[Federal Register Volume 61, Number 135 (Friday, July 12, 1996)]
[Proposed Rules]
[Pages 36664-36667]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-17741]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 94-NM-222-AD]
RIN 2120-AA64


Airworthiness Directives; Airbus Model A310 and A300-600 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 A310 and A300-600 
series airplanes, that would have required repetitive Tap Test 
inspections to detect debonding of the elevator skins, and corrective 
actions, if necessary. That proposal was prompted by a report that a 
debonded area of the upper skin of an elevator had been discovered 
during a visual inspection. This action revises the proposed rule by 
replacing the Tap Test inspections with inspections using a 
thermographic technique. This action also provides for replacement of 
the elevators with new or modified elevators, which, if accomplished, 
terminates the requirements of the AD. The actions specified by this 
proposed AD are intended to prevent the presence of water in the 
elevator, which could cause debonding of the elevator skins and, 
consequently, could adversely affect the structural integrity of the 
elevator.

DATES: Comments must be received by August 14, 1996.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 94-NM-222-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: Charles Huber, Aerospace Engineer, 
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206) 
227-2589; fax (206) 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 94-NM-222-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. 94-NM-222-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    A proposal to amend part 39 of the Federal Aviation Regulations (14 
CFR part 39) to add an airworthiness directive (AD), applicable to 
certain Airbus Model A310 and A300-600 series airplanes, was published 
as a notice of proposed rulemaking (NPRM) in the Federal Register on 
February 8, 1995 (60 FR 7485). That NPRM would have required repetitive 
Tap Test inspections to detect debonding of the elevator skins, and 
corrective actions, if necessary. Additionally, that NPRM would have 
required repetitive thermographic inspections of the elevator to detect 
trapped water if certain amounts of debonding are detected. That NPRM 
was prompted by

[[Page 36665]]

a report that a debonded area of the upper skin of an elevator had been 
discovered during a visual inspection. That condition, if not 
corrected, could result in the presence of water in the elevator, which 
could cause debonding of the elevator skins and, consequently, could 
adversely affect the structural integrity of the elevator.

Actions Since Issuance of Previous Proposal

    Since the issuance of that NPRM, Airbus has issued Revision 1 of 
Service Bulletins A310-55-2016 (for Model A310 series airplanes) and 
A300-55-6014 (for Model A300-600 series airplanes), both dated August 
8, 1995. The original issues of these service bulletins were cited in 
the NPRM as the appropriate sources of service information for 
accomplishment of repetitive thermographic inspections to detect water 
in the elevator, and protection and repair of debonded areas of the 
elevator. Revision 1 of the service bulletins is essentially the same 
as the original issues, however, Revision 1 specifies an increased 
allowable cosmetic repair area and introduces new repair criteria. 
Additionally, Revision 1 provides a threshold and repeat intervals for 
the thermographic inspections based on the specific types of elevators 
that are installed.
    The Direction Generale de l'Aviation Civile (DGAC), which is the 
airworthiness authority for France, classified these service bulletins 
as mandatory and issued French airworthiness directive (CN) 95-206-
189(B), dated October 25, 1995, in order to assure the continued 
airworthiness of these airplanes in France. That French CN supersedes 
the previously-issued French CN 94-184-157(B), dated August 17, 1994. 
The new French CN removes a previous requirement for repetitive Tap 
Test inspections and, instead, it requires thermographic inspections to 
detect water trapped in the elevator. In addition, the new French CN 
indicates that it applies to Model A310 and A300-600 series airplanes 
that are equipped with certain carbon fiber elevators on which Airbus 
Modifications 10489 and 10533 have not been accomplished.
    Additionally, since the issuance of the NPRM, Airbus also has 
issued Service Bulletins A310-55-2019 (for Model A310 series airplanes) 
and A300-55-6016 (for Model A300-600 series airplanes), both Revision 
1, both dated December 18, 1995. These service bulletins describe 
procedures for replacement of existing elevators with new or modified 
elevators. Installation of the new or modified elevators will prevent 
water ingress by adding a second external layer of adhesive and using a 
different type of Tedlar film. Such installation, if accomplished, will 
eliminate the need for the repetitive thermographic inspections.

FAA's Conclusions

    The FAA has examined the findings of the DGAC and has reviewed the 
revised service information. The FAA finds that inspections using 
thermographic techniques are a more reliable method of detecting water 
trapped in the elevators. Therefore, the FAA has determined that the 
NPRM must be revised to remove the requirement for repetitive Tap Test 
inspections and to require, instead, the accomplishment of repetitive 
thermographic inspections in accordance with the latest service 
bulletin revisions.
    Additionally, the FAA finds that the NPRM must be revised to 
specify that the inspection threshold and repetitive inspection 
intervals are based on the specific types of elevators that are 
installed.
    The FAA also finds that the NPRM must be revised to provide for 
replacement of the elevators with new or modified elevators, which, if 
accomplished, would terminate the repetitive thermographic inspections.
    In addition, the applicability of the NPRM has been revised to 
coincide with the applicability of French CN 95-206-189(B).
    Since these changes expand 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.

Type Certification of Affected Airplanes

    These airplane models are manufactured in France and are type 
certificated for operation in the United States under the provisions of 
section 221.29 of the Federal Aviation Regulations (14 CFR 21.29) and 
the applicable bilateral airworthiness agreement. and

Disposition of Comments to the NPRM

    Interested persons were afforded an opportunity to respond to the 
NPRM. Due consideration has been given to pertinent comments that were 
submitted, as described below.

Request to Require Pulse-Echo Ultrasound Inspections

    One commenter requests that the proposed Tap Tests, be replaced 
with pulse-echo ultrasound (A-scan) inspections. The commenter states 
that the pulse-echo ultrasound inspection is much more accurate than a 
Tap Test.
    The FAA concurs partially. The FAA acknowledges that more accurate 
inspections for debonding may exist; however, the FAA does not agree 
that pulse-echo ultrasound inspections are the type of inspections that 
should be required in this case. In developing this AD, the FAA 
considered the fact that pulse-echo ultrasound equipment and procedures 
are not readily available to all operators. Additionally, the FAA 
considered the accuracy of thermographic inspections, as well as the 
accessibility of thermographic inspections to all operators. In 
consideration of these items, the FAA finds that thermographic 
inspections are most appropriate to address the unsafe condition. 
However, under the provisions of paragraph (f) of the final rule, the 
FAA may approve alternative methods of compliance with this AD if data 
are submitted to substantiate that such a method would provide an 
acceptable level of safety.

Request to Update Cost Impact Information

    One commenter requests that the estimated number of affected U.S.-
registered airplanes specified in the cost impact information of the 
proposed rule be revised from 15 to 35, since that is the number of 
Model A300-600 series airplanes in its fleet.
    The FAA concurs and has revised the cost impact information, below, 
to reflect this change.

Cost Impact

    There are approximately 137 Model A310 and A300-600 series 
airplanes of the affected design in the worldwide fleet. The FAA 
estimates that 35 airplanes of U.S. registry would be affected by this 
proposed AD, that it would take approximately 34 work hours per 
airplane to accomplish the proposed actions, and that the average labor 
rate is $60 per work hour. Based on these figures, the cost impact of 
the proposed AD on U.S. operators is estimated to be $71,400, or $2,040 
per airplane, per inspection cycle.
    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.
    Should an operator elect to accomplish the optional replacement of 
the elevators, it would take approximately 14 work hours per airplane 
to accomplish the replacement, at an average labor rate of $60 per work

[[Page 36666]]

hour. The manufacturer would provide the replacement parts at no cost 
to the operator. Based on these figures, the cost impact of the 
optional replacement action is estimated to be $840 per airplane.

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 adding the following new 
airworthiness directive:

Airbus: Docket 94-NM-222-AD.

    Applicability: Model A310 and A300-600 series airplanes equipped 
with carbon fiber elevators having part number (P/N) A5527605500000 
(left-hand side) and P/N A5527605600000 (right-hand side), on which 
Airbus Modifications 10489 and 10533 have not been accomplished; 
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 the presence of water in the elevator, which could 
cause debonding of the elevator skins and, consequently, could 
affect the structural integrity of the elevator, accomplish the 
following:
    (a) Perform a thermographic inspection to detect any water that 
is trapped within the elevator structure, in accordance with either 
Airbus Service Bulletin A310-55-2016, Revision 1, (for Model A310 
series airplanes); or Airbus Service Bulletin A300-55-6014, Revision 
1, (for Model A300-600 series airplanes), both dated August 8, 1995, 
as applicable. Perform the inspection at the time specified in 
paragraph (a)(1) or (a)(2) of this AD, as applicable.
    (1) For airplanes on which CARCOM elevators are installed: 
Perform the inspection at the later of the times specified in 
paragraphs (a)(1)(i) and (a)(1)(ii) of this AD.
    (i) Prior to the accumulation of 4,500 total landings on the 
elevator, or within 5 years after the first landing on the elevator, 
whichever occurs later; or
    (ii) Within 3 months after the effective date of this AD.
    (2) For airplanes on which CASA elevators are installed: Perform 
the inspection at the later of the times specified in paragraphs 
(a)(2)(i) and (a)(2)(ii) of this AD.
    (i) Prior to the accumulation of 5,000 total landings on the 
elevator, or within 6 years after the first landing on the elevator, 
whichever occurs later.
    (ii) Within 3 months after the effective date of this AD.
    (b) If no water is detected, repeat the thermographic inspection 
required by paragraph (a) of this AD thereafter at the time 
specified in paragraph (b)(1) or (b)(2) of this AD, as applicable.
    (1) For airplanes on which CARCOM elevators are installed: 
Repeat the inspection at intervals not to exceed 4,500 landings or 5 
years, whichever occurs first;
    (2) For airplanes on which CASA elevators are installed: Repeat 
the inspection at intervals not to exceed 5,000 landings or 6 years, 
whichever occurs first.
    (c) If any water is detected in the elevator, and the area is 
within the limits specified in the Accomplishment Instructions of 
either Airbus Service Bulletin A310-55-2016, Revision 1, (for Model 
A310 series airplanes), or A300-55-6016 (for Model A300-600 series 
airplanes), both Revision 1, both dated August 8, 1995, as 
applicable: Prior to further flight, protect and/or repair the 
elevator in accordance with the applicable service bulletin. 
Thereafter, repeat the thermographic inspections required by 
paragraph (b) of this AD at the times specified in the 
Accomplishment Instructions of the applicable service bulletin until 
the replacement of the elevator is accomplished as specified in 
paragraph (e) of this AD.
    (d) If any water is detected in the elevator that exceeds the 
limits specified by Airbus Service Bulletin A310-55-2016 (for Model 
A310 series airplanes), or Airbus Service Bulletin A300-55-6014 (for 
Model A300-600 series airplanes), both Revision 1, and both dated 
August 8, 1995, as applicable: Accomplish the requirements of either 
(d)(1) or (d)(2) of this AD, as applicable.
    (1) If any damage is detected that is less than or equal to 
60,000 square millimeters or 93 square inches, prior to further 
flight, protect or repair and perform repetitive inspections in 
accordance with the applicable service bulletin.
    (2) If any damage is detected that is more than 60,001 square 
millimeters or 93 square inches, prior to further flight, perform 
the requirements of either paragraph (d)(2)(i) or (d)(2)(ii) of this 
AD.
    (i) If the damage is within the limits of the Structural Repair 
Manual (SRM) (Ref. SRM 55-20-00), accomplish the repair in 
accordance with the SRM; or
    (ii) Replace the elevator in accordance with Airbus Service 
Bulletin A310-55-2019 (for Model A310 series airplanes), or A300-55-
6016 (for Model A300-600 series airplanes), both dated December 18, 
1995. No further action is required by this AD.
    (e) Replacement of the elevator in accordance with either Airbus 
Service Bulletin A310-55-2019 (for Model A310 series airplanes), or 
A300-55-6016 (for Model A300-600 series airplanes), both dated 
December 18, 1995, as applicable, constitutes terminating action for 
the requirements 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, 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 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Standardization Branch, ANM-113.

    (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.


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    Issued in Renton, Washington, on July 8, 1996.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service. -
[FR Doc. 96-17741 Filed 7-11-96; 8:45 am]
BILLING CODE 4910-13-U