00-17300. Airworthiness Directives; Saab Model SAAB SF340A and SAAB 340B Series Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Final rule.

SUMMARY:

This amendment adopts a new airworthiness directive (AD), applicable to certain Saab Model SAAB SF340A and SAAB 340B series airplanes, that requires replacing the smoke detectors in the cargo compartment with new, improved smoke detectors. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to prevent false smoke warnings from the cargo compartment smoke detectors, which could result in aborted takeoffs, diversions of flight routes, and emergency evacuation of flight crew and passengers.

DATES:

Effective August 17, 2000.

The incorporation by reference of certain publications listed in the regulations is approved by the Director of the Federal Register as of August 17, 2000.

ADDRESSES:

The service information referenced in this AD may be obtained from Saab Aircraft AB, SAAB Aircraft Product Support, S-581.88, Linköping, Sweden. This information may be examined at the Federal Aviation Administration (FAA), Transport Airplane Directorate, Rules Docket, 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 [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an airworthiness directive (AD) that is applicable to certain Saab Model SAAB SF340A and SAAB 340B series airplanes was published in the Federal Register on March 27, 2000 (65 FR 16158). That action proposed to require replacing the smoke detectors in the cargo compartment with new, improved smoke detectors.

Comment Received

Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the single comment received.

Request for Delay in AD Issuance

One commenter, the vendor for the existing (Fenwall) smoke detector, states that the proposed AD was not warranted, and requests that issuance of the final rule be delayed a minimum of 90 days. The commenter disagrees with the proposed requirement to replace the existing smoke detectors with another vendor's (Cerberus) smoke detector. As background, the commenter notes that the existing Fenwall smoke detector was susceptible to false alarms due to high humidity conditions; and, in response, Fenwall Safety Systems initiated a product improvement via Service Bulletin #9701 to correct the problem. The commenter states that about 1,000 #9701 kits have been installed to date, and a recent polling of operators indicates that the humidity problem is no longer a significant concern; i.e., the existing smoke detector performs adequately after this modification. The commenter requests the 90-day delay to resolve this issue with the airplane manufacturer and the Luftsfartsverket (LFV), the airworthiness authority for Sweden.

The FAA does not concur. Based on historical and current data received from the LFV and the airplane manufacturer, false (nuisance) warnings from the existing smoke detector continue to be a significant safety concern. The FAA acknowledges the commenter's statement that modification of the existing smoke detector via Fenwall Service Bulletin #9701 has resulted in some improvement in reliability. However, the commenter did not provide data to substantiate this statement. Additionally, the LFV advises that bench and field tests conducted with both the modified Fenwall smoke detector and the Cerberus smoke detector have shown the Cerberus unit to have a much higher reliability with respect to nuisance warnings. The Cerberus smoke detector incorporates new technology, i.e., a microprocessor intended to better distinguish between smoke conditions and high humidity conditions. With this information, the FAA has determined that installation of the Cerberus smoke detectors is necessary to adequately address the identified unsafe condition, and does not consider it necessary to delay issuance of the final rule. No change is made to the final rule.

Conclusion

After careful review of the available data, including the comment noted above, the FAA has determined that air safety and the public interest require the adoption of the rule as proposed.

Cost Impact

The FAA estimates that 289 airplanes of U.S. registry will be affected by this AD, that it will take approximately 2 work hours per airplane to accomplish the required actions, and that the average labor rate is $60 per work hour. Required parts will cost between $2,011 and $4,022 per airplane. Based on these figures, the cost impact of the AD on U.S. operators is estimated to be between $2,131 and $4,142 per airplane.

The cost impact figure discussed above is based on assumptions that no operator has yet accomplished any of the 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 adopted herein will 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 final rule does not have federalism implications under Executive Order 13132.

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 final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it 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.

§ 39.13

[Amended]

2. Section 39.13 is amended by adding the following new airworthiness directive:

2000-14-03 SAAB Aircraft AB: Amendment 39-11812. Docket 2000-NM-23-AD.

Applicability: Model SAAB SF340A series airplanes, manufacturer's serial numbers 004 through 159 inclusive; and Model SAAB 340B series airplanes, manufacturer's serial numbers 160 through 459 inclusive; 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 (b) 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 false smoke warnings from the cargo compartment smoke detectors, which could result in aborted takeoffs, diversions of flight routes, and emergency evacuation of flight crew and passengers, accomplish the following:

Replacement

(a) Within 2 years after the effective date of this AD, replace the smoke detectors in the cargo compartment with new, improved smoke detectors, in accordance with Saab Service Bulletin 340-26-023, dated December 21, 1999.

Alternative Methods of Compliance

(b) 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 2:

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

(c) 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.

Incorporation by Reference

(d) The actions shall be done in accordance with Saab Service Bulletin 340-26-023, dated December 21, 1999. 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 Saab Aircraft AB, SAAB Aircraft Product Support, S-581.88, Linköping, Sweden. Copies may be 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.

Note 3:

The subject of this AD is addressed in Swedish airworthiness directive 1-151, dated December 28, 1999.

(e) This amendment becomes effective on August 17, 2000.

Issued in Renton, Washington, on July 3, 2000.

Vi L. Lipski,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.