[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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