Airworthiness Directives; Saab Model SAAB 340B and SAAB 2000 Series Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes the supersedure of an existing airworthiness directive (AD), applicable to certain Saab Model SAAB 340B and SAAB 2000 series airplanes, that currently requires an inspection of the fluorescent lamps in the cabin area to ensure correct installation, and correction, if necessary; and an inspection of the lampholders to identify any discrepancies and to ensure the security of the back covers, and replacement of discrepant lampholders with new lampholders; installation of retaining clips on certain Page Aerospace lampholders; and reinspection of the lamps to ensure correct installation after replacement or reinstallation of the lamps or lampholders, and corrections, if necessary. This action would add a requirement for replacement of the electronic light ballasts with improved ballasts, which would terminate the reinspections. This action would also expand the applicability of the existing AD. 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 electrical arcing between the fluorescent tube pins and the lampholders, which could burn the surrounding area and lead to smoke and fumes in the passenger compartment or lavatory area.

DATES:

Comments must be received by April 26, 2000.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 99-NM-354-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 SAAB Aircraft AB, SAAB Aircraft Product Support, S-581.88, Linköping, Sweden. 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 99-NM-354-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. 99-NM-354-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

On June 13, 1997, the FAA issued AD 97-13-06, amendment 39-10052 (62 FR 33545, June 20, 1997), applicable to certain Saab Model SAAB 340B and SAAB 2000 series airplanes, to require an inspection of the fluorescent lamps in the cabin area to ensure correct installation, and corrections, if necessary. That AD also requires an inspection of the lampholders to identify any discrepancies and to ensure the security of the back covers, and replacement of discrepant lampholders with new lampholders; installation of retaining clips on certain Page Aerospace lampholders; and reinspection of the lamps to ensure correct installation after replacement or reinstallation of the lamps or lampholders, and corrections, if necessary. That action was prompted by reports indicating that loose back covers on the lampholders and incorrect lamp installations have led to electrical arcing between fluorescent tube pins and lampholders and consequent charring or melting of the affected areas. The requirements of that AD are intended to prevent such electrical arcing, which could burn the surrounding area and lead to smoke and fumes in the passenger compartment or lavatory area.

Actions Since Issuance of Previous Rule

Since the issuance of that AD, the Luftfartsverket (LFV), which is the airworthiness authority for Sweden, has advised the FAA that additional Model SAAB 340B and SAAB 2000 series airplanes may be subject to fluorescent lampholder charring due to the incorrect installation of fluorescent lamps in their holders. Additionally, the LFV has advised the FAA that a modification is now available that will eliminate the need for reinspecting the fluorescent lamps following each replacement or reinstallation of the lamps or lampholders.

In the preamble to AD 97-13-06, 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 Relevant Service Information

Saab has issued Service Bulletins 340-33-048, Revision 01, dated January 21, 1999 (for Model SAAB 340B series airplanes), and 2000-33-015 (for Model SAAB 2000 series airplanes), dated January 29, 1999. These service bulletins describe procedures for replacement of the electronic light ballasts with improved ballasts, which would eliminate the need for reinspection of the fluorescent lampholders. Additionally, Service Bulletin 340-33-048, Revision 01, references Service Bulletin 340-33-049, dated January 21, 1999, which describes procedures for concurrent modification of the ballasts to ensure sufficient clearance between the ballast and certain transistors.

Saab also has issued Service Bulletin 340-33-047, Revision 01, dated June 26, 1998. The procedures in Revision 01 are identical to those in the original issue of the service bulletin, which is cited as the appropriate source of service information in AD 97-13-06 for Model SAAB 340B series airplanes. However, Revision 01 specifies additional airplanes in the effectivity of the service bulletin, and adds a reference to Saab Service Bulletin 340-33-048 (Saab Modification No. 2936), which would eliminate the need for reinspections of the lamps.

The LFV classified Service Bulletin 340-33-047, Revision 01, as mandatory, and approved Service Bulletins 340-33-048, Revision 01; 340-33-049; and 2000-33-015; and issued Swedish airworthiness directives 1-113R1 and 1-114R1, both dated September 8, 1998, in order to assure the continued airworthiness of these airplanes in Sweden.

FAA's Conclusions

These airplane models are manufactured in Sweden 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 LFV has kept the FAA informed of the situation described above. The FAA has examined the findings of the LFV, 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 97-13-06 to continue to require the actions specified in that AD, and to add a requirement for replacement of the electronic light ballasts with improved ballasts, which would terminate the requirement for reinspections of the lamps. The proposed AD would also expand the applicability of the existing AD to include additional Model SAAB 340B and SAAB 2000 series airplanes that are also subject to the identified unsafe condition. The actions would be required to be accomplished in accordance with the service bulletins described previously, except as discussed below.

Differences Between Proposed Rule and Service Bulletin

Operators should note that this AD proposes to mandate, within 18 months, the replacement of the light ballasts with improved ballasts as terminating action for the reinspections. (Incorporation of the terminating action specified in this service bulletin is optional in Swedish airworthiness directives 1-113R1 and 1-114R1.)

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 replacement requirement is consistent with these conditions.

Cost Impact

There are approximately 78 airplanes of U.S. registry that would be affected by this proposed AD.

The actions that are currently required by AD 97-13-06 take approximately 7 work hours 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 actions on U.S. operators is estimated to be $420 per airplane.

The new actions that are proposed in this AD action would take as much as 9 work hours per airplane to accomplish, at an average labor rate of $60 per work hour. Required parts would be provided free of charge by the manufacturer. Based on these figures, the cost impact of the proposed requirements of this AD on U.S. operators is estimated to be $42,120, or $540 per airplane.

The cost impact figures discussed above are 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.

Regulatory Impact

The regulations proposed herein would not have a substantial direct effect 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, it is determined that this proposal would not have federalism implications under Executive Order 13132.

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.