Airworthiness directives: Fokker,

[Federal Register: November 23, 1998 (Volume 63, Number 225)]

[Proposed Rules]

[Page 64656-64657]

From the Federal Register Online via GPO Access [wais.access.gpo.gov]

[DOCID:fr23no98-29]

[[Page 64656]]

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-279-AD]

RIN 2120-AA64

Airworthiness Directives; Fokker Model F.28 Mark 0070 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

SUMMARY: This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Fokker Model F.28 Mark 0070 series airplanes. This proposal would require modification of the power supply system of the horizontal stabilizer control unit. 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 the loss of primary hydraulic stabilizer control during use of certain emergency procedures, which could result in the inability of the flight crew to control the airplane.

DATES: Comments must be received by December 23, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 98-NM-279-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 Fokker Services B.V., Technical Support Department, P.O. Box 75047, 1117 ZN Schiphol Airport, The Netherlands. 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 filedin 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 98-NM-279-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. 98-NM-279-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

The Rijksluchtvaartdienst (RLD), which is the airworthiness authority for The Netherlands, notified the FAA that an unsafe condition may exist on certain Fokker Model F.28 Mark 0070 series airplanes. The RLD advises that the existing design of certain horizontal stabilizer control units (HSCU) will result in the HSCU being inoperative if both the No. 1 and No. 2 direct current (DC) buses are de-energized, either as a result of malfunction or if certain emergency procedures are used by the flight crew. If the HSCU is inoperative, only alternate stabilizer control is available, and the flight crew must operate the ``ALT STAB'' switch for pitch trim control. A recent assessment has resulted in a determination that use of alternate stabilizer control alone may not be sufficient for pitch control during certain emergency procedures. Such loss of the primary hydraulic stabilizer control during use of certain emergency procedures, if not corrected, could result in the inability of the flight crew to control the airplane.

Explanation of Relevant Service Information

Fokker has issued Service Bulletin SBF100-27-071, dated December 21, 1996, which describes procedures for modification of the power supply system of the HSCU. The modification involves removal of the circuit breaker, placard, and associated wiring; and installation of a new circuit breaker, placard, and associated wiring. Accomplishment of the actions specified in the service bulletin is intended to adequately address the identified unsafe condition. The RLD classified this service bulletin as mandatory and issued Dutch airworthiness directive BLA 1996-158 (A), dated December 31, 1996, in order to assure the continued airworthiness of these airplanes in The Netherlands.

FAA's Conclusions

This airplane model is manufactured in the Netherlands 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 RLD has kept the FAA informed of the situation described above. The FAA has examined the findings of the RLD, 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 require accomplishment of the actions specified in the service bulletin described previously.

Cost Impact

The FAA estimates that 2 airplanes of U.S. registry would be affected by this proposed AD, that it would take approximately 4 work hours per airplane to accomplish the proposed modification, and that the average labor rate is $60 per work hour. Required parts would cost approximately $350 per airplane. Based on these figures, the cost impact of the modification proposed by this AD on U.S. operators is estimated to be $1,180, or $590 per airplane.

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The cost impact figure discussed above is 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 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.

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.

   Sec. 39.13 [Amended]

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

   Fokker Services B.V.: Docket 98-NM-279-AD.

   Applicability: Model F.28 Mark 0070 series airplanes, as listed in Fokker Service Bulletin SBF100-27-071, dated December 21, 1996; 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 the loss of primary hydraulic stabilizer control during use of certain emergency procedures, which could result in the inability of the flight crew to control the airplane, accomplish the following:

   (a) Within 12 months after the effective date of this AD, modify the power supply system of the horizontal stabilizer control unit in accordance with Fokker Service Bulletin SBF100-27-071, dated December 21, 1996.

   (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.

   (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.

   Note 3: The subject of this AD is addressed in Dutch airworthiness directive BLA 1996-158 (A), dated December 31, 1996.

   Issued in Renton, Washington, on November 16, 1998. Darrell M. Pederson, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.

   [FR Doc. 98-31176Filed11-20-98; 8:45 am]

   BILLING CODE 4910-13-U