Airworthiness directives: Mooney Aircraft Corp.,

[Federal Register: June 17, 1998 (Volume 63, Number 116)]

[Proposed Rules]

[Page 33016-33017]

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

[DOCID:fr17jn98-20]

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-CE-47-AD]

RIN 2120-AA64

Airworthiness Directives; Mooney Aircraft Corporation Models M20J, M20K, M20M, and M20R Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

SUMMARY: This document proposes to adopt a new airworthiness directive (AD) that would apply to certain Mooney Aircraft Corporation (Mooney) Models M20J, M20K, M20M, and M20R airplanes. The proposed AD would require grinding the surface of the main landing gear (MLG) leg bracket, inspecting this area for cracks, and replacing any cracked MLG leg bracket. The proposed AD is the result of the manufacturing of several of the MLG leg brackets using laser pattern cutting. The brackets, when manufactured using this process, develop minor cracks at the bends, which could propagate over time. The actions specified by the proposed AD are intended to prevent failure of the MLG side brace bolt caused by cracking of the MLG leg bracket, which could result in MLG collapse with consequent loss of control of the airplane during taxi, takeoff, or landing operations.

DATES: Comments must be received on or before August 21, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation Administration (FAA), Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 98-CE-47-AD, Room 1558, 601 E. 12th Street, Kansas City, Missouri 64106. Comments may be inspected at this location between 8 a.m. and 4 p.m., Monday through Friday, holidays excepted.

Service information that applies to the proposed AD may be obtained from Mooney Aircraft Corporation, Louis Schreiner Field, Kerrville, Texas 78028. This information also may be examined at the Rules Docket at the address above.

FOR FURTHER INFORMATION CONTACT: Mr. Bob D. May, Aerospace Engineer, FAA, Airplane Certification Office, 2601 Meacham Boulevard, Fort Worth, Texas 76193-0150; telephone: (817) 222-5156; facsimile: (817) 222-5960.

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 should 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 that summarizes 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 No. 98-CE-47-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, Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 98-CE-47-AD, Room 1558, 601 E. 12th Street, Kansas City, Missouri 64106.

Discussion

The FAA has received a report that the design service life of the part number (P/N) 510010 MLG leg bracket on certain Mooney Models M20J, M20K, M20M, and M20R airplanes may not be achieved. Eleven of these brackets were produced using a laser pattern cutting process. The brackets, when manufactured using this process, develop minor cracks at the bends, which could propagate over time.

The P/N 510010 bracket supports the MLG side brace bolt. Failure of the MLG side brace bolt would cause the MLG to collapse with consequent loss of control of the airplane during taxi, takeoff, or landing operations.

Relevant Service Information

Mooney has issued Service Bulletin M20-265, dated 1April 13, 1998, which specifies procedures for grinding the surface of the MLG leg bracket, P/N 510010, and inspecting this area for cracks.

The FAA's Determination

After examining the circumstances and reviewing all available information related to the incidents described above, including the referenced service information, the FAA has determined that AD action should be taken to prevent failure of the MLG side brace bolt caused by cracking of the MLG leg

[[Page 33017]]

bracket. This could result in MLG collapse with consequent loss of control of the airplane during taxi, takeoff, or landing operations.

Explanation of the Provisions of the Proposed AD

Since an unsafe condition has been identified that is likely to exist or develop in other Mooney Models M20J, M20K, M20M, and M20R airplanes of the same type design, the FAA is proposing AD action. The proposed AD would require grinding the surface of the MLG leg bracket, P/N 510010; inspecting this area for cracks; and replacing any cracked MLG leg bracket.

Accomplishment of the surface grinding and inspection would be required in accordance with Mooney Service Bulletin M20-265, dated April 13, 1998.

Replacement of any cracked MLG leg bracket, if required, would be accomplished in accordance with the applicable maintenance manual.

Cost Impact

The FAA estimates that 11 airplanes in the U.S. registry would be affected by the proposed AD, that it would take approximately 8 workhours per airplane to accomplish the proposed actions, and that the average labor rate is approximately $60 an hour. Based on these figures, the total cost impact of the proposed AD on U.S. operators is estimated to be $5,280, or $480 per airplane. These figures are based on the presumption that no affected airplane owner/operator has accomplished the proposed actions. These figures do not account for the cost of any necessary replacement if any MLG leg bracket is found cracked. The FAA has no way of determining how many MLG leg brackets may be found cracked during the proposed inspection.

Mooney will provide warranty credit for up to 8 workhours that are necessary to comply with the requirements of the proposed AD. Details are provided in Mooney Service Bulletin M20-265, dated April 13, 1998.

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 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) 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 has been placed 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 a new airworthiness directive (AD) to read as follows:

   Mooney Aircraft Corporation: Docket No. 98-CE-47-AD.

   Applicability: The following airplane models and serial numbers, certificated in any category:

   Models

   Serial Numbers

   M20J

   24-3415 and 24-3416.

   M20K

   25-2018 through 25-2021.

   M20M

   27-0241.

   M20R

   29-0135 through 29-0138.

   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 (d) 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 in the body of this AD, unless already accomplished.

   To prevent failure of the main landing gear (MLG) side brace bolt caused by cracking of the MLG leg bracket, which could result in MLG collapse with consequent loss of control of the airplane during taxi, takeoff, or landing operations, accomplish the following:

   (a) Within the next 100 hours time-in-service (TIS) after the effective date of this AD, accomplish the following in accordance with the INSTRUCTIONS section of Mooney Service Bulletin M20-265, dated April 13, 1998:

   (1) Grind the surface of the MLG leg bracket, part number (P/N) 510010.

   (2) Inspect the area of the P/N 510010 MLG leg bracket for cracks.

   (b) Prior to further flight after the inspection required by paragraph (a)(2) of this AD, replace any cracked P/N 510010 MLG leg bracket with a new P/N 510010 MLG leg bracket. Accomplish this replacement in accordance with the applicable maintenance manual.

   (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.

   (d) An alternative method of compliance or adjustment of the compliance times that provides an equivalent level of safety may be approved by the Manager, Fort Worth Airplane Certification Office (ACO), 2601 Meacham Boulevard, Fort Worth, Texas 76193-0150. The request shall be forwarded through an appropriate FAA Maintenance Inspector, who may add comments and then send it to the Manager, Fort Worth ACO.

   Note 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Fort Worth ACO.

   (e) All persons affected by this directive may obtain copies of the document referred to herein upon request to Mooney Aircraft Corporation, Louis Schreiner Field, Kerrville, Texas 78028; or may examine this document at the FAA, Central Region, Office of the Regional Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri 64106.

   Issued in Kansas City, Missouri, on June 10, 1998. Michael Gallagher, Manager, Small Airplane Directorate, Aircraft Certification Service.

   [FR Doc. 98-16025Filed6-16-98; 8:45 am]

   BILLING CODE 4910-13-U