[Federal Register Volume 59, Number 79 (Monday, April 25, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-9870]
[[Page Unknown]]
[Federal Register: April 25, 1994]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 93-NM-63-AD]
Airworthiness Directives; Airbus Model A320 Series Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Supplemental notice of proposed rulemaking; reopening of
comment period.
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SUMMARY: This document revises an earlier proposed airworthiness
directive (AD), applicable to certain Airbus Model A320 series
airplanes, that would have required revising the Limitations Section of
the Airplane Flight Manual (AFM) to prohibit the airplane from extended
overwater operations. That proposal was prompted by a report that,
during an emergency evacuation demonstration, the lanyard connecting
the survival kit to the slide/raft became entangled on the girt bar
indicator mechanism, and subsequently prevented an exit door from
opening fully to a locked position. This action revises the proposed
rule by deleting the previously proposed AFM limitation; and requiring
either the removal of the girt bar visual indicator brackets on
passenger exit doors or modification of the lanyard. The actions
specified by this proposed AD are intended to prevent the lanyard from
becoming entangled and interfering with proper opening of the exit
door, a situation which could impede the successful evacuation of
passengers through the door during an overwater operation where
ditching is required.
DATES: Comments must be received by May 25, 1994.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 93-NM-63-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. -
This information may be examined at the FAA, Transport Airplane
Directorate, 1601 Lind Avenue SW., Renton, Washington.
FOR FURTHER INFORMATION CONTACT: Stephen Slotte, Aerospace Engineer,
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate,
1601 Lind Avenue SW., Renton, Washington 98055-4056; telephone (206)
227-2797; fax (206) 227-1320.
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 93-NM-63-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. 93-NM-63-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
Discussion
A proposal to amend part 39 of the Federal Aviation Regulations to
add an airworthiness directive (AD), applicable to all Airbus Model
A320 series airplanes, was published as a notice of proposed rulemaking
(NPRM) in the Federal Register on July 27, 1993 (58 FR 40077). That
NPRM would have required revising the Limitations Section of the FAA-
approved Airplane Flight Manual (AFM) to prohibit the airplane from
extended overwater operations. That action also would have provided for
an optional terminating action of modification of the lanyard that
attaches the overwater survival kit to the slide/raft; once
accomplished, the AFM limitation could be removed.
NPRM was prompted by a report that, during an emergency evacuation
demonstration, the subject lanyard became entangled on the girt bar
indicator mechanism, and subsequently prevented an exit door from
opening fully to a locked position. That condition, if not corrected,
could impede the successful evacuation of passengers through the door
during an overwater operation where ditching is required. -
Since the issuance of that NPRM, the FAA has reconsidered its
position on certain of the proposed requirements, based on the comments
received in response to the notice. -
One commenter, Airbus Industrie (Airbus), questions the
justification for the proposed rule, and requests that the FAA withdraw
it . Airbus contends that, according to the international bilateral
airworthiness agreements, the responsibility to determine the existence
and extent of an unsafe condition with respect to any reported incident
lies within the jurisdiction of the primary authority, in this case,
the Direction Generale de l'Aviation Civile (DGAC), which is the
airworthiness authority for France. Airbus states that the DGAC made a
decision not to issue a French airworthiness directive to mandate a
modification of the airplane design because (1) the slide was correctly
deployed during the incident upon which this proposed rule is based;
and (2) although the door did not go to the fully-open position during
that incident, it did not interfere with the passenger flow during
evacuation. Airbus also states that the door will remain in the not-
fully-open position until it is pushed to the fully-open position by
the assisting cylinder, which is maintained pressurized until the door
reaches the fully-open and locked position. During the incident, the
door did not initially go to the fully-open position because the
overwater survival kit lanyard was caught by the visual indicator
bracket and became entangled between the door and the fuselage. When
the crew untangled the lanyard, the door went into the fully-opened and
locked position. -
The FAA does not concur with the commenter's suggestion to withdraw
the proposal. While the United States and France observe the provisions
of the bilateral airworthiness agreement, it remains the responsibility
of the FAA to monitor and maintain the continuing airworthiness of
U.S.-type certificated and -registered airplanes. The bilateral
airworthiness agreements do not restrict the FAA from issuing AD's
based upon its own finding of an unsafe condition, regardless of the
decision made by another airworthiness authority relative to the same
subject. The FAA has examined the analyses of the evacuation
demonstration, has reviewed all other available data, and has
determined that an unsafe condition exists with regard to problem of
the lanyard becoming entangled on the girt bar indicator mechanism and
preventing the exit door from opening fully to a locked position.
Therefore, the FAA has determined that AD action is necessary for
airplanes of this type design that are certificated for operation in
the United States. -
One commenter requests that the applicability of the proposed rule
be limited to only those Model A320 series airplanes that are equipped
with slide/raft evacuation systems eligible for overwater operations.
The commenter contends that the scenario for the occurrence of the
addressed unsafe condition would not apply to those airplanes without
the slide/raft evacuation systems; therefore, they should be exempt
from the proposed rule. The FAA concurs and has revised the
applicability of this supplemental NPRM accordingly. -
Two commenters request that the proposal be revised to include the
installation of Modification 23605, described in Airbus Service
Bulletin A320-25-1109, dated April 20, 1993, as an acceptable
modification that would permit the removal of the proposed limitation
in the AFM (prohibiting extended overwater operations). This
modification entails replacing the existing girt bar indicator bracket
with a red arrow placard on the slide/raft decorative covers. The FAA
does not concur totally with the commenters' request. The FAA has
evaluated the referenced modification and has found that, while removal
of the brackets will prevent possible interference between the
overwater survival kit lanyard and the slide/raft decorative cover, the
placards do not provide for an acceptable means of girt bar position
indication. -
The FAA has reviewed the current design of the visual girt bar
position indicator brackets (plates) and finds that, as designed and
installed, these brackets contribute to the problem of lanyard
entanglement that leads to the unsafe condition addressed by this AD.
In light of this, the FAA has revised this proposed rule to require
that, in lieu of modifying the lanyard, operators may remove the girt
bar visual indicator brackets from all doors that are equipped with
them. (The girt bar position/arming indicator in the cockpit, however,
would be unaffected by this action; it would remain as a source to
obtain positive indication of the position of the girt bar.) The FAA
considers that this proposed action will be as effective in addressing
the unsafe condition and as timely to accomplish as the modificatin of
the lanyard. Additionally, since removal of the brackets or
modificaiton of the lanyard will eliminate the problem of entanglement
of the lanyard and the subsequent problems of opening the exit door
properly, the FAA has deleted the previously proposed requirement that
would have prohibited extended overwater operation of the affected
airplanes.
This is considered interim action. Airbus Industrie has advised the
FAA that it is developing an alternative method of girt bar position
indication that will not entail a design feature that would contribute
to the addressed problem of lanyard entanglement. Once this
modification is developed, approved, and available, the FAA may
consider further rulemaking. -
Since the change described above expands 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. -
The FAA estimates that 59 Model A320 airplanes of U.S. registry
would be affected by this proposed AD.
Accomplishment of the removal of the girt bar visual indicator
brackets would take approximately 1 work hour per airplane, at an
average labor rate of $55 per work hour. Based on these figures, the
total cost impact of this proposed removal action on U.S. operators who
elect to accomplish it is estimated to be $55 per airplane.
The time necessary to accomplish the modification of the lanyard
may vary from operator to operator, depending upon the design submitted
for approval by the FAA. However, the FAA estimates that a typical
modification would require an average of 2 work hours to accomplish, at
an average labor rate of $55 per work hour. Based on these figures, the
total cost impact of this proposed modification action on U.S.
operators who elect to accomplish it is estimated to be $110 per
airplane.
Based on the figures discussed above, the total cost impact of this
proposed AD on U.S. operators is estimated to be between $3,245 and
$6,490. This total cost impact figure 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 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 14
CFR part 39 of the Federal Aviation Regulations as follows:
PART 39--AIRWORTHINESS DIRECTIVES -
1. The authority citation for part 39 continues to read as follows:
Authority: 49 U.S.C. App. 1354(a), 1421 and 1423; 49 U.S.C.
106(g); and 14 CFR 11.89.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by adding the following new
airworthiness directive:
Airbus Industrie: Docket 93-NM-63-AD.
Applicability: Model A320 series airplanes equipped with slide/
raft evacuation systems, certificated in any category. -
Compliance: Required as indicated, unless accomplished
previously.
To prevent the lanyard from becoming entangled on the girt bar
indicator mechanism, if passengers are required to utilize the exit
door during extended overwater operations where ditching may be
required, accomplish the following: -
(a) Within 90 days after the effective date of this AD,
accomplish the requirements of either paragraph (a)(1) or (a)(2) of
this AD:
(1) Remove the girt bar visual indicator brackets (plates) from
all passenger exit doors that are so equipped. Or
(2) Modify the lanyard that attaches the survival kit to the
slide/raft so that it does not become entangled on the girt bar
indicator mechanism, in accordance with a method approved by the
Manager, Standardization Branch, ANM-113, FAA, Transport Airplane
Directorate.-
(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, Standardization Branch, ANM-113,
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,
Standardization Branch, ANM-113.
Note: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Standardization Branch, ANM-113.
(c) Special flight permits may be issued in accordance with
Secs. 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 19, 1994.
S.R. Miller,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 94-9870 Filed 4-25-94; 8:45 am]
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