[Federal Register Volume 61, Number 84 (Tuesday, April 30, 1996)]
[Proposed Rules]
[Pages 18995-18997]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-10625]



 ========================================================================
 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.
 
 ========================================================================
 

  Federal Register / Vol. 61, No. 84 / Tuesday, April 30, 1996 / 
Proposed Rules  

[[Page 18995]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 95-NM-263-AD]
RIN 2120-AA64


Airworthiness Directives; Airbus Model A300 B2 and B4 Series 
Airplanes, Excluding Model 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 certain Airbus Model A300 
B2 and B4 series airplanes, that currently requires repetitive visual 
inspections to detect cracks in the forward intermediate section skin 
at frame 30A where it joins stringer 30, and repair, if necessary. This 
action would add eddy current inspection(s) to detect cracks of the 
outer skin of the fuselage, which would terminate the repetitive 
detailed visual inspections. This action also would require repair of 
any cracked area and modification of the structure at certain frames. 
This proposal is prompted by in-service experience which has identified 
fatigue cracks in this area. The actions specified by the proposed AD 
are intended to prevent fatigue cracking, which could result in rapid 
decompression of the airplane.

DATES: Comments must be received by June 10, 1996.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 95-NM-263-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: Tim Backman, Aerospace Engineer, 
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206) 
227-2797; fax (206) 227-1149.

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 95-NM-263-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. 95-NM-263-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    On May 15, 1990, the FAA issued AD 90-11-09, amendment 39-6611 (55 
FR 21185, May 23, 1990), applicable to certain Airbus Model A300 B2 and 
B4 series airplanes, to require repetitive visual inspections to detect 
cracks in the forward intermediate section skin at frame 30A where it 
joins stringer 30, and repair, if necessary. That action was prompted 
by in-service experience which identified fatigue cracks in this area. 
The requirements of that AD are intended to prevent rapid decompression 
of the airplane, as a result of the problems associated with fatigue 
cracking.
    In the preamble to that AD, the FAA indicated that the actions 
required by that AD were considered ``interim action'' and that further 
rulemaking action was being considered. The FAA now has determined that 
further rulemaking action is indeed necessary, and this proposed AD 
follows from that determination.

Explanation of New Service Information

    Since the issuance of AD 90-11-09, Airbus has issued Service 
Bulletin A300-53-283, Revision 2, dated March 17, 1994. The service 
bulletin describes procedures for eddy current inspection(s) to detect 
cracks of the outer skin of the fuselage at frames 28A and 30A above 
stringer 30, which would eliminate the need for the repetitive detailed 
visual inspections. The service bulletin also describes procedures for 
repairing the cracked area with a filler and doubler installation. In 
addition, the service bulletin permits further flight, under certain 
conditions, with outer skin that is cracked within certain limits.
    Airbus has also issued Service Bulletin A300-53-285, Revision 1, 
dated November 22, 1993, which describes procedures for modification of 
the structure at frames 28A and 30A between stringers 27 and 30 (left- 
and right-hand). The modification involves cutting the frames and 
installing strips, fillers, couplings, sections, sheets, and angles at 
the subject area. Accomplishment of the modification will eliminate 
possible cracking in the outer skin of the fuselage at frames 28A and 
30A, and would positively address the unsafe condition identified as 
rapid

[[Page 18996]]

decompression of the airplane due to fatigue cracking.
    The DGAC has approved these service bulletin and issued French 
airworthiness directive 90-093-110(B)R1, dated September 30, 1990, in 
order to assure the continued airworthiness of these airplanes in 
France.

FAA's Conclusions

    This airplane model is manufactured in France and is 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 90-11-09 to 
continue to require repetitive detailed visual inspections to detect 
cracks of the forward intermediate section skin of the fuselage at the 
junction of frame 30A and stringer 30.
    However, this proposal would add a requirement to accomplish eddy 
current inspections to detect cracks of the outer skin of the fuselage 
at frames 28A and 30A above stringer 30. This inspection action would 
constitute terminating action for the repetitive detailed visual 
inspections.
    The proposed AD also would require repair of any cracked area, and 
modification of the structure at frames 28A and 30A between stringer 27 
and 30 (left- and right-hand).
    The actions would be required to be accomplished in accordance with 
the service bulletins described previously.

Differences Between Service Information and Proposed Rule

    Operators should note that, unlike the procedures described in 
Airbus Service Bulletin A300-53-283, this proposed AD would not permit 
further flight with cracking detected in the outer skin within certain 
limits under certain conditions. The FAA has determined that, due to 
the safety implications and consequences associated with such cracking, 
the subject outer skin that is found to be cracked must be repaired.
    Operators should also note that the proposed AD would differ from 
Airbus Service Bulletin A300-53-283 in that it would require the 
initial eddy current inspection to be accomplished prior to the 
accumulation of 14,100 total landings or 22,000 flight hours after the 
effective date of this AD, whichever occurs first. (The service 
bulletin recommends that the limited inspection be conducted prior to 
the accumulation of 18,000 flight or 24,000 flight hours, whichever 
occurs first.) In developing an appropriate compliance time for this 
action, the FAA considered not only the degree of urgency associated 
with addressing the subject unsafe condition, but the susceptibility of 
the outer skin of the fuselage to fatigue cracking, which could result 
in rapid decompression of the airplane. The FAA has also received 
reports of fatigue cracking on affected airplanes that had accumulated 
as few as 14,100 total flight cycles. In consideration of these items, 
the FAA finds that the initial eddy current inspection conducted at the 
proposed compliance time stated previously will better ensure that any 
detrimental effect associated with fatigue cracking will be identified 
and corrected prior to the time that it could adversely affect the 
outer skin of the fuselage.
    Furthermore, the FAA has determined that long term continued 
operational safety will be better assured by design changes to remove 
the source of the problem, rather than by repetitive inspections. Long 
term inspections may not be providing the degree of safety assurance 
necessary for the transport airplane fleet. This, coupled with a better 
understanding of the human factors associated with numerous continual 
inspections has led the FAA to consider placing less emphasis on 
inspections and more emphasis on design improvements. The proposed 
modification requirement is in consonance with these conditions.

Cost Impact

    There are approximately 24 Airbus Model A300 B2 and B4 series 
airplanes, excluding Model A300-600 series airplanes, of U.S. registry 
would be affected by this proposed AD.
    The detailed visual inspections that are currently required by AD 
90-11-09 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 of the detailed visual inspections 
currently required is estimated to be $1,440, or $60 per airplane, per 
inspection cycle.
    The eddy current inspection that is proposed in this new AD action 
would 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 of the proposed eddy current inspection 
requirements of this AD is estimated to be $1,440, or $60 per airplane, 
per inspection cycle.
    The modification that is proposed in this new AD action would take 
approximately 270 work hours per airplane to accomplish, at an average 
labor rate of $60 per work hour. Required parts would cost 
approximately $7,200 per airplane. Based on these figures, the cost 
impact on U.S. operators of the proposed modification requirements of 
this AD is estimated to be $561,600, or $23,400 per airplane.
    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.

[[Page 18997]]

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 USC 106(g), 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by removing amendment 39-6611 (55 FR 
21185, May 23, 1990), and by adding a new airworthiness directive (AD), 
to read as follows:

Airbus Industrie: Docket 95-NM-263-AD. Supersedes AD 90-11-09, 
Amendment 39-6611.

    Applicability: Model A300 B2 and B4 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 otherwise 
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.

    Note 2: Airbus Model A300-600 series airplane are not subject to 
this AD.

    To prevent fatigue cracking, which could result in rapid 
decompression of the airplane, accomplish the following:
    (a) For airplanes on which Airbus All Operators Telex (AOT) 53/
90/01, dated April 12, 1990 has been accomplished: Prior to the 
accumulation of 18,000 total landings or 24,000 total hours time-in-
service, whichever occurs first, or within 100 landings after June 
11, 1990 (the effective date of AD 90-11-09, amendment 39-6611), 
whichever occurs later, perform a detailed visual inspection to 
detect cracks of the forward intermediate section skin of the 
fuselage at the junction of frame 30A and stringer 30, in accordance 
with Airbus All Operators Telex 53/90/01, dated April 12, 1990.
    (1) If no cracks are detected, repeat the detailed visual 
inspection thereafter at intervals not to exceed 2,000 landings 
until the requirements of paragraph (b) of this AD are accomplished.
    (2) If any crack is detected, prior to further flight, repair it 
in accordance with the AOT. After any crack is repaired, prior to 
the accumulation of 15,000 total landings or 20,000 total hours 
time-in-service, whichever occurs first, repeat the detailed visual 
inspection until the requirements of paragraph (b) of this AD are 
accomplished.
    (b) For all airplanes: Perform an eddy current inspection to 
detect cracks of the outer skin of the fuselage at frames 28A and 
30A above stringer 30, in accordance with Airbus Service Bulletin 
A300-53-283, Revision 2, dated March 17, 1994, at the time specified 
in either paragraph (b)(1) or (b)(2) of this AD, as applicable. 
Accomplishment of the eddy current inspection terminates the 
repetitive visual inspection requirements of paragraph (a) of this 
AD.
    (1) For airplanes on which the requirements of paragraph (a) of 
this AD have been initiated: Perform the eddy current inspection 
prior to the accumulation of 2,000 landings since the last 
inspection performed in accordance with paragraph (a) of this AD, or 
within 100 landings after the effective date of this AD, whichever 
occurs later.
    (2) For airplanes other than those identified in paragraph 
(b)(1) of this AD: Perform the eddy current inspection at the later 
of the times specified in paragraph (b)(2)(i) or (b)(2)(ii):
    (i) Prior to the accumulation of 14,100 total landings or 22,000 
total flight hours after the effective date of this AD, whichever 
occurs first; or
    (ii) Within 100 landings after the effective date of this AD.
    (c) If no crack is detected during the eddy current inspection 
required by paragraph (b) of this AD, repeat the eddy current 
inspection thereafter at intervals not to exceed 3,000 landings.
    (d) If any crack is detected during any eddy current inspection 
required by this AD, prior to further flight, repair it in 
accordance with Airbus All Operators Telex 53/90/01, dated April 12, 
1990, or Airbus Service Bulletin A300-53-283, Revision 2, dated 
March 17, 1994. After accomplishing the repair, within 15,000 
landings or 20,000 flight hours after repair, whichever occurs 
first, modify the structure at frames 28A and 30A between stringers 
27 and 30 (left- and right-hand), in accordance with Airbus Service 
Bulletin A300-53-285, Revision 1, dated November 22, 1993. 
Accomplishment of this reinforcement constitutes terminating action 
for this AD.
    (e) Except for airplanes on which the repair required by 
paragraph (d) of this AD has been accomplished: Modify the structure 
at frames 28A and 30A between stringers 27 and 30 (left- and right-
hand), in accordance with Airbus Service Bulletin A300-53-285, 
Revision 1, dated November 22, 1993, at the later of the times 
specified in paragraphs (e)(1) or (e)(2) of this AD. Accomplishment 
of this modification constitutes terminating action for the eddy 
current inspection requirements of paragraph (c) of this AD.
    (1) Prior to the accumulation of 25,000 total landings or 40,000 
total flight hours, whichever occurs first.
    (2) Within 1,000 landings after the effective date 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 3: 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.

    Issued in Renton, Washington, on April 24, 1996.
S.R. Miller,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 96-10625 Filed 4-29-96; 8:45 am]
BILLING CODE 4910-13-U