Events Leading to the Issuance of This AD
A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an AD that would apply to aircraft that have a certain SAFT America Inc. P/N 021929-000 (McDonnell Douglas P/N 43BO34LB02) or P/N 021904-000 (McDonnell Douglas P/N 43BO34LB03) nickel cadmium battery installed was published in the Federal Register as a notice of proposed rulemaking (NPRM) on March 2, 1998 (63 FR 10156). The NPRM proposed to require replacing all battery terminal screws, verifying that the battery contains design specification cells, and replacing the cells if the battery contains non-design specification cells. Accomplishment of the proposed action as specified in the NPRM would be in accordance with SAFT Aviation Batteries Service Bulletin Document No. A00027, Rev F, dated January 15, 1998.
The NPRM was the result of an incident where the cell screws on one of the affected batteries were exposed tochloride, which caused the heads of some fasteners to shear off and eventually resulted in the battery exploding.
Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the comments received.
Comment Issue No. 1: Exclude Those Batteries Maintained by Airlines
One commenter suggests that the AD be developed to identify those batteries that have undergone repairs by third party vendors or batteries that were purchased in conditions other than new. Two commenters state that the AD should not apply to batteries maintained by airlines with internal battery shops where the repair process is contained within an FAA-approved maintenance program.
The FAA does not concur. The FAA does not have any information that would show that the way airlines repair batteries is significantly different from third party (repair station) processes. While the FAA realizes that some airlines will not have any problems with the batteries on their fleet of aircraft, this number would probably be very closely related to the number of repair stations that maintain batteries in a very similar manner. The FAA knows of no other way of assuring that all of the affected batteries have acceptable battery screws and design specification cells than to require the actions specified in the NPRM.
In addition, FAA site visits to several maintenance facilities to review battery maintenance programs revealed that some airlines were installing incorrect screws, were not using the latest battery maintenance manual, and were modifying batteries without having the proper documentation. The FAA will evaluate an airline's maintenance practices on a case-by-case basis provided that an Aviation Safety Inspector that is familiar with the maintenance program submits an alternative method of compliance (AMOC) in accordance with the procedures in paragraph (d) of this AD. The FAA will evaluate the submittal and will either approve or deny the AMOC accordingly.
No changes to the final rule have been made as a result of these comments.
Comment Issue No. 2: Develop a Method of Tracing Those Batteries in Compliance with the AD
One commenter suggests a part number change be implemented in order to trace those batteries that are in compliance with the AD. The part number change will assure that the affected aircraft are not demodified by non-routine battery replacement and would assist in tracking the compliance of the AD.
The FAA does not concur that a part number change is necessary. The manufacturer assigns a part number that is intended to be used for the life of the battery. This part number establishes traceability and service history of the battery. When the AD is complied with, the repair facility or maintenance shop will record and document compliance with the AD as specified in the Federal Aviation Regulations (14 CFR). By regulation, an aircraft cannot be legally operated if not in compliance with an AD; demodifying the battery would put the aircraft in non-compliance with the AD. However, Saft America Inc. has agreed to supply a plastic label for the battery that will indicate compliance with the AD. This label shall not cover the original part number of the battery. The FAA will include information in the AD to communicate the availability of the plastic label.
Comment Issue No. 3: Revise the Service Bulletin to Include Certain Items
One commenter requests that, in order to avoid any confusion, Saft America Inc. should reference the component maintenance manual in the Service Bulletin.
One commenter states that the terminal screw CMM IPL figure and item number is additional information that the airlines will use to perform the required AD. The commenter requests that it be included in the service bulletin.
One commenter requests that Saft include a list of authorized sources for obtaining terminal screws, as this would assist the repair shop in obtaining the necessary parts.
Saft America Inc. has revised Saft Aviation Batteries Service Bulletin Document No. A00027 to the Revision G level (dated July 14, 1998) to incorporate reference to the component maintenance manual, to include a list of suppliers that will assist the repair shops in obtaining the parts (from an authorized dealer) that are necessary to comply with the AD, and include the terminal screw CMM IPL figure and item number. This service bulletin will be incorporated into the AD.
Comment Issue No. 4: Change the Compliance Time/Parts Availability
One commenter requests that the effective date be changed to coincide with parts availability.
The FAA has been assured by Saft America Inc. that parts will be available for all aircraft by the compliance time of "at the next scheduled battery maintenance that occurs 3 calendar months after the effective date of this AD or within the next 15 calendar months after the effective dateof this AD, whichever occurs first."
No change to the final rule has been made as a result of this comment.
Comment Issue No. 5: Change the Terminal Screw Part Number
One commenter recommends that the terminal screw part be changed to differentiate the suspect terminal screws from the new terminal screws.
The FAA does not concur. The part number does not appear on the terminal screw due to the small size of the screw. The part number appears on the package that the new screw comes in. However, to differentiate between the screws, the new terminal screws have markings on the head of the screws (either two adjacent protrusions or two protrusions 180 degrees apart), while the suspect screws have no markings.
No changes to the final rule are necessary as a result of this comment.
The FAA's Determination
After careful review of all available information related to the subject presented above, the FAA has determined that air safety and the public interest require the adoption of the rule as proposed except for the addition of information communicating the availability of the compliance label from Saft, the incorporation of the revised service bulletin, and minor editorial corrections. The FAA has determined that this addition of the compliance label information, the incorporation of the revised service bulletin, and the minor corrections will not change the meaning of the AD and will not add any additional burden upon the public than was already proposed.
Cost Impact
The FAA estimates that 1,004 aircraft in the U.S. registry could have at least one of the affected batteries installed and will be affected by this AD, that it will take approximately 16 workhours per aircraft to accomplish these actions, and that the average labor rate is approximately $60 an hour. Parts cost approximately $78 per battery (two batteries per aircraft = $156). Based on these figures, the total cost impact of this AD on U.S. operators is estimated tobe $1,120,464, or $1,116 per aircraft if all aircraft have two affected batteries installed. Compliance Time of This AD
The unsafe condition specified by this AD is caused by corrosion. Corrosion can occur regardless of whether the aircraft is in operation. Therefore, to assure that the unsafe condition specified in this AD does not go undetected for a long period of time, the compliance is presented in calendar time instead of hours time-in-service (TIS).
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.
For the reasons discussed above, I certify that this action (1) is not a "significant regulatory action" under Executive Order 12866; (2) is not a "significant rule" under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) 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 final 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, 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.
39.13 [Amended]
2. Section 39.13 is amended by adding a new airworthiness directive (AD) to read as follows: