[Federal Register Volume 63, Number 106 (Wednesday, June 3, 1998)]
[Proposed Rules]
[Pages 30150-30152]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-14610]


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Proposed Rules
                                                Federal Register
________________________________________________________________________

This section of the FEDERAL REGISTER contains notices to the public of 
the proposed issuance of rules and regulations. The purpose of these 
notices is to give interested persons an opportunity to participate in 
the rule making prior to the adoption of the final rules.

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Federal Register / Vol. 63, No. 106 / Wednesday, June 3, 1998 / 
Proposed Rules

[[Page 30150]]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-128-AD]
RIN 2120-AA64


Airworthiness Directives; Airbus Model A310 and A300-600 Series 
Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the supersedure of an existing 
airworthiness directive (AD), applicable to all Airbus Model A310 and 
A300-600 series airplanes, that currently requires a revision of the 
Airplane Flight Manual that warns the flightcrew of certain 
consequences associated with overriding the autopilot when it is in the 
pitch control axis. It also requires modification of certain flight 
control computers, and a modification to the autopilot. For certain 
airplanes, that AD also requires repetitive operational testing of the 
modified autopilot to determine if the disconnect function operates 
properly, and repair, if necessary. This action would add a new 
requirement to accomplish those repetitive operational tests on other 
airplanes. This proposal is prompted by issuance of mandatory 
continuing airworthiness information by a foreign civil airworthiness 
authority. The actions specified by the proposed AD are intended to 
prevent an out-of-trim condition between the trimmable horizontal 
stabilizer and the elevator, which could result in severely reduced 
controllability of the airplane.

DATES: Comments must be received by July 6, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 98-NM-128-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 Airbus Industrie, 1 Rond Point Maurice Bellonte, 31707 
Blagnac Cedex, France. This information may be examined at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington.

FOR FURTHER INFORMATION CONTACT: Norman B. Martenson, Manager, 
International Branch, ANM-116, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-2110; fax (425) 227-1149.

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 98-NM-128-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. 98-NM-128-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    On August 25, 1997, the FAA issued AD 97-18-09, amendment 39-10119 
(62 FR 45710, August 29, 1997), applicable to all Airbus Model A310 and 
A300-600 series airplanes, to require a revision to the Airplane Flight 
Manual (AFM) that warns the flightcrew of certain consequences 
associated with overriding the autopilot when it is in the pitch 
control axis, modification of certain flight control computers (FCC), 
and modification of the autopilot, which would enable the flightcrew to 
disconnect the autopilot when direct force is applied to the control 
column, regardless of its mode and the altitude of the airplane. That 
AD also requires repetitive operational testing of the modified 
autopilot to determine if the disconnect function operates properly, 
and repair, if necessary. That action was prompted by the results of an 
FAA review of the requirements of an earlier AD. The requirements of 
that AD are intended to prevent an out-of-trim condition between the 
trimmable horizontal stabilizer and the elevator, which could result in 
severely reduced controllability of the airplane.

Actions Since Issuance of Previous Rule

    Since the issuance of AD 97-18-09, the Direction Generale de 
l'Aviation Civile (DGAC), which is the airworthiness authority for 
France, has issued French airworthiness directive 97-373-237(B), dated 
December 3, 1997, which specifies that Airbus Model A310 and A300-600 
series airplanes on which the modification of the autopilot (reference 
Airbus Modification 11454) has been accomplished during production 
should be subject to the same repetitive operational tests required to 
be performed on Airbus Model A310 and A300-600 series airplanes 
modified in accordance with Airbus Service Bulletin A310-22-2044, 
Revision 1, or A300-22-6032, Revision 1, both dated January 8, 1997 
(which were referenced by AD 97-18-09 as the appropriate sources of 
service information).
    In light of the criticality of the unsafe condition (an out-of-trim 
condition between the trimmable horizontal stabilizer and the elevator, 
which could

[[Page 30151]]

severely reduce controllability of the airplane), modification of the 
autopilot alone may not provide the degree of safety assurance 
necessary for the transport airplane fleet. Therefore, repetitive 
operational testing of the modified autopilot to determine if the 
disconnect function operates properly is necessary to ensure long term 
continued operational safety, whether the modification was installed 
during production or in accordance with AD 97-18-09.

FAA's Conclusions

    These airplane models are manufactured in France and are type 
certificated for operation in the United States under the provisions of 
section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and 
the applicable bilateral airworthiness agreement. Pursuant to this 
bilateral airworthiness agreement, the DGAC has kept the FAA informed 
of the situation described above. The FAA has examined the findings of 
the DGAC, reviewed all available information, and determined that AD 
action is necessary for products of this type design that are 
certificated for operation in the United States.

Explanation of Requirements of Proposed Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other airplanes of the same type design registered 
in the United States, the proposed AD would supersede AD 97-18-09 to 
continue to require a revision to the Limitations Section of the AFM 
that warns the flightcrew of certain consequences associated with 
overriding the autopilot when it is in the pitch control axis; 
modification of certain FCC's; modification of the autopilot and 
removal of the revision to the AFM once the modification has been 
accomplished; repetitive operational testing of the modified autopilot 
to determine if the disconnect function operates properly; and repair, 
if necessary.
    This proposed AD would add a new requirement for accomplishment of 
the same repetitive operational tests on Airbus Model A310 and A300-600 
series airplanes that received the modification to the autopilot during 
production.

Cost Impact

    There are approximately 94 airplanes of U.S. registry that would be 
affected by this proposed AD.
    The AFM revision that was required previously by AD 96-08-07 and 
retained in this AD, takes 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 of the currently required AFM revision 
on U.S. operators is estimated to be $5,640, or $60 per airplane.
    The modification of certain FCC's that was required previously by 
AD 96-08-07 and retained in this AD, takes approximately 1 work hour 
per airplane to accomplish, at an average labor rate of $60 per work 
hour. Required parts will be supplied by the manufacturer at no cost to 
operators. Based on these figures, the cost impact of the currently 
required modification of FCC's on U.S. operators is estimated to be 
$5,640, or $60 per airplane.
    The modification of the autopilot that was required previously by 
AD 97-18-09 and retained in this AD, takes approximately 25 work hours 
per airplane to accomplish, at an average labor rate of $60 per work 
hour. Required parts cost approximately $1,578 per airplane. Based on 
these figures, the cost impact of the currently required modification 
of the autopilot on U.S. operators is estimated to be $289,332, or 
$3,078 per airplane.
    The operational test that was required previously by AD 97-18-09 
and retained in this AD, takes approximately 7 work hours per airplane, 
per test cycle, to accomplish, at an average labor rate of $60 per work 
hour. Based on these figures, the cost impact of the currently required 
operational test requirement on U.S. operators is estimated to be 
$39,480, or $420 per airplane, per test cycle.
    The cost impact figures discussed above are based on assumptions 
that no operator has yet accomplished any of the current or 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 U.S.C. 106(g), 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by removing amendment 39-10119 (62 FR 
45710, August 29, 1997), and by adding a new airworthiness directive 
(AD), to read as follows:

Airbus Industrie: Docket 98-NM-128-AD. Supersedes AD 97-18-09, 
Amendment 39-10119.

    Applicability: All Model A310 and A300-600 series airplanes, 
certificated in any category.

    Note 1: 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 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 (f) 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 an out-of-trim condition between the trimmable 
horizontal stabilizer and the elevator, which could result in 
severely reduced controllability of the airplane, accomplish the 
following:

[[Page 30152]]

RESTATEMENT OF ACTIONS REQUIRED BY AD 96-08-07, AMENDMENT 39-9573

    (a) Within 10 days after May 23, 1996 (the effective date of AD 
96-08-07, amendment 39-9573), revise the Limitations Section of the 
FAA-approved Airplane Flight Manual (AFM) to include the information 
contained in paragraph (a)(1) or (a)(2) of this AD, as applicable. 
This may be accomplished by inserting a copy of this AD in the AFM. 
The AFM limitation required by AD 94-21-07, amendment 39-9049, may 
be removed following accomplishment of the requirements of this 
paragraph.
    (1) For airplanes on which the flight control computers (FCC) 
have not been modified in accordance with the requirements of 
paragraph (b) of this AD:
    ``Overriding the autopilot (AP) in pitch axis does not cancel 
the AP autotrim when LAND TRACK mode [green LAND on both Flight Mode 
Annunciators (FMA)] or GO-AROUND mode is engaged. In these modes, if 
the pilot counteracts the AP, the autotrim will trim against pilot 
input. This could lead to a severe out-of-trim situation in a 
critical phase of flight.''
    (2) For airplanes on which the FCC's have been modified in 
accordance with the requirements of paragraph (b) of this AD:
    ``Overriding the autopilot (AP) in pitch axis does not cancel 
the AP autotrim when LAND TRACK mode (green LAND on both FMA's) is 
engaged, or GO-AROUND mode is engaged below 400 feet radio altitude 
(RA). In these modes, if the pilot counteracts the AP, the autotrim 
will trim against pilot input. This could lead to a severe out-of-
trim situation in a critical phase of flight.''

RESTATEMENT OF ACTIONS REQUIRED BY AD 94-21-07, AMENDMENT 39-9049

    (b) For airplanes equipped with FCC's having either part number 
(P/N) B470ABM1 (for Model A310 series airplanes) or B470AAM1 (for 
Model A300-600 series airplanes): Within 60 days after November 2, 
1994 (the effective date of AD 94-21-07, amendment 39-9049), modify 
the FCC's in accordance with Airbus Service Bulletin A310-22-2036, 
dated December 14, 1993 (for Model A310 series airplanes), or Airbus 
Service Bulletin A300-22-6021, Revision 1, dated December 24, 1993 
(for Model A300-600 series airplanes), as applicable.
    (c) As of November 2, 1994, no person shall install a FCC having 
either P/N B470ABM1 or B470AAM1 on any airplane.

RESTATEMENT OF ACTIONS REQUIRED BY AD 97-18-09, AMENDMENT 39-10119

    (d) For airplanes on which Modification No. 11454 [reference 
Airbus Service Bulletin A310-22-2044, Revision 1 (for Model A310 
series airplanes) or Airbus Service Bulletin A300-22-6032, Revision 
1 (for Model A300-600 series airplanes)] has not been installed: 
Accomplish paragraphs (d)(1), (d)(2)(i), and (d)(2)(ii) of this AD.
    (1) Within 24 months after October 3, 1997 (the effective date 
of AD 97-18-09, amendment 39-10119), modify the autopilot in 
accordance with Airbus Service Bulletin A310-22-2044, Revision 1, 
dated January 8, 1997 (for Model A310 series airplanes), or Service 
Bulletin A300-22-6032, Revision 1, dated January 8, 1997 (for Model 
A300-600 series airplanes), as applicable. The requirements of 
paragraph (a) of AD 95-25-09, amendment 39-9455, if applicable, must 
be accomplished prior to or at the same time the requirements of 
this paragraph are accomplished.
    (2) Prior to further flight following accomplishment of 
paragraph (d)(1) of this AD:
    (i) Remove the AFM revisions required by paragraph (a) of this 
AD; and
    (ii) Perform an operational test of this autopilot disconnect 
feature to determine that it operates properly, in accordance with 
Airbus Service Bulletin A310-22-2047, dated July 16, 1996 (for Model 
A310 series airplanes), or Service Bulletin A300-22-6035, dated July 
16, 1996 (for Model A300-600 series airplanes), as applicable. If 
any discrepancy is detected, prior to further flight, repair it in 
accordance with the applicable service bulletin. Repeat this test 
thereafter at intervals not to exceed 18 months.

NEW ACTIONS REQUIRED BY THIS AD

    (e) For airplanes on which Modification No. 11454 was installed 
during production: Within 18 months after the date of manufacture of 
the airplane, or within 6 months after the effective date of this 
AD, whichever occurs later, accomplish the actions specified in 
paragraph (d)(2)(ii) of this AD.
    (f) 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, International Branch, ANM-116, 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, International 
Branch, ANM-116.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the International Branch, ANM-116.

    (g) 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.

    Note 3: The subject of this AD is addressed in French 
airworthiness directive 97-373-237(B), dated December 3, 1997.

    Issued in Renton, Washington, on May 27, 1998.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 98-14610 Filed 6-2-98; 8:45 am]
BILLING CODE 4910-13-U