AD Amdt-39-11450

[Federal Register Volume 64, Number 235 (Wednesday, December 8, 1999)]
[Rules and Regulations]
[Pages 68620-68623]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 99-31474]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-341-AD; Amendment 39-11450; AD 99-25-07]
RIN 2120-AA64


Airworthiness Directives; BFGoodrich Main Brake Assemblies as 
Installed on Airbus Model A319 and A320 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
is applicable to certain BFGoodrich main brake assemblies as installed 
on Airbus Model A319 and A320 series airplanes. This action requires a 
one-time inspection of the wear indicator pins to determine the level 
of wear of the main brake assemblies of the main landing gear (MLG), 
and corrective actions, if necessary. This action also requires 
modification of the main brake assemblies of the MLG, and incorporation 
of specified wear limits into the maintenance inspection program. This 
amendment is prompted by in-service reports of brake deterioration 
caused by thermal

[[Page 68621]]

oxidation of the carbon disks of certain BFGoodrich main brake 
assemblies. The actions specified in this AD are intended to prevent 
thermal oxidation of the main brake assemblies, which could result in 
deterioration of the MLG brakes, and consequent reduced braking 
performance.

DATES: Effective December 23, 1999.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of December 23, 1999.
    Comments for inclusion in the Rules Docket must be received on or 
before January 7, 2000.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 99-NM-341-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056.
    The service information referenced in this AD may be obtained from 
BFGoodrich Aircraft Wheels and Brakes, P.O. Box 340, Troy, Ohio, 45373. 
This information may be examined at the FAA, Transport Airplane 
Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the 
Office of the Federal Register, 800 North Capitol Street, NW., suite 
700, Washington, DC.

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: The FAA has received in-service reports of 
brake deterioration of certain BFGoodrich main brake assemblies 
installed on Airbus Model A319 and A320 series airplanes. Investigation 
revealed that the deterioration of these BFGoodrich brakes was caused 
by thermal oxidation of the carbon material due to exposure to elevated 
temperatures for prolonged periods of time. Further investigation 
revealed that the oxidation inhibitor process used by BFGoodrich does 
not completely prevent oxidation of the carbon brake material. 
BFGoodrich advises that these carbon brakes, which are susceptible to 
this oxidation condition, are only used on Airbus Model A319 and A320 
series airplanes. This condition, if not corrected, could result in 
deterioration of the MLG brakes, and consequent reduced braking 
performance.

Explanation of Relevant Service Information

    BFGoodrich has issued Service Bulletins 2-1598-32-1, and 2-1600-32-
2, both dated November 5, 1999, which describe procedures for removal 
of main brake assemblies with wear indicator pins having a length of 
0.20 inch or less, and modification of the main brake assemblies of the 
MLG. The modification involves reducing the length of the wear 
indicator pins, and re-identifying the piston housings and 
identification plates of the main brake assemblies.

FAA's Determination

    The FAA has determined that a direct correlation exists between the 
amount of wear and the degree of thermal oxidation. Therefore, by 
limiting the wear of the carbon brake assemblies, as required by this 
AD, thermal oxidation is controlled to an acceptable level.

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.

Explanation of Requirements of 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, this AD is being issued to prevent thermal 
oxidation of the main brake assemblies, which could result in 
deterioration of the MLG brakes, and consequent reduced braking 
performance. This AD requires one-time detailed visual inspection of 
the wear indicator pins to determine the level of wear of the main 
brake assemblies of the main landing gear (MLG), and corrective 
actions, if necessary. This AD also requires modification of the main 
brake assemblies of the MLG, and incorporation of specified wear limits 
into the FAA-approved maintenance inspection program. Certain actions 
are required to be accomplished in accordance with the service 
bulletins described previously, except as discussed below.

Interim Action

    This is considered to be interim action. The brake manufacturer has 
advised that it currently is developing a modification that will 
positively address the unsafe condition addressed by this AD. Once this 
modification is developed, approved, and available, the FAA may 
consider additional rulemaking.

Differences Between AD and Service Information

    Operators should note that the BFGoodrich service bulletins allow 
an option of either replacement of any main brake assembly with 0.20 
inch or less remaining on the wear indicator pins, or modification of 
the brake assembly by reducing the wear indicator pins. Additionally, 
the BFGoodrich service bulletins do not recommend a compliance time for 
either action. However, this AD requires a one-time inspection of the 
wear indicator pins within 10 days, and replacement of the brake 
assembly if the remaining length of the wear indicator pin is equal to 
or less than 0.20 inch. This AD also requires modification of the brake 
assembly to reduce the length of the wear indicator pins within 30 
days, and re-identification of the piston housings and identification 
plates no later than the next brake removal. The FAA finds that in view 
of in-service reports of main brake assembly deterioration, the 
requirements specified in this AD are appropriate to maintain a 
consistent main brake assembly configuration for all airplanes that are 
affected by the subject unsafe condition.

Determination of Rule's Effective Date

    Since a situation exists that requires the immediate adoption of 
this regulation, it is found that notice and opportunity for prior 
public comment hereon are impracticable, and that good cause exists for 
making this amendment effective in less than 30 days.

Comments Invited

    Although this action is in the form of a final rule that involves 
requirements affecting flight safety and, thus, was not preceded by 
notice and an opportunity for public comment, comments are invited on 
this rule. Interested persons are invited to comment on this 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 under the caption ADDRESSES. All 
communications received on or before the closing date for comments will 
be considered, and this rule may be amended in light of the comments 
received. Factual information that supports the commenter's ideas and 
suggestions is extremely helpful in evaluating the effectiveness of the 
AD action and determining whether additional rulemaking action would be 
needed.

[[Page 68622]]

    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the rule that might 
suggest a need to modify the 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 that 
summarizes each FAA-public contact concerned with the substance of this 
AD will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this rule must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 99-NM-341-AD.'' The postcard will be date stamped and 
returned to the commenter.

Regulatory Impact

    The regulations adopted herein will 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 final 
rule does not have sufficient federalism implications to warrant the 
preparation of a Federalism Assessment.
    The FAA has determined that this regulation is an emergency 
regulation that must be issued immediately to correct an unsafe 
condition in aircraft, and that it is not a ``significant regulatory 
action'' under Executive Order 12866. It has been determined further 
that this action involves an emergency regulation under DOT Regulatory 
Policies and Procedures (44 FR 11034, February 26, 1979). If it is 
determined that this emergency regulation otherwise would be 
significant under DOT Regulatory Policies and Procedures, a final 
regulatory evaluation will be prepared and placed in the Rules Docket. 
A copy of it, if filed, may be obtained from the Rules Docket at the 
location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends 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:

99-25-07  BFGoodrich: Amendment 39-11450. Docket 99-NM-341-AD.

    Applicability: BFGoodrich main brake assemblies having part 
number (P/N) 2-1598 or 2-1600, as installed on Airbus Model A319 and 
A320 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 (d) 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 thermal oxidation of the main brake assemblies of the 
main landing gear (MLG), which could result in deterioration of the 
MLG brakes, and consequent reduced braking performance, accomplish 
the following:

Detailed Visual Inspection

    (a) Within 10 days after the effective date of this AD, perform 
a one-time detailed visual inspection of the wear indicator pins to 
determine the level of wear of the main brake assemblies of the MLG, 
as specified in BFGoodrich Service Bulletin 2-1598-32-1, or 2-1600-
32-2, both dated November 5, 1999, as applicable.

    Note 2: For the purposes of this AD, a detailed visual 
inspection is defined as: ``An intensive visual examination of a 
specific structural area, system, installation, or assembly to 
detect damage, failure, or irregularity. Available lighting is 
normally supplemented with a direct source of good lighting at 
intensity deemed appropriate by the inspector. Inspection aids such 
as mirror, magnifying lenses, etc. may be used. Surface cleaning and 
elaborate access procedures may be required.''

    (1) If the remaining length of any wear indicator pin is less 
than or equal to 0.20 inch (5.1 mm) with the brake pressurized, 
prior to further flight, replace the brake assembly with a new or 
serviceable brake assembly, in accordance with Chapter 32-42-27 of 
the applicable Airplane Maintenance Manual (AMM).
    (2) If the remaining length of all wear indicator pins is 
greater than 0.20 inch (5.1 mm) with the brake pressurized, no 
further action is required by this paragraph.

Modification

    (b) Within 30 days after the effective date of this AD, modify 
the main brake assemblies of the MLG by reducing the length of the 
wear indicator pins, in accordance with BFGoodrich Service Bulletin 
2-1598-32-1, or 2-1600-32-2, both dated November 5, 1999, as 
applicable; and incorporate the new wear limits for the main brake 
assemblies specified in the applicable service bulletin into the 
FAA-approved maintenance program and comply with those limits 
thereafter. After accomplishing the modification, but no later than 
the next brake removal, re-identify the brake assemblies in 
accordance with the applicable service bulletin.

    Note 3: Once an operator has complied with the requirements of 
paragraph (b) of this AD, that paragraph does not require that 
operators subsequently record accomplishment of the requirements 
each time a brake is inspected or overhauled in accordance with that 
operator's FAA-approved maintenance inspection program.

Spares

    (c) As of the effective date of this AD, no person shall install 
on any airplane a BFGoodrich main brake assembly having P/N 2-1598 
or 2-1600, unless that assembly has been modified in accordance with 
this AD.

Alternative Methods of Compliance

    (d) 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 4: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the International Branch, ANM-116.

Special Flight Permits

    (e) 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.

Incorporation by Reference

    (f) The actions shall be done in accordance with BFGoodrich 
Service Bulletin 2-1598-32-1, dated November 5, 1999, or BFGoodrich 
Service Bulletin 2-1600-32-2, dated November 5, 1999, as applicable. 
This incorporation by reference was approved by the Director of the 
Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 
51. Copies may be obtained from BFGoodrich Aircraft Wheels and 
Brakes, P.O. Box 340, Troy, Ohio, 45373. Copies may be

[[Page 68623]]

inspected at the FAA, Transport Airplane Directorate, 1601 Lind 
Avenue, SW., Renton, Washington; or at the Office of the Federal 
Register, 800 North Capitol Street, NW., suite 700, Washington, DC.
    (g) This amendment becomes effective on December 23, 1999.

    Issued in Renton, Washington, on November 24, 1999.
D.L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 99-31474 Filed 12-7-99; 8:45 am]
BILLING CODE 4910-13-U