[Federal Register Volume 66, Number 62 (Friday, March 30, 2001)]
[Rules and Regulations]
[Pages 17345-17348]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-7831]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2001-CE-14-AD; Amendment 39-12164; AD 2001-06-17]
RIN 2120-AA64


Airworthiness Directives; Cessna Aircraft Company Models 172R and 
172S Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
applies to certain Cessna Aircraft Company (Cessna) Models 172R and 
172S airplanes. This AD requires a one-time inspection for proper 
engine idle speed and fuel control mixture setting and adjustment, as 
necessary. This AD also requires incorporating engine operating 
procedures into the pilots operating handbook (POH) and FAA-approved 
airplane flight manual (AFM). This AD is the result of reports of rough 
engine operation because of an over-rich fuel mixture (improper fuel 
flow settings). The actions specified by this AD are intended to detect 
and correct such improper fuel flow settings, which could result in 
rough engine operation or engine stoppage. This over-rich fuel mixture 
also contributes to the engine not restarting during flight when using 
published in-flight restart procedures.

DATES: This AD becomes effective on April 20, 2001.
    The Federal Aviation Administration (FAA) must receive any comments 
on this rule on or before May 18, 2001.

ADDRESSES: Submit comments in triplicate to FAA, Central Region, Office 
of the Regional Counsel, Attention: Rules Docket No. 2001-CE-14-AD, 901 
Locust, Room 506, Kansas City, Missouri 64106.
    You may examine information related to this AD at FAA, Central 
Region, Office of the Regional Counsel, Attention: Rules Docket No. 
2001-CE-14-AD, 901 Locust, Room 506, Kansas City, Missouri 64106.

FOR FURTHER INFORMATION CONTACT: Mr. Paul Pendleton, Aerospace 
Engineer, Wichita Aircraft Certification Office, FAA, 1801 Airport 
Road, Mid-Continent Airport, Wichita, Kansas 67209; telephone: (316) 
946-4143; facsimile: (316) 946-4407.

SUPPLEMENTARY INFORMATION:

Discussion

    What events have caused this AD? The FAA has received several 
reports of improper engine fuel flow settings on Cessna Models 172R and 
172S airplanes. These improper settings could prevent the engine from 
operating at idle speed when the pilot reduces power (i.e., landing 
approach, power off stalls, etc.). An over-rich fuel mixture is a 
reason why the engine may not operate at idle speed. This over-rich 
fuel mixture also contributes to the engine not restarting during 
flight when using published in-flight restart procedures.
    The current pilot operating handbook (POH) and FAA-approved 
airplane flight manual (AFM) procedures for the Cessna Models 172R and 
172S airplanes do not address the pilot bringing the throttle back to 
the hard idle stop (throttle full aft). The POH/AFM also does not 
address emergency engine restart procedures to enable engine startup if 
a rich fuel mixture exists.
    What are the consequences if the condition is not corrected? This 
condition, if not corrected, could result in rough engine operation or 
engine stoppage. The over-rich fuel mixture also contributes to the 
engine not restarting during flight when using published in-flight 
restart procedures.

FAA's Determination and an Explanation of the Provisions of this AD

    What has FAA decided? The FAA has reviewed all available 
information and determined that:

--The unsafe condition referenced in this document exists or could 
develop on other Cessna Models 172R and 172S airplanes of the same type 
design;
--These airplanes should be inspected for proper engine idle speed and 
fuel control mixture setting, the engine idle speed or fuel control 
mixture setting should be adjusted as necessary, and engine operating 
procedures should be incorporated into the POH/AFM; and
--AD action should be taken in order to correct this unsafe condition.

    Is there service information that applies to this subject? Cessna 
has issued Service Bulletin SB01-11-02,

[[Page 17346]]

dated March 5, 2001. This service bulletin:

--Includes procedures for inspecting the engine idle speed; and
--Specifies pilot operating procedure changes.

    What does this AD require? This AD requires a one-time inspection 
for proper engine idle speed and fuel control mixture setting and 
adjustment, as necessary. This AD also requires incorporating engine 
operating procedures into the POH/AFM.
    Procedures for accomplishing the inspection are included in the AD. 
We are not utilizing the procedures included in Cessna Service Bulletin 
SB01-11-02, dated March 5, 2001.
    Why is FAA not requiring the actions specified in the service 
bulletin? The inspection procedures in Cessna Service Bulletin SB01-11-
02 agree with the service manual procedures. The procedures we are 
including in this AD agree with the Cessna factory production 
procedures. After examining these procedures, FAA has determined that:

--The procedures in the service bulletin and service manual procedures 
are too restrictive for a pilot to accomplish in the field without 
using specialized equipment (portable electric tachometer);
--The pilot should be able to accomplish the inspection for proper 
engine idle speed and fuel control mixture setting; and
--The inspection procedures in this AD allow the pilot to both easily 
accomplish the inspection and address the safety intent of this AD.

    Will I have the opportunity to comment prior to the issuance of the 
rule? Because the unsafe condition described in this could result in 
rough engine operation or engine stoppage, FAA finds that notice and 
opportunity for public prior comment are impracticable. Therefore, good 
cause exists for making this amendment effective in less than 30 days.

Comments Invited

    How do I comment on this AD? Although this action is in the form of 
a final rule and was not preceded by notice and opportunity for public 
comment, we invite your comments on the rule. You may submit whatever 
written data, views, or arguments you choose. You need to include the 
rule's docket number and submit your comments in triplicate to the 
address specified under the caption ADDRESSES. We will consider all 
comments received on or before the closing date specified above. We may 
amend this rule in light of comments received. Factual information that 
supports your ideas and suggestions is extremely helpful in evaluating 
the effectiveness of the AD action and determining whether we need to 
take additional rulemaking action.
    Are there any specific portions of the AD that FAA wants me to 
address? The FAA specifically invites comments on the overall 
regulatory, economic, environmental, and energy aspects of the rule 
that might suggest a need to modify the rule. You may examine all 
comments we receive before and after the closing date of the rule 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 AD.
    We are reviewing 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 are interested in your comments on whether the 
style of this document is clear, 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.plainlanguage.gov.
    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. 2001-CE-14-AD.'' We will date stamp and mail the postcard 
back to you.

Regulatory Impact

    Does this AD impact various entities? These regulations will not 
have a substantial direct effect 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, FAA has determined that this final rule does not have 
federalism implications under Executive Order 13132.
    Does this AD involve a significant rule or regulatory action? The 
FAA has determined that this regulation is an emergency regulation that 
must be issued immediately to correct an unsafe condition in aircraft, 
and is not a significant regulatory action under Executive Order 12866. 
It has been determined further that this action involves an emergency 
regulation under DOT Regulatory Policies and Procedures (44 FR 11034, 
February 26, 1979). If it is determined that this emergency regulation 
otherwise would be significant under DOT Regulatory Policies and 
Procedures, a final regulatory evaluation will be prepared and placed 
in the Rules Docket (otherwise, an evaluation is not required). A copy 
of it, if filed, may be obtained from the Rules Docket.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

Adoption of the Amendment

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

2001-06-14  Cessna Aircraft Company: Amendment 39-12164; Docket No. 
2001-CE-14-AD.

    (a) What airplanes are affected by this AD? This AD applies to 
Models 172R and 172S, all serial numbers, that are certificated 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 by 
this AD are intended to detect and correct an over-rich fuel mixture 
(improper fuel flow settings), which could result in rough engine 
operation or engine stoppage. This over-rich fuel mixture also 
contributes to the engine not restarting during flight when using 
published in-flight restart procedures.
    (d) What must I do to address this problem? To address this 
problem, you must accomplish the following actions:

[[Page 17347]]



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               Action                            Compliance time                    Special instructions
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(1) Accomplish one of the following   Within the next 10 hours time-in-     The owner/operator holding at least
 inspections for proper engine idle    service (TIS) after April 20, 2001    a private pilot certificate as
 speed and fuel control mixture        (the effective date of this AD),      authorized by section 43.7 of the
 setting:                              unless already accomplished.          Federal Aviation Regulations (14
(i) Pilot Procedure: Accomplish the                                          CFR 43.7) may accomplish the
 inspection with the engine oil                                              inspection specified in paragraph
 temperature between 120 and 150                                             (d)(1)(i) of this AD. Make an entry
 degrees Fahrenheit (F). Assure that                                         into the aircraft records showing
 the engine idle setting is between                                          compliance with this portion of the
 575 and 625 revolutions per minute                                          AD in accordance with section 43.9
 (RPM) and the mixture setting will                                          of the Federal Aviation Regulations
 produce a minimum 10 RPM rise and a                                         (14 CFR 43.9). You may need to
 maximum 50 RPM rise with the                                                accomplish seasonal adjustments of
 throttle at the hard ground idle                                            the engine idle speed setting.
 stop. Screw the vernier mixture out                                         These seasonal adjustments should
 slowly counterclockwise to obtain                                           not be included in your already
 the RPM rise.                                                               established 12-month scheduled
(ii) Mechanic Procedure: Accomplish                                          adjustments.
 the inspection with the engine oil
 temperature between 120 and 150
 degrees F. Assure that the fuel
 mixture setting is between 575 and
 625 RPM and the mixture setting
 will produce a minimum 10 RPM rise
 and a maximum 20 RPM rise with the
 throttle at the hard ground idle
 stop. Screw the vernier mixture out
 slowly counterclockwise. The reason
 the limits are different than the
 pilot procedure is that the
 mechanic needs to establish a more
 accurate RPM indicator than the
 airplanes engine RPM gage. You will
 most likely need to use an electric
 tachometer to verify speed changes.
(2) If, during any inspection         Accomplish the adjustment (if         If you have to adjust the servo more
 required by this AD, proper engine    required) prior to further flight     than twice over a 12-month period,
 idle speed and fuel control mixture   after the inspection required by      obtain the next course of action
 setting cannot be met, accomplish     paragraph (d)(1) of this AD.          from the FAA at the address
 the following:                        Reinspect within 25 hours TIS after   referenced in paragraph (f) of this
(i) Adjust the fuel servo. This        the fuel servo adjustment.            AD. We recommend you use an
 adjustment or any replacement must                                          electronic strobe to verify RPM
 be accomplished by an appropriately-                                        settings when making any
 rated repair station; and                                                   adjustment.
(ii) Repeat the inspection specified
 in paragraph (d)(1) of this AD.
(3) Add the following information to  Within the next 10 hours TIS after    The owner/operator holding at least
 the end of page 3-20, Section 3       April 20, 2001 (the effective date    a private pilot certificate as
 Emergency Procedures of the Cessna    of this AD), unless already           authorized by section 43.7 of the
 172R or 172S Pilot's Operating        accomplished.                         Federal Aviation Regulations (14
 Handbook (POH) and FAA-approved                                             CFR 43.7) may insert the
 Airplane Flight Manual (AFM):                                               information into the POH as
``IDLE POWER ENGINE ROUGHNESS                                                specified in paragraph (d)(3) of
An excessively rich idle fuel flow                                           this AD. You may insert a copy of
 may cause low speed engine                                                  this AD into the appropriate
 roughness during flight. During                                             sections of the POH to comply with
 most in-flight low engine speeds                                            this action. Make an entry into the
 (power off stalls, approach to                                              aircraft records showing compliance
 landing, etc.), the mixture control                                         with portion of the AD in
 is normally in the full-rich                                                accordance with section 43.9 of the
 position. However, to improve                                               Federal Aviation Regulations (14
 engine roughness (caused by an                                              CFR 43.9).
 improperly adjusted fuel servo)
 during low engine speeds while in
 flight, you should rotate the
 vernier mixture control (leaning of
 fuel mixture). You may also have to
 lean the fuel mixture if this low
 engine speed results in power loss
 and you need to restart the engine
 during flight. In all cases, you
 should land the airplane at the
 nearest airport for repairs if low
 speed engine roughness requires you
 to adjust the fuel mixture control
 to improve engine operation''
(4) Insert the following information  Within the next 10 hours TIS after    The owner/operator holding at least
 into the applicable Cessna Pilot's    April 20, 2001 (the effective date    a private pilot certificate as
 Operating Handbook (POH) and FAA-     of this AD), unless already           authorized by section 43.7 of the
 Operating Handbook (POH) and FAA-     accomplished.                         Federal Aviation Regulations (14
 approved Airplane Flight Manual                                             CFR 43.7) may insert the
 (AFM):                                                                      information into the POH as
``NORMAL PROCEDURES (Before Takeoff)                                         specified in paragraph (d)(4) of
 item 13. Throttle: 1. Vertify                                               this AD. You may insert a copy of
 smooth engine operation at idle                                             this AD into the appropriate
 speed of 575 to 625 RPM. 2. 1000                                            sections of the POH to comply with
 RPM or LESS''                                                               this action. Make an entry into the
                                                                             aircraft records showing compliance
                                                                             with portion of the AD in
                                                                             accordance with section 43.9 of the
                                                                             Federal Aviation Regulations (14
                                                                             CFR 43.9).
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[[Page 17348]]

    (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. Submit 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 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 (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 Mr. Paul Pendleton, 
Aerospace Engineer, Wichita Aircraft Certification Office, FAA, 1801 
Airport Road, Mid-Continent Airport, Wichita, Kansas 67209; 
telephone: (316) 946-4143; 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 
sections 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 accomplish the requirements of this AD.
    (h) When does this amendment become effective? This amendment 
becomes effective on April 20, 2001.

    Issued in Kansas City, Missouri, on March 23, 2001.
David R. Showers,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 01-7831 Filed 3-29-01; 8:45 am]
BILLING CODE 4910-13-P