
effective date of this AD in accordance with previous revisions of
Air Cruisers Company Service Bulletin S.B. 103-25-19 is considered
acceptable for compliance with the requirements of this paragraph.
(d) 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, 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, Seattle ACO.
Note 3: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Seattle ACO.
(e) 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.
(f) Except as indicated in NOTE 2 of this AD, the terminating
modification shall be done in accordance with Air Cruisers Company
Service Bulletin S.B. 103-25-19, Revision 7, dated April 18, 1996.
This incorporation by reference was approved by the Director of the
Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part
51. Copies may be obtained from Air Cruisers Company, P.O. Box 180,
Belmar, New Jersey 07719-0180. Copies may be inspected at the FAA,
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton,
Washington; or at the Office of the Federal Register, 800 North
Capitol Street, NW., suite 700, Washington, DC.
(g) This amendment becomes effective on Ocotber 4, 1996.
Issued in Renton, Washington, on August 21, 1996.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 96-22010 Filed 8-29-96; 8:45 am]
BILLING CODE 4910-13-U
