[Federal Register Volume 63, Number 116 (Wednesday, June 17, 1998)]
[Proposed Rules]
[Pages 33016-33017]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-16025]


-----------------------------------------------------------------------

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 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 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. 98-16025 Filed 6-16-98; 8:45 am]
BILLING CODE 4910-13-U