[Federal Register Volume 65, Number 210 (Monday, October 30, 2000)]
[Proposed Rules]
[Pages 64640-64642]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-27755]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000-CE-24-AD]
RIN 2120-AA64


Airworthiness Directives; Cessna Aircraft Company Model 172RG 
Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes to adopt a new airworthiness directive 
(AD) that would apply to certain Cessna Aircraft Company (Cessna) Model 
172 airplanes. The proposed AD would require you to inspect the main 
landing gear pivot assemblies for cracks, replace any cracked main 
landing gear pivot assemblies, and install new bushings on the pivot 
assembly shaft. Many service difficulty reports of cracked main landing 
gear pivot assemblies on the affected airplanes prompted the proposed 
action. The actions specified by the proposed AD are intended to 
detect, correct, and prevent future cracks on the original design 
landing gear pivots. Cracked main landing gear pivots could fail 
resulting in gear-up landings or loss of braking.

DATES: The Federal Aviation Administration (FAA) must receive any 
comments on this proposed rule by December 7, 2000.

ADDRESSES: Send comments in triplicate to the Federal Aviation 
Administration (FAA), Central Region, Office of the Regional Counsel, 
Attention: Rules Docket No. 2000-CE-24-AD, 901 Locust, Room 506, Kansas 
City, Missouri 64106. You may read comments at this location between 8 
a.m. and 4 p.m., Monday through Friday, except holidays.
    You may get the service information referenced in this proposed AD 
from the Cessna Aircraft Company, Product Support, P.O. Box 7706, 
Wichita, Kansas 67277; telephone: (316) 517-5800; facsimile: (316) 942-
9006. You may examine this information at the Rules Docket at the above 
address.

FOR FURTHER INFORMATION CONTACT: Steven Litke, Aerospace Engineer, 
Wichita Aircraft Certification Office, FAA, 1801 Airport Road, Mid-
Continent Airport, Wichita, Kansas 67209; telephone: (316) 946-4127; 
facsimile: (316) 946-4407.

SUPPLEMENTARY INFORMATION:

[[Page 64641]]

Comments Invited

    How do I comment on the proposed AD? We invite your comments on the 
proposed rule. You may send whatever written data, views, or arguments 
you choose. You need to include the rule's docket number and send your 
comments in triplicate to the address named under the caption 
ADDRESSES. We will consider all comments received by the closing date 
named above, before taking action on the proposed rule. We may change 
the proposals contained in this notice because of the comments 
received.
    Are there any specific portions of the proposed AD I should pay 
attention to? The FAA specifically invites comments on the overall 
regulatory, economic, environmental, and energy aspects of the proposed 
rule that might call for a need to change the proposed rule. You may 
examine all comments we receive before and after the closing date for 
comments in the Rules Docket. We will file a report in the Rules Docket 
that summarizes each FAA contact with the public that concerns the 
substantive parts of this proposal.
    The FAA is reexamining the writing style we currently use in 
regulatory documents, in response to the Presidential memorandum of 
June 1, 1998. That memorandum requires federal agencies to communicate 
more clearly with the public. We want to read your comments on the ease 
of understanding this document, and any other suggestions you might 
have to improve the clarity of FAA communications that affect you. You 
can get more information about the Presidential memorandum and the 
plain language initiative at http://www.faa.gov/language/.
    How can I be sure FAA receives my comment? If you want us to 
acknowledge the receipt of your comments, you must include a self-
addressed, stamped postcard. On the postcard, write ``Comments to 
Docket No. 2000-CE-24-AD.'' We will date stamp and mail the postcard 
back to you.

Discussion

    What events have caused this proposed AD? The FAA has received many 
service difficulty reports of failures of pivot assemblies on Cessna 
Model 172RG airplanes. Failure of the main landing gear pivots has 
resulted in gear-up landings or loss of braking. The end of the pivot 
experiences overload stresses because of improper bushing clearance. 
This stress can produce fatigue cracks that spread until the pivot 
fitting fails, preventing the landing gear from extending. In other 
cases, brake fluid leaks through the fatigue crack resulting in loss of 
braking action.
    What are the consequences if the condition is not corrected? 
Original design landing gear pivots, if not replaced with improved 
pivots, could crack and fail, resulting in gear-up landings or loss of 
braking.

Relevant Service Information

    Is there service information that applies to this subject? Cessna 
has issued Service Bulletin SEB90-1, Revision 3, dated March 15, 1999.
    What are the provisions of this service bulletin? The service 
bulletin contains procedures for:
--Inspecting the main landing gear pivot assemblies for cracks,
--Replacing any cracked main landing gear pivot assemblies, and
--Installing new bushings on the pivot assembly shaft.

The FAA's Determination and an Explanation of the Provisions of the 
Proposed AD

    What has FAA decided? After examining the circumstances and 
reviewing all available information related to the incidents, we have 
determined that:
--The unsafe condition referenced in this document exists or could 
develop on other Cessna Model 172RG airplanes of the same type design;
--These airplanes should have the actions named in the service bulletin 
incorporated; and
--The FAA should take AD action to correct this unsafe condition.
    What would this proposed AD require? This proposed AD would require 
you to follow the Cessna Service Bulletin SEB90-1, Revision 3, dated 
March 15, 1999, and the Model 172RG Series Service Manual and do these 
actions:
--Inspect the main landing gear pivot assemblies for cracks;
--Replace any cracked main landing gear pivot assemblies; and
--Install new bushings on the pivot assembly shaft.

Cost Impact

    How many airplanes would this proposed AD impact? We estimate the 
proposed AD would affect 766 airplanes in the U.S. registry.
    What would be the cost impact of the proposed actions for the 
affected airplanes on the U.S. Register? We estimate that it would take 
about 20 workhours for each airplane to do both proposed pivot assembly 
inspections, at an average labor rate of $60 an hour. Based on the 
figures presented above, we estimate the total cost impact of the 
proposed inspection on U.S. operators is $919,200, or $1,200 for each 
airplane.
    We estimate that it would take about 5 workhours for each airplane 
to do both proposed bushing replacements concurrent with the pivot 
assembly inspection, at an average labor rate of $60 an hour. Parts 
cost about $200 for each airplane. Based on the figures presented 
above, we estimate the total cost impact of the proposed bushing 
replacement on U.S. operators is $500 for each airplane.
    If a crack is found during the pivot assembly inspection, the pivot 
assembly must be replaced. We estimate that it would take about 3 
workhours to do each proposed pivot assembly replacement, at an average 
labor rate of $60 an hour. Parts cost about $2,783 for each pivot 
assembly. Based on the figures presented above, we estimate the total 
cost impact of the proposed pivot assembly replacement on U.S. 
operators is $2,963 for each pivot assembly.
    We have no way of knowing how many airplanes will require 
replacement pivot assemblies. The total cost for each airplane for this 
proposed AD depends on whether a crack is found during the inspection 
of the pivot assembly. We estimate the total cost impact of this AD for 
each airplane to U.S. operators is:

------------------------------------------------------------------------
                                                 One pivot   Both pivots
             Neither pivot cracked                cracked      cracked
------------------------------------------------------------------------
$1700.........................................        $4663        $7626
------------------------------------------------------------------------

Regulatory Impact

    Would this proposed AD impact relations between Federal and State 
governments? The regulations proposed would not have a substantial 
direct effect on the States, between the national government and the 
States, or on the distribution of power and responsibilities among the 
various levels of government. We have determined that this proposed 
rule would not have federalism implications under Executive Order 
13132.
    Would this proposed AD involve a significant rule or regulatory 
action? 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 put into 
effect, 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. We have placed a copy of the draft 
regulatory evaluation prepared for this action in the Rules Docket. You 
may get

[[Page 64642]]

a copy of it 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

    Therefore, under the authority delegated to me by the 
Administrator, the Federal Aviation Administration (FAA) 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. FAA amends Section 39.13 by adding a new airworthiness directive 
(AD) to read as follows:

 Cessna Aircraft Company: Docket No. 2000-CE-24-AD.

    (a) What airplanes are affected by this AD? Model 172RG, with 
the serial numbers 691 and 172RG0001 through 172RG1191, certified in 
any category.
    (b) Who must comply with this AD? Anyone who wishes to operate 
any of the above airplanes must comply with this AD.
    (c) What problem does this AD address? The actions specified in 
this AD are intended to detect, correct, and prevent future cracks 
on the original design landing gear pivots. Cracked main landing 
gear pivots could fail, resulting in gear-up landings or loss of 
braking.
    (d) What must I do to address this problem? To address this 
problem, you must do the following actions:

------------------------------------------------------------------------
             Actions               Compliance times       Procedures
------------------------------------------------------------------------
(1) Inspect the main landing      Within the next     Do this action
 gear pivot assemblies for         100 time-           following the
 cracks.                           inservice after     ACCOMPLISHMENT
                                   the effective       INSTRUCTIONS in
                                   date of this AD.    Cessna Service
                                                       Bulletin SEB90-1,
                                                       Revision 3, dated
                                                       March 15, 1999,
                                                       and the Model
                                                       172RG Series
                                                       Service Manual.
(2) If you find cracks, replace   Before further      Do this action
 the affected main landing gear    flight after the    following the
 pivot assembly with the part      inspection.         ACCOMPLISHMENT
 referenced in the service                             INSTRUCTIONS in
 bulletin.                                             Cessna Service
                                                       Bulletin SEB90-1,
                                                       Revision 3, dated
                                                       March 15, 1999,
                                                       and the Model
                                                       172RG Series
                                                       Service Manual.
(3) Install new bushings on both  Before further      Do this action
 main landing gear pivot           flight after the    following the
 assemblies using the applicable   inspection.         ACCOMPLISHMENT
 kit referenced in the service                         INSTRUCTIONS in
 bulletin.                                             Cessna Service
                                                       Bulletin SEB90-1,
                                                       Revision 3, dated
                                                       March 15, 1999,
                                                       and the Model
                                                       172RG Series
                                                       Service Manual.
------------------------------------------------------------------------

    (e) Can I comply with this AD in any other way? You may use an 
alternative method of compliance or adjust the compliance time if:
    (1) Your alternative method of compliance provides an equivalent 
level of safety; and
    (2) The Manager, Wichita Aircraft Certification Office (ACO), 
approves your alternative. Send your request through an FAA 
Principal Maintenance Inspector, who may add comments and then send 
it to the Manager, Wichita ACO.

    Note: This AD applies to each airplane identified in paragraph 
(a) of this AD, 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 the 
performance of the requirements of this AD is affected, the owner/
operator must request approval for an alternative method of 
compliance under paragraph (e) 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 you 
have not eliminated the unsafe condition, specific actions you 
propose to address it.

    (f) Where can I get information about any already-approved 
alternative methods of compliance? Contact Steven Litke, Aerospace 
Engineer, Wichita Aircraft Certification Office, FAA, 1801 Airport 
Road, Mid-Continent Airport, Wichita, Kansas 67209; telephone: (316) 
946-4127; facsimile: (316) 946-4407.
    (g) What if I need to fly the airplane to another location to 
comply with this AD? The FAA can issue a special flight permit under 
Secs. 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 
21.197 and 21.199) to operate your airplane to a location where you 
can do the requirements of this AD.
    (h) How do I get copies of the documents referenced in this AD? 
You may get copies of the documents referenced in this AD from the 
Cessna Aircraft Company, Product Support, P.O. Box 7706, Wichita, 
Kansas 67277; or read this document at FAA, Central Region, Office 
of the Regional Counsel, 901 Locust, Room 506, Kansas City, Missouri 
64106.

    Issued in Kansas City, Missouri, on October 23, 2000.
Marvin R. Nuss,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 00-27755 Filed 10-27-00; 8:45 am]
BILLING CODE 4910-13-U