Airworthiness directives: Cessna,

[Federal Register: November 4, 1999 (Volume 64, Number 213)]

[Proposed Rules]

[Page 60136-60138]

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

[DOCID:fr04no99-20]

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-218-AD]

RIN 2120-AA64

Airworthiness Directives; Cessna Model 750 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 Cessna Model 750 airplanes. This proposal would require replacement of reset circuit breakers for the auxiliary hydraulic pump system and the King KHF 950 high frequency communication system(s) with new circuit breakers. This proposal is prompted by a report from the airplane manufacturer indicating that the trip levels for the reset circuit breakers installed in the auxiliary hydraulic pump system and the King KHF 950 high frequency system(s) are too high, which can prevent corresponding high current remote control circuit breakers from tripping when excessive electrical loads are present. The actions specified by the proposed AD are intended to prevent overloading of the affected airplane electrical wiring and circuits, which could result in a fire.

DATES: Comments must be received by December 20, 1999.

ADDRESSES: Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 99-NM-218-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 Cessna Aircraft Co., P.O. Box 7706, Wichita, Kansas 67277. This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Small Airplane Directorate, Wichita Aircraft Certification Office, 1801 Airport Road, Room 100, Mid-Continent Airport, Wichita, Kansas.

FOR FURTHER INFORMATION CONTACT: Raymond Johnston, Aerospace Engineer, Systems and Propulsion Branch, ACE-

[[Page 60137]]

116W, FAA, Small Airplane Directorate, Wichita Aircraft Certification Office, 1801 Airport Road, Room 100, Mid-Continent Airport, Wichita, Kansas 67209; telephone (316) 946-4151; fax (316) 946-4407.

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 99-NM-218-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-218-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

The FAA has received a report from the manufacturer of Cessna Model 750 airplanes indicating that the trip levels for the reset circuit breakers installed in the auxiliary hydraulic pump system and the King KHF 950 high frequency communication system(s) are too high. Investigation has revealed that engineering drawings incorrectly called out 5.0-ampere reset circuit breakers instead of 0.5-ampere reset circuit breakers. This condition can prevent the reset circuit breakers' corresponding high current remote control circuit breakers from tripping when excessive electrical loads are present. This condition, if not corrected, could lead to overloading of the affected airplane electrical wiring and circuits, and a possible fire.

Explanation of Relevant Service Information

The FAA has reviewed and approved Cessna Service Bulletin SB750-24- 15, Revision 1, dated May 24, 1999, which describes procedures for replacement of the 5.0-ampere reset circuit breakers for the auxiliary hydraulic pump system and the King KHF 950 high frequency communication systems, with 0.5-ampere circuit breakers. Accomplishment of the actions specified in this service bulletin is intended to adequately address the identified unsafe condition.

Explanation of Requirements of Proposed Rule

Since an unsafe condition has been identified that is likely to exist or develop on other products of this same type design, the proposed AD would require accomplishment of the actions specified in the service bulletin described previously.

Cost Impact

There are approximately 82 airplanes of the affected design in the worldwide fleet. The FAA estimates that 80 airplanes of U.S. registry would be affected by this proposed AD, that it would take approximately 3 work hours per airplane to accomplish the proposed replacement, and that the average labor rate is $60 per work hour. The airplane manufacturer has committed previously to its customers that it will bear the cost of replacement parts. As a result, the costs of those parts are not attributable to this proposed AD. Based on these figures, the cost impact of the proposed AD on U.S. operators is estimated to be $14,400, or $180 per airplane.

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. However, the FAA has been advised that manufacturer warranty remedies are available for parts and labor costs associated with accomplishing the actions required by this proposed AD. Therefore, the future economic cost impact of this rule on U.S. operators may be less than the cost impact figure indicated above.

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:

   Cessna Aircraft Company: Docket 99-NM-218-AD.

   Applicability: Model 750 airplanes, serial numbers -0001 through -0100 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

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   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 overloading of certain airplane electrical wiring and circuits, which could result in a fire, accomplish the following:

   Replacement

   (a) Within 90 days after the effective date of this AD, replace the 5.0-ampere reset circuit breakers for the auxiliary hydraulic pump system and the King KHF 950 high frequency communication system(s) with 0.5-ampere reset circuit breakers, in accordance with Cessna Service Bulletin SB750-24-15, Revision 1, dated May 24, 1999.

   Note 2: Circuit breaker replacement accomplished prior to the effective date of this AD in accordance with Cessna Service Bulletin SB750-24-15, dated May 7, 1999, is considered acceptable for compliance with the applicable action specified in this amendment.

   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, Wichita Aircraft Certification Office (ACO), FAA, Small 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, Wichita ACO.

   Note 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Wichita ACO.

   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.

   Issued in Renton, Washington, on October 29, 1999. D. L. Riggin, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.

   [FR Doc. 99-28848Filed11-3-99; 8:45 am]

   BILLING CODE 4910-13-U